Patent ID: 6948517

Claim:
A two-way valve comprising: a body in which a fluid passage for flowing a fluid is formed; a piston which is provided in said body displaceably in an axial direction by a pilot pressure; a shaft which is integrally connected to said piston; a first diaphragm which is connected to one end of said shaft and which closes said fluid passage when said first diaphragm is seated on a valve seat formed on said body; and a second diaphragm which is axially attached so that said second diaphragm is coaxially superimposed on said first diaphragm and which is provided displaceably together with said first diaphragm, wherein a space is formed between a first skirt section of said first diaphragm extending radially outwardly and a second skirt section of said second diaphragm extending radially outwardly, and an elastic member is arranged in said space, said elastic member comprising a buffering spring member which is corrugated with a plurality of corrugations extending in a direction from an inner circumferential side to an outer circumferential side of said first diaphragm and said second diaphragm, for urging said first skirt section and said second skirt section to separate from each other, and wherein said plurality of corrugations of said buffering spring member are interposed in said space between said first skirt section and said second skirt section, so that ridge portions of said plurality of corrugations contact a wall surface of said first skirt section and a wall surface of said second skirt section, and said space permeates through plural groove portions of said plurality of corrugations.