Patent ID: 6092695
Filing Date: 2000-07-25
Classification: B01L,B05B,B67D,F04B,F16K,G01N

Abstract:
A liquid dispensing assembly comprising:a liquid reservoir;a liquid metering chamber comprising a compressible elastomeric housing to receive liquid through an inlet from the reservoir; andunidirectional check valves positioned at the inlet and an outlet, respectively, of the compressible elastomeric housing, at least one of the check valves comprising:a flexible membrane having an aperture the flexible membrane being formed as a unitary part with the compressible elastomeric housing; anda valve seat that seats into the aperture of the flexible membrane and causes the flexible membrane to be deformed;the deformed flexible membrane having an elastic restoring force, the restoring force causing the flexible membrane to act upon the valve seat to provide a positive liquid seal.