The present invention pertains to a thermal expansion valve for a heat exchanger with at least one header. The valve includes a valve block and a superheat defining mechanism. The valve block includes a high pressure inlet, a low pressure outlet, a first suction gas port and a second suction gas port. A contact surface for coupling the valve to the header includes at least one cylindrical portion of the valve block. The invention is also directed at a heat exchanger with a corresponding thermal expansion valve.

The present invention pertains to a thermal expansion valve for a heat exchanger with at least one header. The valve includes a valve block and a superheat defining mechanism. The valve block includes a high pressure inlet, a low pressure outlet, a first suction gas port and a second suction gas port. A contact surface for coupling the valve to the header includes at least one cylindrical portion of the valve block. The invention is also directed at a heat exchanger with a corresponding thermal expansion valve.

A Heating, Ventilation, and Air Conditioning (HVAC) system that is configured to receive a refrigerant from a condenser at a fixed expansion device and a variable expansion device. The system is further configured to output a first portion of the refrigerant to a first downstream HVAC component at a fixed flow rate using the fixed expansion device. The system is further configured to sense a temperature of an evaporator using a sensing bulb and to apply a first force to a pin of the variable expansion device based on the sensed temperature. The system is further configured to apply a second force to a valve of the variable expansion device via the force applied to the pin and to output a second portion of the refrigerant to a second downstream HVAC component at a variable flow rate based on the second force using the valve of the variable expansion device.

An ejector refrigeration cycle device includes: a radiator that dissipates heat from a refrigerant discharged from a compressor; an ejector module that decompresses the refrigerant cooled by the radiator; and an evaporator that evaporates a liquid-phase refrigerant separated in a gas-liquid separation space of the ejector module. A grille shutter is disposed as an inflow-pressure increasing portion between the radiator and a cooling fan blowing the outside air toward the radiator. The grille shutter is operated to decrease the volume of the outside air to be blown toward the radiator when an outside air temperature is equal to or lower than a reference outside air temperature, thereby increasing the pressure of the inflow refrigerant to flow into a nozzle passage of the ejector module.

Systems, devices, and methods are presented that include an expansion valve having a pin operable to regulate a primary flow of refrigerant through a flow orifice. A flange is coupled to the pin and is configured to regulate a bleed flow of refrigerant through a bleed orifice. The flange moves cooperatively with the pin, thereby enabling the bleed flow of refrigerant to vary in coordination with the primary flow of refrigerant. When the pin occludes the flow orifice, the flange forms a predetermined gap that allows a non-zero bleed flow when the primary flow of refrigerant is substantially zero. The bleed flow of refrigerant therefore flows persistently through the expansion valve during operation. Other systems, tools and methods are presented.

An expansion valve includes: a body having an insertion hole in a partition separating a first passage from a second passage; a power element configured to generate a drive force for opening or closing a valve section; a shaft extending through the insertion hole and configured to transmit the drive force to a valve element; a vibration-proof spring coaxially supporting the shaft and biasing the shaft radially inward to apply a sliding resistance thereto; and a flexible O-ring supported by one of an inner surface of the support part defining the insertion hole and an outer surface of the shaft and being in close contact with the other thereof. The O-ring, sliding portions of the shaft and the support part, and the vibration-proof spring are arranged in this order from a first passage side toward a second passage side in an axial direction of the shaft.

A temperature sensitive rod is communicated with a diaphragm that is displaceable in response to a pressure difference between an internal pressure of a sealed space, in which a temperature sensitive medium is sealed, and a pressure of a low pressure refrigerant outputted from an evaporator. A blind hole, which opens to the sealed space, is formed in an inside of the temperature sensitive rod. The temperature sensitive medium is a mixture gas of the refrigerant and an inert gas. A mixing ratio of the inert gas in the temperature sensitive medium corresponds to a ratio of an equivalent diameter of the blind hole relative to a depth of the blind hole in such a manner that a time constant of heat conduction from the temperature sensitive rod to the temperature sensitive medium is kept within a desired time constant range.

A refrigerant/heat medium heat exchanger that heats a heat medium which circulates in a heater core of an HVAC unit is provided in a discharge pipe of a cooling refrigerant circuit, a heating bypass circuit that extends to a receiver is connected to a downstream side of the refrigerant/heat medium heat exchanger through a switching means, a second circuit having a second decompression means is provided between an outlet of the receiver and a first end of a vehicle exterior heat exchanger, and a third circuit having a solenoid valve is provided between a second end of the vehicle exterior heat exchanger and an intake circuit. In a vehicle air-conditioning system, a heating refrigerant circuit is configured by an electric compressor, a refrigerant/heat medium heat exchanger, a switching means, a heating bypass circuit, a receiver, a second circuit, a vehicle exterior heat exchanger, and a third circuit. Consequently, while simplification of a configuration and the like are attained by diverting cooling refrigerant circuit and an HVAC of a current system, cooling/heating capacity can be ensured by diversifying heating heat sources, and operation in a frost formation delay mode or the like is possible during heating.

A heat pump system for a vehicle delays the change of the direction of a directional valve for a given period of time and then conducts the change of the direction of the directional valve, upon receiving the mode change signal between an air conditioner mode and a heat pump mode, thus preventing the generation of the noise and vibration caused by the differential pressure of a refrigerant.

Provided is a diaphragm-actuated fluid control valve capable of, even in a region where the pressure difference between the pressures on the upper surface side and the lower surface side of a diaphragm is small, significantly changing the amount of lift of the diaphragm relative to the change in the pressure difference, without reducing the thickness of the diaphragm, and thus is capable of providing a predetermined flow rate and performing stable flow rate control. The control valve has a diaphragm 35 for driving a valve 25. The diaphragm 35 has a mountainous-wave portion 35b formed between an outermost portion 35a and an innermost portion 35c thereof, the mountainous-wave portion having the shape of concentric circles when viewed in a plan view and having N+(0.25 to 0.75) elevated portions that protrude upward or downward when viewed in cross section, where N is a positive integer (1, 2, 3, . . . ).