Patent ID: 7007713
Filing Date: 2006-03-07
Classification: G05D,Y10T

Abstract:
1. A pressure control apparatus comprising: a pressure control apparatus body; a main valve and a diaphragm provided in said pressure control apparatus body; a directional control valve provided in connection with said pressure control apparatus body; a passage for communication between a supply port and an output port, said main valve being disposed in said passage; a diaphragm chamber formed by said diaphragm; a valve spring for urging said main valve in a direction in which it is closed; and a pressure regulating spring acting on said diaphragm to urge said main valve in a direction in which it opens, wherein force acting on said diaphragm changes in accordance with a switching operation of said directional control valve, and hence a pressure at said output port changes; wherein said diaphragm chamber and a small output port of said directional control valve are communicated with each other, and in accordance with the switching operation of said directional control valve, said diaphragm chamber is placed at a secondary pressure of said output port or at an atmospheric pressure, wherein when said diaphragm chamber is at the secondary pressure, a primary pressure flows to said output port after being reduced to a set pressure by said main valve, and when said diaphragm chamber is at the atmospheric pressure, said main valve fully opens.