Metered quantity dispensing valve

Claim 1

A valve assembly for dispensing a metered quantity of a flowable product from a container having a pressurized interior ambient, said valve assembly when installed in said container comprising: A. a valve body having a discharge portion extending out of said container, and a main body portion residing within said pressurized ambient; B. said valve body defining a primary flow passage extending through from said discharge portion to said main body portion, enabling said flowable product to be expelled from said container; C. spring biased discharge valve means positioned within said discharge portion to release said flowable product from said container; D. product metering container means positioned within said pressurized interior ambient, in fluid registry with said main body portion, having a metering chamber adapted to hold a predetermined quantity of said flowable product, said metering chamber defined by a member having a rigid concave inner wall and a resilient wall positioned over said concave inner wall in fluid-tight engagement with said member about the entire outer boundary of said concave inner wall, said resilient wall exposed to said pressurized ambient and adapted to collapse against said concave inner wall in response to fluid pressure to expel flowable material from said chamber; E. a secondary flow passage connecting said metering chamber and said primary flow passage; F. a tertiary flow passage providing a fluid inlet to said chamber from said pressurized interior ambient; and G. a second flow-switching valve means positioned in communication with said product metering container means, actuated in response to the operation of said discharge valve means, to prevent ingress of said flowable product from said pressurized interior ambient into said chamber when said discharge valve means is positioned to enable the expulsion of said flowable product out of said chamber and said container to occur.