EP1361979A1

EP1361979A1 - Installation for the high-speed packaging of a liquid product

Info

Publication number: EP1361979A1
Application number: EP02704881A
Authority: EP
Inventors: Alain Petit
Original assignee: EMSI
Current assignee: EMSI
Priority date: 2001-02-22
Filing date: 2002-02-22
Publication date: 2003-11-19
Also published as: US20040154695A1; WO2002066327A1; FR2821068B1; FR2821068A1

Abstract

The invention relates to an installation for the high-speed packaging of a viscous or pasty liquid product, which may be loaded or not. The inventive installation is of the type that comprises a tank (4), the lower part of which is fitted with a check valve-type delivery means (6), through which flows doses of the product (P) obtained under the force of a pig (5) that can move vertically along a stroke path, or a series of stroke paths, of a given length by means of control elements. The pig (5) comprises a valve which, in coordination with the movement of the pig (5), can open and close in order for the tank (4) to be filled through said pig (5). The valve comprises an opening (50) which is disposed in the pig (5) and a check valve (51) that can be used to close the opening (50) from underneath when manoeuvred by means of a jack, the rod (52) of which passes through the pig (5) axially.

Description

INSTALLATION FOR HIGH-THROUGHPUT PACKAGING OF A LIQUID PRODUCT.

The present invention relates to an installation for the high-speed packaging of a liquid, viscous or pasty product, loaded or not, in containers which may be of different formats.

There is essentially only one type of installation allowing the high-speed packaging of liquid, viscous or pasty products, loaded or not, such as for example paints or the like. Such an installation comprises, in association with a transfer path on which the containers move step by step, a metering means capable of successively discharging a predetermined quantity of product into each of said containers.

The metering means comprises a hopper into which the liquid product to be packaged is poured, and which communicates with a chamber having a pourer below and in which a piston of horizontal axis acts. It also includes a valve device for closing the pourer and opening the hopper and vice versa, in association with the reciprocating movement of the piston, so as to carry out the following successive operations: opening the hopper and closing the pourer , retraction of the piston to suck the product from the hopper into the chamber, then closing of the hopper and opening of the pourer while the piston advances and pushes the product which escapes from said chamber through said pourer.

The amount of product is adjusted volumetrically, by modifying the piston stroke, by means of movable stops whose positioning is obtained by means of screw systems. Such an installation has many drawbacks, in particular in that it is of very complex design, which is essentially due to the fact that its basic concept is relatively old, and that the improvements which it has undergone have not modified said basic concept.

Furthermore, this installation has the other drawback of being of considerable bulk, in particular in that it occupies a large surface area on the ground, which is detrimental given that such an installation is associated with others upstream and downstream, such as for example an installation for capping containers and an installation for labeling them.

Document FR 2 684 087 also discloses a method and an installation for formulating and packaging a liquid product, which uses a packaging machine comprising a scraper piston capable of descending in a controlled manner in a removable tank. the bottom of which is equipped with a closable pouring means. The metering is also carried out volumetrically, by measuring the stroke of the piston.

This packaging machine is simpler in design than those mentioned above, however it is limited to small series, depending on the capacity of the tank.

Furthermore, most machines of this type must have a valve at the base of the tank fitted with an anti-drip device which often operates by capillary action and for this purpose comprises a plate of a certain thickness, pierced with '' a multiplicity of parallel channels of small section, through which the product to be dosed passes. Such an anti-drip device is entirely satisfactory from the operating point of view, however it is not very easy to clean, in particular with regard to the channels, which constitutes a disadvantage when switching from one product to another, which is often the case.

It is of course possible during a change of product, to replace an anti-drip device with another, to carry out cleaning, however, depending on the product dosed, cleaning can be long, and this requires, during succession small series, to have a large number of anti-drip devices.

Document US Pat. No. 5,524,683 also discloses a container filling device, of the pump type, comprising a chamber in which a piston provided with a valve can move, while the outlet of said chamber is closed by a second valve. By alternately opening and closing the valves, combined with the displacement of the piston, the formation of doses is obtained by filling and emptying the chamber. However, such a device is not very precise, in particular because of the valves used, it is for this reason that its use is limited to fluid and preferably pasty products, and that it cannot be used with liquid products.

Document US Pat. No. 4,767,031 also discloses a metering device for metering fluid or pasty masses and filling them with containers. It has a cylindrical chamber in which a metering piston can move by means of a hollow piston rod in which a dispensing drawer can move, in particular comprising a push rod interposed between two obturator pads.

The dosing device of this document, whatever the embodiment considered, is designed to deliver a dose to each round trip of the scraper piston, since the movement of the latter is coordinated with the movement of the drawer, which also ensures the obturation of the cylindrical chamber after release the dose. Consequently, this device is not intended to also be able to deliver doses by succession of strokes, as is the case with the machine of the document FR 2,684,087, previously cited.

Furthermore, the dose value is linked not only to the dimensional characteristics of the cylindrical chamber, but also to those of the drawer, so that the range of variation of the dose is narrow.

In addition, the drawer is of a relative tightness, so that the device is not intended for the dosing of liquid products, but is reserved for fluid and pasty products.

The aim of the present invention is to remedy the various aforementioned drawbacks, by proposing an installation for high-speed packaging for viscous or pasty products, but also for liquid products, loaded or not, in containers which may optionally be of different capacities, and which is also easy to maintain.

The installation for high-speed packaging of a liquid, viscous or pasty product, loaded or not, according to the invention is of the type comprising a tank equipped below with a valve-type pouring means equipped with a device anti-drip capable of letting doses of said product pass under the push of a scraper piston able to move vertically in a stroke, or a succession of strokes, of given length by means of control means, said scraper piston comprising a valve or the like capable, in coordination with the movement of said scraper piston, of opening and closing to allow filling of the tank through said scraper piston, and it is essentially characterized in that said valve comprises an opening formed in said scraper piston, and a valve capable of coming close from below said opening while being operated by means of a jack whose rod passes axially through said scraper piston.

When raising the piston, the valve opens to allow the tank to be filled, then closes before the start of the descent.

According to an additional characteristic of the installation according to the invention, the valve is of annular shape.

Therefore, of course, the opening in the scraper piston is also of annular shape. This shape is preferred to a classic round shape, in order to allow filling of the tank with greater precision.

Indeed, with a disc-shaped valve, depending on the rate of dosage and the nature of the product dosed, we observe when closing said valve, the formation by cavitation of an air pocket under the latter, so that you do not get the full filling of the tank. The annular shape of the valve allows the product to pass through, and thus prevents the formation of an air pocket.

According to another additional characteristic of the installation according to the invention, the valve is of a profile capable of promoting the circulation of the product in one direction as in the other depending on the movement in opening or closing of said valve.

According to a particular embodiment of the installation according to the invention, the valve is of section having on the side of the scraper piston a rounded profile, and on the other side an angle profile. According to another additional characteristic of the device according to the invention, the scraper piston has a concave underside.

The concavity of this lower face prevents the formation of an air pocket under the scraper piston, outside the valve.

According to a particular embodiment, the underside of the scraper piston has an inclined wall extending between the opening and the peripheral scraper lip.

According to another additional characteristic of the installation according to the invention, the anti-drip device is removable, and consists of the juxtaposition, face against face, of plates, held by a clamping means, and each having on at least l 'one of their two faces, ridges or the like, parallel, so that said faces, striated or not, cooperate to create parallel channels through which the product to be dosed can pass.

Advantageously, when it comes to cleaning the anti-drip device, it is easy to dismantle it, to disassemble the plates and to soak them in a suitable product, and possibly to brush them.

According to another additional characteristic of the installation according to the invention, the ridges have a V-shaped cross section.

According to another additional characteristic of the installation according to the invention, the means for controlling the length of the stroke of the scraper piston are associated with a means of weighing the containers being filled thereof, in order to allow a comparison and possible adjustment of the characteristics of said race. According to another additional characteristic of the installation according to the invention, the weighing means is integrated into a supply path on which the containers move step by step, at the rate of production of the doses of product.

The weighing means are not used permanently since this would result in a slowing down of the rate due to the time necessary for the stabilization of the weighing. They are used at the start of the filling process to check whether the quantity of product delivered corresponds to what has been calculated theoretically, so that the stroke of the scraper piston can be adjusted. Furthermore, the weighing means can allow verifications during the packaging process, and can, if necessary, make it possible to correct the displacement parameters of the scraper piston, due, for example, to a drop in tightness of this one, linked to its wear.

The advantages and characteristics of the installation according to the invention will emerge more clearly from the description which follows and which refers to the appended drawing, which represents a non-limiting embodiment thereof.

In the attached drawing:

Figures 1, 2 and 3 show schematic views of a high-speed packaging installation of a liquid product, during successive stages of its use.

Figure 4 shows a cross-sectional view of a particular embodiment of a part of the same installation.

FIG. 5 represents a view in axial half-section of a variant of the same embodiment. Figure 6 shows a cross-sectional view of another part of the same installation.

FIG. 7 represents a partial plan view on a larger scale of a part of the same part.

With reference to these figures 1, 2 and 3, an installation 1 can be seen for the high-speed packaging of a liquid product P, viscous or pasty, loaded or not, in containers C.

The installation 1 comprises a device 2 for metering and filling the containers C, as well as a device 3 for step by step arrangement, under the device 2, of the containers C.

The device 3 for arranging the containers C comprises a transfer belt 30 associated, vertically with the device 2 for metering and filling, with a weighing means 31.

The metering and filling device 2 essentially comprises a tubular tank 4, the bottom 40 of which is equipped with a pouring means 41 provided, in a manner known per se and not shown, with an anti-drip valve system.

The tank 4 is surmounted by a chamber 42 with a diameter greater than that of the tank 4, and into which opens a pipe 43 for supplying product P.

We can also see that the tank 4 is associated with a scraper piston 5, able to move vertically in order to push the product P in the tank 4 towards the pouring means 41. The metering is volumetric, the amount of product being a function the stroke of the scraper piston 5 in the tank 4.

The displacement of the scraper piston 5 is carried out by means of a jack system, not shown, and controlled by commands digital axis, which allow positioning, fast, unlimited and repetitive with very high precision of the scraper piston 5.

It can also be seen in these figures that the scraper piston 5 has an opening 50 as well as a valve 51 capable of opening or closing this opening 50.

In this embodiment, the opening 50 and the valve 51 are coaxial with the scraper piston 5, the valve 51 being carried by a rod 52 axially passing through the rod 53 carrying the scraper piston 5, the displacement of the rod 52 being ensured by a cylinder, not shown.

With more specific reference to FIG. 1, it can be seen that in a first step, the tank 4 and the chamber 42 are completely filled with product P, the chamber 42 being of course equipped with means, not shown, capable of allowing let out the trapped air.

As can be seen in FIG. 2, by the descent, according to a precise predetermined stroke of the scraper piston 5 in the tank 4, a dose of product P is obtained which passes through the pouring means 41 then falls into a container C.

Note that during the descent of the scraper piston 5, the chamber 42 is supplied by the pipe 43, and therefore remains filled with product P.

Referring now to FIG. 3, it can be seen that the opening 50 of the scraper piston 5, which of course is closed by the valve 51 when the scraper piston 5 is lowered, is open when the latter is raised, in so that the product P crosses the scraper piston 5 and fills the tank 4. Advantageously, due to the design of the metering and filling device 2 according to the invention, the tank 4 is constantly empty of air, so that the volumetric metering is of great precision, unlike currently known installations .

The containers C scroll step by step on the fitting means 3 at the rate of the creation of doses of product P, which can, depending on the volume of each of them of course, be carried out successively in a back and forth movement from the scraper piston, or alternatively in a series of several thrust strokes of the scraper piston 5 each delivering a dose, followed by a rise in the filling of the tank 4.

The weighing means 31 makes it possible, at the start of the packaging process, to verify that the quantity of product P delivered by the pouring means into the containers C corresponds to the quantity calculated theoretically, in the case of a difference in the travel of the scraper piston is adjusted.

The weighing means 31 is also used sporadically to meet the standards.

Furthermore, during operation, in particular during a large series, the scraper piston can wear out and therefore be less leaktight, so that the quantity of product delivered is less than it should be. In this case, controlling the quantity of product delivered per dose, by means of the weighing means, can make it possible to adjust the stroke of the scraper piston 5.

Referring now to Figure 4, we can see a particular embodiment of the scraper piston 5, where the opening 50 and the valve 51 are of annular shape. Thus, the valve 51 has a central recess 54 authorizing the circulation of the product P when the valve 51 is closed, so as to avoid the formation of an air pocket under the valve 51 in the case where it has a disc shape.

Furthermore, note the particular profile of the valve 51, that is to say that it has, in section, an upper edge 55 of rounded shape, intended to come into contact with the scraper piston 5, and a lower edge 56 making an angle, so as to improve the circulation of the product P and not to have a horizontal flat surface capable of promoting the creation of an air pocket.

On the other hand, in Figure 5, we can see in a variant that the scraper piston 5 has a concave profile below intended to avoid the formation of an air pocket. Thus, its lower face 57 has, between the opening 50 and the peripheral lip 58 for scraping, an inclined wall 59.

Referring now to FIG. 6, we can see a valve 6 intended to equip the pouring means 41 of the tank 4, not shown, and provided with an anti-drip device 7.

This anti-drip device 7 comprises a frame 70 which can be joined reversibly to the valve 6 by means of a clamping system of known type, comprising a groove 60 in which the anti-drip device 7 engages by an edge while that the opposite edge is blocked by a movable element, not shown, of eccentric type.

The frame 70 is in the form of a frame which maintains a horizontal stack of plates 71, also visible in FIG. 7, these plates 71 each comprising on one face 72 parallel ridges 73 intended, in association with the opposite face 74 of the adjacent plate 71, to create parallel channels 75 arranged in the vertical direction. Advantageously, the ridges 73 have a V-shaped profile, so that the channels 75 have a triangular section, knowing that a polygonal shape increases the retention by capillarity.

The plates 71 can be kept juxtaposed by various means, they can for example include elements allowing transverse sliding in the frame 70.

Advantageously, the cleaning of the anti-drip device 7 is easily carried out, the plates 71 being separated from the frame 70 and washed individually, before being reassembled.

Note that it is possible to assemble the plates 71 face 72 against face 72, so as to put the ridges 73 facing two by two and thus create wider channels 75, in this case of square section.

It will also be noted that it is possible that the two aces of the plates 71 are striated, so as to multiply the number of channels.

Claims

1) Installation for high-throughput packaging of a liquid, viscous or pasty product, loaded or not, of the type comprising a tank (4) equipped below with a valve-type discharge means (6) equipped with a anti-drip device (7) capable of allowing doses of said product (P) obtained under the thrust of a scraper piston (5) capable of moving vertically along a stroke, or a succession of strokes, of given length via control means, said scraper piston (5) comprising a valve or the like capable, in coordination with the movement of said scraper piston (5), of opening and closing to allow the filling of the tank (4) through said scraper piston (5), characterized in that said valve comprises an opening (50) made in said scraper piston (5) and a valve (51) capable of closing said opening (50) from below while being operated by the via a cylinder whose rod (52) passes axially through said scraper piston (5).

2) Installation according to claim 1, characterized in that the valve (51) is of annular shape.

3) Installation according to claim 2, characterized in that the valve (51) has a profile capable of promoting the circulation of the product (P) in one direction or the other depending on the opening or closing movement of said valve (51).

4) Installation according to claim 3, characterized in that the valve (51) has a section having on the side of the scraper piston (5) a rounded profile (55), and on the other side an angled profile (56).

5) Device according to any one of the preceding claims, characterized in that the scraper piston (5) has a concave lower face (57).

6) Device according to claim 5, characterized in that the lower face (57) of the scraper piston (5) has an inclined wall (59) extending between the opening (50) and the peripheral scraping lip (58) .

7) Installation according to any one of the preceding claims, characterized in that the anti-drip device

(7) is removable, and is made up of the juxtaposition, face to face, of plates (71), held by a clamping means, and each having on at least one of their two faces (72, 74), grooves (73) or the like, parallel, so that said faces (72, 74), grooved or not, cooperate to create parallel channels (75) through which the product (P) to be dosed can pass.

8) Installation according to claim 5, characterized in that the grooves (73) have a V-shaped cross section.

9) Installation according to any one of the preceding claims, characterized in that the means for controlling the length of the stroke of the scraper piston (5) are associated with a means (31) for weighing the containers (C) during filling of these, in order to allow a comparison and possible adjustment of the characteristics of said race.

10) Installation according to claim 7, characterized in that the weighing means is integrated into a layout path on which the containers move step by step, at the rate of production of doses of product.