Patent ID: 6367506
Filing Date: 2002-04-09
Classification: F16K,F25B,Y10T

Abstract:
A switch valve comprising:a single valve housing; a first passage formed in the valve housing to permit a fluid to flow into the valve housing; a second passage formed in the valve housing to permit, at selected times, the fluid in the first passage to exit the valve housing; a third passage formed in the valve housing to permit, at selected times, the fluid in the first passage to exit the valve housing; a first valve mechanism incorporated in the valve housing for selectively connecting and disconnecting the first passage with the second passage in accordance with an external instruction; and a second valve mechanism incorporated in the valve housing, wherein the second valve mechanism selectively connects and disconnects the first passage with the third passage in accordance with the difference between the pressure in the first passage and the pressure in the second passage when the first valve mechanism is closed, and wherein the second valve mechanism is always closed when the first valve mechanism is open.