Patent ID: 6092545
Filing Date: 2000-07-25
Classification: F16K,Y10T

Abstract:
A valve comprising:a housing including a flow control chamber and first, second, and third ports connected to the chamber; anda flow control member mounted in the chamber for movement betweena) a first position where the member blocks flow between the first and second ports, blocks flow between the first and third ports, and allows flow between the second and third ports, andb) a second position where the member allows flow between the first and second ports and blocks flow to the third port from both the first port and the second port; whereinat least a portion of the housing and at least a portion of the flow control member including magnetic material arranged to generate a magnetic force between the housing and the flow control member that is greater with the flow control member in the first position than with the flow control member in the second position, at least one of said portions being permanently magnetized; wherein the member further comprises a first surface that is acted on by fluid pressure at the first port, and a second surface that is acted on by fluid pressure at the third port; and wherein the magnetic material has sufficient magnetic power to move the member form the second position to the first position whenever the pressure at the third port is equal to the pressure at the first port.