WO2001083299A1 - Machine for metering and filling liquid or pasty products - Google Patents

Abstract

The invention concerns a machine for metering and filling liquid or pasty products, such as food products, comprising product supply means (13), means for metering (14) said product and means for filling (15) said product into containers (11) arranged in a continuous transport line (12). The metering means (14) comprise actuators provided on either side of a gate valve, whereof the pistons operate alternately in pair such that one of the actuators fills up while the other one is emptied. The chambers of said actuators are alternately communicated with the supply means (13) and the filling means (15) through the gate valve which pivots between two alternating positions. Finally, the machine comprises automatic hydraulic means for cleaning the gate valve and the pistons, comprising means for moving the gate valve and the pistons into a cleaning position, wherein cleaning and rinsing solutions are injected into the circuits of the fluid passage. Said solutions flow in different ways around the gate valve and the pistons and eliminate product particles lodged therein.

Description

DOSING AND FILLING MACHINE FOR LIQUID OR PASTY PRODUCTS

Technical Field The present invention relates to a machine for dosing and filling liquid or pasty products, in particular food products, comprising means for supplying filling product, means for dosing said pasty product and means for filling said product formed. at least one filling duct, the metering means comprising at least one actuator comprising a piston arranged to alternately pump a dose of product from the supply means and discharge it into the filling means, and a plug arranged alternately pump and evacuate said dose of product.

Prior art

There are currently different types of metering machines using cylinders whose volume of the chamber defines the volume of the product to be metered. Such machines are for example described in the French patent applications published under the numbers 2 613 782 and 2 639 066. There are also machines whose jacks are equipped with a hydraulic barrier as described in particular in the book "Design of machines, Principles and applications "by Georges Spinnler, published by" Presses polytechniques et universitaire romandes "(p.196).

There are also machines using two jacks working in opposition so that one of the jacks is filled while the other is emptied. The chambers of the jacks are alternately placed in communication with supply means and filling means by means of a ball valve pivoting between two alternating positions. This type of plug can also include zones of reduced section so as to allow the passage of a fluid forming a hydraulic barrier. The hydraulic barrier is used to carry particles of product to be dosed during the use of the machine. However, after a certain period of use, it is necessary to clean all of the parts of the machine in contact with the product to be dosed, and in particular the jacks and the plug. In current machines, these parts must be dismantled and washed manually, respecting very strict hygienic conditions. This implies a high cost of maintenance and use and a relatively long downtime of the machine.

Statement of the invention

The present invention proposes to overcome these drawbacks by providing a dosing and filling machine also arranged to constantly check its state of cleanliness, and which allows automatic cleaning, without disassembly of the parts in contact with the product to be dosed.

This object is achieved by a machine as defined in the preamble and characterized in that it comprises means for automatic cleaning of said means for dosing the filling product.

In a preferred embodiment, the means for cleaning the machine comprise means for moving the plug and the piston into a cleaning position.

Advantageously, the piston is provided with two seals separated by a zone of reduced section allowing the passage of a fluid between the two seals, and the jack comprises a cylinder provided with at least two grooves of fluid passage spaced the same distance as the piston seals.

Preferably, the actuator further comprises a seal integral with the cylinder, and the three seals define two hydraulic barriers each limited by two adjacent seals. The displacement means are advantageously arranged to place the two movable seals facing the fluid passage grooves.

According to an alternative embodiment, the machine may comprise at least one pair of jacks arranged on either side of the plug, each jack comprising at least two grooves for the passage of fluid.

In all embodiments, the plug comprises at least one distribution groove surrounded by two evacuation grooves, and the displacement means are arranged to put said evacuation grooves in communication with at least one fluid inlet hole .

Preferably, the plug further comprises at least two fluid passage grooves disposed opposite one of said fluid inlet holes. It also includes several identical modules, and at least one of the fluid passages is common to two modules.

In all the embodiments, the machine includes means for analyzing the fluid.

Brief description of the drawings

The present invention and its advantages will be better described with reference to a particular embodiment of the invention and to the accompanying drawings in which:

FIG. 1 is an overall view, partially in section, of a machine according to the present invention,

FIG. 2a is a sectional view of part of the machine of FIG. 1, in the working position, FIG. 2b is a view similar to FIG. 2a, in the cleaning position,

FIG. 3a is a sectional view of another part of the machine of FIG. 1, in the working position, and

Figure 3b is a view similar to Figure 3a, in the cleaning position.

With reference to FIG. 1, the dosing and filling machine 10 is designed to deliver doses of liquid or pasty products, in particular food products, and fill, in particular at high rates and without deterioration of the product, containers 11, for example in the form of pots, arranged on a continuous transport line 12.

The machine described here is intended for a transport line 12 with four tracks. The containers 11 are distributed regularly on these tracks in rows of four.

This machine 10 mainly comprises means 13 for supplying the filling product, metering means 14 for said product and means 15 for filling the containers 11 with a dose of product. In addition, the machine 10 comprises means for automatic or semi-automatic cleaning of all of its parts in contact with the filling product to be metered, and in particular metering means 14.

The supply means 13 comprise a tank 20 containing the filling product to be dosed, for example liquid cheese. The tank 20 has a bottom 21 in which are formed four supply conduits 22. These four supply conduits 22, each corresponding to a container transport track 11, serve to take the product from the bottom 21 of the tank 20 and to bring it to the metering means 14, shown in detail in FIGS. 2 and 3. These metering means 14 comprise a ball valve, illustrated in more detail in FIGS. 2a, 2b and 3a, 3b, formed by a distribution body 30 and a valve 35 oriented along an axis perpendicular to the direction of the transport line 12. The body 30 is crossed by a cylindrical bore 31. It further comprises, in its upper part, four inlet mouths 32 each communicating with a supply conduit 22 and, in its lower part, four mouths outlet 33 aligned, which are each respectively arranged opposite an inlet mouth 32. These outlet mouths 33 open into the bore 31. They are connected to four flexible filling conduits 16 forming part of the filling means and allowing to simultaneously fill with a dose of product four containers 11 of the same row transported by the four tracks.

As illustrated by FIGS. 2a and 2b, the distribution body 30 of the ball valve comprises, on a downstream lateral part relative to the transport line 12, four downstream pumping orifices 34av aligned, each orifice being arranged in a plane containing a pair of inlet / outlet mouths 32, 33, and on an upstream lateral part, four upstream pumping ports 34am aligned, each one being arranged symmetrically, with respect to the vertical plane, to a downstream pumping port 34av . These eight pumping orifices 34av, 34am each open into the bore 31.

The cylindrical plug 35 is rotatably mounted inside the bore 31. This plug comprises for the four groups of inlet / outlet mouths 32, 33 - pumping orifices 34av, 34am, each corresponding to a transport track of containers 11, four pairs of downstream / upstream distribution grooves 36av, 36am semicircular, formed diametrically opposite the periphery of the plug 35. These pairs of grooves 36av, 36am are regularly arranged along the plug 35 so that the distance between the grooves 36av, 36am of two adjacent pairs is equal to the distance between the inlet / outlet mouths 32, 33 - orifices of pumping 34av, 34am from two adjacent groups. During metering and filling, the valve 35 is placed axially inside the bore 31 in a working position in which the distribution grooves 36av, 36am of the four pairs are respectively in correspondence of the inlet / outlet mouths 32, 33 - pumping ports 34av, 34am of the four groups.

The plug 35 is coupled to rotation drive means, for example a servomotor which is arranged to rotate it alternately between two symmetrical positions with respect to the transverse vertical plane of the dispensing body. In its first position, as shown in FIG. 2a, the four upstream grooves 36am put the four inlet mouths 32 into communication with the four upstream pumping orifices 34am, and the four downstream grooves 36av put the four orifices into communication. downstream pumping 34av with the four outlet mouths 33. Conversely, when the plug 35 is in its second position (not shown), the four upstream grooves 36am put the four upstream pumping ports 34am into communication with the four outlet mouths 33, and the four downstream grooves 36av put the four inlet mouths 32 into communication with the four downstream pumping orifices 34av.

The plug 35 has four pairs of left / right circular evacuation grooves 37g, 37d (FIGS. 3a and 3b) relative to the direction of movement of the containers 11 on the transport line 12, which are formed at the periphery of the plug 35 , regularly along its length. The evacuation grooves 37g, 37d, of each pair are arranged symmetrically on either side of a pair of corresponding distribution grooves 36av, 36am. The distribution body 30 also comprises, in its lower part, four pairs of left / right outlet holes 38g, 38d aligned, opening into the bore 31. The outlet holes 38g, 38d of each pair are symmetrically arranged. on either side of a corresponding outlet mouth 33, at a distance approximately equal to the distance between the distribution grooves 36av, 36am and the left / right drainage grooves 37g, 37d of the same group. In the working position of the plug 35 (FIG. 3a), the eight evacuation grooves 37g, 37d communicate with the eight evacuation holes 38g, 38d.

The plug 35 furthermore five circular hydraulic passage grooves 39, formed at its periphery, regularly along its length. These five grooves 39 are arranged in such a way that the distance between two adjacent passage grooves 39 is equal to the distance between the distribution grooves 36av, 36am of two adjacent pairs, and that two adjacent passage grooves 39 are arranged symmetrically apart. and other distribution grooves 36av, 36am of a pair. With this arrangement, each evacuation groove 37g, 37d is placed midway between a pair of distribution grooves 36av, 36am and a passage groove 39.

The distribution body 30 also has, in its upper part, five fluid inlet holes 40, aligned and distributed regularly along its length, which open into the bore 31, and in its lower part, five fluid outlet holes 41 aligned, in correspondence with the fluid inlet holes 40. The distance between two adjacent fluid inlet / outlet holes 40, 41 is equal to the distance between two adjacent passage grooves 39, two inlet holes / adjacent fluid outlet 40, 41 being arranged symmetrically on either side of an inlet / outlet mouth 32, 33. In the working position of the plug 35, the fluid inlet / outlet holes 40, 41 communicate with the five passage grooves 39, which are arranged opposite. These fluid inlet / outlet holes 40, 41 are connected to a fluid supply circuit of the automatic cleaning means of the machine 10.

During dosing and filling, the fluid supply circuit circulates fluid in the five fluid passage grooves 39 of the plug 35, which delimit four product distribution modules, corresponding to the four container transport tracks 11. This fluid forms a double hydraulic protection barrier around each module. This double barrier optimally protects the product to be dosed against external impurities. Furthermore, the double hydraulic barrier forces the particles of product escaping from the distribution grooves 36am, 36av to pass through the evacuation grooves 37g, 37d. These particles are eliminated by the evacuation holes 38g, 38d of the fluid circuit.

The pressure of this fluid circuit is chosen to be lower than the pressure of the product at the level of the plug 35 to prevent protective fluid from infiltrating the distribution grooves. Preferably, a vacuum is generated at the evacuation holes 38g, 38d so that any leaks of product and / or protective fluid are evacuated efficiently and quickly.

Two static seals 42 are also provided at the ends of the bore 31 in order to obtain its tightness with the plug 35 on both sides of the distribution body 30.

The fluid supply circuit is moreover provided with means for controlling the degree of soiling of the fluid disposed at the outlet of the five discharge holes 38g, 38d. These means make it possible to detect an anomaly, for example a product leak in the fluid circuit, and to determine the opportune moment to carry out an automatic or semi-automatic cleaning of the dispenser.

The metering means 14 further comprise, for each of the four distribution modules, two upstream / downstream cylinders 50am, 50av mounted in opposition. The four upstream cylinders 50am are fixed on the distribution body 30 facing the four upstream pumping holes 34am and the four downstream cylinders 50av are fixed on the body 30 facing the four downstream pumping holes 34av. Each cylinder 50am, 50av comprises a cylinder 51 am, 51 av provided with a bore 52am, 52av opening into the body 30 and defining a suction / ejection orifice 53am, 53av opposite the pumping orifice 34am, 34av. A piston 54am, 54av is slidably mounted in the bore 52am, 52av and defines therewith a metering chamber 55am, 55av delimited by the piston and the suction / ejection orifice 53am, 53av. A piston rod 56am, 56av, integral with the piston 54am, 54av, on the side opposite to the metering chamber 55am, 55av, makes it possible to control, by means of an actuator, the axial displacement of the piston in the bore 52am, 52av .

During dosing, the piston rod 56am, 56av alternately moves the piston 54am, 54av between two retracted and extended positions, defining the volume of the dosing chamber 55am, 55av. The stroke of the piston 54am, 54av is adapted as a function of the dose of product required.

The two upstream 54am and downstream 54av pistons of each distribution module work in opposition. When one of the pistons 54am is in communication with the inlet mouth 32 of the product from the tank 20, it is filled with a dose of product while the other piston 54av is in communication with the outlet mouth 33 of the product and empties into the filling duct 16 to fill a container 11. The machine synchronizes the work in opposition to the suction / ejection pistons and the adjustment of the alternate position of the plug 35.

The piston 54am, 54av of each cylinder 50am, 50av includes a reduced section area 57am, 57av and two seals 58am, 58av, of the O-ring type, in contact with bore 52am, 52av, which surround the reduced section area . The cylinder 51 am, 51 av has two circular hydraulic passage grooves 59am, 59av, formed inside the bore 52am, 52av, each being in communication with a fluid supply circuit via holes d fluid inlet / outlet arranged radially at through the cylinder 51 am, 51 av. The distance between the two seals 58am, 58av is equal to the distance between the two hydraulic passage grooves 59am, 59av and is greater than the stroke of the piston 54am, 54av between its retracted and extended positions.

During dosing, the two seals 58am, 58av are always arranged on either side of the hydraulic passage groove 59am, 59av, on the side corresponding to the dosing chamber 55am, 55av, without ever entering it. this. Consequently, the seal 58am, 58av, on the side of the piston rod 56am, 56av, is always disposed between the two grooves 59am, 59av.

A static seal 60am, 60av is provided in the bore 52am, 52av at the end of the cylinder 51 am, 51 av, beyond the groove 59am, 59av outside to seal between the piston rod and the bore.

The fluid supply circuit introduces fluid into the two fluid passage grooves 59am, 59av. The fluid flows on the one hand between the two movable seals 58am, 58av, around the reduced section area 57am, 57av, and on the other hand, between the movable seal 58am, 58av outside and the seal static 60am, 60av. These two fluid flows define two successive hydraulic protective barriers, which protect the product to be dosed against external impurities and evacuate the particles of product escaping from the metering chamber 55am, 55av.

The machine 10 also includes means for controlling the degree of soiling of the fluid flowing in these fluid supply circuits.

The means for controlling the degree of soiling of the fluids indicate the moment when the state of cleanliness of the fluid supply circuits of the machine 10, namely of the plug valve 35 and / or of the two rows of jacks 50am, 50av, is insufficient. Machine 10 then stops dosing and filling and goes into automatic cleaning mode during which all the parts of the machine in contact with the product, in particular the valve 35 and the cylinders 50am, 50av, are cleaned, without dismantling the parts, by means of automatic cleaning means. It is also possible to interrupt the operation of the machine manually and to start a cleaning cycle, for example after a given period of use.

The cleaning means comprise means for axial displacement of the plug 35, such as for example an actuator, and pistons 54am, 54av, in this case the piston rods 56am, 56av, in a cleaning position.

With reference to FIGS. 2b and 3b which illustrate the machine in the cleaning position, the actuator moves the plug 35 to the left to put it in its cleaning position and the piston rods 56am, 56av retract the pistons 54am, 54av au- beyond the extended position to also put them in their cleaning position.

When the plug 35 is in its cleaning position, the four left evacuation grooves 37g are in communication, but slightly offset to the right, of the four fluid inlet / outlet holes 40, 41, from the end left of the body 30. The four right evacuation grooves 37d as well as the four pairs of downstream / upstream distribution grooves 36av, 36am are then in communication with the four pairs of inlet / outlet mouths 32, 33, which have for this a sufficiently large passage section.

When the pistons 54am, 54av are in their cleaning position, the two mobile seals 58am, 58av are housed in the two hydraulic passage grooves 59am, 59av of the bores 52am, 52av of the cylinders 51 am, 51 av. Cleaning and rinsing solutions are then injected into the fluid supply circuits, normally acting as a hydraulic barrier, as well as into the supply tank 20, normally used to supply the product.

The cleaning and rinsing solutions circulate in the four left grooves 37g of the plug 35 and remove the particles of product therein. The solutions injected into the tank 20 circulate therefrom in the four right evacuation grooves 37d as well as in the four pairs of downstream / upstream distribution grooves 36av, 36am, and therefore in the four pairs of metering chambers 55am, 55av opposite, and are discharged through the four outlet mouths 33 to the filling conduits 16. This allows, on the one hand, to remove the particles of food product located in the four right discharge grooves 37d of the plug 35 and, on the other hand, mainly to completely wash the entire circuit normally used by the product during dosing and filling.

Similarly, the rinsing and washing solutions injected into the grooves 59am, 59av of the eight cylinders 50am, 50av remove the particles of product found on the movable seals 58am, 58av, the piston rods 56am, 56av and pistons 54am, 54av, bores 52am, 52av and also metering chambers 55am, 55av.

The eight cylinders 50am, 50av and the plug 35 are then returned to their working positions. The five hydraulic passage grooves 39 of the plug 35 are again in communication with the fluid supply circuit and are washed automatically in turn by the cleaning and rinsing solutions.

The present invention has many advantages. The alternating work of the upstream 50am and downstream 50av cylinders means that the rate of dosing by cylinder is equal to half the filling rate of the containers 11. Even with high filling rates, the mechanical stresses applied to the product during dosing are limited. As a result, the machine is well suited to dosing and filling certain delicate food products for which too strong a pressure can deteriorate the structure and therefore modify the consistency or appearance and make them unsuitable for sale. Furthermore, the jacks 50am of the upstream row can be controlled in displacement separately from the jacks 50av of the downstream row. Thus, the suction and ejection times of a dose of product can be different, which makes it possible to better adapt to the consistency of the product and to the speed of the machine.

Each distribution module and each cylinder has a double hydraulic protection barrier during use of the machine. This double barrier optimally protects the product to be dosed against external impurities. This characteristic makes it possible to dose more delicate products and more sensitive to contamination. Furthermore, the double barrier makes it possible to carry, via the fluid supply circuit, particles of product escaping from the normal circuit. This prolongs the state of cleanliness of the parts in contact with the product, when using the machine.

The cylinders 50am of the upstream row and the cylinders 50av of the downstream row can be connected to two separate fluid supply circuits, also separate from the fluid supply circuit of the body of the distributor, this in order to limit the risks of fouling of the entire machine 10 in the event of anomalies in one of the circuits, for example a significant product leak in one of the circuits.

More particularly, this machine is designed with a permanent control of its state of cleanliness and an automatic cleaning without dismantling of the parts in contact with the product to be dosed, either when the machine is too dirty either when you want to fill the containers 11 with a different product.

The means for controlling the degree of soiling of the fluid circulating in the fluid supply circuits make it possible, on the one hand, to determine whether an anomaly has occurred in one of the circuits and, on the other hand, to define when to wash.

The automatic cleaning means of the machine are very efficient. Indeed, the particular arrangement of the fluid circuits and of the reduced cross-section areas on the plug 35 and on the pistons 55am, 55av, the mounting of double gasket on the jacks, the use of the axial displacement means for automatically putting the plug and the pistons in their cleaning position, and the use of the fluid circuits and of the tank for the circulation of cleaning and rinsing solutions, allow an automatic and complete washing of all the machine parts in contact with the product, without dismantling the machine or intervention by an operator. This allows the machine to be used quickly to dose and fill containers with a different product, directly after the automatic washing sequence. This also implies a relatively short downtime of the machine and very low maintenance and operating costs.

Claims

claims 1. Metering and filling machine for liquid or pasty products, in particular food products, comprising supply means (13) for filling product, metering means (14) for said pasty product and filling means (15 ) formed of at least one filling duct (16) of said product, the metering means (14) comprising at least one cylinder (50am, 50av) comprising a piston (54am, 54av) arranged to alternately pump a dose of product from supply means (13) and discharge it into the filling means (15), and a plug (35) arranged to alternately pump and discharge said dose of product, characterized in that it comprises means for automatic cleaning of said doses metering means (14) for the filling product. 2. Machine according to claim 1, characterized in that the cleaning means comprise means for moving the plug (35) and the piston (54am, 54av) of the jack (50am, 50av) in a cleaning position. 3. Machine according to claim 2, wherein the piston (54am, 54av) is provided with two seals (58am, 58av) separated by an area of reduced section (57am, 57av) allowing the passage of a fluid between the two seals, characterized in that the jack (50am, 50av) comprises a cylinder (51am, 51av) provided with at least two grooves for the passage of fluid (59am, 59av) spaced by the same distance as the seals seal (58am, 58av) of the piston. 4. Machine according to claim 3, characterized in that the cylinder (50av, 50am) further comprises a seal (60av, 60am) integral with the cylinder (51 av, 51 am), and in that the three seals sealing (58av, 58am, 60av, 60am) define two hydraulic barriers each limited by two adjacent seals. 5. Machine according to claim 2, characterized in that the displacement means are arranged to place the two seals (58av, 58am) movable opposite the grooves (59av, 59am) for fluid passage. 6. Machine according to claim 1, characterized in that it comprises at least one pair of jacks (50am, 50av) arranged on either side of the plug (35), each jack comprising at least two grooves (59av, 59am) of fluid passage. 7. Machine according to claim 1, characterized in that the plug (35) comprises at least one distribution groove (36av, 36am) surrounded by two discharge grooves (37d, 37g), and in that the displacement means are arranged to put said discharge grooves (37d, 37g) in communication with at least one hole (40) for fluid entry. 8. Machine according to claim 7, characterized in that the plug (35) further comprises at least two grooves (39) for fluid passage arranged opposite one of said fluid inlet holes (40). 9. Machine according to claim 7, characterized in that the plug (35) comprises several identical modules, and in that at least one of the fluid passages (39) is common to two modules. 10. Machine according to claims 3 or 8, characterized in that it comprises means for analyzing the fluid.