Integrated control valve for a variable capacity compressor

摘要

An integrated capacity control valve (10) for a variable capacity refrigerant compressor includes an integral pressure sensor (74) that is continuously coupled to a discharge port (14) of the valve for measuring the refrigerant discharge pressure. A plunger (30) of the control valve is disposed within a passage (24) coupling the compressor crankcase (16) to the discharge port (14), and is positioned by pneumatic and electric control elements (26, 44) to regulate the refrigerant suction pressure. The plunger (30) has intersecting axial and lateral bores (72, 70) that define a continuous passage between the discharge port (14) and a cavity (60) in which the pressure sensor (74) is retained so that the sensor (74) is continuously exposed to the discharge pressure regardless of the plunger position, and refrigerant discharge pressure in the lateral bore (70) produces a bias force on the plunger (30) that compensates the pneumatic suction pressure setpoint for a pressure drop between the evaporator and the suction port (12) of the valve (10).