Abstract: A refrigeration cycle apparatus includes an expander-compressor unit (1) having a first motor (12), a second compressor (2) having a second motor (22), and a controller (7). The controller (7) determines the target rotational frequency F1 of the first motor (12) and the target rotational frequency F2 of the second motor (22) for a start-up operation, and determines whether the opening X of an injection valve (61) should be in a fully opened state or in a fully closed state during the start-up operation, based on an outside air temperature and other factors. Then, the controller (7) performs the start-up operation by controlling the rotational frequencies f1 and f2 of the first motor and the second motor to be the determined target rotational frequencies F1 and F2 while maintaining the opening X of the injection valve in the fully opened state or in the fully closed state.

Abstract: A control method regulates an electronic expansion valve of a chiller to maintain the refrigerant leaving a DX evaporator at a desired or target superheat that is minimally above saturation. The expansion valve is controlled to convey a desired mass flow rate, wherein valve adjustments are based on the actual mass flow rate times a ratio of a desired saturation pressure to the suction pressure of the chiller. The suction temperature helps determine the desired saturation pressure. A temperature-related variable is asymmetrically filtered to provide the expansion valve with appropriate responsiveness depending on whether the chiller is operating in a superheated range, a saturation range, or in a desired range between the two.

Abstract: An air conditioning apparatus includes a refrigeration cycle, a magnetic field generator, a detector and a control part. The refrigeration cycle has a compression element, a refrigerant tube in thermal contact with a refrigerant flowing through the refrigerant tube and/or a heat-generating member in thermal contact with a refrigerant flowing through the refrigerant tube. The magnetic field generator generates a magnetic field to inductively heat the heat-generating member. The detector detects either temperature or temperature change or pressure or pressure change in refrigerant flowing through a predetermined portion of the refrigeration cycle. The control part permits magnetic field generation in a first compression element state and a higher output second compression element state, and when a magnetic-field-generating-permission condition is satisfied. The condition is either that a value detected by the detector change or that a change be detected in the value detected by the detector.

Abstract: An air conditioning apparatus includes a compression element, a refrigerant cooler, an expansion element, a refrigerant heater, a magnetic field generator, a generated heat temperature sensor and a control part. The magnetic field generator generates a magnetic field in order to induction-heat a refrigerant tube circulating refrigerant and/or a member in thermal contact with refrigerant flowing through the refrigerant tube. The generated heat temperature sensor senses temperature of a portion that generates heat due to the induction heating. The control part performs superheating protection control in order to increase an opening degree of the expansion mechanism when the temperature sensed by the generated heat temperature sensor reaches or exceeds a predetermined generated heat temperature, or when a rate of increase of the temperature sensed by the generated heat temperature sensor reaches or exceeds a predetermined rate of increase.

Abstract: An indoor unit of an air conditioner with an electronic expansion valve. The indoor unit includes a main body, a heat exchanger disposed at the front portion of the inside of the main body, a control unit, in which electrical components are mounted, disposed at the outside in the lengthwise direction of the heat exchanger, a control case including a first side surface part disposed between the control unit and the heat exchanger and an extension part connected with the first side surface part and extended in the lengthwise direction of the heat exchanger, and an electronic expansion valve disposed in a space defined by two surfaces neighboring with each other by the extension part.

Abstract: A heat pump is provided having a first heat exchanger and a second heat exchanger. A compressor is fluidly coupled to the first heat exchanger and the second heat exchanger. A reversing valve is fluidly coupled between the first heat exchanger and the second heat exchanger. The reversing valve is adapted to flow of a refrigerant from the compressor to the first heat exchanger during heating mode and to the second heat exchanger during a cooling mode. A thermal expansion valve is positioned between the first heat exchanger and the second heat exchanger. An electronic expansion valve is positioned between the first heat exchanger and the second heat exchanger. A controller is electrically coupled to operate the electronic expansion valve between a fully open, a fully closed and a modulated position depending on the operation of the compressor.

Abstract: A refrigerating cycle apparatus is obtained that can determine excess/shortage of a refrigerant amount in a refrigerating circuit at high precision even if a factor such as a heat exchanger whose refrigerant amount is difficult to calculate exists.

Abstract: A heat pump system includes: a heat-source-side refrigerant circuit having a heat-source-side compressor, a first usage-side heat exchanger operable as a radiator of heat-source-side refrigerant, and a heat-source-side heat exchanger operable as a radiator of heat-source-side refrigerant; and a usage-side refrigerant circuit having a usage-side compressor, a refrigerant/water heat exchanger operable as a radiator of usage-side refrigerant to heat an aqueous medium, and the first usage-side heat exchanger operable as an evaporator of usage-side refrigerant by radiation of heat-source-side refrigerant.

Abstract: Refrigeration circuit (2) for circulating a refrigerant in a predetermined flow direction, having in flow direction a heat rejecting heat exchanger (4), an evaporator throttle valve (8), an evaporator (10), a compressor (22), an internal heat exchanger (16) placed with its “cool side” between the evaporator (10) and the compressor (22), an inlet temperature sensor (24) located between the evaporator (10) and the internal heat exchanger (16) and an outlet temperature sensor (26) located between the internal heat exchanger (16) and the compressor (22), and a control (28) for controlling the evaporator throttle valve (8) based on the inlet and outlet temperature sensor measurement, wherein the control is adapted for controlling the evaporator throttle valve (8) based on an inlet temperature setpoint at the inlet temperature sensor (24); and shifting the inlet temperature setpoint based on the outlet temperature sensor measurement (26).

Abstract: An expansion valve of the present invention has a structure which integrates a refrigerant flow divider. The expansion valve includes a refrigerant flow dividing chamber 6 on the downstream side of a first throttle 10. Flow dividing tubes 12 are connected to the refrigerant flow dividing chamber 6. In the expansion valve, refrigerant which has passed through the first throttle 10 is sprayed into the refrigerant flow dividing chamber 6, so that the flow dividing characteristic of the refrigerant is improved. Also, due to an enlargement of the passage in the refrigerant flow dividing chamber 6, the ejection energy of a flow of the refrigerant ejected from the first throttle 10 is dispersed, whereby a discontinuous refrigerant flow noise is reduced.

Abstract: An expansion valve for an air conditioning system circulates refrigerant through a fixed-displacement compressor, a condenser, and an evaporator. An inlet is provided for receiving refrigerant liquefied in the condenser. An outlet of the expansion valve supplies refrigerant to the evaporator. A valve element controls flow of refrigerant between the inlet and the outlet, wherein the valve element is normally closed. A control assembly is coupled to the valve element and is responsive to at least one temperature or pressure in the air conditioning system to open the valve element to variably meter the refrigerant to the evaporator. A bleed passage bypasses the valve element to conduct refrigerant between the inlet and the outlet.

Abstract: If an operation command is received from any of the indoor units when the initialization of the corresponding electronic expansion valves is not completed. First, initialization is performed on the electronic expansion valve corresponding to the indoor unit which has issued an operation command. When the initialization has been performed on the electronic expansion valves corresponding to all of the indoor units which have issued an operation command, the flow proceeds to a processing step for a compressor. Then, the electronic expansion valves which have been initialized are adjusted to a predetermined operational opening degree. After this step is completed, the electronic expansion vales corresponding indoor units which have issued no operation command and whose initialization has not been completed are initialized and adjusted to a predetermined opening degree. This leads to a reduced loss of time until the compressor is activated after the electronic expansion valves are initialized.

Abstract: To obtain an air-conditioning apparatus that does not make a refrigerant circulate up to an indoor unit and further can achieve energy-saving. A refrigeration cycle is configured by connecting a compressor that pressurizes a refrigerant, a four-way valve that switches a circulation path of the refrigerant, a heat source side heat exchanger that performs heat exchange, expansion valves for pressure-adjusting the refrigerant, and a plurality of intermediate heat exchangers that performs heat exchange between the refrigerant and the heat medium to heat and cool the heat medium, with piping. A heat medium circuit is configured by connecting intermediate heat exchangers, pumps that pressurize the heat medium, and a plurality of use side heat exchangers that perform heat exchange between the heat medium and the air in the indoor space, with piping.

Abstract: A refrigeration cycle apparatus 100 includes a low-pressure compressor 113, a high-pressure compressor 101, a radiator 103, a gas-liquid separator 107, an expansion valve 109, an expander 105 and an evaporator 111. The low-pressure compressor 113 and the expander 105 are coupled by a shaft 116, and the low-pressure compressor 113 is driven using power recovered by the expander 105 from a refrigerant. The low-pressure compressor 113 and the high-pressure compressor 101 are serially connected by an intermediate-pressure flow path 114. The gas-liquid separator 107 and the intermediate-pressure flow path 114 are connected by the reciprocating flow path 115. The reciprocating flow path 115 is configured to allow the refrigerant to circulate bidirectionally. It is possible to regulate the refrigerant flow rate in the reciprocating flow path 115 by controlling the opening degree of the expansion valve 109.

Abstract: An air conditioning apparatus includes a refrigerant circuit and an operation control section. The operation control section is capable of performing a refrigeration cycle for causing an outdoor heat exchanger to function as a refrigerant condenser and an indoor heat exchanger to function as a refrigerant evaporator, while performing superheat degree control for controlling the aperture of an indoor expansion valve so that the degree of superheat of the refrigerant at the outlet from the indoor heat exchanger is constant. The operation control section means sets a lower aperture limit for the indoor expansion valve to perform the superheat degree control, and reduces the lower aperture limit when the refrigerant at the outlet from the indoor heat exchanger is detected to be wet.

Abstract: Disclosed here is an air conditioner and the control method thereof comprising an outdoor unit having an outdoor heat exchanger for the heat exchanging of the outdoor air and refrigerant; at least one indoor unit corresponding to the outdoor unit and having indoor heat exchanger for the heat exchanging of the room air and refrigerant; an expansion valve installed on the refrigerant pipe connecting the outdoor heat exchanger and the indoor heat exchanger, and expanding the refrigerant; and a control device controlling the opening speed of the expansion valve in accordance with the operation modes of the indoor unit.

Abstract: An air conditioner is provided that may minimize lengths of pipes connecting a plurality of indoor devices and an outdoor device, facilitate connection between respective refrigerant pipes through a distribution device, and omit a separate cable to transmit/receive a control signal between the plurality of indoor devices and the distribution device.

Abstract: A heat transfer system and method for maintaining or controlling a temperature of a device under test (DUT) with heat generating capability. The heat transfer system comprises a temperature control unit (TCU) for thermal coupling to the DUT, the TCU arranged for flow of a heat transfer medium therethrough; an automatic expansion valve disposed upstream of the TCU; a flow-regulating valve disposed downstream of the TCU; and a controller coupled to the TCU for receiving an input signal representative of a temperature of the DUT; wherein the controller is further coupled to the flow-regulating valve to change a flow area of the flow-regulating valve based on the signal representative of the temperature of the DUT.

Abstract: A method of controlling an air conditioner includes a step of controlling an opening degree of the expansion valve and/or the number of rotations of an outdoor fan of the outdoor heat exchanger such that the difference Tx (=Te?Ti) between the temperature Te of the outdoor heat exchanger and the temperature Ti of the indoor heat exchanger is within a predetermined range, in a cooling mode in a low outside air temperature environment. Specifically, the opening degree of the expansion valve is adjusted, with the number of rotations of the outdoor fan being reduced to be smaller than that in a normal cooling mode, and then, the number of rotations of the outdoor fan is adjusted with the opening degree of the expansion valve being fixed, thereby controlling the difference Tx to be substantially constant.

Abstract: Disclosed herein are an air conditioner which controls a pressure of a refrigerant of an outdoor unit by adjusting an opening degree of an outdoor expansion valve or an indoor expansion valve, and a control method thereof. The air conditioner measures a pressure of the refrigerant discharged from a compressor during a cooling operation, and raises the pressure of the refrigerant to be higher than a designated pressure by controlling an opening degree of at least one of the outdoor expansion valve and the indoor expansion valve, if the pressure of the refrigerant is lower than the designated pressure. Further, the air conditioner measures the pressure of the refrigerant inhaled into the compressor during a heating operation, and adjusts the pressure of the refrigerant to be lower than a designated pressure by controlling the opening degree of the outdoor expansion valve, if the pressure of the refrigerant is higher than the designated pressure.

Abstract: Disclosed herein is a water-source heat-pump type air conditioner in which a receiver is connected to a super-cooler or economizer, and a control method of the air conditioner to reduce the quantity of liquid refrigerant collected in the receiver during a cooling/heating overload operation. When a cooling/heating overload operation occurs, an electric expansion valve associated with the super-cooler or the economizer is opened by a predetermined opening degree, to bypass high-pressure liquid refrigerant collected in the receiver, thereby preventing a rapid pressure increase due to a great quantity of liquid refrigerant collected in the receiver.

Abstract: A refrigerant system is provided. The refrigerant system may use an electronic expansion valve that electronically controls an opening degree thereof, as a high-pressure valve and a low-pressure valve to selectively block a high-pressure branch valve and a low-pressure branch valve. Accordingly, noise transmitted to an interior space may be minimized when the operation mode of the refrigerant system is switched. In addition, the structure of the refrigerant system may be simplified.

Abstract: A control apparatus and associated method for a refrigeration system are provided. The control apparatus includes sensors capable of detecting controlled refrigerator zone temperatures and superheat levels of refrigerant vapour exiting an evaporator. The control module receives input from the sensors, compares the input to a determined controlled refrigerator zone set point and a learned superheat level, and generates an output with respect thereto. In particular the output modulates an electronic evaporator pressure regulating (EEPR) valve between an open and a closed position in response to detecting abnormal operation of the thermostatic expansion valve or electronic expansion valve.

Abstract: A subcool flow control valve useful in a refrigerant system includes an enclosure having a fluid flow pathway for a controlled fluid between an inlet and an outlet. A thermally conductive flexible wall forms a sealed cavity within the enclosure for carrying a controlling fluid. A metering orifice operable between the pathway and the outlet port controls an amount of metered fluid passing through the outlet port in response to movement of the flexible wall toward and away from the metering orifice in response to temperature changes of the controlled fluid transmitting temperature and thus pressure changes to the controlling fluid in the sealed cavity. Inverse thermal feedback means is formed as part of the valve for stabilizing valve operation thus providing means for transmitting a thermal signal from the metered controlled fluid back to the controlling fluid.

Abstract: A device for cooling a heat source of a motor vehicle is provided that includes a cooling body which has a plurality of feed flow channels and a plurality of return flow channels. At least a multiplicity of the feed flow channels and return flow channels are arranged adjacent to one another in an alternating fashion in the cooling body.

Abstract: A refrigeration system for a frozen product dispenser is controlled to have a variable cooling capacity that is determined by variable cooling load demands of the dispenser. This is accomplished, in part, by providing the refrigeration system with a variable speed compressor and one or more adjustable expansion valves for metering refrigerant to associated evaporators that are heat exchange coupled to associated freeze barrels of the dispenser, and by controlling the metering setting of the expansion valves and the speed of operation of the compressor in accordance with the cooling load demands of the dispenser. The arrangement provides for efficient operation of the refrigeration system from an energy standpoint and for a reduction in on/off cycling of the system.

Abstract: A method for dehumidification and controlling system pressure in a refrigeration system includes providing a refrigeration system having a compressor, a condenser and an evaporator connected in a closed refrigerant loop. Each of the condenser and evaporator have a plurality of refrigerant circuits. A first heat transfer fluid is flowed over the condenser and a second heat transfer fluid is flowed over the evaporator. At least one of the refrigerant circuits of the condenser is isolated to provide a decreased amount of heat transfer area within the condenser and to increase the refrigerant pressure within the refrigeration system when the refrigerant pressure within the refrigeration system is at or below a predetermined pressure. At least one of the refrigerant circuits of the evaporator is isolated to dehumidify and maintain the temperature of the second heat transfer fluid at or above a predetermined temperature when dehumidification is required.

Abstract: A vapor expansion system includes a normally closed pneumatic valve between the evaporator and the turbine inlet, with the valve being selectively actuated by the flow of refrigerant vapor from the evaporator so as to enable opening the valve only during periods in which sufficient pressure has built up in the evaporator to properly operate the turbine. A bypass line has a normally open pneumatic valve with an actuator that is similarly caused to operate by pressurized refrigerant vapor from the evaporator. Both actuators are vented to the condenser such that the refrigerant vapor vented from the actuator does not escape to ambient.

Abstract: The present invention relates to an air conditioner and method for controlling the same, which can continue an operation when a sensor breaks down. A method for controlling an air conditioner according to the exemplary embodiment of the present invention comprises a plurality of indoor units, wherein the method comprises occurring a breakdown in a sensor of any one of the plurality of indoor units, calculating a value of the sensor, and controlling the indoor unit according to the calculated value of the sensor.

Abstract: A device for cooling a coolant, for cooling a charging fluid for charging an internal combustion engine is provided that includes a refrigerant guide, particularly a refrigerant circuit, and a coolant guide, particularly a coolant circuit; wherein the refrigerant guide comprises a first evaporator for a refrigerant for cooling an ambient air and a second evaporator for a refrigerant for cooling the coolant, the coolant guide comprises a heat exchanger for the charging fluid, a coolant cooler, and the second evaporator for the refrigerant of the refrigerant guide for cooling the coolant. In a first variant, the first and the second evaporator are disposed in series in the refrigerant guide. In a second variant, the first evaporator and the second evaporator are disposed in parallel in the refrigerant guide, particularly wherein a suction throttle is disposed downstream in the refrigerant flow after the second evaporator.

Abstract: A carbon dioxide refrigerant vapor compression system and method of operating that system are provided. The refrigerant vapor compression system includes a compression device, a flash tank receiver disposed in the refrigerant circuit intermediate a refrigerant heat rejection heat exchanger and a refrigerant heat absorption heat exchanger, and a compressor unload circuit including a refrigerant line establishing refrigerant flow communication between an intermediate pressure stage of the compression device and the refrigerant circuit at a location downstream of the refrigerant heat absorption heat exchanger and upstream of a suction inlet to the compression device, and a unload circuit flow control device disposed in said unload circuit refrigerant line. In response to at least one system operating parameter sensed by at least one sensor, the controller selectively positions the unload flow control device to maintain the refrigerant vapor compression system operating below a preselected high pressure limit.

Abstract: Provided is a refrigerant cycle of an air conditioner for vehicles, and more particularly, a refrigerant cycle of an air conditioner for vehicles having a first evaporating unit and a second evaporating unit disposed upstream and downstream in a direction in which air blown from a single blower flows to control an amount of the refrigerant supplied to each evaporating unit, thereby making it possible to obtain optimal radiating performance (cooling performance) and cooling efficiency (COP) through the design of the optimal refrigerant flow ratio depending on the cooling load.

Abstract: In a refrigeration system having a compressor, a condenser, an evaporator, and a controller for controlling an expansion valve, a process for controlling compressor discharge during a cooling cycle comprising the steps of monitoring a compressor discharge parameter, comparing the compressor discharge parameter to a set point stored in a controller memory, and selectively operating the expansion valve upstream of the evaporator in response to a difference between the compressor discharge parameter and the set point.

Abstract: A first expansion valve is provided in an outdoor unit, and a second expansion valve is provided in an indoor unit. A pipe line connects a first joint pipe of the first expansion valve and a second joint pipe of the second expansion valve. When a refrigerant flows in from the second joint pipe and flows out from the first joint pipe, the first and second expansion valves are in a full open state due to pressure of the refrigerant. When the refrigerant flows in from the first joint pipe and flows out from the second joint pipe, the first and second expansion valves are in semi-closed state (flow rate controlling state). In a cooling mode, the second expansion valve expands the refrigerant just before an indoor heat exchanger, and in a heating mode, the first expansion valve expands the refrigerant just before an outdoor heat exchanger. In both heating and cooling mode, a large amount of refrigerant flows through the pipe line to reduce pressure loss.

Abstract: A heat pump according to the present invention comprises a plurality of the compression chambers, and compresses refrigerant with multistage, and injects vapor refrigerant into the space between the plurality of the compression chambers by using the first refrigerant injection flow path and the second refrigerant injection flow path. Performance and efficiency of the heat pump can be improved compared with non-injection, as flow rate of the refrigerant circulating the indoor heat exchanger is increased. Thus heating performance can be improved also in the extremely cold environmental condition such as the cold area by increasing the injection flow rate. Also, because the heat pump according to the present invention comprises the first refrigerant injection flow path and the second refrigerant injection flow path, refrigerant is injected twice. Thus, as the injection flow rate of the refrigerant is increased, heating capacity can be improved.

Abstract: Provided is a multi-evaporation system which carries out a multi-evaporation process in an air-conditioning cycle of a vehicle air conditioning system, thereby enhancing system efficiency. The multi-evaporation system includes a compressor 10 which sucks and compresses refrigerant; a condenser 20 which condenses the refrigerant compressed in the compressor 10; an expanding means 30 which receives the refrigerant condensed in the condenser 20 through an inlet port 31, branches the refrigerant into at lest two or more, discharges the refrigerant through at least two or more discharging part 32a to 32n, and throttles the refrigerant before or after the refrigerant is branched; and an evaporator 40 which comprises at least two or more evaporating parts 41 to 4N so as to receive and evaporate the refrigerant discharged from the expanding means 30 and then introduce the evaporated refrigerant into the compressor 10.

Abstract: A vehicle air-conditioning apparatus, including: a refrigerant circulation channel that flows a refrigerant, the refrigerant circulation channel provided in a refrigeration cycle system including, as connected in a cyclic pattern, a compressor for the refrigerant, an outdoor heat-exchanger exchanging heat between the refrigerant and an outdoor air, an expansion valve reducing pressure of the refrigerant, and an air-conditioning heat-exchange circuit exchanging heat between the refrigerant and air to be introduced into a vehicle interior; and an equipment heat-exchange circuit connected in parallel to the circuit and exchanging heat between the refrigerant and in-vehicle equipment. The circuit includes a cooling heat-transfer medium circulation channel that circulates a heat-transfer medium for cooling.

Abstract: The present invention relates to an aircraft cooling system evaporator arrangement (10) with at least two mutually independent circuits (20a, 20b) for a coolant, at least two evaporation devices (12a, 12b) arranged to be hydraulically parallel for enabling an exchange of heat between the coolant and a refrigerant, at least two supply lines (18a, 18b) for supplying refrigerant to the evaporation devices (12a, 12b), and at least two discharge lines (22a, 22b) for discharging refrigerant from the evaporation devices (12a, 12b). One of the evaporation devices (12a, 12b), one of the supply lines (18a, 18b) and one of the discharge lines (22a, 22b) is assigned to each coolant circuit (20a, 20b).

Abstract: A DX heating/cooling system includes an automatic hot gas by-pass valve (1) for preventing frosting of an interior heat exchanger/air handler (6) when the system is switched from the heating mode to the cooling mode, and a specially sized TXV (7) by-pass refrigerant flow means (12), where the automatic hot gas by-pass valve (1) is positioned to provide hot gas at two optional locations, with one location before the cool liquid enters the air handler (6), and with the other location after the warmed vapor refrigerant exits the air handler (6).

Abstract: Disclosed are an air conditioning system and a method for controlling an operation thereof, whereby a charging device for charging power to be supplied into the indoor unit is employed, a chargeable control unit is separately employed, or a separate control unit connectable between the indoor unit and an electronic expansion valve is employed, thereby closing the electronic expansion valve even if power supplied into the indoor unit is blocked while controlling opening and closing of the electronic expansion valve, and additionally preventing the electronic expansion valve from being left open, resulting in prevention of an overload of a compressor within an indoor unit.

Abstract: A refrigeration cycle device 100 where a combustible refrigerant circulates includes a bypass pipe 5 that is connected so that part of the refrigerant that flows through a circulation pipe extending from a condenser 2 to a flow control valve 3 bypasses the flow control valve 3 and an evaporator 4; a bypass flow control valve 6 that controls the amount of the refrigerant flowing through the bypass pipe 5; a heat exchanger 7 that allows heat exchange between the refrigerant that flows through the bypass pipe 5 after flowing out of the bypass flow control valve 6 and the refrigerant that flows through the circulation pipe after flowing out of the condenser 2; and a subcooling degree sensor T73 that detects the subcooling degree of the refrigerant at the inlet of the flow control valve 3.

Abstract: An air conditioning system can improve the cooling/heating performance of the system because the injection of refrigerant into the compressor is achieved. The air conditioning system can further improve the cooling/heating performance in a low temperature region by injecting refrigerant as a two-phase refrigerant or a superheated vapor state into the compressor. The air conditioning system can prevent damage of the compressor and further improve reliability by controlling such that the ratio of a liquid refrigerant in the refrigerant injected into the compressor may be less than a set value.

Abstract: A heat pump apparatus includes: a refrigerant circuit which includes a compressor, a utilization-side heat exchanger for exchanging heat between water and refrigerant, an electronic expansion valve, and an outdoor heat exchanger; a controller which controls the compressor and the electronic expansion valve; a subcooling value calculating unit which calculates a subcooling value of the refrigerant circuit; a condensing pressure detector which detects condensing pressure of the compressor; a compressor rotation number detector which detects rotation number of the compressor; and an objective subcooling value extracting unit which selects and extracting an objective subcooling value stored in advance, from the condensing pressure and the rotation number of the compressor. The controller adjusts an opening degree of the electronic expansion valve so that the calculated subcooling value of the refrigerant circuit reaches the objective subcooling value.

Abstract: A heat pump apparatus includes: a refrigerant circuit which includes a compressor, an utilization-side heat exchanger, a first expansion valve, and an outdoor heat exchanger; an injection pipe which includes a solenoid switching valve and a second expansion valve; and an objective supercooling degree table which stores objective supercooling degrees according to condensing pressure in the refrigerant circuit and rotation number of the compressor. In the heat pump apparatus, liquid refrigerant is injected to the compressor by way of the injection pipe. The heat pump apparatus switches between a first case where the liquid refrigerant is injected to the compressor and a second case where the liquid refrigerant is not injected, and a value of the objective supercooling degree is changed between the first case and the second case to control the first expansion valve based on the value of the objective supercooling degree.

Abstract: A refrigerant expansion assembly, and method of operation, for use in a vehicle air conditioning system is disclosed. An orifice channel connects an orifice inlet port to an orifice outlet port and includes a valve seat. A variable orifice assembly is mounted in the orifice channel and includes a fixed orifice passage extending axially through a variable orifice body having a sealing flange that can seal against a valve seat via an orifice spring. An orifice bypass valve includes a check ball biased against a ball seat by a bypass spring and selectively allows some of the refrigerant to bypass the variable orifice assembly. The refrigerant expansion assembly may also include a burst disk downstream of the variable orifice assembly.

Abstract: A refrigerant expansion assembly, and method of operation, for use in a vehicle air conditioning system is disclosed. The assembly has a main body including an orifice inlet port, an orifice outlet port, an orifice channel extending between the orifice inlet and outlet ports and including a fixed orifice, an upstream bypass channel extending from the orifice channel between the orifice inlet port and the fixed orifice and including a valve seat, and a downstream bypass channel extending from the orifice channel between the fixed orifice and the orifice outlet port. A bypass valve flange extends from the main body, forming a bypass chamber connected to the upstream bypass channel and the downstream bypass channel, with the ball valve seat adjacent to the bypass chamber. A check ball mounts in the bypass chamber adjacent to the valve seat, and a spring biases the check ball into the valve seat.

Abstract: The invention relates to an expansion valve and a method for controlling an expansion valve, in which the opening and closing movement of the valve-closing element is adjusted as a function of the pressure difference which is present on the high-pressure side in an inlet opening and on the low-pressure side in an outlet opening.

Abstract: Liquid refrigerant (1) is flashed-off by ultrasonic vibrations and/or diffuser plate (5) into saturated vapour that is static pressure reduced/velocity increased by the converging inlet tract and volute of turbine (4). The turbine wheel expansion cools (***) this saturated vapour—less a turbine efficiency loss heating effect and powers compressor (7). The % age free work of compressor (7) is the product of the efficiencies of turbine (4) and compressor (7). Valve (2) controls pump-down, superheat via sensors (10) & (11). Valve (16) controls hot gas bypass/turbine speed via sonic sensor (9). Compressor (13) can be any type of compressor with reduced compression and motor speed—horsepower reducing 55 to 75% plus. Exact required speed of an automobile A/C compressor is obtained via the belt drive.

Abstract: A cooling system and method are provided for facilitating two-phase heat transfer from an electronics system including a plurality of electronic devices to be cooled. The cooling system includes a plurality of evaporators coupled to the electronic devices, and a coolant loop for passing system coolant through the evaporators. The coolant loop includes a plurality of coolant branches coupled in parallel, with each coolant branch being coupled in fluid communication with a respective evaporator. The cooling system further includes a control unit for maintaining pressure of system coolant at a system coolant supply side of the coolant branches within a specific pressure range at or above saturation pressure of the system coolant for a given desired saturation temperature of system coolant into the evaporators to facilitate two-phase heat transfer in the plurality of evaporators from the electronic devices to the system coolant at the given desired saturation temperature.

Abstract: The internal heat exchanger 7 is provided which exchanges heat between the refrigerant of low pressure and the refrigerant of high pressure, and the pre-load adjusting mechanism of the expansion valve 5 is abolished. Due to the above structure, the refrigerant flowing into the expansion valve 5 is cooled in the internal heat exchanger 7, and enthalpy of the refrigerant flowing into the evaporator 6 is reduced. On the contrary, the refrigerant sucked into the compressor 1 is heated. Accordingly, a difference in enthalpy between the refrigerant at the inlet and the refrigerant at the outlet of the evaporator 6 can be made large, and the heat absorbing capacity of the evaporator 6 can be enhanced, and further it becomes possible to give the degree of superheat to the refrigerant sucked into the compressor 1. Therefore, even if the pre-load adjusting mechanism is abolished, the vapor-compression-type refrigerating machine can be stably operated.