Valve for physiological drainage actuable by lateral compression

Claim 1

A normally-closed valve which can be opened by lateral compression, comprising: a valve body defining an interior flow cavity, an inlet port and an outlet port opening into said flow cavity through said body, a peripheral valve seat having a central axis and lying normally thereto when the body is undeformed and extending continuously around the outlet port and facing into the flow cavity, the valve body and valve seat being flexible and deformable by lateral compressive force exerted externally on the valve body, and a valving member movably disposed in said flow cavity adapted to make a fluid-tight sealing fit with the valve seat when the valve body is undistorted, and to leave a flow passage between them when the valve body is distorted by lateral compression, said valving member comprising a slack flexible diaphragm extending across the flow cavity, said diaphragm including a central imperforate region adapted to Contact the valve seat and close the passage when the valve body is undeformed, said diaphragm having a pair of opposite faces, and a perforation therethrough which lies outside of the said imperforate region and fluidly intercommunicates both of said faces.