Following plate

Abstract

The invention relates to a follower plate (10) for closing a container for viscous material, said container having an upwardly open container bottom and a container wall extending upwardly from the container bottom, the following plate can be moved against an inner surface of the container wall facing the interior of the container in the direction of the bottom of the container and has a plate body (12), in which a material outlet opening for conveying the viscous material from the container and at least one air outlet opening (20) for discharging air from the container are provided. According to the invention, a valve seat (26) of an exhaust valve (24) is arranged in each exhaust opening (20), said valve seat being rigidly connected to the plate body (12).

Description

Technical Field

[0001] The invention relates to a follower plate for closing an upwardly open container according to the preamble of claim 1 . Background Art

[0002] A follower plate of the type mentioned at the outset is known, for example, from DE 10 2020 127 440 A1. The follower plate is a component of a device for conveying viscous material from a barrel-shaped, upwardly open container. In order to convey the material, the follower plate is introduced into the container from above and moves in a sealed manner on the inner surface of the container wall toward the bottom of the container, following the material level that decreases when the container is emptied, while resting on the surface of the material in the container until the container is empty. If the container is emptied, the follower plate is removed from the container and introduced into another full container. The follower plate has a plate body, the lower side of which rests on the material in the container, and a material outlet is arranged in the plate body, through which the material is conveyed from the barrel by means of a conveying pump. In order to allow the air contained between the surface of the material and the lower side of the plate body to escape before the start of the conveying process, at least one exhaust opening is arranged in the plate body. If there is no longer air in the container, the exhaust opening must be sealed so that no viscous material can escape from the exhaust opening or air can enter the container again. For this purpose, each exhaust opening is provided with an exhaust valve, which can close and release the exhaust opening. A vacuum pump is usually also connected to the exhaust opening.

[0003] Since viscous material can penetrate into the exhaust opening in small quantities during exhaust, it is necessary to clean the exhaust valve regularly in order to remove contamination caused by the viscous material. This is complex. Summary of the invention

[0004] It is therefore an object of the present invention to further develop a follower plate of the type mentioned in the introduction in such a way that simpler cleaning is possible.

[0005] This object is achieved according to the invention by a follower plate having the features of claim 1. Advantageous further developments of the invention are the subject matter of the dependent claims.

[0006] The idea of ​​the present invention is to integrate the valve seat into each exhaust opening and to connect it fixedly to the plate body. The valve seat is therefore not part of a valve unit that is detachably mounted on the plate body, but an integrated component of the plate body. It is preferred that each of the valve seats is pressed into the plate body in a force-locking manner, so that the valve seat is held in the plate body by a friction lock. It is suitable that each of the valve seats is made of plastic, so that the valve seat is soft on the one hand and can be advantageously manufactured on the other hand. The contaminated valve seat can then be simply removed from the plate body by means of a cutting method, in particular by means of a drilling tool. It is further preferred that each of the valve seats has a conical abutment surface for a valve needle. This enables good sealing, in particular by means of a valve needle made of a hard material.

[0007] For the sealing closure of the at least one exhaust opening, it is expediently provided that a valve unit is assigned to each exhaust opening, the valve unit having a valve needle for closing the exhaust opening on its valve seat and an actuating device for moving the valve needle between a closed position, in which the valve needle is placed sealingly on a valve seat received in the exhaust opening, and an open position, in which the valve needle is lifted from the valve seat. Expediently, each valve unit has a valve housing, through which the exhaust channel leading into the associated exhaust opening extends, and from which the valve needle protrudes at least in the closed position. It is particularly preferred that the distance by which the valve needle protrudes from the valve housing in the closed position is at least one third, preferably at least half, of the thickness of the plate body between its underside and the upper side, on which the valve housing is placed. The valve housing is then arranged at a distance relative to the valve seat, so that the valve housing is less contaminated by viscous materials. The valve needle is expediently made of hard metal, which has a high hardness, is chemically durable and can be easily cleaned. Here, hard metal is understood to be a metal matrix composite material in which the hard material in the form of particles is held together by a matrix made of metal. As hard materials, metal carbides or metal nitrides, such as tungsten carbide, titanium carbide, titanium nitride, niobium carbide, tantalum carbide or vanadium carbide, are used in particular. In particular, each valve unit is detachably fixed to the plate body, so that the valve unit can be removed from the plate body as a whole and without damaging it. Through this measure, the expensive components of the relevant valve combined in the valve unit, namely the valve needle, valve housing and operating device, can be detached and cleaned from the plate body as an integral unit without great expenditure. The valve seat, which is constituted as a cheap wearing part, on the contrary remains in the plate body and is removed from the exhaust opening that receives it, wherein the valve seat is preferably destroyed. When servicing the follow-up plate, it is expedient to proceed in this way, that is, each valve unit is removed from the plate body and cleaned if necessary, then, if necessary, each of the valve seats is removed from the exhaust opening that accommodates it and replaced by a new valve seat, and finally each of the valve units is releasably fastened to the plate body again. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The invention will now be further explained with reference to the exemplary embodiments schematically shown in the accompanying drawings.

[0009] Figure 1 A perspective view showing a follower plate with a connected container pump;

[0010] Figure 2 Shown in accordance with Figure 1 A partial view of a cross section of a follower plate;

[0011] Figure 3 A perspective view showing a valve unit and

[0012] Figure 4 Shown in accordance with Figure 3 Cross-sectional view of the valve unit. DETAILED DESCRIPTION

[0013] The follower plate 10 shown in the drawings is used to convey viscous materials such as adhesives, sealing materials, sound insulation materials or heat-conducting pastes from an upwardly open barrel-shaped container (not shown in the drawings). The follower plate 10 is introduced into the container through the upper open side of the container. The follower plate has a plate body 12 and is pressed with the lower side 14 of the plate body 12 onto the surface of the material contained in the container. The follower plate 10 also has two sealing and scraping rings 16 surrounding the circumference of the plate body 12, which are in sealing contact with the inner surface of the container wall facing the container interior in order to prevent the material from escaping from the container between the container wall and the follower plate 10. During the conveying process, the follower plate 10 moves in the direction of the container bottom, following the decreasing material level in the container, until the container is emptied. The material is conveyed through a material outlet in the plate body 12, not further shown, by means of a container pump 18.

[0014] A plurality of exhaust openings 20 are provided in the plate body 12, which extend between the bottom side 14 of the plate body 12 and an upper side 22 facing away from the bottom side 14. At each exhaust opening 20, the follower plate 10 has an exhaust valve 24, which is designed as a needle valve. Each of the exhaust valves 24 has a valve seat 26 made of plastic, which is pressed into the plate body 12 in a force-locking manner, and a valve unit 28 which is detachably connected to the plate body 12 by means of a screw connection. Each of the valve units 28 has a valve housing 30 and a valve needle 32 which is linearly movable in the valve housing 30, which protrudes from the valve housing 30 and in the closed position rests in a sealing manner on a conical contact surface 34 of the associated valve seat 26. In addition, each valve unit 28 has an actuating device 36, which acts on the valve needle 32 in order to move the valve needle from the closed position into the open position, in which the valve needle is lifted from the valve seat 26. Furthermore, an exhaust duct 38 extends through the valve housing 30 , which exhaust duct communicates with the corresponding exhaust opening 20 and to which a vacuum pump can be connected.

[0015] When the follower plate 10 is introduced into a container filled with a viscous material, the exhaust valve 24 is opened by placing its valve needle 32 in the open position. The air contained in the container can then escape from the exhaust opening 20, or the air is actively pumped out by means of a vacuum pump. When there is no longer air in the container between the material surface and the follower plate 10, the exhaust valve 24 is closed and the material is conveyed from the container by means of a container pump 18. During exhaust, the viscous material regularly contacts the components of the exhaust valve 24. These components can therefore become clogged and worn over time by contamination with the viscous material. Therefore, during the maintenance of the follower plate 10, the valve unit 28 is detached from the plate body 12 and removed. The valve needle 32, which protrudes from the valve housing 30 both in the closed position and in the open position, is now easily accessible and can be cleaned by removing the adhesion of the viscous material therefrom. The valve seat 26 can also be cleaned, which, unlike the valve unit 28, cannot be detached from the plate body 12 without destruction or without damaging it. However, the valve seat is usually removed from the plate body 12 , for example by drilling out, and is replaced by a new valve seat 26 .

[0016] To summarize:

[0017] The present invention relates to a follower plate 10 for closing a container for viscous material having an upwardly open container bottom and a container wall extending upwardly from the container bottom, the follower plate being movable toward the container bottom while being in contact with the inner surface of the container wall facing the container interior and having a plate body 12, in which a material outlet for conveying the viscous material from the container and at least one exhaust opening 20 for draining air from the container are arranged. According to the present invention, a valve seat 26 of an exhaust valve 24 fixedly connected to the plate body 12 is arranged in each exhaust opening 20.

Claims

1. A follower plate for closing a container for a viscous material, the container having an upwardly open container bottom and a container wall extending upwardly from the container bottom, the follower plate being able to move toward the container bottom while being in contact with an inner surface of the container wall facing the interior of the container, and the follower plate having a plate body (12), in which a material outlet for conveying the viscous material from the container and at least one exhaust opening (20) for discharging air from the container are arranged, characterized in that: A valve seat (26) of an exhaust valve (24) which is fixedly connected to the plate body (12) is arranged in each exhaust opening (20).

2. The follower plate according to claim 1, characterized in that: Each of the valve seats (26) is an integral component of the plate body (12).

3. The follower plate according to claim 1 or 2, characterized in that: Each of the valve seats (26) is pressed into the plate body (12) in a non-positive manner.

4. Follower plate according to any one of the preceding claims, characterized in that Each of the valve seats (26) is made of plastic.

5. Follower plate according to any one of the preceding claims, characterized in that Each of the valve seats (26) has a conical contact surface (34) for a valve needle (32).

6. Follower plate according to any one of the preceding claims, characterized in that A valve unit (28) is assigned to each exhaust opening (20), the valve unit having a valve needle (32) for closing the exhaust opening (20) on its valve seat (26) and an actuating device (36), the actuating device being used to move the valve needle (32) between a closed position and an open position, in which the valve needle is sealingly placed on a valve seat (26) received in the exhaust opening (20), and in which the valve needle is lifted from the valve seat (26).

7. The follower plate according to claim 6, characterized in that: Each valve unit (28) has a valve housing (30), through which a ventilation channel (38) opens into the associated ventilation opening (20) and from which the valve needle (32) projects at least in the closed position.

8. The follower plate according to claim 7, characterized in that: The distance by which the valve needle (32) protrudes from the valve housing (30) in the closed position is at least one third, preferably at least half, of the thickness of the plate (12) between its underside (14) and an upper side (22) on which the valve housing (30) rests.

9. The follower plate according to any one of claims 6 to 8, characterized in that Each valve needle (32) is made of hard metal.

10. The follower plate according to any one of claims 6 to 9, characterized in that Each valve unit (32) is detachably fastened to the plate body (12).

11. Method for repairing a follower plate according to claim 10, characterized in that At least one valve unit (28) is removed from the plate body (12), at least one valve seat (26) is removed from an exhaust opening (20) receiving the valve seat and replaced by a new valve seat (26), and the at least one valve unit (28) is releasably fastened to the plate body (12) again.

12. The method according to claim 11, characterized in that The at least one valve seat (26) is destroyed when removed from the exhaust opening (20) receiving the valve seat.

13. The method according to claim 12, characterized in that The at least one valve seat (26) is removed from the exhaust opening (20) receiving the valve seat by means of a cutting method.

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