DE29820270U1 - Degassing and gassing valve - Google Patents

Description

Utility model application

Applicant :

Dr. Ing. W. Frohn GmbH, Geiselgasteigstr. 100, 81545 Munich

Release and vent valve Description of the invention

The invention relates to a degassing and gassing valve in the closure for containers, in particular for dangerous liquids in whose valve sleeve, which is open towards the interior of the container, a closed-pore foam plug is pressed in with pre-tension.

When filling transport containers such as bottles, canisters, barrels or larger containers with gaseous liquids, in particular inorganic and organic peroxides, these must be equipped with a pressure relief device in the form of a degassing valve, preferably located in the closure of the container, in order to prevent the containers from swelling and bursting.

Such degassing valves in container closures such as screw caps or bung plugs are known per se.

However, many of these systems are not able to simultaneously meet the following two main conditions for safe transport and storage.

Especially with thin-walled plastic containers, the degassing effect must begin at very low pressures of less than 0.1 bar in order to avoid excessive expansion of the containers. With the known degassing valve systems using a silicone mushroom or ball valve, the degassing effect only begins above 0.1 bar due to the design.

Another criterion is the absolute liquid-tightness of the degassing valve system, even with filled and upside-down containers, over a period of at least 5 minutes, which is not yet guaranteed by many degassing systems.

The object of the invention is to achieve complete liquid-tightness of such a degassing valve, even when a filled container is upside down and in the event of surge loads, while maintaining the permeability for gas separated from the transport liquid even at a very low overpressure compared to the atmosphere of 0.02 to 0.04 bar.

³ 12· Ii-96

The solution to the problem arises from the requirements.

An embodiment of the invention is explained in more detail below with reference to the drawings.

These show in

Figure 1 shows an axial section through an inventive

Degassing valve with foam plug pressed into the inside of the valve sleeve

Figure 2 shows an axial section through an inventive

Degassing valve with foam plug pressed into the valve sleeve and splash protection cap with slot underneath

Figure 3 is a plan view of the underside of the same valve as in Figure 2.

Figure 4 shows an axial section through an inventive

appropriate degassing valve with foam plug pressed into the valve sleeve and underneath it pressed into the valve sleeve,

slotted push-in cap supporting the foam plug.

In embodiment 1 (Figure 1), the closure top (1) of the closure has an opening (2) as a gas outlet opening* which leads into the interior of a valve sleeve (3) that is open at the bottom. A cylindrical, closed-pore foam plug (4) is pressed into this valve sleeve with pre-tension.

A circumferential bead on the inside of the valve sleeve (5) also prevents this foam plug from falling out.

Even at very low overpressure in the container from 0.02 to 0.04 bar, the gas generated passes between the inner wall of the valve sleeve (3) and the cut cells on the edge of the foam body (4) on the inside of the valve sleeve. Depending on the size of the pores or cells or the length of the foam plug (4) or its diameter and compression, the gas passage can be reproducibly adjusted over a very wide range.

If the filled transport container is placed at an angle or upside down, the labyrinth

·

The effect between cut cells or pores and the inside of the valve sleeve effectively slows down the passage of liquid (permeation). The effectiveness of the labyrinth depends on the pre-tension and quality of the foam plug.

The aforementioned valve has the advantage over most commercially available systems that not only does gas escape from the container to the outside, but air can also enter the interior of the container through the valve. This fact means that even when the filled container is transported under very different pressure conditions, e.g. over high mountains, in an airplane or when solvents permeate through the container wall, a negative pressure can never develop in the container, which could cause dents in the container walls and thus a reduction in the stacking compressive strength of the container.

The embodiment 2 (Figures 2 and 3) is almost identical to the embodiment 1 in terms of its functionality. Here, a cup-shaped seal is only used on the outside of the valve sleeve (3) for reasons of additional security to prevent the escape of liquid drops after extreme liquid impacts, which occur, for example, when a container falls onto the closure.

shaped cap (6), preferably made of PE, which has a slot (11) on its base. This cap (6) preferably has circumferential sealing lips (9) on its inner wall above the inner bead (7), which seal against the outer wall of the valve sleeve (3). The purpose of this cap (6) is, on the one hand, to reduce the kinetic energy of the filling material in the event of extreme liquid impacts, which would act directly on the foam plug (4) without the cap. On the other hand, it has the task of giving the foam plug (4) an even pre-tension and thus supporting the so-called memory effect. The foam plug (4) therefore remains dimensionally stable and functional over a long period of time.

The way in which the embodiment 3 (Fig. 4 ) works is almost identical to the embodiment 2. Here, a press-in cap (12) with a slot (13) and curved at the bottom towards the foam plug (4) is pressed into the valve sleeve (3) behind the foam plug with pre-tension until its collar (14) rests against the lower edge of the valve sleeve (3). The curved bottom of this press-in cap (12) rests against the foam plug (4) with pre-tension in order to ensure its dimensional stability over a long period of time.

List of reference symbols

1. Closure top

2. Opening in the top of the closure

3. Valve sleeve

4. closed-cell foam plug

5. circumferential bead

6. Cap

7. Inner bead in the cap

8. circumferential recess

9. Sealing lips

10. Cap base

11. Slot in the cap base

12. Press-in caps

13. Slot in the bottom of the push-in cap

14. Collar of the press-in cap

Claims (5)

-7- ··:. 1 j .OX Protection claims: 1. Venting and gassing valve in the closure of the filling and emptying opening of a container for particularly dangerous liquids, the closure top (1) of which has an opening (2) and in front of this on the inside of the closure top (1) a valve sleeve (3), characterized in that a closed-pore foam plug (4) made of plastic, preferably radiation-crosslinked, semi-rigid particle foam made of polyethylene or ethylene copolymer, is pressed into the valve sleeve (3) with pre-stress, so that a labyrinth is formed by the cut cells of the foam plug resting on the inside of the valve sleeve (3). 2. Degassing valve according to claim (1) characterized in that the foam plug (4) is secured against slipping out by a circumferential bead (5) on the inside of the valve sleeve (3). 3. Degassing valve according to claim (1) and (2) characterized in that the valve sleeve (3) a cup-shaped cap (6) with slot (11) is pressed into the base (10), which seals against the passage of liquid by means of sealing lips (9) on the outside of the valve sleeve (3). 4. Degassing valve according to claim (1), (2) and (3) characterized in that the base (10) of the cup-shaped cap (6) lies flat against the top of the foam plug (4) and secures it against deformation. 5. Degassing valve according to claim (1) and (2), characterized in that a press-in cap (12) with a base curved towards the foam plug (4) is pressed into the valve sleeve (3) behind the foam plug (4) and is pre-tensioned on the top of the foam plug (4) and secures it against deformation.