Abstract: A subcooler is made up of a plate type heat exchanger. The accumulator is located between a compressor and the subcooler in a width direction of an outdoor unit in a planar view. The subcooler overlaps with the accumulator in the width direction in the planar view. As a result, a compact heat pump can be provided when the subcooler is a plate type heat exchanger.

Abstract: Systems and methods are presented for improving stabilization of a heating, ventilating, and air conditioning (HVAC) system. More specifically, the systems and methods include a heat-flow modulator for regulating an exchange of thermal energy between a flow of refrigerant and a sensory bulb. The exchange of thermal energy allows an expansion valve to respond to a refrigerant temperature using an actuator, which is coupled to the sensory bulb. The heat-flow modulator is formed of a body that includes a first contact surface and a second contact surface. The first contact surface is thermally-coupled to a suction line of the HVAC system, which conveys the flow of refrigerant. The second contact surface is thermally-coupled to the sensory bulb. In one instance the heat-flow modulator has variable volume depending on how installed. Other systems and methods are presented. Variable heat-flow modulators are also presented.

Abstract: A system includes a high side heat exchanger, a flash tank, a first load, a second load, a first compressor, and a heat exchanger. The flash tank is configured to store the refrigerant from the high side heat exchanger. The first load is configured to use the refrigerant from the flash tank to remove heat from a first space proximate to the first load. The second load is configured to use the refrigerant from the flash tank to remove heat from a second space proximate to the second load. The first compressor is configured to compress the refrigerant from the first load. The heat exchanger is configured to transfer heat from the refrigerant from the first compressor and the second load to the refrigerant from the high side heat exchanger, and direct the refrigerant from the first compressor and the second load to a second compressor.

Abstract: A method for controlling a refrigeration system having a compressor, heat rejecting heat exchanger, expansion valve and heat absorbing heat exchanger circulating a refrigerant in series flow, the heat absorbing heat exchanger in thermal communication with working fluid, the method includes obtaining an expansion valve position set point; using a feedback control loop to generate a controlled expansion valve position; obtaining a rate of change of an operating parameter of the system; using the rate of change of the operating parameter to generate an adjustment; modifying the controlled expansion valve position using the adjustment; and controlling the expansion valve using the modified controlled expansion valve position.

Abstract: A pressure vessel refueling system enables consistent mass flow rates and reduces the in-tank temperature rise caused by the heat of compression as gas is added to a vessel. The system includes a pressure vessel having a first gas inlet/outlet port and an interior cavity, and a nozzle is in fluid communication with the first gas inlet/outlet port. The nozzle and the pressure vessel are thermally coupled such that Joule-Thomson expansion of a gas flowing through the nozzle cools the interior cavity and contents of the pressure vessel.

Abstract: A refrigerant system includes at least one compressor (54, 56) that compresses refrigerant and delivers it downstream to a heat rejection heat exchanger (26). The heat rejection heat exchanger is a microchannel heat exchanger. Refrigerant passes from the heat rejection heat exchanger downstream to an expansion device (60), from the expansion device through an evaporator (66), and from the evaporator back to the at least one compressor. A control (58) operates at least one compressor and the expansion device to reduce pressure spikes at transient conditions.

Abstract: Embodiments are directed to receiving, by a device comprising a processor, an indication that an air conditioning unit should turn on, commanding, by the device, a valve to open a specified extent based on the received indication, and subsequent to the valve opening to the specified extent, powering-on a piece of equipment that has an impact on refrigerant flow in the air conditioning unit.

Abstract: In a method for operating an aircraft cooling system a cooling medium is guided through a cooling circuit, which is connected to a refrigerating machine and to at least one cooling station associated with a cooling energy consumer, to supply cooling medium cooled by the refrigerating to the cooling station. A temperature of the cooling medium upstream of the cooling station and a temperature of the cooling medium downstream of the cooling station are detected. The mass flow of cooling medium supplied to the cooling station is controlled in dependence on a thermal output of the cooling energy consumer and in dependence on a difference between the temperature of the cooling medium upstream of the cooling station and the temperature of the cooling medium downstream of the cooling station.

Abstract: A refrigerating and air-conditioning apparatus suppresses liquid backflow to a compressor with a simple configuration, and reduces annual power consumption. An outdoor unit and an indoor unit are connected to each other by a gas-side connecting pipe and a liquid-side connecting pipe to form a refrigerant circuit in which a compressor, a four-way valve, an indoor heat exchanger, a refrigerant heat exchanger, an expansion valve, an outdoor heat exchanger, and an accumulator are sequentially connected. The refrigerant heat exchanger transfers heat between a high-pressure-side refrigerant flowing between the expansion valve and an outdoor-unit liquid pipe connecting portion and a low-pressure-side refrigerant on an outlet side of the accumulator.

Abstract: A cryopump system includes a cryopump configured to perform a preparatory operation including a cooldown from a room temperature to a cryogenic temperature and to perform a vacuum pumping operation at the cryogenic temperature, a compressor unit of a working gas for the cryopump, a gas line connecting the cryopump and the compressor unit, a gas volume adjuster configured to increase a quantity of the working gas in the gas line during the vacuum pumping operation in comparison with that during the preparatory operation, and a control device configured to control the compressor unit so as to provide a pressure control for the gas line.

Abstract: An air-conditioning apparatus including a check valve in a passage between a first flow switching device and a suction side of a compressor, an expansion valve midway of a liquid extension piping, and an additional unit having a first bypass and a second bypass that are branched off from a passage between an indoor unit and the liquid expansion valve, and are connected to a passage between the check valve and the suction side of the compressor. The first bypass has, midway thereof, a first bypass expansion valve capable of controlling a throughput of refrigerant and an auxiliary heat exchanger that has a heat source different from the refrigerant, the auxiliary heat exchanger functioning as an evaporator heating the refrigerant flowing in the first bypass. The second bypass has, midway thereof, a second bypass expansion valve capable of controlling a throughput of refrigerant.

Abstract: An air-conditioning apparatus includes a time constant calculation unit that estimates a response time constant at a time when an opening degree of an expansion device is changed on the basis of specifications of a compressor that forms a refrigeration cycle of the air-conditioning apparatus, specifications of a load side heat exchanger, and an operating state quantity of the air-conditioning apparatus, a control constant calculation means that calculates at least one of a control gain of the opening degree of the expansion device and a control interval on the basis of a calculation result of the time constant calculation means, and a control constant change means that changes a control constant.

Abstract: A refrigeration system including a condenser having a condenser inlet and a condenser outlet, a compressor fluidly connected to the condenser inlet, and an evaporator including an evaporator inlet and an evaporator outlet. The evaporator outlet is fluidly connected to the compressor. A compressor speed sensor senses an operational speed of the compressor. An electric expansion valve (EEV) is fluidly connected to the condenser outlet and the evaporator inlet. The EEV includes a valve member that is selectively positioned to establish a desired opening to pass refrigerant from the condenser to the evaporator. A controller is electrically connected to the EEV and the compressor speed sensor. The controller establishes the desired opening of the valve member based on one of a cooling mode superheat value and a heating mode super heat value, and the operational speed of the compressor.

Abstract: A method of reducing a cyclical loss coefficient of an HVAC system efficiency rating of an HVAC system includes operating the HVAC system using a recorded electronic expansion valve position of an electronic expansion valve of the HVAC system, discontinuing operation of the HVAC system, and resuming operation of the HVAC system using an electronic expansion valve position that allows greater refrigerant mass flow through the expansion valve as compared to the recorded electronic expansion valve position.

Abstract: A time for loading a refrigerant is shortened when a utilization unit of an air conditioner is installed. A heat source unit 1 includes a compressor 100; a heat-source-side heat exchanger 200; a refrigerant regulator 61 storing a refrigerant; an introducing pipe 62 which is a pipe that is branched off from a discharge-side pipe 110 of the compressor 100 and connected to the refrigerant regulator 61, and introduces the refrigerant discharged from the compressor 100 into the refrigerant regulator 61; and a lead-out pipe 63 which is a pipe that is connected from the refrigerant regulator 61 to an intake-side pipe 120 of the compressor 100, and leads out the refrigerant stored in the refrigerant regulator 61 into the intake-side pipe 120.

Abstract: A refrigeration apparatus includes a condensing unit, a flow distributor, and an evaporator connected to the condensing unit via the flow distributor. A pressure detector is configured to detect condensation pressure of the refrigerant. A calculation unit is configured to calculate a target condensation pressure of refrigerant necessary for the refrigerant to be an evaporation temperature in the evaporator. A controller is configured to control the condensing unit so that the condensation pressure of the refrigerant becomes equal to or more than the target condensation pressure.

Abstract: An expansion valve is disclosed herein and includes a valve body having a chamber; a valve seat and a valve core are provided in the chamber; a first opening and a second opening in communication with the chamber, wherein the valve core moves relative to the valve seat to control a size of a flow channel between the first opening and the second opening, wherein the valve core includes a valve core head portion facing the valve seat, the valve head portion is provided with an axial through hole, a piston is provided in the axial through hole, the piston is connected with the valve body. The piston which is connected with the valve body is provided in the axial through hole of the valve core head portion of the expansion valve.

Abstract: An electrically controlled expansion valve package (10) comprises an expansion valve (30), sensors (32, 33, 36) and control electronics (35) all included in a monolithic package that greatly simplifies installation, while also enabling performance enhancements. The expansion valve is controlled by control electronics that, among other things, determines from pressure and temperature sensors the type or nature of the refrigerant being used in the refrigeration system for adapting control of the expansion valve to the refrigerant.

Abstract: A refrigeration device includes a compression mechanism, a radiator, a first expansion mechanism, a liquid receiver, a second expansion mechanism, an evaporator, a pressure detector, a temperature detector, and a control unit. The pressure detector is provided between the refrigerant discharge side of the compression mechanism and the refrigerant inflow side of the first expansion mechanism. The temperature detector is provided between the exit side of the radiator and the refrigerant inflow side of the first expansion mechanism. The control unit controls the first expansion mechanism using the pressure detected by the pressure detector and the temperature detected by the temperature detector so that the refrigerant flowing out from the first expansion mechanism reaches a saturated state.

Abstract: An air conditioner is provided. The air conditioner includes a first temperature sensor configured to measure an indoor temperature during a heating operation, a second temperature sensor configured to measure a discharge temperature of a compressor, a valve provided at an outlet side of an indoor heat exchanger during the heating operation, and a controller configured to control an opening of the valve by comparing a temperature detected by the first temperature sensor with a temperature detected by the second temperature sensor.

Abstract: After a chiller unit is started, an opening command of 10 pulses is output to an electronic expansion valve, and after a predetermined period of time (at the time of starting with unload) elapses, an opening command of 100 to 150 pulses is output to open the electronic expansion valve up to a predetermined opening degree. Thereafter, a discharge side refrigerant super-heat TdSH is monitored and a closing command of 1 pulse/sec is output to the electronic expansion valve to drive the same in a closing direction in a short time until TdSH becomes 20 K. After TdSH has reached 20 K, a closing command of 1 pulse/3 sec is output to the electronic expansion valve, until TdSH becomes 25 K, to drive the electronic expansion valve 3 at a smaller speed in the closing direction than that speed in the closing direction until TdSH becomes 20 K.

Abstract: A refrigeration device includes a compression mechanism, a radiator, a first expansion mechanism (15), a liquid receiver (16), a second expansion mechanism, an evaporator, a temperature detector, a first pressure storing unit (23a), and a second pressure determining unit, a pressure detector, and a control unit (23c). The first pressure storing unit stores an upper limit and lower limit of an intermediate pressure. The second pressure determining unit determines an upper limit and lower limit of a high pressure based on the upper limit and lower limit of the intermediate pressure and on a temperature in a vicinity of an exit of the radiator. The control unit controls the first expansion mechanism and the second expansion mechanism so that a pressure detected by the pressure detector will be equal to or less than the upper limit and equal to or greater than the lower limit of the high pressure.

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: 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 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: 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: Vapor compression air conditioning systems are provided with a flow restrictor for transferring working fluid to and from at least one of the compressor low pressure inlet conduit and compressor high pressure outlet conduit to provide for accurate charge adjustment to achieve predetermined fluid sub-cooling. Pressure and temperature measurements are taken at a condenser fluid outlet conduit and provided to a microcontroller for determining fluid sub-cooling and comparing sub-cooling with a predetermined target sub-cooling. A charge addition or recovery apparatus may include a solenoid valve controlled by the microcontroller to more accurately control the addition or recovery of refrigerant fluid charge.

Abstract: A refrigeration apparatus includes a condensing unit, a flow distributor, and an evaporator connected to the condensing unit via the flow distributor. A pressure detector is configured to detect condensation pressure of the refrigerant. A calculation unit is configured to calculate a target condensation pressure of refrigerant necessary for the refrigerant to be an evaporation temperature in the evaporator. A controller is configured to control the condensing unit so that the condensation pressure of the refrigerant becomes equal to or more than the target condensation pressure.

Abstract: A multi type air-conditioner is provided. The multi type air conditioner includes an outdoor unit having a plurality of outdoor heat exchangers that heat-exchanges with outdoor air and a compressor that compresses a refrigerant; a plurality of indoor units that performs either cooling or heating; a high pressure pipe connected between a discharge side of the compressor and the plurality of indoor units; a low pressure pipe connected between a suction side of the compressor and the plurality of indoor units; and a refrigerant exhauster provided between the high pressure pipe and the low pressure pipe. The refrigerant exhauster discharges a liquid refrigerant to the low pressure pipe when the liquid refrigerant is accumulated in the high pressure pipe, whereby degradation of cooling capability due to a lack of refrigerant may be prevented by minimizing accumulation of the liquid refrigerant in the high pressure pipe in a cooling operation mode.

Abstract: An air cargo container temperature control system and method utilizing multiple refrigeration circuits and a controller that activates one or more of the refrigeration circuits in various modes to maintain temperature control. Each of the refrigeration circuits comprises a compressor, a condenser, and an evaporator all in fluid communication to form each refrigeration circuit. Additionally, heating elements are positioned in an evaporator cell for heating load space air and/or defrosting evaporator coils. The system is also provided with a battery pack having a transformer and battery chargers for charging corresponding battery cells by transforming power from an external source. The method compares a measured temperature to a set point temperature and activates one or more refrigeration circuits depending on the temperature difference.

Abstract: In a refrigeration cycle apparatus having an expansion mechanism, a method to swiftly generate a pressure difference upstream and downstream of the expansion mechanism of, thereby enhancing the starting performance of the refrigeration cycle apparatus The apparatus has a compression mechanism, a utilizing-side heat exchange, an expansion mechanism for recovering power, and a heat source-side heat exchanger. The revolution number of the heat source fluid transfer means is made smaller than a target revolution number or the heat source fluid transfer means is stopped during a predetermined time after the compression mechanism is started. When the compression mechanism is started, the pressure difference can be generated upstream and downstream of the expansion mechanism for a short time, the operation of the expansion mechanism does not become unstable, vibration and noise can be prevented, and the refrigeration cycle apparatus can swiftly be started.

Abstract: An auger type ice making machine is provided with a freezing cylinder into which water for making ice is supplied, an ice-scraping auger for scraping ice formed on the inner surface of the freezing cylinder, and an auger motor for driving the ice-scraping auger. A freezing apparatus has a compressor driven by a motor, circulating refrigerant discharged from the compressor through a condenser, a dryer, a constant pressure expansion valve, and an evaporator provided on the outer peripheral surface of the freezing cylinder. At the outlet of the evaporator there is provided a temperature sensor for sensing refrigerant temperature. A controller controls the rotational speed of the motor through an inverter circuit such that the sensed refrigerant temperature is equal to a specified refrigerant temperature, allowing the freezing apparatus to keep ice-making performance thereof.

Abstract: A control device for an air-conditioning system of a vehicle comprises an evaporator, a compressor with externally controlled variable displacement, and an expansion valve. The control device comprises a control block that receives a reference temperature indicating a desired temperature of the air downstream of the evaporator, and an effective temperature of the air present downstream of the evaporator. The control device-supplies a control signal for the compressor to bring the effective temperature substantially equal to the reference temperature. An observer module receives the control signal and supplies a temperature disturbance indicating an estimate of the oscillatory effect generated by an expansion valve on the temperature of air downstream of the evaporator when a compressor is driven by the control signal. An adder block removes from the effective temperature the temperature disturbance so as to eliminate the oscillatory effect on the effective temperature downstream of the evaporator.

Abstract: The invention relates to a control unit for controlling the expansion valve of a refrigeration or air conditioning system, comprising a temperature sensor that is connected upstream of the expansion valve in the coolant circuit. If the control unit detects a decrease in temperature of the aforementioned temperature sensor, which is generally caused by the start of a defrosting process, it displaces the expansion valve into a static state, to protect said valve during the defrosting process.

Abstract: The invention relates to an evaporator control by use of an expansion valve and an internal heat exchanger IHE. The evaporator control is controlled after the start of the evaporation process and the temperature of the compressor suction vapor, oil and hot gas as well as coolant liquid is controlled and regulated upstream of the expansion valve.

Abstract: A refrigeration device includes a compression mechanism, a radiator, a first expansion mechanism, a liquid receiver, a second expansion mechanism, an evaporator, a pressure detector, a temperature detector, and a control unit. The pressure detector is provided between the refrigerant discharge side of the compression mechanism and the refrigerant inflow side of the first expansion mechanism. The temperature detector is provided between the exit side of the radiator and the refrigerant inflow side of the first expansion mechanism. The control unit controls the first expansion mechanism using the pressure detected by the pressure detector and the temperature detected by the temperature detector so that the refrigerant flowing out from the first expansion mechanism reaches a saturated state.

Abstract: A heat transfer system capable of being coupled to at least one temperature controlled zone, the elements of the system comprising: (i) at least one liquid refrigerant line; (ii) at least one expansion valve selected for R22 or R422D; (iii) at least one evaporator (iv) at least one compressor; (v) at least one condenser; (vi) at least one vapor refrigerant line; and wherein all of the elements have an inlet side and an outlet side and elements (i) through (vi) are in fluid communication together and contains R422D; and the system further comprising a sensing element communicatively coupled to the outlet side of at least one evaporator and at least one expansion valve and at least one sensing element contains a fluid selected to work when R22 is in the condenser-to-evaporator circuit, or R422D. Further disclosed are methods for retrofitting R22 containing heat transfer systems, including refrigerators and air conditioners. Also disclosed are refrigerators and air conditioners containing only R422D.

Abstract: A refrigeration apparatus (10) includes: a valve control means (33) configured to control the opening of an expansion valve (13); and opening degree detection means (32, 34) configured to perform, after a pump-down operation in which a compressor (11) is driven with the expansion valve (13) closed, an opening degree detection operation of detecting an opening degree that is an opening command value for use in changing the expansion valve (13) from a closed state to an open state, by determining whether the expansion valve (13) is open based on a change in state of low-pressure refrigerant between the expansion valve (13) and the suction side of the compressor (11), while gradually increasing the opening command value output to the expansion valve (13) with the compressor (11) deactivated. The valve control means (33) controls the expansion valve (13) using the opening degree detected in the opening degree detection operation.

Abstract: Disclosed herein is a method of controlling a linear expansion valve of a cooling cycle apparatus. The method comprises a first step of calculating a target opening level value according to suction overheat level of compressors to control a linear expansion valve based on the calculated target opening level value, and a second step of calculating a new target opening level value according to the suction overheat level of the compressors and discharge temperature of the compressors to control the linear expansion valve based on the calculated new target opening level value. Consequently, the discharge temperature of the compressors is prevented from being excessively increased, and therefore, the compressors are prevented from being overheated and damaged, and reliability of the cooling cycle apparatus is improved.

Abstract: A high-pressure side discharge port of a two-stage compressor (12A) and a condenser (14A) are connected, condenser (14A) and a PMV (15A) are connected, a refrigerating side exit of PMV (15A) is connected to a medium pressure side suction port of two-stage compressor (12A) via an R capillary tube (16A) and an F evaporator (18A), connected to an F evaporator (26A) via an F capillary tube (24A), F evaporator (26A) is connected to a low-pressure side suction port of two-stage compressor (12A) via a low-pressure suction pipe (28A), PMV (15A) can switch a simultaneous cooling mode and a freezing mode, and in the simultaneous cooling mode, a refrigerant flow rate toward R evaporator (18A) is adjusted by PMV (15A), and thereby a temperature difference control is performed so as to make a difference between an entrance temperature and an exit temperature of R evaporator (18A) equal to a preset temperature difference (for example, 4° C.).

Abstract: An apparatus and method for compressing gas refrigerant using two different compressors operated alternatively in a series or parallel mode for obtaining two different compression ratios and thereby provide efficient operation for both a relatively lower suction pressure and a relatively higher suction pressure. This system avoids an unbalanced mass flow rate when the compressors are operated in series by unloading a downstream one of the compressors. When operated in the series mode, refrigerant is bypassed back to a suction inlet of the downstream compressor during a portion of a compression stroke of the downstream compressor for equalizing the mass flow rate through the two compressors.

Abstract: A refrigeration system for use with a plurality of temperature controlled cases is disclosed. The refrigeration system includes a cooling system having at least one compressor and a condenser for supplying liquid refrigerant to a cooling element associated with each case. Each cooling element receives liquid refrigerant through a liquid refrigerant supply line and returns vapor refrigerant through a suction line. The refrigeration system further includes a control module having a stored reference temperature (T ref) for each case, a temperature sensor disposed in each case for generating a signal representative of the actual temperature within the case (T act), and an expansion device provided at the liquid refrigerant supply line side of each case. The control module compares T ref with T act and moves the expansion devices between an open position and a closed position accordingly to obtain or maintain the desired temperature in each temperature controlled case.

Abstract: A refrigerant cycle is provided with a control for an expansion device to achieve a desired compressor discharge pressure. The system operates transcritically, such that greater freedom over compressor discharge pressure is provided. The system's efficiency is optimized by selecting an optimum discharge pressure. The optimum discharge pressure is selected based upon sensed environmental conditions, and the expansion device is adjusted to achieve the desired compressor discharge pressure. A feedback loop may be provided to sense the actual compressor discharge pressure and adjust the actual compressor discharge pressure by further refining the expansion device. The system is disclosed providing heated water based upon a demand for a particular hot water temperature.

Abstract: The invention relates to a thermostatic expansion valve having a valve element (33) which, for the throughflow of the refrigerant, closes and moves in the opening direction a valve seat (32) of a passage opening (29) arranged between the supply opening (27) and the discharge opening (31), and which is assigned to a first actuating element (36), the first actuating element (36) comprising a chamber (38) which is delimited with a first active face (37) and which contains a control charge (41), wherein an actuating element (46) is provided, which is thermally activated independently of the high pressure, the actuating movement of which actuating element (46) is coupled in terms of movement to the first active face (37) of the first actuating element (36) when a temperature-dependent actuating movement of the thermally activatable actuating element (46) acts counter to the actuating movement of the first active face (37) of the first actuating element (36), with a temperature threshold value of the thermally acti

Abstract: A system and method for maintaining the temperature of a thermal transfer fluid at a selectable level within a wide temperature range, so as to operate a process tool in a chosen mode employing at lease two cascaded stages, each operating with a different fluid in a separate refrigeration cycle. By interrelating energy transfers between parts of upper and lower stages, thermal efficiency is maximized and a smooth continuum of temperature levels can be provided. The refrigerants advantageously have vaporization points below and above ambient, for upper and lower stages respectively, and employs the upper stage for a constant refrigeration capacity, controlling the final temperature with the lower stage. The system allows for a further extension of range because the thermal transfer fluid can be heated for some process tool modes as the refrigeration cycles are run at low loads.

Abstract: An expansion valve has a solenoid relief valve equipped in an air conditioner for decompressing and expands a refrigerant and supplies the same to an evaporator. A high-pressure refrigerant from a compressor enters a valve chamber. The refrigerant traveling towards the evaporator flows through a first passage. The refrigerant returning from the evaporator toward the compressor flows through a second passage. A valve seat is disposed between the valve chamber and the first passage. A valve body has a refrigerant chamber disposed in parallel to the valve seat and communicates the valve chamber and the first passage. A valve device is capable of coming into contact with and separating from the valve seat. A power element drives the valve device. A solenoid relief valve is disposed between the refrigerant chamber and the first passage.

Abstract: A cooling apparatus (10) for cooling a detector (52), the cooling apparatus including an inner and an outer countercurrent heat exchanger (12 and 14, respectively) for a first and a second gas in a thermally insulating housing (16), the inner countercurrent heat exchanger (12) being arranged within a sublength of the outer countercurrent heat exchanger (14), and the inner countercurrent heat exchanger (12) being spatially separated from the outer countercurrent heat exchanger (14) by an outer sleeve (18). In this apparatus, the outer sleeve (18) has a partition plate (32) between an expansion nozzle (28) for the first gas located at the end of the inner countercurrent heat exchanger (12) and the remaining part of the outer countercurrent heat exchanger (14).

Abstract: A method and apparatus for refrigeration system control includes a control system operable to meet cooling demand and control suction pressure for a plurality of refrigeration circuits each including a variable valve and an expansion valve. The controller controls the variable valve independently of the expansion valves to meet cooling demand by determining a change in a measured parameter and controlling at least one of the variable valves based upon the change to an approximately fully open position.

Abstract: Disclosed are an apparatus and a method for controlling the operation of an air conditioner, in which one or more compressors are operated so that the total refrigerant compression capacity of the operating compressors is variably changed according to a cooling or heating load to be eliminated, and an opening degree of an electronic expansion valve is controlled between minimum and maximum values set according to the total refrigerant compression capacity of the operating compressors, thus stably operating the air conditioner and preventing the refrigerant in a liquid state from being introduced into the compressors and the compressors from overheating.

Abstract: An expansion valve unit having a pressure detecting function includes a supercooling control expansion valve disposed in a flow path of a refrigerant sent into an evaporator of a refrigeration system constituting a refrigerating cycle to control the flow rate of the refrigerant. A pressure detector is provided at one end of the supercooling control expansion valve to detect the pressure of the refrigerant sent thereto through a passage in the expansion valve. The supercooling control expansion valve and the pressure detector are integrated with each other by a joining means.