Abstract: A refrigeration system to be driven by an electrical power source. A compressor mechanism in a hermetically sealed compressor housing circulates a refrigerant located within the compressor housing through a loop. A motor in the compressor housing and in contact with the refrigerant within the compressor housing is coupled with the compressor mechanism. A power supply line adapted to be connected to the electrical power source has an interior portion passing through and located within the compressor housing. The interior portion is in contact with the refrigerant in the compressor housing. A power switching circuit in the compressor housing and in contact with the refrigerant within the compressor housing connects between the power supply line and the winding for selectively applying electrical power from the electrical power source to a motor winding.

Abstract: In a preferred embodiment, a single motor drives both oil and refrigerant pumps in a refrigeration chiller, the motor and oil pump being disposed in the chiller's oil supply tank and the refrigerant pump being disposed exterior thereof. The refrigerant pump pumps liquid refrigerant to the chiller's compressor section so as to cool the motor by which the compressor is driven while the oil pump pumps oil to chiller locations that require lubrication when the chiller is in operation. A uniquely designed impeller permits low pressure liquid refrigerant in its liquid state to be reliably pumped to a location of use, without significant flashing, from a source location which is at a height only a short distance above the pump inlet. A stand alone refrigerant pump embodiment is also described.

Abstract: A liquid injection type scroll compressor is used to a refrigerating apparatus using hydrocarbon fluoride refrigerant which does not contain chlorine (HFC-125/HFC-143a/HFC-134a) as an operating fluid and an amount of an injected liquid is controlled according to a discharge temperature of the compressor. Further, ester oil and/or ether oil is used as refrigerator oil and a dryer is disposed in a refrigerating cycle. With this arrangement, a refrigerating cycle operation can be stably realized in a wide range without almost changing the arrangement of a conventional refrigerating apparatus.

Abstract: A refrigerating system has a condenser, an evaporator, and a two-stage centrifugal compressor assembly with an electric motor provided with a cooling system. A condenser inlet is connected to a compressor assembly outlet, while a condenser outlet is connected via first and second choke elements to an inlet of the evaporator and to the cooling system. The evaporator outlet communicates with the compressor assembly inlet, and the cooling system outlet communicates with the inlet of the second stage of the assembly. The cooling system is provide with a cooling skirt having a cavity of the cooling system lying between a stator and a housing. The refrigerating system has a separator vessel, a recuperative heat exchanger, and a heat-regulating valve controlled by the coolant pressure and temperature at the cooling skirt inlet, and also fitted in series with the separator vessel in the line connecting the condenser inlet to the evaporator. The separator vessel is connected by a gas phase to the coolant feed duct.

Abstract: An enhanced motor cooling and lubrication system for a liquid chiller includes a liquid refrigerant cooled compressor drive motor, wherein the refrigerant used to cool the drive motor is returned to the chiller's condenser, and apparatus to better facilitate the return of oil carried to the compressor entrained in the suction gas flow stream back to the chiller's oil supply tank.

Abstract: In a refrigerant cycle having a gas refrigerant bypass passage through which high-temperature gas refrigerant is introduced from a compressor into an evaporator while bypassing a condenser, a super-heating degree of gas refrigerant discharged from the compressor is determined according to signals from a pressure sensor and a temperature sensor disposed at a refrigerant discharging side of the compressor. According to the super-heating degree of gas refrigerant discharged from the compressor, refrigerant staying in the condenser is controlled so that refrigerant amount circulating in the refrigerant cycle is suitably controlled. Thus, heating capacity of the refrigerant cycle using the gas refrigerant bypass passage is improved, while the compressor is protected.

Abstract: Apparatus for delivering a cryogenic liquid comprising a thermally insulated main pipe in which a device for throttling a flow of liquid is mounted, a degassing pipe which is tapped off the upper part of the main pipe downstream of the throttling device.

Abstract: The invention concerns a hermetic cooling compressor with an electric motor having a variable speed controlled by a converter cooled by a cooling medium flow. The compressor and the converter are formed together as a unit, in which a medium flowing through the unit is used for cooling of the electronic circuit of the converter. Thus the electronic circuit can be made without bulky cooling plates.

Abstract: Responsive to a request for refrigeration, a start up sequence is initiated and, if start up is achieved, a number of motor and compressor parameters of operation are sensed for controlling and protecting the compressor. Depending upon the nature of the sensed conditions, if necessary, the motor, and thereby the compressor, is either disabled or corrective action is initially taken to bring the parameters within an acceptable range. If corrective action is ineffective, the motor and thereby the compressor, is disabled.

Abstract: A vapor compression system in which a quantity of a refrigerant circulates between at least two pressure levels in a condenser and an evaporator respectively, comprises a compressor (1) for increasing the pressure of refrigerant vapor; a condenser (5) for high pressure refrigerant vapor received from the compressor; an expansion device (13) such as a valve across which the pressure differential between the condenser and the evaporator is maintained, to control the withdrawal of liquid refrigerant from the condenser according to the volume of liquid refrigerant that is within or behind it; an evaporator (15) for liquid refrigerant received from the condenser; a receiver (21) into which refrigerant is discharged from the evaporator, with a vapor withdrawal conduit (25) through which vapor is withdrawn from the receiver for supply to the compressor, the receiver including a reservoir (23) into which liquid refrigerant discharged from the evaporator collects, to control supply of liquid refrigerant to the compres

Abstract: The expanded flow through a heat exchanger type economizer is controlled by an electronic expansion valve and is supplied to the motor of a motor compressor to cool the motor. The electronic expansion valve is controlled by a microprocessor responsive to the temperature of the motor winding sensed by a thermistor.

Abstract: A motor cooling structure for a turbo compressor is disclosed. The structure includes a refrigerant suction tube communicating with one lateral wall of the sealed container and extended from the evaporator, a first refrigerant flow tube communicating with another lateral wall of the sealed container, with the first refrigerant flow tube communicating with the first compression chamber, a second refrigerant flow tube through which the first compression chamber communicates with the second compression chamber, and a refrigerant discharge tube communicating with the second compression chamber communicating with a condenser, for thereby enhancing a cooling efficiency of the driving motor by directly introducing a low temperature refrigerant from an evaporator into a motor chamber.

Abstract: In a refrigerating apparatus using an HFC group refrigerant, the performance is improved by increasing the refrigerating capacity and a stable operation is made possible. In order to achieve this, a cycle system in a refrigerator is structured so as to connect a compressor, a condenser, a liquid receiver and a supercooler in this order. In an air-cooled separation type refrigerator, the liquid receiver is disposed within an air-cooled type condenser unit. Further, in the case where a flush gas is liable to be generated in a liquid pipe, a vapor-liquid separator is disposed within the compressor unit integral with an accumulator and separated therefrom by a partition plate.

Abstract: An air conditioner increases a flow rate of a refrigerant to be sucked to a compressor so that a superheat of the refrigerant is reduced when a coil temperature of a driving motor for a compressor is more than a predetermined temperature.

Abstract: A self-contained refrigeration system utilizes a solenoid valve to meter refrigerant to a thermal process, the thermal process to be maintained at a predetermined temperature. When cooling of the thermal process is not required, refrigerant is recycled without coming into thermal contact with the thermal process by way of a hot gas bypass valve.

Abstract: A liquid injection type scroll compressor is used to a refrigerating apparatus using hydrocarbon fluoride refrigerant which does not contain chlorine (HFC-125/HFC-143a/HFC-134a) as an operating fluid and an amount of an injected liquid is controlled according to a discharge temperature of the compressor. Further, ester oil and/or ether oil is used as refrigerator oil and a dryer is disposed in a refrigerating cycle. With this arrangement, a refrigerating cycle operation can be stably realized in a wide range without almost changing the arrangement of a conventional refrigerating apparatus.

Abstract: The present invention provides a method and system for controlling and limiting the discharge temperature of a compressor of a refrigeration system. The invention is suitable for converting an existing refrigeration system which operates with one refrigerant to use with another refrigerant which can cause high discharge temperatures. The invention includes a simple four-part system-a temperature sensor to sense the discharge temperature, an injection valve for injecting liquid refrigerant into the suction gas line of the compressor, a fluid line for providing liquid refrigerant to the valve from the condenser and a digital controller for actuating the valve.

Abstract: A high pressure gas compressor in one embodiment having an internal two staged compression with a compression chamber formed in part by a positive displacement, stepped piston and cylinder configuration, providing a first stage compression by an enlarged diameter segment of the piston and a second stage compression provided by a smaller diameter segment of the piston, and in another embodiment having an internal, single stage compression with a high compression ratio.

Abstract: A cooling probe device for cooling oil in a refrigerating compressor is described. It comprises a housing having a coupling for connecting same to a connecting bore of a sealed oil casing of a refrigerating compressor with the housing supported exteriorly of the casing. A pair of refrigerant conduits extend through a chamber of the housing and exit through the coupling a predetermined distance and terminate in a probe to feed a refrigerant gas to the probe through a first of the conduits and out of the probe through a second of the conduits. The predetermined distance of the conduits constitutes a bendable support connection to position the probe immersed in oil contained in the sealed oil casing. The conduits are sealingly connected to the chamber of the housing.

Abstract: The invention relates to systems and methods for delivering controlled doses of a liquid cryogen. Controlling a restriction in a return conduit and other system geometry maintains proper circulation through a delivery and return conduit, enabling reliable control over the temperature and pressure of the liquid cryogen at the site of dosing.

Abstract: A scroll compressor having injection ports 70A and 70B opened to operating chambers Vc during a predetermined period of a complete compression cycle, so that a part of the refrigerant circulating in a refrigerating system is injected into the compression chambers from the injection ports. The injection ports are opened to an intermediate pressure chamber, which is at a pressure between the pressure of the refrigerant sucked into the compressor and the pressure of the refrigerant discharged from the compressor. The intermediate pressure chamber is arranged so as to eliminate pressure pulsations therein. Check valves 72A and 72B are provided in an end plate 54 of a stationary scroll member 50. Furthermore, relief valves may also be provided in the end plate for releasing the pressure of the operating chambers to a low pressure side of the refrigerating system.

Abstract: A high pressure gas compressor having an internal two staged compression with a compression chamber formed in part by a positive displacement, stepped piston and cylinder configuration, providing a first stage compression by an enlarged diameter segment of the piston and a second stage compression provided by a smaller diameter segment of the piston. Temperature is maintained within design limits by the admission to the compression chamber of an expanded gas from a high pressure storage, which on adiabatic expansion of the admission gas reduces the temperature of the mixed charge for final compression at a resultant temperature that is within the design limits of the compressor unit.

Abstract: A refrigeration system which has in a closed loop a compressor body, with a cooling jacket, for compressing a refrigerant, a condenser for condensing the compressed refrigerant to a liquid refrigerant, and a condensed liquid pump for compressor body cooling. The compressor body is thermally coupled to a cooling jacket, through which a cooling liquid flows. The condensed liquid pump pumps condensed liquid refrigerant from the condenser through the cooling jacket, cooling the compressor body, and then to the compressor cylinder head exhaust manifold, where the liquid refrigerant mixes with and cools the hot compressor discharge gas.

Abstract: A flash tank economizer containing a first expansion device to expand high pressure refrigerant from a system condenser to an intermediate pressure and a second expansion device for further expanding liquid refrigerant at the intermediate pressure that has collected in the tank to a desired low pressure for delivery to the system evaporator. Vapor phase refrigerant produced by the first expansion in the tank is injected back into the system compressor at the intermediate pressure.

Abstract: A high pressure gas compressor in one embodiment having an internal two staged compression with a compression chamber formed in part by a positive displacement, stepped piston and cylinder configuration, providing a first stage compression by an enlarged diameter segment of the piston and a second stage compression provided by a smaller diameter segment of the piston, and in another embodiment having an internal, single stage compression with a high compression ratio.

Abstract: A refrigerating unit comprising an adiabatic box provided with a door to its opening, a machine compartment in contact with said adiabatic box, and a refrigerating cycle wherein the machine compartment is covered with a damping plate and is attached to the adiabatic box with a jointing means so as to be sealed, and further said refrigerating unit comprises an oil cooler for cooling lubricating oil in a compressor in the refrigerating cycle is provided. By this, noise and vibration generated by a refrigerator itself such as noise generated by a flowing or boiling refrigerant in the compressor and an evaporator can be effectively removed, noise and vibration generated by resonance between vibration by a refrigerator and a wall or a cabinet can be attenuated and the effect of heat release can be enhanced.

Abstract: A refrigerating system for air-conditioning an air-conditioned area, and incorporating therein a variable capacity refrigerant compressor in which the delivery amount of the compressed refrigerant is varied by changing the stroke of the reciprocating pistons which are operatively connected to a swash plate mechanism by changing its angle of inclination in response to a change in the pressure in a crank chamber, a condenser for condensing the compressed gas-phase refrigerant from the compressor, a pressure reducing unit for reducing the pressure of the liquid-phase refrigerant, an evaporator for vaporizing the liquid-phase refrigerant by removing heat from the air, around the evaporator, which cools the air-conditioned area, and a refrigerant supply conduit supplying the crank chamber of the compressor with a part of the liquid-phase refrigerant flowing in a portion of the refrigerant conduit extending from the condenser to the evaporator so that during the minimum capacity operation of the compressor, the com

Abstract: A scroll compressor includes a liquid injection system. The liquid injection system receives liquid refrigerant from the refrigeration system at a point between the condenser and the evaporator. This liquid refrigerant is then injected into at least one enclosed space defined by the scrolls of the scroll compressor. The liquid injection system includes a valve which selectively controls the flow of liquid refrigerant to the enclosed space. The valve is responsive to the discharge pressure of the compressor.

Abstract: An improved commingling chamber for the distribution and pressure equalization of a thermodynamic working fluid used in a recirculating liquid type heat transfer processing system. The improved commingling chamber includes a volumetric chamber generally defined by a vessel wall, a top portion of the chamber, a lower portion of the chamber having a side wall. The lower portion terminates into a base preferably having an outlet port located therein. At least one inlet port and outlet port are located in the vessel wall. A conduit having a first end attached to at least one inlet port and being of sufficient length and configuration to vector incoming fluid toward the base outlet port, and a flow through region between a terminating end of the conduit means is provided to form a flow path between fluid exiting the conduit and the volumetric chamber. Alternative embodiments for accommodating multiple inlet ports and outlet ports are disclosed.

Abstract: Application of a positive displacement pump to the pumping of helium at very low temperatures. Positive displacement pumps, formed from mobile components (35, 36), which deliver gas volumes to pumping chambers, have the advantage of operating under satisfactory conditions for significant temperature, pressure and gas flow rate variations. They are therefore preferred as compared with the hitherto used centrifugal pumps and have means enabling them to operate at very low temperatures.

Abstract: In a refrigeration system having low and high stage compressors and a subcooler or economizer, economizer gas is selectively supplied to the compressor motors for cooling and to the suction of the high stage to increase capacity. By selectively controlling the delivery of the economizer gas, efficiency of the refrigeration system is increased.

Abstract: A cryogen delivery apparatus for delivering cryogen in a saturated state includes a vessel to contain the cryogen in liquid and vapor phases. The vessel has a headspace region and a heat exchanger located within the headspace region for indirectly exchanging heat between the vapor located within the headspace region and a liquid stream composed of the liquid phase of the cryogen. In case the cryogen is introduced into the vessel as a subcooled liquid, the vapor will condense into the liquid phase and the subcooled liquid will be converted into a saturated liquid. The saturated liquid will then be discharged from a liquid outlet connected to the heat exchanger. In the event the liquid enters the vessel as two-phase flow, the vessel will act as a phase separator. A branched supply line is provided having a liquid inlet branch connected to a bottom liquid inlet of the vessel so that a supply stream composed of the cryogen flows into the vessel.

Abstract: According to the present invention, a piping installation for supplying a low temperature fluid such as liquid nitrogen from a main pipe (17) of transporting the low temperature fluid to predetermined equipments (2, 4, 6), for example a cooling apparatus, by way of branch pipes (18, 19), is characterized in that a thermally insulated pipe having a small outer diameter is used for the branch pipes (18, 19). By reducing the diameter of the branch pipes (18, 19) of the piping installation, the occupation of them in a space can be reduced, whereby spaces (3, 5) where they are installed can be effectively utilized. By reducing the diameter of the branch pipes (18, 19), furthermore, the quantity of the low temperature fluid which has been hitherto discharged wastefully can be decreased.

Abstract: A refrigerator comprises a compressor for compressing and discharging a coolant, a first heat exchanger which performs heat exchange between the compressed coolant from the compressor and the atmosphere to cool the compressed coolant, an adiabatic expansion orifice where the compressed and cooled coolant after passing the first heat exchanger is adiabatically expanded, and a second heat exchanger which performs heat exchange between the adiabatically expanded coolant and the air in refrigerating chambers so as to cool the air in the refrigerating chambers by the coolant and to heat the coolant by the air in the refrigerating chambers.

Abstract: Fluid transfer apparatus comprising a fluid reservoir and a pump connected to the reservoir by a supply line, wherein the apparatus is configured so that vapor generated in the pump during periods of inoperation may escape from the pump cavity through the pump inlet, rather than being trapped in the pump cavity, and liquid may flow into the pump cavity from the supply line through the pump inlet to replace escaping vapor, thereby providing reliable pump start-up during intermittent operation. The apparatus may be employed to pump LNG for fueling of vehicles. Where LNG or another cryogenic fluid is being pumped, the pump is preferably driven by a motor located above the pump and connected thereto by an elongated shaft. Shaft seals may be provided to prevent the fluid being pumped from contacting the motor or the bearings supporting the motor shaft. A vapor trap may be provided beneath the shaft seals to prevent contact between liquid being pumped and the shaft seals.

Abstract: In a high side rotary compressor, liquid refrigerant is supplied to is to the compression chamber via a capillary tube and liquid injection port. The lubricant is delivered only after the suction port has closed and before chamber pressure exceeds the liquid injection supply pressure.

Abstract: Liquid refrigerant interacts with the stream of gas flowing through in a centrifugal water chiller, downstream of the occurrence of the compression process in the compressor portion of the chiller but prior to the condensing of the gas in the chiller condenser, to reduce the acoustic energy of the gas. The noise emanating from the chiller which would otherwise result from the interaction of the discharge gas with the piping connecting the compressor portion of the chiller to the system condenser and/or with the components of the system condenser itself is thereby reduced without significantly affecting chiller performance or efficiency.

Abstract: A protection system for electric motors in refrigerated environments, especially those environments cooled to very low temperatures, includes routing a cryogen coolant through the electric motor. A minimum flow of cryogen coolant is maintained through the motor to prevent ingress of moisture in the motor interior. The arrangement is especially useful with cryogenically cooled refrigeration systems, because the same cryogen coolant used to refrigerate the system can also be used to provide a purging flow of cryogen coolant gas through the electric motor.

Abstract: Liquid refrigerant is injected into the motor of a motor-compressor to cool the motor. Refrigerant is also injected to control the discharge temperature of the compressor. The refrigerant for controlling the discharge temperature may be either excess refrigerant for cooling the motor or refrigerant injected into the compressor under the control of a thermal expansion valve.

Abstract: A scroll-type compressor has a liquid injection system for injecting liquid into an enclosed space defined by first and second scroll members which engage in cyclical relative orbiting motion, to reduce the temperature of the working fluid. The compressor incorporates a discharge diffuser for reducing the pressure of the working fluid in an enclosed space, so that the liquid may be injected into the enclosed space from a more centrally located injection port than one which would allow liquid injection without the discharge diffuser.

Abstract: A liquid refrigerant pump includes a housing having a hollow interior for receiving liquid refrigerant, a motor disposed within the interior of the housing and connected to a source of power, a rotatable pump member disposed within the interior of the housing and a shaft interconnecting the motor and pump member for rotating the pump member to increase the pressure of the liquid refrigerant upon the motor receiving electrical power.

Abstract: Fluid transfer apparatus comprising a fluid reservoir and a pump connected to the reservoir by a supply line, wherein the apparatus is configured so that vapor generated in the pump during periods of inoperation may escape from the pump cavity through the pump inlet, rather than being trapped in the pump cavity, and liquid may flow into the pump cavity from the supply line through the pump inlet to replace escaping vapor, thereby providing reliable pump start-up during intermittent operation. The apparatus may be employed to pump LNG for fueling of vehicles. Where LNG or another cryogenic fluid is being pumped, the pump is preferably driven by a motor located above the pump and connected thereto by an elongated shaft. Shaft seals may be provided to prevent the fluid being pumped from contacting the motor or the bearings supporting the motor shaft. A vapor trap may be provided beneath the shaft seals to prevent contact between liquid being pumped and the shaft seals.

Abstract: A cryogenic station for delivering a cryogen substantially free of higher boiling impurities. The cryogenic station includes an insulated main tank and an auxiliary tank. Liquid stored in the main tank and pressurized by a pressure building circuit is driven into the auxiliary tank. Cryogenic vapor formed in the auxiliary tank is warmed to ambient temperature by an external heat exchanger and is then recirculated back to an internal heat exchanger located within the auxiliary tank. The internal heat exchanger is configured such that a portion of the cryogen driven into the auxiliary tank is vaporized to form the cryogenic vapor and a remaining portion of such cryogen is left within the auxiliary tank to substantially retain the higher boiling impurities in a solidified state. As such, the cryogenic vapor is substantially free from the impurities when delivered as a product stream.

Abstract: An expansion chamber with a connection to an airgun employing carbon dioxide or similar gas as a propellant. The expansion chamber is normally connected to a source of liquified gas, included therein is a structure for separating liquified gas into the gaseous state for use as a propellant. Any remaining liquid portion is retained until it is converted into the gaseous state.

Abstract: A multistage centrifugal compressor, comprising a casing having an inlet portion and a compression portion. The inlet portion has an inlet opening gaseously coupled to an evaporator so as to receive a gaseous refrigerant. The inlet and compression portions each have a plurality of gas passages therethrough. The compression portion has an outlet opening that is located at the end of the casing which is opposite the end of the casing having the inlet opening. An electric motor assembly is positioned within the inlet portion of the casing so as to provide a transfer of heat dissipated by the motor assembly to the gaseous refrigerant entering through the inlet opening. The gaseous refrigerant flowing in the inlet opening passes through and about the motor assembly so as to cool the motor assembly.

Abstract: An improved motor driven centrifugal refrigerant compressor is disclosed having a housing enclosing a motor, control electronics and moving parts of the compressor, and a fluid pathway for circulating a mixture of low pressure refrigerant and a lubricant around the pathway, the pathway including a lubricant concentrator for coalescing the lubricant of the mixture to lubricate moving parts of the compressor and the pathway also including a convective heat transfer region to cool the motor and control electronics within the housing.

Abstract: A superconducting rotating apparatus has a rotor constituted in a cryostat structure and comprising a cold rotor and a superconducting winding to be cooled by coolant, a heat shielding member for heat-shelding the cold rotor, a magnetic coupling device for coupling the cold rotor to a rotational shaft in a non-contact means by a magnetic force, a field current source for supplying field current to the superconducting winding, a stator disposed in space at a predetermined interval from the cold rotor and having an armature winding, and a refrigerator provided in the rotor to cool coolant introduced into the superconducting rotor and warmed up by cooling the superconducting winding.

Abstract: A scroll-type refrigerant compressor for use in a conventional refrigerating circuit and having liquid refrigerant compressor cooling provided by the injection of liquid refrigerant into an intermediate biasing chamber and/or specifically located bleed holes.

Abstract: A rotary compressor such as a screw-type or a spiral compressor comprises a compressor stator and one or more rotary compression elements, which compressor stator is provided with a suction port, a delivery port and a lubricant inlet, the lubricant being intended for lubricating each compression element, for sealing the gaps between the individual compression elements and between the compression elements and the compressor stator, and for cooling the medium to be compressed during the compression process. The compressor also comprises an inlet for a cooling medium for cooling the lubricant which opens out near or in the delivery port.

Abstract: There is provided an air-conditioning apparatus. A cooling bypass extends from a pipe portion between a water heat exchanger and indoor heat exchangers of a refrigerating cycle to a low-pressure-side pipe portion of the refrigerating cycle. The cooling bypass is provided with a flow control valve. A discharged-refrigerant temperature Td and sucked-refrigerant temperature Ts of a compressor are sensed, and the opening degree of the flow control valve is zone-controlled in accordance with temperature Td or temperature Ts. When the sucked-refrigerant temperature Ts exceeds a predetermined value despite the zone-control, the opening degree of the flow control valve is controlled and increased. By this control, the amount of refrigerant flowing through the cooling bypass increases, and the refrigerant cooling effect on the low pressure side is enhanced.