VENTING COVER

Abstract: A cover for a filling or dispenser spout (5) for a storage holder such as a liquid container, which cover consists of a circular body (1) having arranged along the periphery thereof a flange member (2) provided with fastening means (3) such as a screw-thread, co-operating with the spout (5) and a sealing ring (7) fitted inside the flange member, wherein the circular part of the cover located inside the sealing ring is provided with a discharge opening (8) which can be closed off from the container content by a pressure sensitive closing means (9) arranged inside the cover, said closing means being a dome-like structure (13) co-operating with a diaphragm (10) with a passage opening (12), such that the content of a storage holder can be vented without the content thereof, for instance an aggressive liquid, being able to escape to the outside.

Description: The invention relates to a venting cover assembly comprising a cover having a top provided with a first vent opening, a peripheral flange having an inner side provided with means for securing the cover in sealing association with a spout of a container, an inner flange, insert means having an annular groove receiving said inner flange and frictionnally fitted thereon and pressure-sensitive diaphragm means between said cover and said insert means for forming an ambient pressure chamber between the cover and the diaphragm means which communicates with ambient atmosphere through said first opening, wherein the diaphragm means is provided with at least one second vent opening seated on an upwardly protruding portion of said insert means. Such a cover is disclosed in US-A-4,122,943. The invention has for its object to improve a cover of the type described in the preamble such that the content of a comparatively upright positioned storage holder can be vented without the content thereof, for instance an aggressive liquid, being able to escape to the outside. The cover according to the invention is distinguished in that said insert means is dish-shaped so that a secondary chamber is formed between the diaphragm means and the insert means, said insert means including a third vent opening communicating the interior of the container with the secondary chamber wherein the diaphragm means at the second vent openings is tensioned by said upwardly protruding portion to form at least one check valve capable of venting the interior of the container only by the movement of the diaphragm in the direction of the ambient pressure chamber. In this way, when there is momentary overpressure in the container, this overpressure can be reduced by allowing gas to escape. In the case the container suddenly falls or is knocked over the discharge opening will be closed off by the closing means so that no liquid can flow outside via the discharge opening. A particularly effective action is obtained if the support has a dome-like structure on which the diaphragm rest with its passage opening. The response time for opening of this passage following an increase in pressure in the container is hereby shortened considerably. The invention is further elucidated hereinafter with reference to the annexed drawing of an embodiment. In the drawing: Fig. 1 and 2 each show a similar upright view of the cover according to the invention in respectively the closed and opened positions of the closing means. The cover shown in the figures consists of a circular body 1 which is provided along the periphery with a cover flange member 2. This flange member is formed with an internal thread 3 which co-operates with a thread 4 on the outer periphery of a filling or dispenser spout 5 of a container 6 that is not further shown or described. Accommodated between the circular body 1 and the upper edge of spout 5 is a sealing ring 7 which, when the cover is screwed onto spout 5, is clamped in position so that a closed connection is effected between cover 1 and spout 5. In accordance with the invention the circular body 1 of the cover is formed with a discharge opening 8. This discharge opening may have any random form and more than one thereof can moreover be arranged. This discharge opening 8 can be screened off from the container contents and from the space inside spout 5 by closing means which are generally designated with 9. The closing means consist substantially of a diaphragm 10 of thin sheet-like material which is flexible such that movement in axial sense is possible. Diaphragm 10 is formed with a downward hanging edge portion 11 which is fixed in position in a manner to be further explained below. Diaphragm 10 is formed with a passage opening 12. This passage opening lies on the top of a dome-like support 13, which support forms a part of a dish-like insert piece 14. The portion of the dish 14 located adjoining the dome-like support 13 is formed with a passage opening 15, only one of which is drawn, although it will be apparent that more than one can be arranged. The same applies to the passage openings 12, whereby more dome-like supports 13 can then be formed on dish 14. The dish-like insert piece 14 is formed with an annular groove 16 in which is accommodated a downward hanging flange 17, which is likewise annular and is moulded on the underside of the circular part 1 of the cover. The dish-like part 14 is formed in addition with an edge portion 18 extending along flange 17 which then continues along the outer periphery as a radially protruding flange 19. Arranged between flange 17 and edge portion 18 is a snap coupling in the form of a tongue/groove connection 20. The downward hanging edge portion of diaphragm 10 is likewise provided with a tongue 21 which co-operates with a groove 22 in the internal wall part of the groove 16. Assembly of the parts of the above described venting cover takes place as follows. The diaphragm 10 is placed on insert piece 14 such that the edge strip 11 enters groove 16 and is pressed on until tongue 21 falls into groove 22. The dome-like support 13 is hereby directed toward diaphragm 10. The insert piece is then snapped into position in the cover, whereby the snap coupling 20 ensures a permanent attachment. Finally, the sealing ring 7 is fitted and the cover is ready for use. When the insert piece 14 is fitted the dome-like support 13 will bias diaphragm 10 in the direction of the circular body 1 of the cover and therefore place it under tension. Passage opening 12 is sealed off by support 13. A completely closed off spout 5 will therefore result when the cover is screwed onto spout 5, on the one side as a result of sealing ring 7 and on the other as a result of diaphragm 10, the edge strip 11 of which lies clamped in position between flange 17 and the inner wall of groove 16. When overpressure occurs however the pressure will act via the passage opening 15 on the underside of diaphragm 10, which diaphragm 10 will be lifted at a determined overpressure from dome-like support 13, which will result in the release of passage opening 12, see fig. 2. The gas under pressure will immediately flow away via this passage opening 12 and discharge opening 8 to the outside. As soon as a balance has been established diaphragm 10 returns to the starting position as in fig. 1 and the opening 12 is closed off. It will be apparent that there is no possibility in the case of underpressure that gases can enter into the storage holder from outside, because the diaphragm 10 is pressed permanently in position on dome-like support 13 and does not therefore release the passage opening 12. The invention is not limited to the above described embodiment.

Claims: 1. A venting cover assembly comprising a cover having a top provided with a first vent opening (8), a peripheral flange (2) having an inner side provided with means (3, 4) for securing the cover in sealing association with a spout (5) of a container, an inner flange (17), insert means (14) having an annular groove (16) receiving said inner flange (17) and frictionally fitted thereon and pressure-sensitive diaphragm means (10) between said cover and said insert means for forming an ambient pressure chamber between the cover (1) and the diaphragm means (10) which communicates with ambient atmosphere through said first opening (8), wherein the diaphragm means (10) is provided with at least one second vent opening (12) seated on an upwardly protruding portion (13) of said insert means (14) characterised in that said insert means (14) is dish-shaped so that a secondary chamber is formed between the diaphragm means (10) and the insert means (14), said insert means (14) including a third vent opening (15) communicating the interior of the container with the secondary chamber wherein the diaphragm means (10) at the second vent openings (12) is tensioned by said upwardly protruding portion (13) to form at least one check valve capable of venting the interior of the container only by the movement of the diaphragm in the direction of the ambient pressure chamber. 2. A venting cover assembly as defined in claim 1, wherein the localized portion includes a dome-like portion (13) to tension the diaphragm means (10) and to close off said second vent opening (12).

Inventors: JONKERS, GODEFRIDUS HUBERTUS J.
Applicants: WIVA VERPAKKINGEN B.V.
Application year: 1988
Main classification: B65D51
IPC codes: B65D51