Abstract: This thermostatic expansion valve (12) includes inlet and outlet fittings (22 and 24) connected to a valve body (30) having a diaphragm assembly (40) at one end. A replaceable cartridge (50) is disposed in the valve body (30) below the diaphragm assembly (40) having a passage (58) communicating with the inlet (22) and an end opening of predetermined size to define a valve port (60). A pin (72) is disposed below the valve port (60) and connected to the diaphragm assembly (40) by a pair of pushrods (76) so that the pin assembly (70) responds to modulation of the diaphragm assembly. A spring assembly (80) engages the pin assembly (70) tending to urge said assembly into a closed position.

Abstract: This control valve (10) can be used for reducing the temperature of the discharge gas in the compressor (100) of a refrigeration system. The valve (10) includes a body (12) having inlet and outlet ports (20, 22), respectively receiving refrigerant from one part of the system and injecting it to a point upstream of compressor discharge, a valve seat (32), disposed between said inlet and outlet ports, and a valve member (34) controlling flow through the valve seat. The valve (10) includes a spring assembly (40) mounted in the body (12) and applying a force to the valve member (34) tending to urge the valve member into a closed position and an actuator assembly (50) modulating the valve member (34) in response to a change of temperature in the compressor discharge line. The actuator assembly (50) includes an actuator (52) movable within the body (12), a connector (70) attached to the body, a bellows (60) connected between the actuator (52) and the connector (70).

Abstract: A pilot-operated pressured regulator valve includes a main valve for controlling refrigerant flow in a refrigeration suction line. A pilot valve which is responsive to evaporator pressure controls a flow of high pressure refrigerant to the main valve for modulating the main valve. A bleed is provided for bleeding the high pressure refrigerant from the main valve. A solenoid-actuated shut-off valve controls the bleed flow from the main valve. The shut-off valve is selectively closed for maintaining the high pressure refrigerant in the main valve for closing the main valve. A bleed flow of high pressure is provided to the main valve when the shut-off valve is closed in order to maintain the main valve closed.