摘要 |
A cap and valve assembly for a liquid reservoir has a cover in which is disposed a flexible valve member. The flexible valve member has an annular sealing portion engaging the reservoir and a diaphragm portion. An air chamber is formed between the diaphragm portion and the cover, which chamber expands and contracts in response to mechanical vibrations of the reservoir, whereby air is drawn from atmosphere and pumped to the interior of the reservoir. The valve member is spring-loaded when the cap assembly is secured to the reservoir in a manner to assist the annular sealing contact and to establish the at rest volume of the air chamber.
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