RU2847370C1 - Testing device for quality control of rod-shaped products (variations) and method for testing the quality of rod-shaped products (variations) - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: inventions relate to variants of a method for quality control of rod-shaped products and devices for implementing them for quality control of rod-shaped products, wherein the device comprises: a drum (4) defining an outer surface (13, 40) and containing a plurality of sockets (41), each socket (41) of said plurality being designed to receive a rod-shaped product; an inductive sensor (5) located at a socket (41) of said plurality, said inductive sensor (5) containing a coil (51) defining an internal volume (50) large enough to accommodate the end of a rod-shaped product therein, wherein the inductive sensor (5) is designed to register the characteristics of the current collector (12) in the rod-shaped product; wherein the coil (51) comprises a first half-coil and a second half-coil, wherein the first half-coil and/or the second half-coil are designed to be movable from a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a coil (51) in which current can flow, to a second working position in which the first coil and the second coil are separated from each other and current cannot flow, and vice versa; wherein the first half-coil is located below the outer surface (13, 40) of the drum (4), and the second half-coil is located above the outer surface (13, 40) of the drum (4); and an actuator (6) designed to move the first half-coil and the second half-coil from the first working position to the second working position and vice versa.

EFFECT: the ability to quickly detect defects associated with incorrect positioning or orientation of current collectors.

15 cl, 14 dwg

Description

The present invention relates to a testing device for quality control of rod-shaped articles, in particular aerosol-generating articles, in which a conductive strip that can be inductively heated, such as a susceptor of a tobacco part, is inserted into the aerosol-generating material.

Aerosol-generating devices are known that contain an aerosol-forming substrate and an induction heating device. The induction heating device contains an induction source that creates an alternating electromagnetic field, which induces heat-generating eddy currents and hysteresis losses in a current collector. The current collector is located in thermal proximity to the aerosol-forming substrate, such as tobacco. The heated current collector, in turn, heats the aerosol-forming substrate, which contains a material capable of releasing volatile compounds that can form an aerosol.

In some components, the current collector is located inside the aerosol generating component of the product.

Due to manufacturing tolerances, the current collector in a component may not be positioned correctly or oriented correctly. If the current collector remains in the incorrect position or orientation, this can lead to product defects in aerosol delivery when the component is used in an aerosol-generating device.

It is therefore desirable to detect such defects as early as possible to ensure that only compliant products are produced and to avoid unnecessary costs and waste.

Furthermore, components, including those containing current collectors, are processed at high speeds, typically 5,000 components per minute. Therefore, the time window during which such components can be inspected to determine their compliance with production requirements is comparatively short. For example, when components are positioned in the drum of a combining device, their rotational speed is high, and the time window for the sensor to capture the data necessary to assess the shape, position, or presence or absence of a current collector is approximately 200 milliseconds.

Russian Patent 2226968 C1, A24C 5/34, April 20, 2004, describes a cigarette inspection device containing four sensors: two for monitoring the ends and one for monitoring the middle section of a cigarette. The device detects a loose tobacco end, the presence of a filter at the other end, and the presence of a foil ring in the middle section. The fourth sensor provides the device with information to synchronize the operation of the device's units to detect the three inspection factors. The information, in binary form, is then fed to the input of a programmable logic controller (PLC) for data processing and rejection if any defects are detected. The programmable logic controller (PLC) scans the cigarette end multiple times to detect a loose tobacco end. The resulting data is sent to a shift register, which controls a rejection valve or similar device, which is activated to remove defective cigarettes from the production flow.

Accordingly, it is desirable to detect faults associated with current collectors at a relatively high speed.

According to a first aspect, the invention relates to an inspection device for quality control of rod-shaped articles, which comprises a drum defining an outer surface and containing a plurality of seats, wherein each seat of said plurality is configured to receive a rod-shaped article. The inspection device preferably comprises an inductive sensor located at a seat of said plurality, wherein the inductive sensor comprises a coil defining an internal volume large enough to accommodate the end of the rod-shaped article, wherein the inductive sensor is configured to record the characteristic of a current collector in the rod-shaped article. Preferably, the coil comprises a first half-coil and a second half-coil, wherein the first half-coil and the second half-coil are configured to move from a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a coil in which current can flow, to a second operating position, in which the first half-coil and the second half-coil are separated from each other, and vice versa.

According to another aspect of the present invention, a rod-shaped article is provided. The rod-shaped article may, for example, be a component of an aerosol-generating article. The component is preferably rod-shaped. Preferably, the rod-shaped article defines a longitudinal axis. Preferably, the rod-shaped article defines a first end and a second end.

Preferably, the cross-section of said rod-shaped article along a plane transverse to its longitudinal axis is circular or oval. However, the rod-shaped article may also have a rectangular or polygonal cross-section. The rod-shaped article comprises an outer surface, preferably substantially cylindrical, that extends along the longitudinal axis. In the case of substantially cylindrical rod-shaped articles, the longitudinal axis corresponds to the axis of the cylinder.

Preferably, the rod-shaped article comprises an aerosol-generating article, or a component of an aerosol-generating article, or more than one component of an aerosol-generating article. Said component of the aerosol-generating article may comprise an aerosol-forming substrate. The aerosol-forming substrate may comprise homogenized tobacco material.

The rod-shaped article further comprises a current collector. The current collector is preferably in thermal contact with the aerosol-forming substrate. Thermal contact is created to heat the aerosol-forming substrate. When heated, the aerosol-forming substrate releases the aerosol. Preferably, the current collector is surrounded by the aerosol-forming substrate. Preferably, the current collector is fully inserted into said component of said rod-shaped article, i.e., the current collector is not visible from the outside of said rod-shaped article. Preferably, the current collector is surrounded by the aerosol-forming substrate in all directions.

Preferably, the current collector defines a longitudinal axis. Preferably, the current collector is located closer to the first end of said rod-shaped article than to the second end of said rod-shaped article. If a plane perpendicular to the longitudinal axis is taken and the rod-shaped article is divided into a first half containing the first end and a second half containing the second end, the current collector is preferably located predominantly in the first half. Preferably, the current collector is located at the first end of the rod-shaped article or near it. Preferably, the current collector is completely inserted into a component of said rod-shaped article. Preferably, the current collector extends from the first end to the second end of said component of said rod-shaped article. Preferably, the current collector defines a longitudinal axis. Preferably, the current collector is inserted into the rod-shaped article in such a way that its longitudinal axis is parallel to the longitudinal axis of said rod-shaped article. Preferably, the longitudinal axis of the current collector is parallel to the longitudinal axis of the rod-shaped article or forms an angle with it of less than 20 degrees. More preferably, the longitudinal axis of the current collector and the longitudinal axis of the rod-shaped article are congruent.

The longitudinal axis of the current collector can be the axis of symmetry of the current collector.

The current collector is made of a conductive material. Preferably, the current collector is made of metal. Preferably, the current collector is made of a ferromagnetic material. Although the current collector is made of a conductive material, it can be coated with other materials, either solid, such as a layer of another material, or liquid, such as a gel.

Preferably, the current collector is in the form of a strip. Its thickness preferably ranges from 30 micrometers to 60 micrometers. Its length preferably ranges from 5 millimeters to 20 millimeters.

Preferably, the rod-shaped product is wrapped in a sheet of wrapping paper.

The present invention also includes a drum. The drum defines an axis of rotation around which the drum is configured to rotate. The drum can be driven mechanically, for example, by a drum drive device comprising a gear mechanism or a toothed belt. The drum can be driven by an electrical drum drive device. The drum is preferably cylindrical in shape and comprises an outer surface. The outer surface is, for example, a substantially cylindrical surface having the drum's axis of rotation as its geometric center.

The drum is configured to transport and rotate a rod-shaped article. Preferably, the drum is configured to transport and rotate a plurality of rod-shaped articles. Preferably, the drum is configured to transport and rotate N rod-shaped articles, where 5<N<100, more preferably 20<N<50. In some embodiments, the drum comprises 40 cavities.

The drum comprises at least a socket. Preferably, the sockets are formed on the outer surface of the drum. The drum is preferably configured to hold a rod-shaped article in the socket during transportation. For example, the drum is configured to hold the rod-shaped article in the socket during rotation of the drum about its axis of rotation. The socket preferably extends longitudinally along the axis of the socket. The socket is configured to receive said rod-shaped article during rotation of the drum. Preferably, the rod-shaped article enters the socket such that its longitudinal axis is parallel to the axis of the socket. Preferably, each socket is configured such that the rod-shaped article can be placed therein when the axis of the socket and the longitudinal axis of said rod-shaped article are parallel. More preferably, the axis of the socket and the longitudinal axis of the rod-shaped article are congruent. The socket is preferably configured to accommodate a single rod-shaped article.

Preferably, the socket axis is parallel to the drum's axis of rotation. Thus, when a rod-shaped article is positioned in the socket, the longitudinal axis of said rod-shaped article is preferably parallel to the drum's axis of rotation. Preferably, all sockets are formed on the drum's peripheral surface. More preferably, the sockets are spaced equally apart along the drum's outer surface.

Preferably, all the pockets in the drum have the same geometric shape. For example, each pocket comprises a receiving surface adapted to contact the outer surface of the rod-shaped article. The receiving surface preferably comprises a portion of a recessed surface, such as a cylindrical surface. The receiving surface is part of the outer surface of the drum. The receiving surface may be a portion of a cylindrical surface having a diameter equal to or slightly larger than the diameter of the rod-shaped article being transported by the drum. The axis of the receiving surface defines the axis of the pocket.

Preferably, the axis of the nest is parallel to the axis of rotation of the drum, accordingly, when the rod-shaped products are positioned in the nests of the drum, their longitudinal axes are parallel to the axis of rotation of the drum.

Preferably, the drum also comprises a first side surface and a second side surface located on two opposite sides of the outer surface. Preferably, the receptacles extend from the first side surface to the opposite second side surface. The receptacle may extend to the first side surface, the second side surface, or both, such that the receptacle is "open" at both ends. Alternatively, the ends of the receptacle do not extend to the first side surface or the second side surface, in which case the receptacle is a "closed" receptacle.

Each nest preferably contains an evacuation port connected to a evacuation or pneumatic system designed to retain the rod-shaped article in the nest by evacuation during drum rotation. More than one port may be present, depending, for example, on the size and weight of the rod-shaped article.

At least one of the drum cavities is connected to an inductive sensor. More preferably, a plurality of drum cavities, and even more preferably, all drum cavities, are connected to an inductive sensor. In the art, "inductive sensor" and "inductive sensor" are synonymous. Inductive sensors use currents induced by magnetic fields to detect nearby conductive objects, such as metal objects. The inductive sensor comprises an inductor, which creates a magnetic field, such as a high-frequency magnetic field. When a conductive object, such as a susceptor located in a rod-shaped article, is located near an alternating magnetic field, a current will flow through the conductive object. The resulting current in the conductive object generates a new magnetic field, which is directed opposite to the original magnetic field created by the current flowing in the coil. The end result is a change in impedance, such as the resistance, of the coil-and-sensor system in an inductive sensor. By measuring impedance or a parametric function of impedance, the sensor can determine when a conductive material is brought close to the inductive sensor. The change in impedance depends on the type of conductive material the object is made of, the distance between the object and the sensor, and the size and shape of the object.

An inductive sensor can be, for example, an LCD 1101 integrated circuit from Texas Instruments. Preferably, the inductive sensor measures the equivalent resistance of the current collector. The inductive sensor can measure the impedance and resonant frequency of the equivalent "coil and current collector" system by adjusting the closed-loop oscillation amplitude at a constant level while monitoring the energy dissipated by the resonator. By measuring the power supplied to the resonator, the inductive sensor can determine the equivalent parallel resistance of the resonator, which it then provides as a digital value.

Thus, an inductive sensor is connected to a drum socket, preferably a plurality of inductive sensors are connected to a plurality of drum sockets, one sensor per drum, for recording a characteristic of a current collector contained in a rod-shaped article.

A current collector characteristic may be the presence or absence of a current collector. A current collector characteristic may be the length of the current collector. A current collector characteristic may indicate the nature and conformity of the current collector's shape or composition. An inductive sensor can record more than one current collector characteristic. These characteristics may also include the current collector's size and the mass of the material from which the current collector is formed.

The characteristic of the current collector to be measured is preferably measured by measuring the parametric function of the impedance of the coil or the coil and current collector system.

The parametric impedance function is preferably the coil impedance Z itself, or the equivalent resistance of the coil, or the inductance of the coil.

An inductive sensor comprises a coil that defines an internal volume. The internal volume is defined by the turns of the coil. For example, an inductive sensor comprises a cylindrical coil containing multiple turns of wire. Preferably, the coil is coreless, meaning the internal volume is filled with air. Preferably, the internal volume of the coil is large enough to allow a rod-shaped object to be inserted, at least partially, into the coil. The total length of the coil preferably exceeds the length of the current collector. The length of the current collector, if measuring the length of the current collector is desired, refers to the nominal length of the current collector. To ensure proper insertion, the internal diameter of the coil preferably exceeds the diameter of the rod-shaped object. Preferably, the coil defines a longitudinal axis, hereinafter referred to as the coil axis.

Preferably, the rod-shaped object is inserted into the coil of the inductive sensor. The insertion can be complete, meaning the rod-shaped object is entirely contained within the coil, or partial, meaning only a portion of the rod-shaped object is contained within the coil. However, it is preferable to insert the rod-shaped object into the coil such that the current collector is located entirely within the coil's internal volume at the end of the insertion.

Preferably, the inductive sensor coil is mounted on the drum receptacle such that the coil axis and the receptacle axis are parallel to each other. This, in turn, means that the coil axis and the longitudinal axis of the rod-shaped article, when present in the receptacle, are also preferably parallel.

An inductive sensor is used to measure the current collector inside a rod-shaped workpiece. For this reason, the testing device preferably includes a control unit. The control unit is preferably electrically connected to the inductive sensor. The control unit processes signals from the inductive sensor to evaluate the current collector's characteristics. The control unit can be part of the inductive sensor.

In order to insert a rod-shaped product into the said inductive sensor, a relative movement is carried out between the rod-shaped product and the inductive sensor.

Preferably, the rod-shaped object is inserted into the coil from the first end. The current collector is preferably located closer to the first end than to the second end. Therefore, when inserting from the first end, a shorter coil is required to fully insert the current collector into the coil's interior than when inserting from the second end. Therefore, only a limited portion of the rod-shaped object needs to enter the coil to test the current collector's characteristics.

The coil comprises a first half-coil and a second half-coil. The first half-coil and the second half-coil are two parts of a coil cut along a plane parallel to the longitudinal axis of the coil. Accordingly, the first half-coil and the second half-coil may have different dimensions. More preferably, each of the first half-coil and the second half-coil is half of a coil cut along a plane containing the longitudinal axis of the coil. Each half-coil comprises a plurality of half-turns. Each half-turn is, for example, an arc of a circle, more preferably a semicircle. The arc of a circle of the first half-coil and the corresponding arc of a circle of the second half-coil form a turn of the coil. The first half-coil and the second half-coil are movable relative to each other. The movement performed by the first half-coil, the second half-coil, or both of them is preferably a displacement, i.e., a linear movement. The first half-coil and the second half-coil may be in a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a complete coil, and electric current can flow in the turns of the coil. In this first operating position, each half-turn of the first half-coil corresponds to a half-turn of the second coil. Further, each half-turn of the second half-coil corresponds to a half-turn of the first half-coil. In the first operating position, the contact between said first half-coil and said second half-coil is such that current can flow in the coil formed by said two half-coils. Accordingly, the inductive sensor can determine the characteristic of the current collector. Conductive strips can be formed, for example, on the outer surface of the drum where the second half-coil or the first half-coil slides.

The first half-coil and the second half-coil may be in a second operating position, in which the first half-coil and the second half-coil are located at a certain distance from each other. In this second operating position, not all turns are full, or none of the turns are full. There is a "gap" between the first half-coil and the second half-coil. The presence of a gap between the first half-coil and the second half-coil means that at least a half-turn of the first half-coil does not correspond to a half-turn of the second half-coil. Preferably, in the second operating position, the two half-coils are arranged one after the other along the longitudinal axis of the coil with a gap between them. If, in the second operating position, some of the half-turns of the first half-coil are in contact with some of the half-turns of the second half-coil, current may flow in said number of formed full turns, but in this configuration, no measurement is performed. In an alternative embodiment, in the second operating position, no current may flow in the coil. The current flow depends on the type of electrical contact between the first half-coil and the second half-coil.

The first half-coil and the second half-coil are configured to move from the first working position to the second working position and vice versa.

When it is said that "the first half-coil and the second half-coil are movable from the first operating position to the second operating position," this means that only the first half-coil can move, only the second half-coil can move, or both the first half-coil and the second half-coil can move.

The first half-reel and the second half-reel may be moved in the following manner. The first half-reel may move linearly relative to the second half-reel. The second half-reel is integral with the outer surface of the drum, meaning that the second half-reel rotates with the outer surface but does not move relative to the outer surface (i.e., the second half-reel is stationary relative to the outer surface). In an alternative embodiment, the second half-reel may move linearly relative to the first half-reel. The first half-reel is stationary relative to the outer surface of the drum, meaning that the first half-reel rotates with the outer surface but does not move relative to the outer surface. In an alternative embodiment, both the first half-reel and the second half-reel move relative to each other. Each of the first half-reel and the second half-reel may reciprocate toward and away from the other of the first half-reel and the second half-reel.

The first half-coil is positioned beneath the outer surface of the drum. The term "below" the surface indicates that the first half-coil extends radially inward within the drum. To establish an electrical connection with the second half-coil, the contact ends of the half-turns of the first half-coil protrude from the outer surface of the drum in such a way that an electrical connection can be established with the half-turns of the second half-coil. These ends of the half-turns of the first half-coil are preferably located substantially flush with the outer surface of the drum.

The second half-spool preferably extends above the outer surface of the drum. The drum may, for example, contain guides, such as a pair of guides for each slot, along which the second half-spool can move toward and away from the first half-spool.

The outer surface of the drum may also contain conductive strips, which allows the second half-coil to be moved toward and away from the first half-coil, while at the same time providing an electrical connection between the two half-coils.

The outer surface may contain electrical tracks along which the first half-coil moves, such that when the relative position of the first half-coil and the second half-coil is such that a full coil is formed (the first half-coil and the second half-coil are in the first working position), the ends of the half-turns of the first half-coil correspond to the ends of the half-turns of the second half-coil, current can flow in the turns formed in this way due to the fact that a conductive track is present between them.

The movement of the first half-coil, the second half-coil, or both is accomplished by an actuator. The actuator may be a linear actuator. Preferably, the movement is linear in a direction parallel to the axis of the coil. Preferably, the movement is linear parallel to the axis of the socket. The actuator may, for example, include a pneumatic actuator containing a pusher. The pusher is attached to the second half-coil and thereby moves toward and away from the first half-coil in the same manner. The actuator may comprise a rack and pinion mechanism.

During operation, the rod-shaped article is positioned in the reel's cavity, where the current collector's characteristic is recorded by an inductive sensor. The inductive sensor can measure the parametric function of the coil's impedance. Preferably, the inductive sensor measurement is repeated, i.e., multiple measurements of the current collector's characteristic are taken during the insertion of the rod-shaped article into the reel. Preferably, multiple measurements are also taken during the removal of the rod-shaped article from the reel. Positioning of the said rod-shaped article in the cavity can be accomplished, for example, by transferring it from another reel or from a conveyor. Preferably, when the rod-shaped article is transferred into the cavity, the first half-reel and the second half-reel are in the second working position, which allows positioning of the rod-shaped article in the cavity. For example, the positioning is such that the rod-shaped article is positioned at least partially above the first half-reel.

When the rod-shaped workpiece is positioned in the nest, the first and second half-coils are moved by the actuator to the first operating position, forming a coil. As the first and second half-coils move to the first operating position, the second half-coil shifts over the rod-shaped workpiece, enclosing a portion of the rod-shaped workpiece.

The coil ensures current flow along its entire length, allowing the current to be recorded. The recording performed by the inductive sensor can be related to the presence or absence of the current collector. If the current collector is absent, no eddy currents are generated, and there is no change in the magnetic field generated by the coil. Furthermore, the measurements performed by the inductive sensor can be related to the current collector's size. The output signal of an inductive sensor depends on the material, size, shape, and distance of the current collector. If the material is known and the distance is measurable, the size or shape of the current collector can be measured. Knowing the size, for example, knowing the mass, can provide current collector measurements, for example, based on the minimum or maximum signal relative to the impedance of the "coil and current collector" system, measured by the inductive sensor. Indeed, the impedance of the "coil and current collector" also depends on the current collector's characteristics.

Accordingly, to obtain a current collector characteristic, no movement of the rod-shaped object is required after it has been positioned in the drum cavity. Measurements can be performed very quickly due to the rapid measurement capabilities of the inductive sensor. Moving the rod-shaped object does not require complex mechanical components. In the drum, the rod-shaped object is not subject to deformation due to improper handling.

The testing device preferably comprises a control unit. The control unit is preferably connected to an inductive sensor for data exchange. The inductive sensor is preferably configured to generate one or more signals regarding the characteristics of the current collector, which are sent to the control unit.

The testing device comprises a control unit configured to command the actuator to move the first half-coil, the second half-coil, or both of them, from the second operating position to the first operating position when the rod-shaped article is located in the receptacle. To accommodate the rod-shaped article in the receptacle of the drum, the receptacle is preferably "free," meaning that no other objects should be positioned above the receptacle that would impede the positioning of the rod-shaped article. The rod-shaped article can be transferred to the receptacle of the drum, for example, from another drum or from a conveyor. Therefore, it is preferable that when the rod-shaped article is positioned in the receptacle, the first half-coil and the second half-coil are in the second operating position, separated from one another, such that the volume above the receptacle is "free," and the rod-shaped article can be positioned in the receptacle without hindrance. When the rod-shaped article is in the socket, the first half-coil and the second half-coil move to the first operating position, and the current collector's characteristics can be determined. The actuator moves the first half-coil or the second half-coil until the half-turns of the first half-coil coincide with the complementary half-turns of the second half-coil. The control unit commands the actuator to move the second half-coil until the first operating position is reached. The control unit's command can be initiated by an additional sensor that responds to the presence or absence of the rod-shaped article in the socket. Thus, when the sensor detects the presence of the rod-shaped article, it sends a signal to the control unit, which, in turn, sends a signal to the actuator to move the first half-coil and the second half-coil to the first operating position, and determination can be performed using the inductive sensor. In an alternative embodiment, the command from the control unit to the actuator is synchronized with the rotation of the drum. The control unit is configured to receive or determine the drum's angular velocity and the insertion point of the rod-shaped product during drum rotation. Using this information, the control unit can calculate the angular position of each rod-shaped product within the drum. The control unit can then issue commands to the actuators in the receptacles containing the inductive sensor, causing the first and second semi-coils to move from the second operating position to the first operating position at a predetermined frequency.

The nest preferably comprises a receiving surface, a portion of the outer surface of the drum, and a first half-spool located beneath the receiving surface of the nest. Preferably, the first half-spool is located beneath the receiving surface of the nest, where the rod-shaped article is positioned. The second half-spool is preferably movable from a first operating position, in which it is located above the nest, to a second operating position, in which it is not located above the nest. In the second operating position, the second half-spool is shifted toward the end of the nest. For example, the second half-spool is shifted toward the side surface of the drum. Preferably, the second half-spool is moved along a direction parallel to the axis of the nest.

According to another aspect, the invention relates to an inspection device for quality control of rod-shaped articles, wherein the device comprises: a drum containing a plurality of seats, wherein each seat of said plurality is configured to receive a rod-shaped article. The inspection device may comprise an inductive sensor located at a seat of said plurality, wherein the inductive sensor comprises a coil defining an internal volume large enough to accommodate the end of the rod-shaped article, wherein the inductive sensor is configured to record a characteristic of a current collector in the rod-shaped article. The inspection device may comprise a compressed air system aligned with said seat of said plurality. The inspection device may comprise an actuator configured to activate the compressed air system so that it blows air when the rod-shaped article is located in the seat, to push the rod-shaped article into the coil.

For example, the compressed air system may include a nozzle configured to discharge a stream of compressed air. The primary direction of said compressed air stream is preferably parallel to the longitudinal axis of the socket. Accordingly, the compressed air stream preferably impinges on one end of said rod-shaped article and pushes it toward the spool. Preferably, the spool is aligned with the socket, i.e., the longitudinal axis of the spool is parallel to or coincides with the longitudinal axis of the rod-shaped article. Preferably, the longitudinal axis of the spool is parallel to the mid-axis of the compressed air stream.

Preferably, the compressed air system comprises a second nozzle for ejecting a stream of compressed air opposite to the first stream of compressed air to push the rod-shaped article beyond the coil. Preferably, the second nozzle faces the first nozzle at a predetermined distance. Preferably, said predetermined distance exceeds the length of the rod-shaped article. Preferably, the first nozzle and the second nozzle are located on opposite sides of the coil.

The size of the internal volume of the coil is such that the rod-shaped article can be inserted into the coil from one of its ends, at least partially.

In this aspect, the drum and rod-shaped article are the same as in the previous aspect, and their characteristics are not repeated here. Furthermore, the characteristics measured by the pantograph are the same as those described in the previous aspect.

In this aspect, the relative movement between the rod-shaped article and the inductive sensor includes at least movement of the rod-shaped article toward the inductive sensor coil. Preferably, the relative movement only includes movement of the rod-shaped article toward the inductive sensor coil. The inductive sensor coil is preferably fixed and moves along the outer surface of the drum, i.e., the coil is stationary relative to the outer surface of the drum. Thus, the coil rotates along with the outer surface of the drum. Preferably, the rod-shaped article is positioned in a receptacle. Once positioned in the receptacle, the rod-shaped article is inserted into the inductive sensor coil using a stream of compressed air.

The insertion of the rod-shaped product by means of the discharge of a stream of compressed air is carried out when the rod-shaped product is positioned in the drum socket.

The testing device comprises a control unit. Preferably, the control unit is coupled to an inductive sensor for data exchange. Preferably, the inductive sensor is configured to generate one or more signals related to the characteristics of the current collector. These characteristics may include: the presence or absence of the current collector, the measurement of the current collector, and the mass of the material from which the current collector is formed. Preferably, the control unit is coupled to the inductive sensor for data exchange.

Preferably, the inductive sensor is configured to output a signal representing a parametric function of the coil impedance.

Preferably, the testing device comprises a control unit configured to command the compressed air system to emit a stream of compressed air when the rod-shaped article is located in the cavity. The cavity may be empty when no rod-shaped article is positioned in the cavity. Alternatively, the cavity may contain a rod-shaped article positioned therein. The compressed air system is preferably activated, i.e., the compressed air stream is preferably emitted, when the rod-shaped article is positioned in the cavity. In this case, the compressed air can push the rod-shaped article into the coil of the inductive sensor. The rod-shaped article can be transferred to the cavity of the drum, for example, from another drum or from a conveyor. When the rod-shaped article is in the cavity, the control unit preferably commands the compressed air system to emit a stream of air. The control unit command can be initiated by an additional sensor that responds to the presence or absence of the rod-shaped article in the cavity. Accordingly, when the sensor detects the presence of a rod-shaped object, it sends a signal to the control unit, which in turn signals the compressed air system to emit a stream of air to push the rod-shaped object into the reel. The control unit is configured to receive or determine the drum's angular velocity and the insertion point of the rod-shaped object into the drum during drum rotation. Using this information, the control unit can calculate the angular position of each rod-shaped object in the drum. The control unit can command the compressed air system at a predetermined frequency so that it emits a stream of air into the receptacle only when the receptacle is occupied by a rod-shaped object.

A single compressed air system may be provided for all nests in the plurality. The compressed air system may be located on the outer surface of the drum. The compressed air system preferably faces the first side surface or the second side surface of the drum. The compressed air system may be stationary, meaning it does not rotate with the drum. The compressed air system may discharge a stream of compressed air into one nest at a time. However, the compressed air system may discharge a stream of compressed air into multiple nests of the plurality as they pass in front of the nozzle of the compressed air system. The nozzle is stationary, and the nests move in front of the nozzle due to the rotation of the drum. Preferably, a new stream of air is discharged each time a new nest passes in front of the nozzle.

Preferably, in any aspect, the drum has an axis of rotation, and each of the plurality of pockets defines a pocket axis, wherein the axis of rotation and the pocket axis are parallel to each other. Preferably, the axes of all pockets are parallel to the axis of rotation of the drum. Preferably, the axes of all pockets are parallel to each other. This, in turn, means that when rod-shaped articles are positioned in the pockets, the longitudinal axes of said rod-shaped articles are parallel to the axis of rotation. To determine the characteristics of the current collector, relative movement between the rod-shaped article and the coil is necessary (e.g., either the semi-coil moves, or the rod-shaped article moves, or both). A configuration in which the rod-shaped articles are parallel to the axis of rotation of the drum maximizes the number of rod-shaped articles that can be simultaneously placed in the drum.

In a preferred embodiment of the present invention, the coil length ranges from 20 millimeters to 40 millimeters. Preferably, the coil length exceeds the length of the current collector, such that the current collector can be fully inserted into the coil. The coil length is measured along the coil axis.

Preferably, the testing device comprises a control unit electrically connected to the inductive sensor. Preferably, the control unit is configured to receive a signal from the inductive sensor and compare the signal with a threshold. The inductive sensor preferably measures the parametric impedance function of the system formed by the coil and the current collector, or the coil. Eddy currents are generated in the current collector, which in turn generate a magnetic field. The parametric impedance function measured by the inductive sensor depends on the characteristics of the current collector. In some embodiments of the inductive sensor, the inductive sensor measures resistance. In particular, the inductive sensor is configured to measure the series resistance equivalent to the current collector. Preferably, the current collector is considered acceptable if its resistance, measured by the inductive sensor, lies in the range from 200 milliohms to 500 milliohms. Due to the fact that the composition of the current collector is known, comparison with the threshold allows determining the characteristics of the current collector.

The absence of changes in the coil impedance occurs if the rod-shaped product does not contain a current collector, taking into account that usually the rod-shaped product does not contain other conductive objects besides the current collector.

More preferably, the control unit is configured to calculate the length of a current collector located in a rod-shaped object. The current collector length can be calculated by monitoring the change in the inductive sensor's output signal in accordance with the position of the rod-shaped object within the coil. The inductive sensor's output signal depends on the impedance of the coil and current collector system. The impedance reaches its maximum (or minimum) level when the current collector is fully inserted into the coil and begins to decrease (or increase) as soon as the end of the current collector exits the coil. By comparing the signal with the position of the rod-shaped object within the coil, the exact current collector length can be determined.

Preferably, a rejection device is provided that is capable of rejecting rod-shaped articles based on a signal emitted by an inductive sensor. If the inductive sensor detects that one of the characteristics of the current collector within the rod-shaped article deviates from specifications, for example, the current collector is missing or its length is too short or too long, then the rod-shaped article is preferably not subjected to further processing. For example, a rod-shaped article containing a "defective" current collector is transferred to a rejection drum that is different from the drum where rod-shaped articles containing a compliant current collector are transferred. Preferably, the control unit controls the pumping system that holds the rod-shaped article in the socket such that rod-shaped articles with a defective current collector are released from the socket differently than rod-shaped articles containing a compliant current collector. Differentiation between a compliant pantograph and a defective one is preferably performed by the control unit. Preferably, differentiation is based on the pantograph's characteristic, determined by an inductive sensor.

Preferably, the drum contains multiple inductive sensors, one for each cavity in said plurality of cavities. This allows for the rapid inspection of multiple rod-shaped products.

Preferably, the coil has a diameter in the range of 10 millimeters to 20 millimeters. For the purposes of this document, coil diameter refers to the coil's internal diameter, i.e., the diameter accessible for insertion of the said rod-shaped article. The coil's size is such as to allow insertion of the rod-shaped article.

Preferably, said socket defines the socket axis, and said coil defines the coil axis, wherein the coil axis and the socket axis are preferably parallel to each other. To measure the current collector's characteristic, a rod-shaped object is inserted into the coil. If the axes of the coil and the rod-shaped object are parallel, the relative movement required between the coil and the rod-shaped object is a simple linear motion. Accordingly, the mechanical design is relatively simple.

According to another aspect, the present invention relates to an inspection device comprising: a first drum comprising a first plurality of seats, wherein each seat of the first plurality of seats is configured to receive a rod-shaped article, wherein the first drum defines a first outer surface. The inspection device may also comprise a first inductive sensor positioned at a seat of said first plurality, wherein the first inductive sensor comprises a first coil defining an internal volume large enough to accommodate a first end of the rod-shaped article, wherein the first inductive sensor is configured to record a characteristic of a first current collector in the rod-shaped article. Preferably, the first coil comprises a first half-coil and a second half-coil, wherein the first half-coil and the second half-coil are configured to move from a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a first coil in which current can flow, to a second operating position, in which the first half-coil and the second half-coil are separated from each other, and vice versa. Preferably, the first half-coil is located under the first outer surface of the first drum, and the second half-coil is located above the first outer surface of the first drum. The testing device may also comprise a first actuator configured to move the first half-coil and the second half-coil of the first coil from the first operating position to the second operating position and vice versa in the first drum. The testing device may also comprise a second drum containing a second plurality of seats, wherein each seat from the second plurality is configured to receive a rod-shaped article, wherein the second drum defines a second outer surface. The testing device may also comprise a second inductive sensor located at a seat from said second plurality, wherein the second inductive sensor comprises a second coil defining an internal volume large enough to accommodate the second end of the rod-shaped article, wherein the second inductive sensor is configured to record a characteristic of the second current collector in the rod-shaped article. Preferably, the second coil comprises a first half-coil and a second half-coil, wherein the first half-coil and the second half-coil are movable from a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a second coil in which a current can flow, to a second operating position, in which the first half-coil and the second half-coil are separated from each other, and vice versa. Preferably, the first half-coil of the second coil is located under the second outer surface, and the second half-coil of the second coil is located above the second outer surface. The testing device may also comprise a second actuator configured to move the first half-coil and the second half-coil of the second coil from the first operating position to the second operating position and vice versa in the second drum. Preferably, the first drum and the second drum extend substantially tangentially to each other to ensure the possibility of transferring a rod-shaped article from the first drum to the second drum.

The testing device essentially comprises two drums, a first drum and a second drum, wherein each of the first drum and the second drum is implemented in accordance with the first aspect of the present invention described above. Two drums are preferably used when the rod-shaped article includes a first current collector and a second current collector. Preferably, the first current collector and the second current collector are located at two opposite distal ends of said rod-shaped article. Accordingly, the first drum with the first inductive sensor is used to test the first end of the rod-shaped article, in which the first current collector is present. The second drum with the second inductive sensor is used to test the second end of the rod-shaped article, in which the second current collector is present. In the first drum, the relative movement between the rod-shaped article and the coil is carried out along the first axis, and the relative movement between the rod-shaped article and the coil in the second drum is carried out along an axis parallel to the first axis, but in the opposite direction. Preferably, after inspection in the first drum, where the pantograph is tested, the rod-shaped product is transferred to the second drum. The transfer is preferably performed only if the first pantograph is not defective. The transfer is performed according to the standard method in the industry. This allows for a rapid, complete inspection of both the first and second pantographs.

According to another aspect, the present invention relates to an inspection device comprising: a first drum comprising a first plurality of seats, wherein each seat of the first plurality of seats is configured to receive a rod-shaped article. The inspection device preferably comprises a first inductive sensor located at a seat of said first plurality, wherein the first inductive sensor comprises a first coil defining an internal volume large enough to accommodate a first end of the rod-shaped article, wherein the first inductive sensor is configured to record a characteristic of a first current collector in the rod-shaped article. The inspection device preferably comprises a first compressed air system aligned with said seat of the first plurality. The inspection device preferably comprises a first actuator configured to activate the first compressed air system so that it blows air when the rod-shaped article is located in a seat of the first plurality to push it inside the first coil of the first drum. The testing device preferably comprises a second drum comprising a second plurality of seats, wherein each seat from the second plurality is configured to receive a rod-shaped article. The testing device preferably comprises a second inductive sensor positioned at a seat from said second plurality, wherein the second inductive sensor comprises a second coil defining an internal volume large enough to accommodate the second end of the rod-shaped article therein, wherein the second inductive sensor is configured to record a characteristic of the first current collector in the rod-shaped article. The testing device preferably comprises a second compressed air system aligned with said seat from the second plurality. The testing device preferably comprises a second actuator configured to activate the second compressed air system so that it blows out air when the rod-shaped article is located in said seat from the second plurality for pushing it inside the second coil of the second drum. Preferably, the first drum and the second drum extend substantially tangentially to each other, ensuring the possibility of transferring the rod-shaped article from the first drum to the second drum.

The testing device essentially comprises two drums, a first drum and a second drum, wherein each of the first drum and the second drum is implemented in accordance with the second aspect of the present invention described above. Two drums are used when the rod-shaped article includes a first current collector and a second current collector. Preferably, the first current collector and the second current collector are located at two opposite distal ends of said rod-shaped article. Accordingly, the first drum with the first inductive sensor is used to test the first end of the rod-shaped article, in which the first current collector is present. The second drum with the second inductive sensor is used to test the second end of the rod-shaped article, in which the second current collector is present. Accordingly, in the first drum, the relative movement between the rod-shaped article and the coil is carried out along the first axis, and the relative movement between the rod-shaped article and the coil in the second drum is carried out along an axis parallel to the first axis, but in the opposite direction. Preferably, after testing in the first drum, the rod-shaped article is transferred to the second drum. Preferably, the transfer is performed only if the first current collector is not defective. The transfer is performed according to the standard method in the field. This allows for a rapid, complete inspection of both the first and second current collectors.

Impedance refers to a generalized resistance expressed as a complex number. Impedance Z is a complex number representing the ratio V (voltage) / I (current). For an ideal inductor L, such as a coil, impedance Z _L is expressed by the formula:

Z _L =j ωL

where j is the imaginary unit, ω is the angular frequency of the exciting electrical signal, and L is the inductance of the coil.

Accordingly, the equivalent resistance R of the coil, measured in ohms, is equal to ωL.

Further, the term "rod-shaped article" may refer to any element that can be included in an aerosol-generating article or to the entire aerosol-generating article. Such elements are known in the art and are not described in further detail below. For example, such a rod-shaped article may comprise a filter plug, a heat source, a tobacco rod, a carbon element, and so on. Preferably, the rod-shaped article is an article containing plant material, in particular an article containing tobacco. The tobacco article may comprise a filler of shredded tobacco or reconstituted tobacco that forms an aerosol. The article may comprise a tobacco rod that can be combusted or heated. The rod-shaped articles according to the present invention may be complete, assembled aerosol-generating articles, or elements of aerosol-generating articles that are combined with one or more other components to form an assembled aerosol-generating article for producing an aerosol, such as, for example, a consumable part of a heated smoking device.

Preferably, the aerosol-generating article elements comprise a tobacco-containing material containing volatile tobacco flavor compounds that are released from the aerosol-forming substrate upon heating.

Preferably, the rod-shaped article may comprise a heat source or a volatile aroma generating component, such as a menthol capsule, a carbon element, or a current collector.

Accordingly, the rod-shaped article may comprise a plurality of components of the aerosol-generating article combined with each other, or even more than the aerosol-generating article.

In this document, the term "susceptor" refers to a material capable of converting electromagnetic energy into heat. When a susceptor is placed in an alternating electromagnetic field, eddy currents are typically induced in it and hysteresis losses may occur, leading to heating of the susceptor. Because the susceptor is located in thermal contact with the aerosol-forming substrate or in close thermal proximity to it, the aerosol-forming substrate is heated by the susceptor, resulting in aerosol formation. Preferably, the susceptor is located in direct physical contact with the aerosol-forming substrate, such as within the aerosol-forming tobacco substrate.

The current collector may be made of any material that can be inductively heated to a temperature sufficient to generate an aerosol from an aerosol-forming substrate. A preferred current collector may comprise or consist of a ferromagnetic material, such as a ferromagnetic alloy, ferritic iron, or ferromagnetic steel, or stainless steel. A suitable current collector may be made of or comprise aluminum. Preferred current collectors may be heated to a temperature exceeding 250 degrees Celsius. Suitable current collectors may comprise a non-metallic core with a metallic layer disposed on the non-metallic core, such as with metallic tracks formed on the surface of a ceramic core. The current collector may have a protective outer layer, such as a protective ceramic layer or a protective glass layer, enclosing the current collector. The current collector may comprise a protective coating made of glass, ceramic, or inert metal formed over the core material of the current collector.

The current collector may be a current collector composed of several materials and may comprise a first current collector material and a second current collector material. The first current collector material is located in direct physical contact with the second current collector material. The second current collector material preferably has a Curie temperature of less than 500°C. The first current collector material is preferably used primarily to heat the current collector when the current collector is placed in an alternating electromagnetic field. Any suitable material may be used. For example, the first current collector material may be aluminum or may be a ferrous metal, such as stainless steel. The second current collector material is preferably used primarily to indicate that the current collector has reached a specific temperature, and this temperature represents the Curie temperature of the second current collector material. The Curie temperature of the second current collector material can be used to regulate the temperature of the entire current collector during operation. Thus, the Curie temperature of the second current collector material should be lower than the ignition temperature of the aerosol-forming substrate. Suitable materials for the second current collector material may include nickel and certain nickel alloys.

Preferably, the current collector has the form of a fiber, rod, sheet, or tape. If the profile of the current collector has a constant cross-section, for example a circular cross-section, its preferred width or diameter is from about 1 millimeter to about 5 millimeters. If the profile of the current collector has the form of a sheet or tape, the sheet or tape preferably has a rectangular shape with a width of preferably from about 2 millimeters to about 8 millimeters, more preferably from about 3 millimeters to about 5 millimeters, for example 4 millimeters, and a thickness of preferably from about 0.03 millimeters to about 0.15 millimeters, more preferably from about 0.05 millimeters to about 0.09 millimeters, for example about 0.07 millimeters.

Preferably, the rod-shaped article may have a length of from about 5 millimeters to about 20 millimeters, preferably from about 8 millimeters to about 16 millimeters, for example, about 12 millimeters in length. In some cases, the rod-shaped article may have a length of from about 40 millimeters to about 85 millimeters.

Hereinafter, the term “length”, unless otherwise stated, refers to the length of a rod-shaped product along its longitudinal axis.

In the following text, the term "rod-shaped" refers to a substantially cylindrical element with a substantially cylindrical, oval, or elliptical cross-section. However, other prismatic shapes with different cross-sections are also possible.

As used herein, an "aerosol-generating article" is any article that generates an inhalable aerosol by heating an aerosol-forming substrate. This term includes articles that contain an aerosol-forming substrate that is heated by an external heat source, such as an electric heating element. An aerosol-generating article may be a non-combustible aerosol-generating article, which is one that releases volatile compounds without combusting the aerosol-forming substrate. An aerosol-generating article may be a heated aerosol-generating article, i.e., an aerosol-generating article containing an aerosol-forming substrate that is heated, rather than combusted, to release volatile compounds capable of forming an aerosol. This term includes articles that contain an aerosol-forming substrate and an integral heat source, such as a combustible heat source.

An aerosol-generating device may include a mouthpiece. The mouthpiece may be located at the mouthpiece end or at a downstream end of the aerosol-generating device.

The aerosol generating article may comprise at least one filter element.

The filter segment may be a cellulose acetate filter plug made from cellulose acetate tow. The filter segment may have low particle filtration efficiency or very low particle filtration efficiency. The filter segment may be located longitudinally away from the aerosol-forming substrate. The filter segment may have a longitudinal length of approximately 5 millimeters to approximately 14 millimeters. The filter segment may have a length of approximately 7 millimeters.

The specified plurality of elements of the aerosol generating article may comprise at least one of a support element and an aerosol cooling element.

Preferably, the aerosol-generating article comprises a wrapper enclosing said plurality of rod-shaped aerosol-generating article elements. The wrapper may comprise at least one of paper and foil.

As used herein, the term "aerosol-forming substrate" refers to a substrate formed from or containing an aerosol-forming material that is capable of releasing volatile compounds upon heating to generate an aerosol. The aerosol-forming substrate may comprise tobacco material or may comprise non-tobacco material, or a combination of both tobacco material and non-tobacco material. The aerosol-forming substrate may be a cellulosic material impregnated with nicotine, preferably containing one or more flavoring agents. The aerosol-forming substrate comprises tobacco material, preferably homogenized tobacco material, advantageously containing one or more aerosol-forming agents. As used herein, the term "homogenized tobacco material" refers to a material formed by agglomerating particulate tobacco.

Preferably, the aerosol-forming substrate comprises volatile tobacco flavor compounds that are released from the aerosol-forming substrate upon heating. The aerosol-forming substrate may comprise or consist of a filler of cut blended tobacco, or may comprise a homogenized tobacco material. The homogenized tobacco material may be formed by agglomerating loose tobacco. The aerosol-forming substrate may further comprise a non-tobacco material, such as a homogenized plant-based material other than tobacco.

Preferably, the aerosol-forming substrate is a tobacco sheet, preferably corrugated, containing tobacco material, fibers, a binder, and an aerosol-forming agent. Preferably, the tobacco sheet is a molded sheet. The molded sheet is in the form of reconstituted tobacco, which is formed from a suspension containing tobacco particles, fiber particles, an aerosol-forming agent, a binder, and, for example, flavorings.

Tobacco particles may be in the form of tobacco dust, with particle sizes ranging from 30 micrometers to 250 micrometers, preferably ranging from 30 micrometers to 80 micrometers or from 100 micrometers to 250 micrometers, depending on the desired sheet thickness and the forming gap, with the forming gap generally determining the sheet thickness. The tobacco particle size refers to its Dv95 size in the volume distribution.

Fiber particles may also be included, including tobacco stem, petiole, or other tobacco plant material, and other cellulose-based fibers, such as wood fibers, having a low lignin content. The fiber particles may be selected based on the need to achieve sufficient tensile strength for the formed sheet relative to a low inclusion rate, for example, an inclusion rate of approximately 2 percent to 15 percent. In an alternative embodiment, fibers such as plant fibers, including hemp and bamboo, may be used either in conjunction with the aforementioned fiber particles or as an alternative to them.

Aerosol formers included in the slurry forming the formed sheet or used in other aerosol-forming tobacco substrates may be selected based on one or more characteristics. Functionally, the aerosol former provides a mechanism that enables its vaporization and delivery of nicotine, flavoring, or both into the aerosol when heated to a temperature above the specific vaporization temperature of the aerosol former. Different aerosol formers typically vaporize at different temperatures. The aerosol former may be any suitable known compound or mixture of compounds that, when used, promotes the formation of a dense and stable aerosol and is substantially resistant to thermal degradation at the operating temperature of the induction heating device with which the inductively heated tobacco substrate will be used. An aerosol forming substance may be selected based on its ability to, for example, remain stable at or near room temperature but be capable of evaporating at a higher temperature, such as from 40 degrees Celsius to 450 degrees Celsius.

An aerosol-forming substance may also have humectant-like properties that help maintain the desired moisture level in the aerosol-forming substrate, particularly when the substrate consists of a tobacco-based product, particularly one containing tobacco particles. Specifically, some aerosol-forming substances are hygroscopic materials that function as humectants—in other words, materials that help maintain the humectant-containing tobacco substrate moist.

One or more aerosol-forming substances can be combined to achieve an advantage based on one or more properties of the combined aerosol-forming substances. For example, triacetin can be combined with glycerin and water to achieve an advantage based on the triacetin's ability to transport active components and the moisturizing properties of glycerin.

Aerosol forming substances may be selected from: polyols, glycol ethers, polyol ester, esters and fatty acids, and may contain one or more of the following compounds: glycerin, erythritol, 1,3-butylene glycol, tetraethylene glycol, triethylene glycol, triethyl citrate, propylene carbonate, ethyl laurate, triacetin, meso-erythritol, diacetin-based mixture, diethyl suberate, triethyl citrate, benzyl benzoate, benzyl phenyl acetate, ethyl vanillate, tributyrin, lauryl acetate, lauric acid, myristic acid and propylene glycol.

The aerosol-forming substrate may contain other additives and ingredients, such as flavorings. The aerosol-forming substrate preferably contains nicotine and at least one aerosol-forming substance.

The aerosol generating articles of the present invention may be in the form of combustible filter cigarettes or other smoking articles in which tobacco material is combusted to produce smoke.

Preferably, the aerosol-generating article may be substantially cylindrical in shape. The aerosol-generating article may be substantially elongated. The aerosol-generating article may have a length and a circumference substantially perpendicular to the length. The aerosol-generating article may have an overall length ranging from approximately 30 millimeters to approximately 100 millimeters. The aerosol-generating article may have an outer diameter ranging from approximately 5 millimeters to approximately 12 millimeters.

The present invention is defined in the claims. However, a non-exhaustive list of non-limiting examples is provided below. Any one or more features of these examples may be combined with any one or more features of another example, embodiment, or aspect described herein.

Example 1: A testing device for quality control of rod-shaped products, comprising:

a drum comprising a plurality of sockets, each socket of said plurality being configured to receive a rod-shaped article, the drum defining an outer surface;

an inductive sensor located at a socket from said plurality, wherein the inductive sensor comprises a coil that defines an internal volume large enough to accommodate the end of the rod-shaped article, wherein the inductive sensor is configured to record a characteristic of the current collector in the rod-shaped article;

wherein the coil comprises a first half-coil and a second half-coil, wherein the first half-coil and the second half-coil are configured to move from a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a coil in which current can flow, to a second operating position, in which the first half-coil and the second half-coil are separated from each other, and vice versa;

wherein the first half-coil is located below the outer surface of the drum, and the second half-coil is located above the outer surface of the drum; and

an actuator configured to move the first half-coil and the second half-coil from the first operating position to the second operating position and vice versa.

Example 2: A testing device according to example 1, comprising a control unit configured to command the actuator to move the first half-coil or the second half-coil from the second working position to the first working position when the rod-shaped article is in the socket.

Example 3: A testing device according to example 1 or 2, wherein the socket comprises a receiving surface, a part of the outer surface of the drum, and wherein the first half-coil is located under the receiving surface of the socket.

Example 4: A testing device according to one or more of examples 1-3, wherein the outer surface of the drum comprises one or more conductive strips that allow the second half-coil to be moved towards and away from the first half-coil and creates the possibility of an electrical connection between the first half-coil and the second half-coil.

Example 5: A testing device according to one or more of examples 1-4, wherein the actuator is a pneumatic actuator.

Example 6: The testing device according to the example comprises 5, in which the pneumatic actuator pusher is attached to the second half-coil.

Example 7: A testing device according to one or more of examples 1-6, wherein the coil defines a coil axis, and wherein the movement of the first half-coil and the second half-coil from the first operating position to the second operating position and vice versa is a linear movement.

Example 8: A testing device according to example 7, wherein said linear movement is a movement in a direction parallel to the axis of the coil.

Example 9: A testing device according to example 7 or 8, wherein said linear movement is a linear movement parallel to the axis of the socket.

Example 10: A testing device according to one or more of examples 1-9, comprising a control unit connected for data exchange with an inductive sensor, wherein the control unit is configured to receive signals from the inductive sensor associated with the specified characteristic of the current collector.

Example 11: A testing device for quality control of rod-shaped products, comprising:

a drum containing a plurality of sockets, wherein each socket of said plurality is configured to receive a rod-shaped article;

an inductive sensor located at a socket from said plurality, wherein the inductive sensor comprises a coil that defines an internal volume large enough to accommodate the end of the rod-shaped article, wherein the inductive sensor is configured to record a characteristic of the current collector in the rod-shaped article;

a compressed air system aligned with said socket of said plurality;

an actuator configured to activate a compressed air system so that it blows air when the rod-shaped article is located in the socket, to push the rod-shaped article into the reel.

Example 12: A testing device according to example 11, wherein said socket defines a socket axis and the compressed air system includes a nozzle configured to discharge a stream of compressed air substantially parallel to the socket axis.

Example 13: A testing device according to one or more of examples 1-12, wherein the drum has an axis of rotation, and each socket of said plurality defines a socket axis, wherein said longitudinal axis and said socket axis are parallel to each other.

Example 14: A testing device according to one or more of examples 1-13, wherein the coil has a coil axis, and each socket of said plurality defines a socket axis, wherein the coil axis and the socket axis are parallel to each other.

Example 15: A testing device according to one or more of examples 1-14, wherein the length of the coil is in the range from 20 millimetres to 40 millimetres.

Example 16: A testing device according to one or more of examples 1-15, comprising a control unit electrically connected to the inductive sensor, wherein the control unit is configured to receive a signal from the inductive sensor and compare this signal with a threshold.

Example 17: A testing device according to one or more of examples 1-16, wherein the specified characteristic of the current collector is the length of the current collector.

Example 18: A testing device according to example 16 or 17, wherein the control unit is configured to calculate the length of a current collector located in a rod-shaped article.

Example 19: An inspection device according to one or more of examples 1-18, comprising a rejection device configured to reject rod-shaped products based on a signal emitted by an inductive sensor.

Example 20: A testing device according to one or more of examples 1-19, wherein the drum comprises a plurality of inductive sensors, one sensor for each slot of said plurality of slots.

Example 21: A testing device according to one or more of examples 1-20, wherein the coil has a diameter ranging from 10 millimetres to 20 millimetres.

Example 22: A testing device according to one or more of examples 1-21, wherein each socket of said plurality defines a socket axis, wherein the socket axes are parallel to each other.

Example 23: A set containing:

a rod-shaped article containing a current collector;

a testing device according to one or more of examples 1-22.

Example 24: A kit according to example 23, wherein the rod-shaped article comprises a component of the aerosol-generating article.

Example 25: A kit according to example 23 or 24, wherein the current collector is in contact with the aerosol-forming material.

Example 26: A kit according to example 25, wherein the aerosol-forming material comprises tobacco material.

Example 27: A testing device comprising:

a first drum comprising a first plurality of sockets, wherein each socket of the first plurality is configured to receive a rod-shaped article, wherein the first drum defines a first outer surface;

a first inductive sensor positioned at a socket from said first plurality, wherein the first inductive sensor comprises a first coil defining an internal volume large enough to accommodate the first end of the rod-shaped article, wherein the first inductive sensor is configured to record a characteristic of the first current collector in the rod-shaped article;

wherein the first coil comprises a first half-coil and a second half-coil, wherein the first half-coil and the second half-coil are configured to move from a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a first coil in which current can flow, to a second operating position, in which the first half-coil and the second half-coil are separated from each other, and vice versa;

wherein the first half-coil is located under the first outer surface of the first drum, and the second half-coil is located above the first outer surface of the first drum;

a first actuator configured to move the first half-coil and the second half-coil of the first coil from the first operating position to the second operating position and vice versa in the first drum;

a second drum comprising a second plurality of sockets, each socket of the second plurality being configured to receive a rod-shaped article, the second drum defining a second outer surface;

a second inductive sensor located at the socket from the said second plurality, wherein the second inductive sensor comprises a second coil defining an internal volume large enough to accommodate the second end of the rod-shaped article, wherein the second inductive sensor is configured to record a characteristic of the second current collector in the rod-shaped article;

wherein the second coil comprises a first half-coil and a second half-coil, wherein the first half-coil and the second half-coil are configured to move from a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a second coil in which current can flow, to a second operating position, in which the first half-coil and the second half-coil are separated from each other and current cannot flow, and vice versa;

wherein the first half-coil of the second coil is located under the second outer surface, and the second half-coil of the second coil is located above the second outer surface;

a second actuator configured to move the first half-coil and the second half-coil of the second coil from the first working position to the second working position and vice versa in the second drum;

wherein the first drum and the second drum pass essentially tangentially to each other, ensuring the possibility of transferring the said rod-shaped product from the first drum to the second drum.

Example 29: A testing device comprising:

a first drum comprising a first plurality of sockets, wherein each socket of the first plurality is configured to receive a rod-shaped article;

a first inductive sensor located at a socket from said first plurality, wherein the first inductive sensor comprises a first coil defining an internal volume large enough to accommodate the first end of the rod-shaped article, wherein the first inductive sensor is configured to record a characteristic of the first current collector in the rod-shaped article;

a first compressed air system aligned with said socket of said first plurality;

a first actuator configured to activate a first compressed air system so that it blows air when the rod-shaped article is located in the socket of the first plurality, to push it into the first coil of the first drum;

a second drum containing a second plurality of sockets, wherein each socket of the second plurality is configured to receive a rod-shaped article;

a second inductive sensor positioned at the socket from said second plurality, wherein the second inductive sensor comprises a second coil defining an internal volume large enough to accommodate the second end of the rod-shaped article, wherein the second inductive sensor is configured to record a characteristic of the second current collector in the rod-shaped article;

a second compressed air system aligned with said socket of the second plurality;

a second actuator configured to activate a second compressed air system so that it blows air when the rod-shaped article is located in the socket of the second plurality, to push it into the second coil of the second drum;

wherein the first drum and the second drum pass essentially tangentially to each other, ensuring the possibility of transferring the said rod-shaped product from the first drum to the second drum.

Example 30: An apparatus for producing aerosol-generating articles comprising a rod-shaped element comprising a current collector, wherein said apparatus comprises a testing device according to any of examples 1-29.

Example 31: The apparatus according to example 30, wherein the rod-shaped element comprises an aerosol-forming material.

Example 32: A method for testing rod-shaped products, comprising:

ensuring the availability of a device for testing in accordance with examples 1-10;

positioning the rod-shaped product in the drum socket, wherein the first half-coil and the second half-coil are in the second working position;

moving the first half-coil and the second half-coil to the first working position;

registration of the characteristics of the current collector.

Example 33: Method of testing rod-shaped products, including:

ensuring the availability of a device for testing in accordance with examples 11-22;

positioning the rod-shaped product in the drum socket;

pushing the said rod-shaped article into the coil by means of an air flow;

registration of the characteristics of the current collector.

Below, the examples will be further described with reference to graphic materials, which:

Fig. 1 is a schematic isometric view, partially in section, of a rod-shaped article containing a current collector to be tested in accordance with the present invention;

Fig. 2 is a side sectional view of the rod-shaped article shown in Fig. 1;

Fig. 3 is a schematic isometric view of the testing apparatus according to the first embodiment of the present invention in a first configuration;

Fig. 4 is a schematic isometric view of a testing apparatus according to a second embodiment of the present invention;

Fig. 5 is a schematic top view of the testing apparatus shown in Fig. 4, in time sequence;

Fig. 6 is a sequence of operation steps of the inductive sensor present in the testing device according to the present invention;

Fig. 7 is a detailed sectional view of the coil of the testing device shown in Fig. 3, 4 or 5;

Fig. 8 is a front view of the coil shown in Fig. 7;

Fig. 9 is a side view of another embodiment of said rod-shaped article to be tested in accordance with the present invention;

Fig. 10 is a third embodiment of the testing device according to the present invention;

Fig. 11 and 12 are two enlarged views of the two parts shown in Fig. 10, in two different embodiments; and

Fig. 13 and Fig. 14 are two sectional views of the coil of the first embodiment of the testing device shown in Fig. 3, in the first and second operating positions, respectively.

Let us first turn to Figs. 1 and 2, where a rod-shaped product is shown, designated as a whole by the number 60.

Preferably, the rod-shaped article 60 comprises several components of the aerosol generating article, for example the aerosol generating article in its entirety.

The aerosol-generating article 60 comprises, for example, a plurality of elements assembled in the form of a rod. The said plurality of elements may include a plug element 11 (rod), an aerosol-forming substrate 10 in the form of a plug (rod) made of tobacco, a current-collecting material 12 located inside the aerosol-forming substrate 10, a hollow acetate tube 16, an additional hollow acetate tube 18, a mouthpiece 2, and an outer wrapper 22. The aerosol-generating article 60 comprises a mouthpiece end 24 and a distal end 26. The rod-shaped article 60 defines a longitudinal axis 61.

Preferably, the plurality of elements listed above extend along the longitudinal axis 61 of said rod-shaped article 60 one after the other. Preferably, they all have the same diameter.

Preferably, the cross-section of said rod-shaped article 60 along a plane perpendicular to its longitudinal axis 61 is a circle.

The rod-shaped article 60 comprises an outer surface 13, preferably substantially cylindrical, which extends along a longitudinal axis 61. The longitudinal axis 61 of said rod-shaped article 60 may correspond to the axis of the cylinder.

The aerosol-forming substrate 10 may comprise homogenized tobacco material.

The current collector 12 is preferably in thermal contact with the aerosol-forming substrate 10 such that, upon inductive heating of the current collector, heat is transferred to the aerosol-forming substrate 10, resulting in the release of the aerosol. Preferably, the current collector 12 is completely surrounded by the tobacco material that forms the aerosol-forming substrate 10.

As shown in the example presented in Fig. 1 and 2, the current collector 12 is completely contained in the rod-shaped article 60, more preferably it is completely contained in the aerosol-forming substrate 10.

Current collector 12 is made of a conductive material. Preferably, the current collector is made of metal and, in some embodiments, is made of a ferromagnetic material.

According to preferred embodiments, as shown in Figs. 1 and 2, the current collector 12 is strip-shaped. Alternatively, it may be rod-shaped. Its thickness preferably ranges from 30 micrometers to 60 micrometers. The length of the current collector preferably ranges from 5 millimeters to 20 millimeters.

Fig. 3 shows a portion of a preferred embodiment of the drum 4 of the inspection device 100 in accordance with the first aspect of the present invention.

For purposes of clarity, the testing device 100 is only partially shown in Fig. 3.

As will be apparent from the following description, the testing device 100 is designed to control the quality of the rod-shaped articles 60, and in particular the current collector 12.

The quality control provided by the testing device 100 may involve checking either the presence, integrity, or exact position of the current collector 12, as well as other characteristics of the latter.

As a non-limiting example, such characteristics may include one or more of the following: the length of the current collector, the thickness of the current collector, the deviation of the current collector from a straight line, the deviation of the axis of the current collector from parallel with the longitudinal axis 61 of said rod-shaped article 60, the electromagnetic properties of the current collector.

Quality control can also be performed at any stage of the aerosol-generating article manufacturing process. This means that the rod-shaped article 60 can be inspected when the aerosol-generating substrate 10 is attached to the filter element 2 of the mouthpiece portion or another component attached thereto, or the aerosol-generating substrate 10, which contains the current collector 12, can be inspected separately.

Referring again to Fig. 3, the drum 4 comprises a plurality of sockets 41, each of which is adapted to receive a rod-shaped article 60. The sockets 41 are preferably located on the outer surface 40 of the drum 4. Preferably, there are from about 20 to about 60 sockets 41 in the drum 4, preferably about 40.

In some embodiments, the drum 4 has a cylindrical shape and preferably the outer surface 40 on which the sockets 41 are located corresponds to the side surface of the cylinder.

It is obvious that the sockets 41 are preferably made with dimensions and shape that allow them to receive, at least partially, the rod-shaped article 60. Preferably, the dimensions and shapes of the sockets 41 are selected in such a way that each of them can receive the rod-shaped article 60. In a more general sense, quality control preferably includes positioning the rod-shaped article 60 in one of the sockets 41.

Positioning of said rod-shaped product 60 can be carried out either by using a suitable positioning device, not shown in the drawings, or by transferring the rod-shaped product 60 in any suitable manner, for example from another drum or conveyor.

In some embodiments, the testing device 100 may be included in an installation for producing aerosol-generating articles, and the rod-shaped article 60 may be transferred to the testing device 100 from a conveyor element of said installation.

Preferably, the drum 4 is a rotating drum having an axis 67 of rotation. Accordingly, the drum 4 allows the rod-shaped article 60 to be transferred from a first position to a second position, preferably forming an entry position where it is positioned in the socket, and an exit position where it is removed from the socket. The first position and the second position (not shown in Figure 3) are separated by an angular rotation of the drum.

In some embodiments, the sockets 41 may be elongated and thus define a corresponding socket axis 42. Preferably, the axis 42 of the socket 41 and the axis of rotation 67 are parallel to each other. Preferably, all axes 42 of the plurality of sockets 41 are parallel to each other.

The sockets 41 are preferably formed on the outer surface 40 of the drum 4. The sockets 41 may have the form of recesses formed in the outer surface 40 of the drum 4.

However, it is obvious that the sockets 41 may be defined by other elements on the outer surface of the drum 4, for example attached to it and protruding radially from it.

Preferably, drum 4 defines a front surface 64 and a rear surface (not visible in the figures). The rear surface is axially opposite to front surface 64.

In some embodiments, the sockets 41 extend from the front surface 64 to the rear surface, i.e., the sockets may be formed with opposite open ends.

In this way, the rod-shaped article 60 can be positioned in the socket 41 by approaching it from the side, preferably by sliding it along the direction determined by the axis 42 of the socket.

As shown in the embodiment shown in Fig. 3, the sockets 41 may have a length at least equal to the length of said rod-shaped article 60 to be inspected. Longer sockets 41 may also be used, allowing said rod-shaped article 60 to be inserted into them.

In some embodiments, the axis of rotation 67 of the drum 4 is substantially horizontal.

The sockets 41 can be designed in such a way that the rod-shaped article 60 is released from the socket 41 when it reaches a certain angular position along the axis of rotation 67, in which gravity acts on the rod-shaped articles 60, releasing them from the drum 4.

The testing device 100 further comprises an inductive sensor 5 located at least at one of said plurality of sockets 41. It is understood that although the embodiment shown in Fig. 3 represents a single inductive sensor 5 located at a specific socket 41, each socket 41 of the drum 4 may comprise a corresponding inductive sensor 5.

Also, in accordance with other possible embodiments, the inductive sensors 5 can be located on selected sockets 41, for example at a given angular distance.

Preferably, the inductive sensor 5 comprises a coil 51 defining an internal volume 50 that is large enough to accommodate the end of said rod-shaped article 60.

Fig. 7 and 8 show a coil 51 in accordance with a preferred embodiment.

Preferably, the coil 51 defines the coil axis 70 and has an internal diameter 71 ranging from 10 millimeters to 18 millimeters, and more preferably ranging from 12 millimeters to 16 millimeters. Preferably, the internal diameter 71 of the coil 51 is 14 millimeters.

It is understood that the above diameters are chosen in such a way as to make the coil 51 wide enough to accommodate the mouthpiece end 24 or the distal end 26 of the rod-shaped article 60, but at the same time to avoid the use of bulky elements in the testing device 100.

In some embodiments, the length of the coil 51 is adapted to completely accommodate the rod-shaped article 60.

Preferably, the length of the coil 72 is in the range of 20 millimeters to 40 millimeters, more preferably in the range of 25 millimeters to 35 millimeters. Preferably, the length of the coil 72 is 32 millimeters.

In some embodiments, coil 51 is formed by a pair of wound wires.

Preferably, the coil 51 comprises a number of total turns lying in the range from 26 to 46. More preferably, the number of turns lies in the range from 30 to 42. Preferably, the number of turns is 32.

In case the coil 51 is formed by a pair of wires, each wire may contain half of the total number of turns indicated above.

The coil 51 is preferably cylindrical in shape. Preferably, the coil 51 is positioned in the socket such that the axis 70 of the coil is parallel to the axis 42 of the socket.

The presence of the current collector 12 in the rod-shaped article 60 can be determined by moving the rod-shaped article 60 relative to the coil 51 and by detecting a change in the feedback signal generated by the interaction between the current collector 12 and the coil 51.

For this purpose, in some embodiments, as shown in Fig. 3, the testing device 100 comprises a control unit 7 electrically connected to the inductive sensor 5 and configured to receive a signal from said inductive sensor 5 and compare it with a threshold to determine a change in the signal generated by the presence of the current collector 12.

It is clear that such a change in the signal can be caused either by moving the coil 51 relative to the rod-shaped article 60 as in the example shown in Fig. 3, or by moving the rod-shaped article 60 relative to the coil 51, as in the embodiment shown in Fig. 4 or Fig. 5.

In general, it is clear that the inductive sensor 5 can create an alternating magnetic field in the coil 51, which changes when the current collector 12 passes through it. In a more general sense, the inductive sensor 5 is configured to create an alternating magnetic signal in the detection direction, preferably corresponding to the axis 70 of the coil 51.

Preferably, the magnetic field generated by the inductive sensor 5 changes when the first end 24, 26 of said rod-shaped article 60, in which the current collector 12 should be located, is placed in the internal volume 50 of the coil 51 of the inductive sensor 5.

In other words, the magnetic field created by the passage of the current collector 12 through the internal volume 50 of the inductive sensor 5 counteracts the magnetic field created by the sensor 5, that is, the coil 51. According to Lenz's law, the current collector 12 acts as a resistance in the coil 51 or, more generally, in the inductive sensor 5.

In more detail, when a ferromagnetic material enters a field, an electromagnetic force (Maxwell-Faraday's law) is generated within it, which creates alternating eddy currents. This alternating current creates an induced magnetic field (Maxwell-Ampère's law), which is opposite to the magnetic field of the sensor (Lenz's law).

Accordingly, the presence or absence of current collector 12 in rod-shaped article 60 can be determined based on this expected behavior in a magnetic field. If no change occurs when rod-shaped article 60 passes through the alternating magnetic field generated by coil 51, then current collector 12 is likely not present in rod-shaped article 60.

Otherwise, the change can be determined by calculating the impedance of said rod-shaped article 60, which changes when the current collector 12 passes through the internal volume 50 of the coil 51, as explained earlier.

According to preferred embodiments, the feedback signal generated as the current collector 12 passes through the internal volume 50 may be used to determine other characteristics of the current collector 12.

Referring to Fig. 6, a possible use of the feedback signal may be to determine the length of the current collector 12.

Fig. 6 shows how the equivalent resistance of the “coil and current collector” system changes in accordance with the relative position of the current collector 12 in the internal volume 50.

At first, when the rod-shaped article 60 has not yet entered the internal volume 50, the feedback signal output by the inductive sensor 5 does not change.

When the rod-shaped product 60 enters the internal volume 50, a change in the feedback signal occurs.

The feedback signal reaches a minimum level when the entire current collector 12 has completely entered the internal volume 50, and begins to decrease when the end of the current collector 12 leaves the coil 51.

Comparison of this signal with the positions of the rod-shaped article 60 in the internal volume 50 makes it possible to determine the length of the current collector 12.

Preferably, the length of the current collector 12 is estimated in accordance with the peak of the measured equivalent resistance, determined after appropriate calibration.

In an alternative embodiment, the impedance parametric function exhibits a maximum rather than a minimum when the current collector is fully inserted into the coil.

In such embodiments, the coil 51 or, more generally, the internal volume 50 of the inductive sensor 5 is longer than the expected length of the current collector 12, also in accordance with the previously mentioned characteristics of the coil.

Preferably, the length of the coil 51 is selected such that it exceeds the expected length of the current collector 12 by at least 10 millimeters on each side in order to avoid distortion of the magnetic field at the end of the coil.

According to preferred embodiments, the control unit 7 is configured to determine whether the length of the current collector 12 corresponds to the expected value by checking the change in the feedback signal in accordance with the position of the said rod-shaped article 60 in the internal volume 50.

It is clear that the control unit 7 can be configured to calculate the length of the current collector 12 located in the rod-shaped article 60, also in accordance with other methods, for example, taking into account the generally different characteristic behavior of the inductive sensor 5 during the interaction of the said rod-shaped article 1 with the internal volume 50.

In a more general sense, the equivalent resistance of the feedback signal may be an indicator of the nature, conformity with the shape requirements, or composition of the current collector 12. Accordingly, additional characteristics of the current collector 12 may be determined by the testing device 100 according to the present invention.

In order to introduce the rod-shaped article 60 into the coil 51 in the testing device 100 shown in Fig. 3, the coil 51 is divided into two half-coils 65 and 66. The first half-coil 66 is located under the outer surface 40 of the drum 4, and the first half-coil is located above the outer surface 40 of the drum. The two half-coils 65, 66 can be moved from the first working position shown in Fig. 13, in which they form the coil 51. In this first working position, the above-described measurements can be carried out, performed by the inductive sensor and shown, for example, in Fig. 6. The second working position, shown in Fig. 3 and 13: the second half-coil 65 moves along the axis 70 of the coil and is removed from the first half-coil in such a way that the rod-shaped product 60 can be located in the socket 41. The movement is carried out using the actuator 6, connected to the control unit 7.

In the testing device 100 according to Fig. 3, 13 and 14, during operation, the rod-shaped articles 60 are inserted into the sockets 41. When the rod-shaped articles are positioned in the sockets, the first half-coil 66 and the second half-coil 65 are in the second working position, that is, the two half-coils 65, 66 are separated from each other, as shown in Fig. 3 and 14. When the rod-shaped article 60 is in the socket, the first half-coil 66 and the second half-coil 65 move to the first working position shown in Fig. 13, so that a measurement can be carried out by the inductive sensor 5. The relative movement of the first half-coil and the second half-coil is carried out as follows: the first half-coil 66 is positioned under the outer surface 40 and is fixed relative to it, and the second half-coil 65 moves back and forth from the first working position shown in Fig. 14, into the second working position shown in Fig. 3 and 14, and vice versa. The shift of the second half-coil 65 from the first working position to the second working position and vice versa is carried out by means of a pusher 69 connected to the actuator 6. The pusher 69 is attached to the second half-coil with the possibility of moving it linearly in the direction towards the first half-coil and away from it, as shown by arrow 68 in Fig. 3.

In another embodiment, which is shown in Fig. 4 and 5, instead of moving the coil relative to the rod-shaped article, as in the embodiment shown in Fig. 3, 13 and 14, the said rod-shaped article 60 is moved relative to the coil 51. In the testing device 200, reference numbers identical to those indicated in the testing device 100 are used to identify the same elements. In the device 200, the inductive sensor 5 includes a coil 51, which in this case is connected to the outer surface 40 of the drum 4. The coil 51 (better visible in Fig. 7 and 8) is located, for example, at one end of the socket 41. The testing device 200 includes a compressed air system 8, 9, containing a compressed air generator 9 and a gun 8 for ejecting a stream of compressed air. The gun can eject a stream of compressed air in a direction substantially parallel to the axis 42 of the socket and, accordingly, parallel to the longitudinal axis of the rod-shaped article 60. The gun can be located on one side of the drum 4 and can be stationary, i.e., it does not rotate with the drum. In this case, a single compressed air system can be used for all the sockets 41. During rotation, when the rod-shaped article passes in front of the gun 8, a stream of compressed air is ejected, which pushes the rod-shaped article 60 into the coil 51, and the above-described measurements can be carried out using the inductive sensor 5. This is shown in Fig. 5, which shows a series of "state snapshots" taken at successive time intervals. In the far left corner of the figure, the rod-shaped article 60 is inserted into the socket 41. During subsequent rotation, the socket with the rod-shaped article 60 passes in front of the gun 8, and a stream of compressed air is ejected along the direction 83 by the gun 8. Then, the rod-shaped article 60 is pushed into the coil 51 (see the following state pictures from left to right in the figure up to the dotted line 64).

The dotted line 84 divides Fig. 5 into two. The second part to the right of the dotted line 84 in Fig. 5 is an image of the state several time intervals after the left part (see details below).

The inspection device 100, 200 according to the present invention may also comprise a rejection device (schematically shown in the right part of Fig. 5 as a rectangle 82) configured to reject rod-shaped products 60 that lack a susceptor 12 or that contain a susceptor 12 that does not meet the expected characteristics. As explained earlier, rod-shaped products 60 can be rejected based on the output signal of the inductive sensor 5 in accordance with the calculation or determination made by the control unit 7, which is advantageous. As shown in the right part of Fig. 5, for example, the function of the rejection device 82 is to hold the rod-shaped product 60, which is defective, in the drum 4, while the proper rod-shaped products 60 are transferred to other drums (not shown) to continue processing.

The rod-shaped articles 600 may also comprise a first current collector 12 and a second current collector 121, as shown in Fig. 9. The rod-shaped articles 600 essentially include two rod-shaped articles 60 according to the embodiment shown in Figs. 1 and 2.

In case the rod-shaped article 600 comprises more than one current collector, a testing device according to the third embodiment of the present invention is preferably provided, such as the testing device 300 shown in Fig. 10.

The testing device 300 includes two or more testing drums 4, at least a first drum and a second drum, each of which contains a coil 51. The first drum or the second drum are identical to the drum 4, which can be made either in accordance with the first embodiment shown in Fig. 3 and 13-14, or with the second embodiment shown in Fig. 4 or 5. However, the drums are preferably of the same type, i.e. either correspond to the first embodiment of the testing device 100, or correspond to the second embodiment of the testing device 200.

The first drum 4 is configured to test the first current collector 12 of said rod-shaped article 600, and the second drum 4 is configured to test the second current collector 121 of said rod-shaped article 600. For example, if the first drum and the second drum correspond to the second embodiment shown in Fig. 4 and 5, in the first drum the compressed air system is located on the first side surface of the drum, and in the second drum the compressed air system is located on the second side surface of the second drum.

From the first drum, after checking the first current collector 12, the rod-shaped article 600 is transferred to the second drum, as shown in Figs. 11 and 12. The first drum and the second drum are essentially tangential to each other. The gap between the first drum and the second drum is such that the rod-shaped article 600 can be inserted between them. The transfer occurs between the seat of the first drum and the seat of the second drum.

Fig. 11 shows a transfer between two reels 4 in accordance with the embodiment shown in Fig. 3, 13, 14. Fig. 12 shows a transfer between two reels 4 in accordance with the second embodiment shown in Fig. 4, 5.

For the purposes of this description and the appended claims, except where otherwise indicated, all numbers expressing quantities, amounts, percentages, etc., are to be understood as modified in all instances by the term "about." Furthermore, all ranges include the disclosed maximum and minimum points and any intermediate ranges therebetween, which may or may not be specifically listed herein. Therefore, in this context, the number A is to be understood as A+10 percent of A. In this context, the number A may be considered to include numerical values that are within the normal standard error for measuring the property that the number A represents. The number A, in some instances, when used in the appended claims, may deviate by the percentages listed above, provided that the amount by which A deviates does not materially affect the essential and novel characteristic(s) of the claimed invention. Furthermore, all ranges include the disclosed maximum and minimum points and any intermediate ranges therebetween, which may or may not be specifically listed herein.

Claims (52)

1. A testing device for quality control of rod-shaped products, comprising: a drum defining an outer surface and containing a plurality of nests, each of which is configured to receive a rod-shaped article; an inductive sensor located at a socket of a plurality of sockets, containing a coil that determines an internal volume sufficient to accommodate the end of a rod-shaped article therein, wherein the inductive sensor is configured to perceive a characteristic of a susceptor in the rod-shaped article; the coil comprises a first half-coil and a second half-coil, wherein the first half-coil and the second half-coil are configured to move from a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a coil with the possibility of current flowing in it, to a second operating position, in which the first half-coil and the second half-coil are separated from each other, and vice versa; wherein the first half-coil is located below the outer surface of the drum, and the second half-coil is located above the outer surface of the drum; and an actuator configured to move the first half-coil and the second half-coil from the first operating position to the second operating position and vice versa. 2. The device according to claim 1, comprising a control unit configured to control an actuator for moving the first half-coil or the second half-coil from the second working position to the first working position when the rod-shaped product is in the socket. 3. A device according to any one of paragraphs 1, 2, in which the socket comprises a receiving surface, a part of the outer surface of the drum, and the first half-coil is located under the receiving surface of the socket. 4. A testing device for quality control of rod-shaped products, comprising: a drum containing a plurality of sockets, each of which is configured to receive a rod-shaped article; an inductive sensor located at a socket of a plurality of sockets, wherein the inductive sensor comprises a coil that determines an internal volume sufficient to accommodate the end of a rod-shaped article therein, wherein the inductive sensor is configured to perceive a characteristic of a susceptor in the rod-shaped article; a compressed air system aligned with a nest of multiple nests; an actuator configured to activate a compressed air system to blow air out of it when a rod-shaped article is positioned in a socket for pushing the rod-shaped article into the coil. 5. A device according to any one of the preceding claims, wherein the drum has an axis of rotation, and each socket of the plurality of sockets defines a longitudinal axis, and the longitudinal axis and the axis of rotation are parallel to each other. 6. A device according to any of the preceding claims, wherein the length of the coil is in the range of from 20 millimetres to 40 millimetres. 7. A device according to any one of the preceding claims, comprising a control unit electrically connected to an inductive sensor, wherein the control unit is configured to receive a signal from the inductive sensor and to compare this signal with a threshold value. 8. The device according to claim 7, wherein the control unit is configured to calculate the length of the susceptor located in the rod-shaped product. 9. A device according to any one of the preceding claims, comprising a rejection device adapted to reject rod-shaped articles based on a signal emitted by an inductive sensor. 10. A device according to any one of the preceding claims, wherein the drum comprises a plurality of inductive sensors, a sensor for each socket of the plurality of sockets. 11. A device according to any of the preceding claims, wherein the socket defines a socket axis and the coil defines a coil axis, wherein the coil axis and the socket axis are parallel to each other. 12. A testing device for quality control of rod-shaped products, comprising: a first drum defining a first outer surface and containing a first plurality of sockets, wherein each socket of the first plurality of sockets is configured to receive a rod-shaped article; a first inductive sensor located at a socket of a first plurality of sockets, wherein the first inductive sensor comprises a first coil defining an internal volume sufficient to accommodate the first end of the rod-shaped article therein, wherein the first inductive sensor is configured to perceive a characteristic of the first susceptor in the rod-shaped article; wherein the first coil comprises a first half-coil and a second half-coil, wherein the first half-coil and the second half-coil are configured to move from a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a first coil with the possibility of current flowing in it, to a second operating position, in which the first half-coil and the second half-coil are separated from each other, and vice versa; the first half-coil is located under the first outer surface of the first drum, and the second half-coil is located above the first outer surface of the first drum; a first actuator configured to move the first half-coil and the second half-coil of the first coil from the first operating position to the second operating position and vice versa in the first drum; a second drum defining a second outer surface and containing a second plurality of sockets, wherein each socket of the second plurality of sockets is configured to receive a rod-shaped article; a second inductive sensor located at a socket of a second plurality of sockets, wherein the second inductive sensor comprises a second coil that determines an internal volume sufficient to accommodate the second end of the rod-shaped article therein, wherein the second inductive sensor is configured to perceive the characteristic of the second susceptor in the rod-shaped article; the second coil comprises a first half-coil and a second half-coil, wherein the first half-coil and the second half-coil are configured to move from a first operating position, in which the first half-coil and the second half-coil are in contact with each other to form a second coil with the possibility of current flowing in it, to a second operating position, in which the first half-coil and the second half-coil are separated from each other, and vice versa; wherein the first half-coil of the second coil is located under the second outer surface, and the second half-coil of the second coil is located above the second outer surface; a second actuator configured to move the first half-coil and the second half-coil of the second coil from the first working position to the second working position and vice versa in the second drum; wherein the first drum and the second drum are located close to each other to ensure the transfer of the rod-shaped product from the first drum to the second drum. 13. A testing device for quality control of rod-shaped products, comprising: a first drum comprising a first plurality of sockets, wherein each socket of the first plurality of sockets is configured to receive a rod-shaped article; a first inductive sensor located at a socket of a first plurality of sockets, wherein the first inductive sensor comprises a first coil defining an internal volume sufficient to accommodate the first end of the rod-shaped article therein, wherein the first inductive sensor is configured to perceive a characteristic of the first susceptor in the rod-shaped article; a first compressed air system aligned with a socket of the first plurality of sockets; a first actuator configured to activate the first compressed air system to blow air out of it when the rod-shaped article is positioned in the socket of the first plurality of sockets for pushing the rod-shaped article into the first coil; a second drum comprising a second plurality of sockets, wherein each socket of the second plurality of sockets is configured to receive a rod-shaped article; a second inductive sensor located at a socket of a second plurality of sockets, wherein the second inductive sensor comprises a second coil that determines an internal volume sufficient to accommodate the second end of the rod-shaped article therein, wherein the second inductive sensor is configured to perceive the characteristic of the second susceptor in the rod-shaped article; a second compressed air system aligned with a socket of the second plurality of sockets; a second actuator configured to activate a second compressed air system to blow air out of it when the rod-shaped article is positioned in a socket from a second plurality of sockets for pushing the rod-shaped article into the second coil of the second drum; wherein the first drum and the second drum are located close to each other, ensuring the possibility of transferring the rod-shaped product from the first drum to the second drum. 14. A method for testing rod-shaped products, including: providing a testing device according to any of paragraphs 1-3, 5-11; the placement of the rod-shaped product in the drum socket, wherein the first half-coil and the second half-coil are in the second working position; moving the first half-coil and the second half-coil to the first working position; and perception of the characteristics of the susceptor. 15. A method for testing rod-shaped products, including: providing a device for testing according to any of paragraphs 4-11; placement of the rod-shaped product in the drum socket; pushing a rod-shaped article into the coil by a stream of air; and perception of the characteristics of the susceptor.