Patent ID: 6345803
Filing Date: 2002-02-12
Classification: F16K

Abstract:
A piezoelectric fluid control valve comprising a valve mechanism portion for opening and closing a fluid flow path by displacement of a diaphragm valve and a piezoelectric operating portion for opening and closing said diaphragm valve,wherein said valve mechanism portion includes in a first casing said fluid flow path, a valve seat provided at a midpoint of said fluid flow path, said diaphragm valve for coming in contact with and separating from said valve seat to open and close said flow path and applied with elastic force in such a direction as to separate from said valve seat, and a pressing member in contact with a back face of said diaphragm valve to be displaced with said diaphragm valve in opening and closing directions, said piezoelectric operating portion includes in a second casing connected to said first casing a piezoelectric element laminate for expanding due to application of a voltage, a first member disposed on one end side of said piezoelectric element laminate to transmit expanding force of said piezoelectric element laminate to said pressing member to seat said diaphragm valve on said valve seat, a second member disposed for displacement on the other end side of said piezoelectric element laminate, a spring seat displaced with said second member in expansion of said piezoelectric element laminate, and a valve spring elastically deformed by displacement of said spring seat to repulse said piezoelectric element laminate, and a distortion amount of said piezoelectric element laminate in expansion is set at such a value as to press said pressing member to seat said diaphragm valve on said valve seat and as to press said spring seat in a reverse direction to elastically deform said valve spring.