DE102023105753A1 - Transport device for transporting containers - Google Patents

Abstract

The invention relates to a transport device for transporting containers, in particular beverage containers, along a transport path with a carrier (1) having a plurality of container receptacles arranged in the circumferential direction (U), which can be driven in rotation via a drive device (4). According to the invention, the drive device (4) is an electric drive designed as a direct motor.

Description

The present invention relates to a transport device for transporting containers along a transport path with a carrier having a plurality of container receptacles arranged in the circumferential direction, which can be driven rotatably via a drive device.

Such transport devices are generally known from the prior art, whereby the invention relates in particular but not exclusively to transport devices from the beverage industry. Accordingly, the containers are in particular beverage containers, which are designed, for example, as a bottle or as a can and serve to hold a filling medium, for example a beverage. Drinks bottles are usually made of glass or plastic, whereby plastic drinks bottles are usually formed in a stretch blow molding process.

For this purpose, so-called preforms are first provided which have a pre-formed head section which already has an external thread for receiving a closure cap. These preforms are made from a thermoplastic material, in particular polyethylene terephthalate (PET), and beverage bottles are formed from the preforms during stretch blow molding. For this purpose, the preforms are first fed to a heating device in which the preforms are heated to a predetermined temperature which weakens the material in such a way that it can be easily molded. The preforms are then fed to the actual blow molding device. This has a large number of blow molding stations arranged in the circumferential direction in which the preforms are arranged and transported along a transport path by rotation. The blow molding stations each have a blow mold which serves as a container holder and which has an inner contour formed as a negative of the bottle.

During transport, a fluid is blown into the preforms under pressure via a blowing unit, which presses the walls of the preforms against the blow mold, causing the preforms to take on the shape of a beverage bottle.

Such transport devices are known from the prior art, whereby in the case of blowing devices the individual blowing stations or the container receptacles are arranged on a rotatably driven carrier, which is usually driven by a separate drive device. This can be, for example, an electric motor which is arranged next to the rotatably driven carrier and whose axis of rotation is arranged parallel to the axis of rotation of the carrier. A gear device is usually arranged between the drive device and the rotatable carrier, which consists of one or more intermediate gears and which transmits the rotation of the drive device to the carrier. At the same time, the rotary movement can also be translated so that the optimal operating point of the electric motor can be adapted to the optimal operating point of the blowing device.

Such a design has proven itself in practice, whereby a relatively large design of the transport device is required in order to be able to arrange the individual components relative to one another, particularly in connection with the drive device. In addition, the large number of individual transmission units in the form of gears results in mechanical friction losses, so that part of the drive power cannot be used for the transport device.

Against this background, the object of the invention is to provide a transport device which is characterized by a compact design and efficient operation.

The subject matter and solution of this problem is a transport device according to claim 1. Accordingly, the invention provides that the drive device is an electric drive designed as a direct motor. In the context of the invention, a direct drive is understood to mean a design in which the carrier is directly connected to the drive device, so that the rotary movement of the drive device is identical to that of the carrier both in terms of speed and direction of rotation.

According to such an embodiment, the previously mentioned gear device can be dispensed with, so that a much more efficient operation of the transport device is possible with regard to friction losses.

In this context, it should be noted that the invention does not refer exclusively to transport devices that are part of a blowing device. Rather, such transport devices are used in a variety of treatment devices. For example, individual filling stations can also be arranged on the rotatably driven carrier, in which case, in the course of the movement of the The beverage containers are filled with a filling medium, in particular with a beverage, using a carrier. The labeling of beverage containers can also be carried out on a suitably designed, rotatably driven carrier. In addition, it is also conceivable that treatment is dispensed with entirely, so that the transport device is only intended for transporting the containers along a transport route.

According to a preferred embodiment of the invention, the carrier is formed on a rotor of the drive device or is supported on the rotor. According to a common embodiment of electric drives, a stator and a rotor are provided, the rotor representing the movable part of the drive device. The carrier is now connected to the rotor in such a way that the force acting in the axial direction from the carrier is completely absorbed by the rotor. In this context, an axial force is understood to mean a force that acts parallel to the axis of rotation of the carrier or the drive device. This requires that the drive device is designed in such a way that it can absorb as much force as possible, which is usually formed not only by the carrier but also by any treatment units.

The rotor must also have a certain diameter in order to be able to compensate for any tilting moments as effectively as possible. A design is therefore preferred in which the rotor has a disk-shaped design at least in sections, with the rotor then having a significantly larger diameter in this section than its axial extent. A design with a ratio between diameter and axial extent that is greater than 3:1, particularly preferably greater than 5:1 and most preferably greater than 10:1 is particularly preferred in this context.

In this context, a particularly preferred embodiment provides that the rotor initially has a diameter of between 300 and 6700 mm in sections. Accordingly, a section with a relatively large diameter is provided, with the stator then also preferably arranged on this section. Of course, it is also within the scope of the invention that the rotor has a corresponding diameter not only in sections but completely. The advantage of such an embodiment is that the interaction between the stator and rotor takes place at a large distance from the axis of rotation, so that the torque generated can be introduced particularly effectively. In addition, a large circumference is also provided, so that not only a drive torque but also a braking torque can be introduced effectively with the help of the drive device. This means that additional braking devices can be dispensed with, since the drive device alone can introduce a braking torque that stops the rotor in a short time, so that an emergency stop can also be brought about by the drive device alone. According to such an embodiment, no further devices for introducing a torque are then preferably arranged along the circumference of the rotor.

A preferred development of the invention further provides that the rotor has a plurality of first drive magnet elements arranged in the circumferential direction and a stator of the drive device has a plurality of second drive magnet elements arranged in the circumferential direction, wherein the first and second drive magnet elements face each other and each form first drive magnet element pairs. The first drive magnet elements can be permanent magnets, for example. The second drive magnet elements are preferably magnetic coils, wherein the magnetic coils then surround the stator in the circumferential direction. Of course, a reverse arrangement is also possible, wherein the first drive magnet elements are designed as magnetic coils and the second drive magnet elements as permanent magnets. The magnetic coils are supplied with current during operation and thereby generate a magnetic field which interacts with the permanent magnets. The drive magnet elements, which are designed as magnetic coils, can then be operated with an alternating electrical field. Such alternating fields are magnetic fields which change in strength and polarity, wherein the magnetic field follows the applied voltage with a time delay. This alternating field then pulls the first drive magnet elements with it and causes the rotor to rotate. The drive magnet elements can basically be arranged in different positions. For example, it is conceivable to arrange or form the first drive magnet elements on an outer circumference of the rotor and the second drive magnet elements on an inner circumference of the stator.

However, a configuration in which the first drive magnet elements are arranged on a front side of the rotor and the second drive elements are arranged axially below the rotor is particularly preferred. In particular, the first drive magnet elements are arranged on a lower front side of the rotor.

Such a design is particularly advantageous when it is necessary to position the rotor axially relative to the stator or a housing section of the transport device. For this purpose, the invention preferably provides a bearing device which supports the rotor, wherein this bearing device can be formed, for example, by plain bearings or roller bearings. However, a design in which the bearing device is designed as a magnetic bearing device is particularly preferred, so that the rotor is also supported by magnetic forces. Such a design has the advantage that the friction losses between the component parts supported against one another can be significantly reduced, so that a much more effective operation of the drive device is possible. This magnetic bearing device can, for example, be formed separately from the drive device on another section of the rotor and consist of at least one pair of bearing magnets which interact with one another, for example on one end face of the rotor. In addition, a pair of bearing magnets can also be arranged on both end faces of the rotor, so that the movement in the axial direction is limited on both sides.

If the drive magnet elements are arranged on the front side of the rotor, it is also possible to form the magnetic bearing device together with the drive device or to integrate the magnetic bearing device in the drive device. Thus, simply by generating a magnetic field through the drive magnet elements, the rotor and thus also the carrier can be raised in the axial direction, so that a gap is formed between the rotor and the stator. If the first drive magnet elements are then also operated with an alternating field, it is possible to implement not only the bearing but also the drive solely via the first and second drive magnet elements. In addition, a pair of drive magnet elements with a first and a second drive magnet element can be provided on both front sides. However, it is also sufficient if only one pair of bearing magnets is provided on one front side. In particular, this is the upper front side.

Regardless of the specific design of the magnetic bearing device, a bearing control device is always preferably provided which is designed to set a gap with a predefined distance between the first and the second drive magnet elements during operation. In addition, it can also be provided that the stator surrounds the rotor in sections not only on a lower but also on an upper end face in order to be able to determine a movement of the rotor. The gap required for the bearing is then continuously regulated via the bearing control device, since certain weight fluctuations on the rotor always have to be compensated for, particularly when receiving containers or in the case of a filling device by receiving a filling medium in the containers. By adjusting the magnetic field, a predefined distance can then be continuously regulated. The predefined distance is preferably between 0.1 and 10 mm.

In addition, the bearing control device can also be integrated in a control device, since in particular - as already explained above - the drive of the rotor and its magnetic bearing can be realized exclusively via the first and second drive magnet elements.

Since in the case of a magnetic bearing the gap required for the bearing is only created after a magnetic field is introduced, it may be necessary to provide additional support for the rotor, especially in the event of an emergency shutdown of the power. An emergency bearing is preferably provided for this purpose. This is preferably arranged below the rotor and can be implemented, for example, using a roller or a running skid. Alternatively, it is also possible to provide a type of sliding bearing. This can be achieved, for example, by choosing the materials that slide against each other. The introduction of a sliding film is also conceivable in this context.

A further development of the invention provides that the rotatable carrier is mounted in the radial direction via a magnetic guide device. Although a certain degree of self-centering of the rotor occurs in the case of drive magnet elements arranged on the front side, it may still be necessary to provide an additional radial bearing for centering the rotor. This is also preferably achieved via a magnetic guide device, with the magnetic guide device then being formed in particular from guide magnet elements facing each other coaxially. The first guide magnet elements are then formed on an outer circumference of the rotor and the second guide magnet elements on an inner circumference of the stator. The guide magnet elements are preferably designed as permanent magnets, although the invention is not limited to this, and it is also conceivable for individual guide magnet elements to be designed as magnetic coils.

If the drive magnet elements are already arranged on an outer circumference of the rotor or on an inner circumference of the stator, an additional magnetic guide device is not required. In this context, However, an additional magnetic bearing device is then required, since support in the radial direction via the drive magnet elements is not possible.

The invention further relates to a treatment device for treating containers, in particular beverage containers, with a transport device according to the invention and at least one treatment unit arranged along the transport path.

The treatment unit can, for example, be a filling unit for filling the containers or a labeling unit for labeling the containers.

However, a particularly preferred embodiment is one in which the treatment unit is designed as a blow molding unit and the container receptacles are designed as a blow mold. The container in the form of a preform is then arranged in the blow mold and subjected to a blowing medium, in particular compressed air.

Preferably, several treatment units are provided in the circumferential direction, wherein at least three, particularly preferably at least five, very preferably at least eight treatment units are arranged in the circumferential direction.

The invention further relates to a method for operating a transport device according to the invention or a treatment device according to the invention, wherein the drive device for driving the rotor generates an alternating magnetic field in the rotor or in the stator.

A further development of the method provides that the bearing device for supporting the rotor creates a gap between the rotor and stator by generating a magnetic field. In particular, a distance is created between the first and second drive magnet elements. This distance can also be regulated via the bearing control device. In particular, it is provided that the bearing control device regulates a predefined distance between 0.1 and 10 mm during operation, regardless of the load acting on the rotor.

In addition, the method provides that the alternating magnetic field provided for driving simultaneously creates the magnetic field for supporting the rotor, so that the driving and bearing of the rotor can be achieved by the alternating field alone.

A further development of the method also provides that the containers are treated at least in sections during transport and the transport route. This treatment can, for example, consist of containers being filled with a filling medium within the container receptacles or being provided with a label. However, containers in the form of preforms are particularly preferably formed into beverage containers. In particular, the beverage containers are beverage bottles. This can be done, for example, by simple blow molding. However, so-called stretch blow molding is particularly preferred, whereby in addition to the introduction of compressed air, a stretch rod is also moved in the axial direction and stretches the containers in the form of preforms along the axis.

• 1 eine Transportvorrichtung gemäß dem Stand der Technik,
• 2 eine erfindungsgemäße Transportvorrichtung und
• 3 eine Detailansicht der Transportvorrichtung gemäß 2
• 4 eine alternative Transportvorrichtung gemäß 3

The invention is explained below using an exemplary embodiment. Shown are:

• 1 a transport device according to the state of the art,
• 2 a transport device according to the invention and
• 3 a detailed view of the transport device according to 2
• 4 an alternative transport device according to 3

The 1 shows a generic transport device with a rotatably driven carrier 1, which has a plurality of stations 2 arranged in the circumferential direction, at which container holders (not shown in detail, e.g. blow molds) can be arranged. By incorporating treatment units, the transport device can be part of a treatment device, with containers in particular being transported in the transport device.

The transport takes place by rotating the carrier 1 about an axis of rotation D. For this purpose, the carrier 1 is arranged on a gear 3, wherein the carrier 1 and the gear 3 have an identical axis of rotation D.

In addition, a drive device 4 in the form of an electric drive is provided, which rotatably drives the gear wheel 3 and thus also the carrier 1 via a gear unit 5.

Based on the 1 It can be seen that the drive device 4 is arranged next to the rotatably driven carrier 1, so that the drive device 4 and the carrier 1 have axes of rotation D offset parallel to one another.

In addition, two braking devices 6 are provided along the circumference of the gear 3, which brake the gear 3 and thus also the carrier 1 by introducing a braking torque tes can be braked. In this respect, the driving and braking of the carrier 1 takes place via separate devices which are arranged offset from one another along the circumference of the gear wheel 3. The two braking devices 6 are offset from one another by 180°, for example.

The 2 now shows a transport device according to the invention, wherein in particular the design of the carrier 1 is identical to that in the 1 transport device shown.

In contrast to 1 However, the carrier 1 is supported directly on a rotor 7 of the drive device 4, the rotor 7 and the carrier 1 having an identical axis of rotation D. In addition, there is no gear unit 5 between the rotor 7 and the carrier 1, so that the rotary movement caused by the rotor 7 acts directly on the carrier 1. Accordingly, the rotor 7 is part of a drive device 4, which is designed as a direct motor.

The rotor 7 is disc-shaped and has a diameter between 300 and 6700 mm.

In addition, a stator 8 with a C-shaped cross section is provided, which surrounds the rotor 7 at least in sections on an outer circumference and which is designed to drive the rotor 7.

The exact training will be determined in particular based on the 3 clearly. Accordingly, the rotor 7 has a plurality of first lower drive magnet elements 9a arranged in the circumferential direction U and the stator 8 has a plurality of second lower drive magnet elements 9b arranged in the circumferential direction U. The first drive magnet elements 9a are arranged on the front side on a lower side of the rotor 7 and are located directly opposite the second drive magnet elements 9b.

The first drive magnet elements 9a are furthermore designed as permanent magnets and the second drive magnet elements 9b as magnetic coils, wherein these second drive magnet elements 9b are operated with an alternating magnetic field, which on the one hand causes a gap 10 between the rotor 7 and the stator 8 in an axial direction running parallel to the axis of rotation D and at the same time generates a drive torque in the rotor 7.

The gap 10 preferably has a distance between 0.1 and 10 mm and is continuously regulated via a bearing control device (not shown in detail). Accordingly, the drive magnet elements 9a, 9b are not only part of the drive device 4, but rather also part of a bearing device, wherein the bearing device and the drive device 4 are combined with one another and wherein the bearing control device can be part of a control device of the drive device 4.

In addition, guide magnet elements 11a, 11b are provided on an outer circumference of the rotor 7 and on an inner circumference of the stator 8, which are arranged coaxially to one another and face one another, wherein first guide magnet elements 11a are arranged on the rotor 7 and second guide magnet elements 11b are arranged on the stator 8 and which cause a centering of the rotor 7 by generating a magnetic field.

In addition, the rotor 7 can also have an emergency running bearing (not shown in detail), which provides certain emergency running properties in the event of a power failure.

The 4 shows an alternative embodiment in which additionally upper guide magnet elements 12a, 12b are provided on an upper end face of the rotor.

List of reference symbols:

1

carrier

2

Stations

3

gear

4

Drive system

5

Gear unit

6

Braking device

7

rotor

8

C-shaped stator

9a

first drive magnet elements

9b

second drive magnet elements

10

gap

11a

lateral first guide magnet elements

11b

lateral second guide magnet elements

12a

upper first guide magnet elements

12b

upper second guide magnet elements

D

Rotation axis

U

Circumferential direction

Claims (16)

Transport device for transporting containers, in particular beverage containers, along a transport path with a carrier (1) having a plurality of container receptacles arranged in the circumferential direction (U), which can be driven rotatably via a drive device (4), characterized in that the drive device (4) is an electric drive designed as a direct motor. Transport device according to Claim 1 , characterized in that the carrier (1) is formed on a rotor (7) of the drive device (7) or is completely supported on the rotor (7). Transport device according to Claim 2 , characterized in that the rotor (7) has at least in sections a diameter between 300 and 6700 mm. Transport device according to Claim 2 or 3 , characterized in that the rotor (7) has a plurality of first drive magnet elements (9a) arranged in the circumferential direction (U) and a stator (8) of the drive device (4) has a plurality of second drive magnet elements (9b) arranged in the circumferential direction (U), wherein the first and the second drive magnet elements (9a, 9b) face each other. Transport device according to Claim 4 , characterized in that the second drive magnet elements (9b) are designed as magnetic coils. Transport device according to one of the preceding claims, characterized in that a magnetic bearing device is provided for axially supporting the rotor (7). Transport device according to one of the Claims 4 until 6 , characterized in that the first drive magnet elements (9a) are arranged on an end face of the rotor (7) and the second drive magnet elements (9b) are arranged in the axial direction below the rotor (7) on the stator (8). Transport device according to Claim 6 or 7 , characterized in that a bearing control device is arranged to set a gap (10) with a predefined distance between the first and the second drive magnet elements (9a, 9b) during operation. Transport device according to Claim 8 , characterized in that the predefined distance is between 0.1 and 10 mm. Transport device according to one of the Claims 6 until 9 , characterized in that the rotor (7) has an emergency running bearing. Transport device according to one of the preceding claims, characterized in that the rotatable carrier (1) is mounted in the radial direction via a magnetic guide device. Transport device according to Claim 11 , characterized in that the magnetic guide device is formed from coaxially facing guide magnet elements (11a, 11b). Treatment device for treating containers, in particular beverage containers, with a transport device according to one of the preceding claims and at least one treatment unit arranged along the transport path. Treatment device according to Claim 13 , characterized in that the treatment unit is designed as a blow molding station. Method for operating a transport device according to one of the Claims 1 until 12 or a treatment device according to Claim 13 or 14 , wherein the drive device (4) generates an alternating magnetic field in the rotor (7) or in the stator (8) for driving the rotor (7). Procedure according to Claim 15 , wherein the bearing device for supporting the rotor (7) creates a gap (10) between the rotor (7) and the stator (8) by generating a magnetic field.