RECIPIENT MUNI D'UN JOINT D'AERATION

摘要

1306615 Reciprocating dispensing pumps DIAMOND INTERNATIONAL CORP 29 Dec 1970 [8 Jan 1970] 61517/70 Heading F1A In a hand actuated liquid dispensing pump D mounted on a container 10, a polyethylene or rubber gasket-diaphragm valve 38 is clamped in sealing fashion between the top of the container 10 and a screwed cap 16 and has a downwardly converging tapered frustro-conical flexible lip 38b encircling the pump cylinder 20 in radial sealing engagement therewith below an air vent 36, the seal acting only in one direction to allow air intake for pressure balance with the atmosphere but automatically closing against liquid &c. discharge from the container whereby the container interior pressure is automatically maintained equalized with the atmosphere during long periods of inactivity such as during shipment, and additionally, loss of liquid or blocking of the air vent is avoided when the container is tilted in use. Thus sealing arrangement prevents unsightly distortion or collapse of the container, when formed from a non-rigid material such as plastics for example, normally resulting from unequalized pressures between the container interior and atmosphere. In Fig. 4 (not shown) the seal lip engages the pump cylinder at a point above the air vent 36 whereby the seal simply serves to admit air into the container quite independently of the pump when there is imbalance of pressures.