EP0495374B1 - Venting device for containers - Google Patents

Abstract

The venting device consists of a pipe nozzle (14) which is welded to the container wall (11) of a container (10) and onto which a screw cap (50) is screwed. Combined with this screw cap (50) is an excess pressure valve which is formed by a cylindrical portion (52) of the cap (50) with radial bores (54a, b) which are closed under normal pressure by a tensioned annular element (55) made of rubber-elastic material. To protect the inside region of the pressure compensating device from splashing in the region of the annular element (55), the pipe nozzle (14) is covered by a flat ring (16a) as a safeguard against gushing. <IMAGE>

Description

The invention relates to a ventilation device for containers of the type specified in the preamble of claim 1.

Containers, e.g. Small containers that are used for the storage and transport of liquids are usually provided with a ventilation device through which air can flow in during filling or emptying. In the simplest case, such a ventilation device consists of a pipe socket, which is attached to the container wall or the container top and can be closed with a screw cap.

According to recent regulations, containers for holding liquids must be equipped with an additional pressure compensation device, which essentially consists of there is a pressure relief valve that opens automatically when the internal pressure of the container is increased. This measure is intended to prevent damage, in particular bursting, of the container when the contents of the container are heated, for example as a result of heating, so that excessive pressure is built up in the container. Such heating can occur both in the event of a fire and as a result of excessive sunlight. The pressure relief valve should close again automatically when the permissible nominal pressure is reached.

The pressure relief valves provided in containers in addition to the ventilation device usually have a piston or plate closing the valve bore, which is raised by the gas or vapor pressure present against the action of a return spring, thereby releasing the valve opening. Pressure relief valves of this type, the pistons or tappets of which must rest on a precisely machined valve seat, are relatively complex and, compared to the often scarcely calculated costs of simple containers, are too expensive.

From GB-A-995 696, from which the invention is based, it is known to implement the valve function through a bore closed with a rubber-elastic element. For this purpose, a pipe socket is attached to the container in the area of the container top, which is sealed gas-tight with a screwed-on cap. The cap has a continuous radial bore, which is closed by a rubber-elastic ring element, which is placed under prestress in its area. When a predetermined internal container pressure is exceeded, the rubber-elastic ring element is lifted off the radial bore. After pressure equalization with the outside atmosphere, the ring element returns due to its rubber-elastic behavior back to its starting position and closes the radial bore.

A comparable ventilation device is also known from GB-A-1 136 403, where the radial bore is not realized on the outer circumference of the cap, but within an integrally formed recess, so that the rubber-elastic band which closes the bore is within the Well arranged and thus protected from damage.

Although these known ventilation devices are mechanically simple and therefore inexpensive to implement, they have problems in practical use. There is a risk that, during the transport or transfer of such containers, the liquid therein carries out strong movements, with the result that a considerable amount of liquid gets into the area of the radial bores and wets the annular sealing element from the inside. In extreme cases, this can also result in the ring element being lifted off briefly as a result of gushing liquid and liquid escaping in an uncontrolled manner.

The present invention has for its object to improve a ventilation device of the type mentioned in such a way that it no longer has the disadvantages described and in particular the liquid movements occurring during transport and implementation do not result in liquid in any significant amount can reach the area of the radial bores and the ring element is occupied from the inside or is lifted off the radial bore.

This object is achieved in a ventilation device of the type specified in the preamble of claim 1 with the features specified in the characterizing part of this claim.

According to this, a surge protection device is realized in that a flat ring with a passage opening is arranged between the cap and the pipe socket, which can be closed by means of a plate which can be lifted off from the passage opening by the action of pressure. This measure has the advantage that when assembling the container the flat ring according to the invention can be used instead of the usual sealing ring without additional assembly effort. The plate is preferably elastically connected in one piece to the flat ring, so that it can be produced particularly easily and without punching waste.

According to a first embodiment according to claim 2, this ring element is designed as a hose membrane, similar to a valve for bicycle tubes, which is clamped onto a cylindrical extension of the cap which has the radial bore.

According to a second embodiment according to claim 3, an O-ring is provided instead of the hose membrane, which is inserted into an annular groove of the cylindrical extension of the cap under tension. Advantageously, several, e.g. Four radial bores are provided, so that even if a bore is dirty, sufficient safety is still guaranteed.

With this simple measure, a deficiency in the safety valves that have been customary up to now is easily remedied. When transporting the container, it is inevitable that the The contents of the container spill up and the safety valve is wetted. Depending on the viscosity of the contents, for example in the case of paint colors, this can lead to the valve piston or disc sticking together, so that the valve does not open at all or opens too late and then leaks. In addition, such valves are extremely difficult to clean.

The valve proposed by the invention does not have these disadvantages. Even if a radial bore is closed, the relief of excess pressure is guaranteed by one of the other bores. If the valve becomes dirty due to deposits between the ring element and the outlet opening of the radial bore and becomes leaky as a result, simple cleaning is possible after removing the ring element. This ring element, consisting of a hose membrane or an O-ring, is extremely inexpensive and can be replaced during cleaning. The material quality of the ring element depends on the compatibility with the contents of the container. With the large number of materials available, sealing rings can be provided even with very aggressive container contents. If desired, combustible material can be selected for the ring element, which creates additional fire protection. Rubber suitable mixture fulfills this condition.

The surge protection device has a pressure-elastic element that opens under excess pressure in the interior of the container and enables pressure equalization. In the closed state, this surge protection device, in particular, blocks the liquid container contents from the valve.

To protect the pressure compensation device, this is according to claim 8 with a protective cap, for example made of plastic, covered. This protective cap protects in particular the hose membrane or the O-ring against mechanical damage from the outside.

Figur 1

teilweise geschnittene Seitenansicht einer Be- und Entlüftungsvorrichtung nach einem ersten Ausführungsbeispiel gemäß der Erfindung,

Figur 1a

Aufsicht auf die in Figur 1 dargestellte Schwallschutzscheibe,

Figur 2

Aufsicht auf die Vorrichtung gemäß Figur 1,

Figur 3

teilweise geschnittene Seitenansicht einer Be- und Entlüftungsvorrichtung nach einem zweiten Ausführungsbeispiel gemäß der Erfindung,

Figur 3a

Aufsicht auf die in Figur 2 dargestellte Schwallschutzscheibe und

Figur 4

Aufsicht auf die Vorrichtung gemäß Figur 3.

The subject matter of the invention is explained below on the basis of preferred exemplary embodiments which are illustrated in the drawings. In these show:

Figure 1

partially sectioned side view of a ventilation device according to a first embodiment according to the invention,

Figure 1a

Top view of the surge protection pane shown in FIG. 1,

Figure 2

Supervision of the device according to FIG. 1,

Figure 3

partially sectioned side view of a ventilation device according to a second embodiment according to the invention,

Figure 3a

Top view of the splash guard and shown in Figure 2

Figure 4

Top view of the device according to FIG. 3.

The left half in Figures 1 and 3 shows the ventilation device in side view, the right half in axial section. The radial bores 54a-d and 74a-d are shown in dashed lines in the top views according to FIGS. 2 and 4. Identical parts are in the drawings with the same numerals, corresponding elements of the cap in the Figures 2 and 4 denoted by the corresponding digits of the fifties and seventies series.

In all exemplary embodiments, a pipe socket 14 is provided as a ventilation device, which is connected to the container top 11 of a container 10. For this purpose, the latter has a collar-shaped outlet connection 12, with which the pipe connection 14 is firmly connected via a weld seam 13. The interior of the container 10 can thus be aerated and vented via the pipe socket 14 directed upward during transport. After filling or emptying, the pipe socket 14 is to be closed, namely in the exemplary embodiment according to FIGS. 1 and 2 with the protective cap 50 and in the exemplary embodiment according to FIGS. 3 and 4 with the protective cap 70, which can be screwed onto the external thread 14a of the pipe socket 14 . The caps 50 and 70, which can be tightened by means of a key to be attached to their hexagon 51 and 71, are captively connected to the container 10 by a ball chain 19. For this purpose, an eyelet plate 15 is welded between the container top 11 and pipe socket 14, in the eyelet 15a of which one end of the ball chain 19 is suspended. The other end of the ball chain 19 has an S-hook, not shown, which wraps around the mushroom-shaped cap shoulder 53 or 73 of the cap 50 or 70.

If necessary, a sealing wire 17 with a seal 18 can be fixed to the same eyelet 15, the other end of which penetrates a transverse bore 57 or 77 of the cap 50 or 70.

What is new is the cylindrical extension 52 or 72, which, as explained below, takes over the function of the pressure relief valve which is used in the previously known containers for transport of liquids was a separate component.

In all of the exemplary embodiments according to FIGS. 1 to 4, the container cap 50 or 70 has an additional cylinder section 52 or 72, the interior 56 or 76 of which is connected to the external atmosphere via radial bores 54a-d or 74a-d. In the exemplary embodiments according to FIGS. 1 and 2, a hose membrane 55 is clamped onto the cylinder section 52 similarly to a bicycle valve under internal stress such that the outlet openings of the radial bores 54a-d are closed up to a certain maximum pressure inside the container. When the predetermined pressure limit is reached, the hose membrane 55 is partially raised in the area of the radial bores 54a-d from the outer surface of the cylinder section 52, so that the gas under pressure can escape. After the nominal pressure has been reached, the bores 54a-d are closed again by the hose membrane 55. In the event of soiling, damage or aging, the hose membrane 55 can be removed and replaced in a very simple manner.

In order to prevent wetting of the hose membrane 55 with the transport goods, in particular with liquid, a surge protection device, consisting of a flat ring 16a, is placed between the cap 50 and the pipe socket 14. This flat ring 16a has a passage opening which can be covered by a tongue 16c elastically connected to it. Under the action of pressure, this tongue 16c deflects out of its rest position and releases the passage opening. To protect the O-ring 75 from wetting, this exemplary embodiment also has a surge protection device, which is arranged between the pipe socket 14 and the screw cap 70 and comprises a flat ring 16a.

Protection against external mechanical stresses on the ventilation device is provided by the protective cap 59 or 79, which has an L-shaped edge cross section. In particular, the hose membrane 55 or the O-ring 75 is protected against mechanical damage and also against contamination by the edge 59a or 79a running parallel to the pipe socket 14.

In the event of a fire, the hose membrane 55 melts or burns, provided that it is made of a suitable material, so that the material under high pressure can escape from the container 10 in gaseous or vaporous or liquid state in the event of excessive heating and the container 10 is prevented from bursting .

In the exemplary embodiment according to FIGS. 3 and 4, an O-ring 75 with a circular cross-section is provided instead of the hose membrane, which is flat in cross-section, which is inserted into an appropriately designed annular groove 78 in the cylinder section 72 of the cap 70 under internal stress. This O-ring also closes the radial bores 74a-d in the same way and with the same advantageous properties as the hose membrane 55 of the exemplary embodiment according to FIGS. 1 and 2. Because of the greater material thickness, higher sealing forces and better sealing effects can be achieved if necessary.

REFERENCE SIGN LIST

10th

container

11

Container top

12th

Connecting piece

13

Weld

14

Pipe socket

14a

External thread

15

Eyelet

15a

eyelet

16a

Flat ring

16b

incision

16c

tongue

17th

Sealing wire

18th

seal

19th

Ball chain

50

Screw cap

51

Hexagon head

52

Cylinder section

53

mushroom-shaped cap approach

54a, b, c, d

Radial bores

55

Hose membrane

56

inner space

57

Cross hole

59

protective cap

59a

edge

70

Screw cap

71

Hexagon head

72

Cylinder section

73

mushroom-shaped cap approach

74a, b, c, d

Radial bores

75

Hose membrane

76

inner space

77

Cross hole

79

protective cap

79a

edge

Claims (9)

1. Ventilating and deventilating device for containers (10), in particular for reception of liquids, comprising a pipe connection (14) mounted on the container wall or on the container ceiling (11) and a cap (50, 70) which is screwed hermetically onto the pipe connection (14) and which has at least one radial bore (54a-d, 74a-d) which connects the container interior with the outside atmosphere and in whose vicinity a rubber-elastic ring element (55, 75) is mounted under pretension in such a way that the radial bore (54a-d, 74a-d) is sealed up to a certain container internal pressure with respect to the outside atmosphere, characterized in that there is disposed between the cap (50, 70) and the pipe connection (40) a flat ring (16a) having a passage opening which can be sealed by means of a plate which is preferably integrally joined elastically to the flat ring (16a) and which can be raised from the passage opening by the action of pressure.
2. Device according to Claim 1, characterized in that the radial bore (54a-d) is provided at a cylindrical section (52) of the cap (50), over which cylindrical section a hose-type membrane (55) which is flat in cross section is stretched.
3. Device according to Claim 1, characterized in that the radial bore (74a-d) is provided at a cylindrical section (72) of the cap (70) which has an annular groove (78) into which an O-ring (75) is inserted under pretension.
4. Device according to Claim 1, 2 or 3, characterized by a plurality of radial bores (54a-d, 74a-d) which pass through the cap (50, 70) and whose outlets are sealed by a common rubber-elastic ring element (55, 75).
5. Device according to one of Claims 1 to 4, characterized in that the plate comprises a tongue (16c) cut into a flat disc.
6. Device according to one of Claims 1 to 5, characterized in that the ring element (55, 75) is composed of combustible material.
7. Device, according to Claim 6, characterized in that the ring element (55, 75) is composed of rubber.
8. Device according to at least one of Claims 1 to 7, characterized by a protective cap (59, 79) which is permanently joined to and covers the screw cap (50, 70) and which has an L-shaped peripheral cross section, wherein the periphery (59a, 79a) which points in the direction of the container ceiling covers the hose-type membrane (55) or the O-ring (75).
9. Device according to Claim 8, characterized in that the protective cap (59, 79) is composed of plastics material.

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