Abstract: Just before shutdown, or at least prior to a significant pressure equalization in a refrigeration system, an accumulator containing oil is isolated from the rest of the refrigeration system in such a way that oil is at a pressure that is higher than the pressure of the rest of the system. The oil in the accumulator is maintained in a state of higher pressure while the refrigeration system is shutdown with the aid of a spring-loaded piston. Preliminary to start up of the refrigeration system, the pressurized oil is placed in fluid communication with structure requiring lubrication which is thereby lubricated.

Abstract: Hydrofluorocarbon refrigerants are not soluble in hydrocarbon oil. Retrofitting refrigeration equipment with hydrofluorocarbons generally entails the use of expensive polyol ester (POE) lubricants. The invention provides hydrofluorocarbon refrigerant compositions that are soluble in hydrocarbon oil thus allowing for a simpler and less expensive retrofit option to the refrigerant user.

Abstract: A refrigerant mixture for a mixture throttle process contains from 0.06 mol/mol to 0.20 mol/mol propane, from 0.26 mol/mol to 0.36 mol/mol nitrogen and from 0.20 mol/mol to 0.38 mol/mol methane, the remainder being ethane.

Abstract: A conduit for transporting non-volatile liquids is provided in which the conduit's internal surfaces have a surface energy lower than that of the nonvolatile liquid.

Abstract: A helical screw compressor is provided having a first compressor stage and a second compressor stage. The helical screw compressor includes a first male rotor and a first female rotor in the first compressor stage, and a second male rotor and a second female rotor in the second compressor stage. A connecting duct is provided between an outlet of the first compressor stage and an inlet of the second compressor stage, and a conduit is provided having a first end communicating with the connecting duct and a second end branching off into a first line and a second line. The first line is coupled to the first compressor stage for injecting liquid into the first compressor stage, and the second line is coupled to the second compressor stage for injecting liquid into the second compressor stage.

Abstract: An oil separator comprising a cylindrical portion, an inlet for incoming gas/oil mixture, an outlet for separated gas, a lower portion, and an outlet for separated oil is provided. The lower portion decreases in diameter as it proceeds from top to bottom, thereby providing for an increase in centrifugal force within the oil separator and greater separation of oil. The inlet traverses an upper wall of the oil separator, and preferably comprises a plurality of passageways angled with respect to the upper wall.

Abstract: Compressors for air conditioning systems may compress fluids that contain a mixture of a refrigerant and a lubricating oil. The lubricating oil may primarily consist of polyvinyl ether (PVE) oil and may be used for an air conditioning system. Such fluids preferably minimize the degradation of the electrical insulation properties of a vehicle air conditioning circuit.

Abstract: The present invention relates to the art of refrigeration and more particularly to a method of regulating the cooling process by controlling the oil pressure in a compressor. The system prevents the accumulation of the liquid refrigerant in the crankcase of the compressor and allows a compressor to continue to work without interruption.

Abstract: A refrigerant fluid is placed within a driveline component, and in particular an axle housing. This refrigerant fluid is received within a sealed reservoir such that it is sealed from the typical lubricant in the driveline component. The lubricant heats the refrigerant through a housing such that the refrigerant vaporizes within the driveline component housing, thus cooling the lubricant. The vaporized refrigerant travels to a cooling chamber mounted remotely from the reservoir. The cooled refrigerant is cooled to a liquid state, and then returned to the reservoir. Preferably the cooling chamber is positioned on the vehicle frame vertically above the driveline component.

Abstract: The invention relates to a method for regulating a fan in a compressor unit which comprises at least one compressor element (1), a motor (2), and a cooler (14,17) which comprises at least one radiator (13,16) and a fan (18) cooperating therewith, driven by an electric motor (19), whereby the motor (2) of the compressor element (1) is driven at a speed varying in function of its load and also the number of revolutions of the motor (19) of the fan (18) is regulated in function of the required cooling, however, such that condensation of moisture by exaggerated cooling is avoided. The unit comprises means (21) for regulating the speed of the motor (1) in the aforementioned manner.

Abstract: A conduit for transporting non-volatile liquids is provided in which the conduit's internal surfaces have a surface energy lower than that of the non-volatile liquid.

Abstract: A highly reliable refrigeration cycle having a residual refrigerant, which is designed that the refrigerating machine oil does not stagnate in the refrigeration cycle after flowing out from the compressor even if the refrigerating machine oil is weakly soluble in a refrigerant. Thus, the compressor may be prevented from the exhaustion of oil. In addition to that, even if the accumulator is removed from the cycle, a large amount of wet vapor suction into the compressor may also be avoided. A control section is provided for controlling saturated oil solubility in a liquid refrigerant in the refrigeration cycle. The control section includes a receiver and first and second flow regulators which are placed before and after, respectively, the receiver. A residual liquid refrigerant obtaining in the circulation of a refrigerant is reserved in the receiver at a high temperature so that the weakly soluble refrigerating machine oil is prevented from separating.

Abstract: A supply canister is partially filled with a refrigerant circuit additive liquid and is partially evacuated. Additive liquid from the canister may be placed into the refrigerant circuit of an air conditioning system by (1) connecting the canister to the circuit after it has been emptied and a vacuum pressure created therein, (2) connecting the canister to the refrigerant circuit suction line during system operation, or (3) connecting the canister to the suction line with the system off, to thereby force refrigerant from the circuit into the canister, and then starting the system to cause the vacuum pressure in the suction line to draw the contents of the canister into the refrigerant circuit.

Abstract: An air conditioner (1) includes an air conditioning circuit (2) in which a cooling medium circulates. An electrically powered compressor (C) is disposed within the air conditioning circuit (2) for compressing the cooling medium and discharging the cooling medium under high pressure. A refrigerant superheat feedback device (22) adjusts the superheat condition of the cooling medium that is returned to the compressor (C) for compression in order to ensure an adequate supply of lubrication oil to the compressor (C).

Abstract: Just before shutdown, or at least prior to a significant pressure equalization in a refrigeration system, an accumulator containing oil is isolated from the rest of the refrigeration system in such a way that oil is at a pressure that is higher than the pressure of the rest of the system. The oil in the accumulator is maintained in a state of higher pressure while the refrigeration system is shutdown with the aid of a spring-loaded piston. Preliminary to start up of the refrigeration system, the pressurized oil is placed in fluid communication with structure requiring lubrication which is thereby lubricated.

Abstract: Oil return from the evaporator to the compressor of a refrigeration chiller is accomplished by routing the suction piping that communicates between the chiller's evaporator and compressor to a location physically below the lubricant-rich pool at the bottom of the evaporator shell and by connecting the lubricant-rich pool to the compressor suction piping at a location where the suction piping is disposed physically below the pool.

Abstract: A blower supplies compressed air to a predetermined place. The blower is provided with a plurality of compressors, a common air tank for storing compressed air supplied from the compressors, a changeover valve for switching the compressed air taken in from the air tank between a first supply state and a second supply state, and a controller for controlling operations of the compressors and the switching operation of the changeover valve. The controller can select one operation pattern from among a plurality of operation patterns determined by combinations between the compressors and the changeover valve.

Abstract: Oil return from the evaporator to the compressor of refrigeration chiller is accomplished by routing the suction piping that communicates between the chiller's evaporator and compressor to a location physically below the lubricant-rich pool at the bottom of the evaporator shell and by connecting the lubricant-rich pool to the compressor suction piping at a location where the suction piping is disposed physically below the pool.

Abstract: Oil return from the evaporator to the compressor of a refrigeration chiller is accomplished by routing the suction piping that communicates between the chiller's evaporator and compressor to a location physically below the lubricant-rich pool at the bottom of the evaporator shell and by connecting the lubricant-rich pool to the compressor suction piping at a location where the suction piping is disposed physically below the pool.

Abstract: A system for generating refrigeration wherein a multicomponent refrigerant is compressed in a compressor lubricated with polyalphaolefin-based oil, the oil is removed from the compressed refrigerant, and the compressed refrigerant is expanded to generate refrigeration at a cryogenic temperature for provision to a refrigeration receptor.

Abstract: A falling film evaporator for use in a vapor compression refrigeration chiller preferably employs a two-phase refrigerant distributor that overlies the tube bundle in the evaporator shell. The tube bundle defines at least one vapor lane which facilitates the conduct of refrigerant vapor from the interior of the tube bundle to the exterior thereof in a manner which does not substantially affect the vertically downward flow of liquid refrigerant through the tube bundle and across the vapor lane.

Abstract: A refrigerating apparatus comprising a refrigeration cycle comprising at least a compressor, a condenser, a dryer, an expansion mechanism and an evaporator, a refrigerant composed mainly of a fluorocarbon type refrigerant containing no chlorine and having a critical temperature of 40° C. or higher, and a refrigerating machine oil comprising as base oil an ester oil of one or more fatty acids which contains at least two ester linkages in the molecule and has a viscosity at 40° C. of 2 to 70 cSt and a viscosity at 100° C. of 1 to 9 cSt.

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: An internal oil separator for compressors of refrigeration systems is disclosed. This oil separator supplies an effective quantity of lubrication oil to the drive parts of a compressor, and protects the compressor from being unexpectedly damaged or locked. The oil separator accomplishes the recent trend of compactness of compressors, and prevents a bypass flow of the compressed refrigerant into the compressor. This oil separator collaterally reduces operational noises of the compressor. In this oil separator, an oil-separating chamber 21, having a generally U-shaped passage, is defined in the rear section of a compressor housing by a cover 2. The oil-separating chamber 21 has a guide wall 22, thus forming a desired U-shaped passage therein. Refrigerant inlet and outlet ports 13, 14 are formed on the rear wall of the housing. An oil-collecting part 17 is formed on the bottom of the oil-separating chamber 21 and stores recovered oil therein.

Abstract: A refrigeration chiller makes use of the flow of oil from an oil sump location to the chiller's compressor to power an eductor to return oil which has made its way to the evaporator of the chiller system from the evaporator to the compressor.

Abstract: Lubrication supply to the rotors of a variable speed screw compressor is optimized for full load and a supplemental supply path is provided which is opened during low speed operation.

Abstract: A two-step process comprising as a first step draining a refrigerant heat transfer fluid made of molecules containing at least one chlorine atom per molecule and mineral oil lubricant dissolved therein from an unflushable compressor and associated piping in a vehicle air conditioner, thereby leaving a mineral oil residue. The second step comprises replacing the refrigerant heat transfer fluid in all parts of the vehicle air conditioner designed to contain such fluid with a replacement heat transfer fluid. The replacement fluid consists essentially of 1,1,1,2-tetrafluorethane and a composition of matter suitable for serving as the lubricant or lubricant base stock. The composition of matter is capable of forming a soluble clear solution with a mineral oil residue in a weight ratio of mineral oil to composition of at least 25:100 and forming a single phase with 1,1,1,2-tetrafluoroethane between −55° C. and +71° C.

Abstract: A refrigeration chiller employs a centrifugal compressor the impellers of which are mounted on a shaft which is itself mounted for rotation using rolling element bearings lubricated only by the refrigerant which constitutes the working fluid of the chiller system. Apparatus is taught for providing liquid refrigerant to (1.) the bearings immediately upon chiller start-up, during chiller operation and during a coastdown period subsequent to shutdown of the chiller and (2.) the drive motor of the chiller's compressor for motor cooling purposes. By use of a variable speed-driven motor to drive the compressor, optimized part load chiller performance is achieved in a chiller which does not require or employ an oil-based lubrication system.

Abstract: Oil is returned from the evaporator to the oil sump in a refrigeration chiller by directing the lubricant-liquid refrigerant mixture found in the chiller evaporator into heat exchange contact with relatively hotter system lubricant as such lubricant flows from the oil sump to the location of its use in the chiller's compressor. The oil flowing from the sump to the compressor rejects sufficient heat to the lubricant-liquid refrigerant mixture to induce the percolation thereof, such percolation being sufficiently energetic to cause slugs of the lubricant-liquid refrigerant mixture to be delivered from the location of heat exchange into the chiller's lubricant sump thereby effecting the return of oil from the evaporator for re-use in the compressor.

Abstract: In a compressor of a refrigeration cycle using an HC-based refrigerant and a lubricant having specific gravity greater than that of the HC-based refrigerant and having no or no or less mutual solubility with the HC-based refrigerant, an oil reservoir is formed on a bottom of the compressor, the oil reservoir is provided at its portion with a recess, a suction port of a lubricant suction pipe for supplying the lubricant to a compressor mechanism is provided in the recess. With this feature, it is possible to sufficiently supply the lubricant to the compressor even when the lubricant has no or less mutual solubility, so that even if the amount of the lubricant is reduced, the lubricant can be sufficiently sucked from an inlet port of a lubricant pumping pipe and supplied to the compressor mechanism.

Abstract: A method for operating a motor vehicle air conditioner includes starting a compressor, and lubricating the compressor with a circulating lubricant for at least a specified minimum lubricating time.

Abstract: The invention is a method and apparatus for cooling compressor oil in a refrigeration system by passing the oil through a heat exchanger cooled by evaporating refrigerant. The refrigerant is pumped into the heat exchanger by a liquid refrigerant pump. The use of the pump avoids the requirement of a mixing pipe with an internal venturi nozzle, while also providing oil-cooling that is relatively free of noise and disturbance to those in the vicinity of the refrigeration unit.

Abstract: A conduit is coupled to an oil accumulator with an orifice coupled in series with the conduit for limiting the flow of oil therethrough. A pressure sensor is coupled to the conduit for measuring the pressure in the conduit. An oil drain control solenoid valve is coupled to an electrical circuit also coupled to the pressure sensor for selectively opening the oil drain for the draining of oil into a collection tank without losing refrigerant.

Abstract: A capacity type refrigerant compressor having a compression chamber in which a refrigerant introduced from a suction system is compressed and discharged as a compressed high pressure refrigerant, and an oil-separating and lubricating system for lubricating an interior of the compressor by an oil separated from the compressed refrigerant, which has an oil-separating unit to separate the oil from the compressed refrigerant, an oil-storing chamber storing the separated oil, an oil-supply passage to supply the oil from the oil-storing chamber to the suction system, a pressure-operated valve arranged in the oil supply passage to regulate an amount of flow of the oil, which includes a valve chamber and a movable valve spool in the valve chamber to control a communication between the upstream and downstream of the oil-supply passage.

Abstract: A device for separating oil from an oil/gas mixture in a refrigeration or heat pump system includes a cylindrical housing circumscribing a central axis with upper and lower end caps. A scroll-shaped separator baffle disposed in the housing defines a flow path extending radially-inward in a spiral manner from a peripheral region of the housing toward the central axis of the housing. An inlet conduit in the upper end cap directs an oil/gas mixture into the housing. An upper baffle plate supporting an upper end of the separator baffle directs the oil/gas mixture from the inlet to the peripheral region of the housing and into the separator baffle. The oil in the mixture generally separates from the gas in the mixture and deposits on the wall of the separator baffle the mixture flows radially inward through the separator baffle. An outlet conduit in the lower end cap aligned with the central axis and extending upwardly into the separator baffle directs the resulting oil-free gas stream from the housing.

Abstract: A refrigeration system having compressors positioned higher than the dispersed evaporators requires multiple suction risers. To better ensure oil return to the compressors, only a single oil return riser is employed. This oil return riser is connected to one end of an oil collection main positioned near the lower portion of the suction risers. The oil collection main is connected by restricted oil drain conduits to the lower portions of the suction risers, thereby collecting the oil which failed to be conveyed to the top of the suction risers by their vapor velocity. The restrictions in the oil drain conduits ensure adequate vapor velocity within the oil collection main even with widely varying loads on the suction risers.

Abstract: An assured supply of lubricant to the compressor in a refrigeration chiller is provided by a reservoir that is connected in parallel with the main line by which lubricant is supplied to the compressor. The reservoir is connected to the main lubricant supply line in a manner such that if the lubricant supply line is blown dry, as can occur as a result of an unusual or abnormal chiller shutdown condition, a critical portion of the supply line will be refilled by the reservoir relatively very quickly which assures the immediate availability of lubricant to the compressor from that portion of the lubricant supply line when it next starts up.

Abstract: A compressor oil recovery device for use in removing oil from compressors typically found on condensing units used in air conditioning or refrigeration applications is disclosed. The device consists of a canister with a lid that contains a vacuum port, a suction port, a drain port, and a vacuum release port. A vacuum hose is connected at one end to the vacuum port and at the other end to an electric vacuum pump. A suction hose is connected at one end to the suction port and at the other end to the gauge manifold of a compressor. Upon activating the vacuum pump, a vacuum is created that draws the compressor oil into the canister where it is collected for disposal.

Abstract: Oil cooling is accomplished in a refrigeration chiller by flowing hot oil into heat exchange contact with liquid refrigerant which is sourced from the chiller's condenser and returned thereto. The rejection of heat from the oil to the refrigerant in an oil-cooling heat exchanger causes vaporization of the refrigerant and, in turn, creates a density difference in the refrigerant flowing from the condenser and refrigerant in and downstream of the oil-cooling heat exchanger. This density difference is responsible for inducing and maintaining refrigerant flow through the heat exchanger for oil cooling purposes.

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: 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 refrigerating apparatus comprising a refrigeration cycle comprising at least a compressor, a condenser, a dryer, an expansion mechanism and an evaporator, a refrigerant composed mainly of a fluorocarbon type refrigerant containing no chlorine and having a critical temperature of 40.degree. C. or higher, and a refrigerating machine oil comprising as base oil an ester oil of one or more fatty acids which contains at least two ester linkages ##STR1## in the molecule and has a viscosity at 40.degree. C. of 2 to 70 cSt and a viscosity at 100.degree. C. of 1 to 9 cSt.

Abstract: The present invention provides a compressor in which an oil for application or that for assembly has non-compatibility with a refrigerant to be charged in a refrigerant circuit and an lubricating oil to be charged in the compressor has compatibility with the refrigerant.

Abstract: An ester blend, including an ester having neopentylglycol and a source of 2-ethylhexanoic acid as its reactive components and an ester having pentaerythritol and a source of 2-ethylhexanoic acid as its reactive components, is especially effective as a lubricant for chlorine-free fluorocarbon refrigerant heat transfer fluids, particularly Refrigerant 134a (1,1,1,2-tetrafluoroethane).

Abstract: An air conditioning apparatus includes a compressor, an interior side heat exchanger, an exterior side heat exchanger, an expansion device provided between the interior side heat exchanger and the exterior side heat exchanger, a four-way valve provided between the compressor and the interior side heat exchanger and between the compressor and the exterior side heat exchanger, an oil separator provided between a delivery outlet of the compressor and the four-way valve, a first restrictor and a second restrictor provided between the oil separator and a suction inlet of the compressor, and an open-close valve provided between the second restrictor and the suction inlet of the compressor.

Abstract: An air conditioner has an outdoor unit and a plurality of room units supplied with a refrigerant from the outdoor unit. The outdoor unit and the room units are connected by a plurality of refrigerant pipes. In a recovery operation for returning refrigerator oil from the room units, the refrigerant pipes and the like to the outdoor unit, the plurality of room units are divided into a plurality of room unit groups, and the recovery operation of the refrigerant is carried out for each of the room unit groups.

Abstract: In a refrigerant circulating apparatus, a liquid accumulating container for allowing oil droplets to flow out in suspended form is connected between a condenser and a pressure reducing device. Thus, refrigerating machine oil which flowed out from a compressor can be reliably returned to the compressor, and proper lubricating and sealing functions can be maintained for the compressing elements.

Abstract: An apparatus and method wherein ozone layer-damaging dichlorodifluoromethane is substituted with a mix of less environmentally damaging refrigerants chlorodifluoroethane and tetrafluoroethane in dichlorodifluoromethane-based air-cooling systems. While less environmentally damaging than dichlorodifluoromethane, the substitute refrigerant has a temperature-pressure relationship similar to that of dichlorodifluoromethane, making the substitute refrigerant suitable for use with dichlorodifluoromethane-based air-cooling systems. The substitute refrigerant can be used alone or in combination with dichlorodifluoromethane. In either event, it is mixed with a relatively small percentage of a hydrophobic lubricating oil which is compatible with both the substitute refrigerant and with dichlorodifluoromethane.

Abstract: A method for controlling oil viscosity in a refrigeration unit having an oil viscosity effecting parameter with a desired set point. The refrigeration unit includes an oil lubricated compressor having a capacity and a suction pressure, a condenser, refrigerant control valves, and an evaporator connected in series, for circulating a refrigerant for adjusting air temperature of a compartment.

Abstract: An expansion/separation compressor system is presented for a multi-rotor compressor configuration. In accordance with the present invention the rotors are disposed in a shell having open and closed off portions for providing expansion, compression and separation. The closed off portions depend from or are attached to other suitable compressor structure including the induction or discharge plates. In an embodiment the expansion portion is comprised of a sliding valve. Separation is achieved when the flute and respective open shell portion expose the fluid to basic plenum pressure. The fluid is essentially removed by centrifugal force through the opening in the shell. The compressor is mounted to an evaporator and a control system is provided to regulate the temperature of water in the evaporator thereby controlling the rate of evaporation of liquid phase refrigerant in the evaporator. The liquid phase refrigerant is expanded between the rotors and respective shell portions to a desired volume.