Abstract: This thermostatic expansion valve (2) for heating-cooling refrigeration systems includes a body (4,8) having a transverse linear flow channel (10) therethrough. A tapered control valve element (12) divides the flow into identical inflow-outflow chambers (14,16) having equally sized inflow-outflow ports (22,24). The control valve element (12), when seated, prevents flow between the chambers (14,16), and is urged into a normally closed position by a biasing spring (26). A motor assembly (6) responsive to evaporator outlet pressure or compressor suction pressure, and temperature also controls movement of the valve element (12).

Abstract: This combination expansion valve and check valve (18) includes a valve body (22) having an inlet (24) and a outlet (26). A control valve (28) is disposed between the inlet and the outlet which controls flow through the valve when refrigerant flow is normal and pressure is higher at the inlet than the outlet. A by-pass conduit (60) is connected between the inlet and the outlet and includes an external conduit (62) and a passage (70) within the valve communicating with the outlet. A check valve (58) is disposed within the passage which selectively blocks flow through the conduit. The check valve includes a floating disc (66) moving between spaced check valve ports (61, 63) to block flow through the conduit when the expansion valve is operating and to permit flow through the conduit when flow is reversed. Two identical valves (18a) and (18b) are reversely connected to tandem to operate alternatively as expansion valves in a heat pump system (10).

Abstract: This refrigeration system expansion valve assembly (10) includes a valve body (12) having an upper portion (14) an intermediate portion (15) providing a valve chamber (17) and a valve port (18), and a lower portion (16). A valve inlet (20) and outlet (22) communicate with the valve chamber (17) on each side of the valve port (18). A piston assembly (24) is mounted in the body (12) for closing the valve port (18). The piston assembly (24) is actuated by a push rod assembly (26) driven by a stepper motor 28. The push rod assembly (26) includes a threaded member (102) slidingly and non-rotatively mounted in the body (12) and linearly driven by the motor shaft (30) which is threadedly received by said threaded member (102). The piston assembly (24) is urged into engagement with the push rod assembly (26) by a return spring (36) and includes a fluted nose portion (80) and a bleed passage (90, 92) communicating valve chamber (17) and the spring compartment (75).

Abstract: This expansion valve includes a valve body providing an inlet chamber and an outlet chamber separated by a compound valve. The compound valve includes a check valve seat defining a valve port receiving a check valve element and the check valve element includes a control valve port receiving a control valve element. During normal refrigerant flow conditions when the pressure in the inlet chamber is greater than the pressure in the outlet chamber, the check valve remains seated while the control valve element meters refrigerant flow between the two chambers. During reverse refrigerant flow, when the pressure in the inlet chamber is less than the pressure in the outlet chamber, the check valve is urged away from the check valve seat to provide for relatively unrestricted refrigerant flow between the two chambers.

Abstract: A thermostatic expansion valve particularly for use in a refrigeration system in which the refrigeration system includes a compressor, condenser, and evaporator operatively interconnected. The expansion valve includes a diaphragm for sensing a capillary pressure and a plurality of push rods for communicating the capillary pressure to a spring-biased valve member operatively associated with a valve seat. A piston in communication with the diaphragm has one end located in an inlet chamber and responds to an inlet chamber pressure. The piston, diaphragm, push rods and spring-biased valve member cooperate to provide a balanced flow of a refrigerant through the expansion valve without the piston or push rods substantially restricting or obstructing refrigerant flow through the expansion valve.

Abstract: A refrigeration control system for modulating an electrically-operated expansion valve in which a modulating, electrically-operated expansion valve is connected to the evaporator inlet, and first and second condition-responsive electrical sensors are positioned to respond to conditions at selected location in the system. An electrical amplifier circuit connects the condition-responsive electrical sensors to the valve for regulating the opening and closing of the valve in response to differences in the conditions sensed by the sensors. Refrigerant is fed to at least one of the sensors so as to cause modulation of the expansion valve. More particularly, the condition-responsive sensors are temperature-responsive, the first sensor being positioned to respond to the temperature of the liquid refrigerant expanded to suction pressure, and the second sensor being positioned to respond to suction line sensible temperature.

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.

Abstract: A refrigeration control system for modulating an electrically-operated expansion valve in which a modulating, electrically-operated expansion valve is connected to the evaporator inlet, and first and second condition-responsive electrical sensors are positioned to respond to conditions at selected location in the system. An electrical amplifier circuit connects the condition-responsive electrical sensors to the valve for regulating the opening and closing of the valve in response to differences in the conditions sensed by the sensors. Refrigerant is fed to at least one of the sensors so as to cause modulation of the expansion valve. More particularly, the condition-responsive sensors are temperature-responsive, the first sensor being positioned to respond to the temperature of the liquid refrigerant expanded to suction pressure, and the second sensor being positioned to respond to suction line sensible temperature.

Abstract: A refrigeration control system for modulating an electrically-operated expansion valve in which a modulating, electrically-operated expansion valve is connected to the evaporator inlet, and first and second condition-responsive electrical sensors are positioned to respond to conditions at selected location in the system. An electrical amplifier circuit connects the condition-responsive electrical sensors to the valve for regulating the opening and closing of the valve in response to differences in the conditions sensed by the sensors. Refrigerant is fed to at least one of the sensors so as to cause modulation of the expansion valve. More particularly, the condition-responsive sensors are temperature-responsive, the first sensor being positioned to respond to the temperature of the liquid refrigerant expanded to suction pressure, and the second sensor being positioned to respond to suction line sensible temperature.

Abstract: A filter-drier unit adapted for bidirectional flow in heat pump systems. This filter-drier unit includes a shell having opposed flow ports. Spaced partitions in the shell provide a compartment therebetween, each partition separating a flow port from the compartment. An outlet check valve is connected to each partition, and a perforated tube in the compartment, extends between and interconnects the outlet check valves. A molded desiccant core in the compartment, is disposed about the tube. An inlet check valve is connected to each partition in laterally spaced relation to the outlet check valve connected to the same partition to control the flow from each flow port through an inlet check valve in one partition and into the compartment, through the core and tube thence through an outlet check valve in the other partition, and out the other flow port.

Abstract: A filter-drier unit for heat pump systems in which desiccant is located in a housing between an inlet and an outlet, a screen is provided in the housing between the inlet and desiccant for enabling a first flow from the inlet through the screen and desiccant, and a passage is provided for bypassing the desiccant and enabling a second flow from the inlet through the bypass passage, the screen collecting the desiccant upon any reverse flow for precluding migration of desiccant out of the inlet. The screen is located relative to the inlet and bypass passage so that the second flow engages and moves past the screen for washing the screen. A filter is provided in the housing between the desiccant and outlet for receiving the first flow through the desiccant and for receiving the second flow from the bypass passage prior to movement through the outlet.

Abstract: A filter-drier assembly adapted for bidirectional flow in heat pump systems. The filter-drier assembly includes a pair of bypass lines in the liquid line, each bypass line circumventing one of the expansion devices located in the liquid line. An expansion device is located ahead of the outdoor coil for use in one mode of operation and a second expansion device is located ahead of the indoor coil for use in the other mode of operation. A filter-drier unit is disposed in each bypass line, each filter-drier unit including a check valve enabling flow through the associated bypass line and filter-drier unit in one direction and precluding flow in the opposite direction. The check valve of each filter-drier unit precludes flow in the bypass line when its associated expansion device is operable in one mode of operation. The filter-drier unit includes a shell provided with an inlet and an outlet, and filtering and drying elements in the shell between the inlet and outlet.

Abstract: A filter-drier unit adapted for bidirectional flow in heat pump systems. This filter-drier unit includes an individual filter-drier in each compartment formed on opposite sides of a partition in a shell. A conduit connects the inlet of each filter-drier with the compartment other than the one in which the filter-drier is located. A check valve is connected to the outlet of each filter-drier to enable flow into the compartment in which the filter-drier is located and to preclude backflow, whereby flow into either one of the compartments through an associated shell port passes by the filter-drier in the said one compartment and through the inlet of the filter-drier in the other compartment, and thence into the said other compartment and out through its associated shell port. In one embodiment, the individual filter-driers and the fittings attaching the filter-driers to the partition are relatively laterally offset in the shell.