Abstract: The installation comprises an insulated storage tank (1) containing the gas in at least partially liquid form at a high pressure, a line (2) comprising a vaporizer (3) for supplying gas to a user station (A), a first cold-holding circuit (4), comprising a valve (5) and a first exchanger (6) in heat-exchange contact with the fluid in the first tank (1), and a pressure-holding line (8) comprising a second exchanger (9) and a valve (10). The system is particularly useful as a backup installation for a main gas-production source (30).

Abstract: A compression refrigerating machine for enabling an alternative refrigerant to be used by removing water content or chlorine which may be mixed into a lubricating oil. The compression refrigerating machine includes a vaporizer, a condenser, a compressor for compressing a refrigerant gas from the vaporizer, a drive source for driving the compressor, a lubricating oil line in which a lubricating oil is circulated and a refrigerant line in which a refrigerant is circulated. The lubricating oil line provides with a device for removing water content or for removing chlorine.

Abstract: In a refrigeration or air-conditioning process, a method applicable to the replacement of potentially ozone-depleting oil-miscible refrigerants such as R-12 with non-ozone-depleting oil-immiscible refrigerants such as R-134a, wherein a conventional expansion device is replaced by a self-regulating pulsed nozzling device for pulsed circulation of the immiscible oil in the new refrigerant to create accelerated intermittent high velocity bursts of substantially unrestricted refrigerant flow imparting sufficient momentum to move the oil with the refrigerant through all stages of the process.

Abstract: A bottom feed accumulator canister for an automotive air conditioning system includes a novel means to prevent drain down when the system compressor is off. A valve chamber located at the bottom of, and to one side of, the accumulator return tube surrounds a small bleed orifice through the tube. A valve seat in the valve chamber holds a weight that is sufficiently massive to block the valve seat against liquid ingress when the compressor is off. When the compressor is on, the suction at the bottom of the return tube is also seen in the valve chamber, lifting the weight so that liquid can be drawn into the tube through the small orifice.

Abstract: A method of assembling a closed loop refrigerating air conditioning system using a hydrofluorocarbon refrigerant by applying a first oil which is insoluble with the hydrocarbon refrigerant to components of a compressor, and storing the insoluble oil within the housing of the compressor in a single or mixed state.

Abstract: A process and apparatus for transfer of liquefied natural gas from a storage tank in subcooled condition using liquefied nitrogen to subcool the liquefied natural gas and nitrogen vapor formed by thermal transfer between the liquefied natural gas and liquefied nitrogen as pressurant to drive the transfer of subcooled liquefied natural gas. This invention provides a liquefied natural gas vehicle refueling station which utilizes nitrogen as a propellant and avoids venting natural gas to the atmosphere.

Abstract: The fluid management system comprises a mixing/recirculation system including an external recirculation pump for receiving fluid from a zero gravity storage system and returning an output flow of the fluid to the storage system. An internal axial spray injection system is provided for receiving a portion of the output flow from the recirculation pump. The spray injection system thermally de-stratifies liquid and gaseous cryogenic fluid stored in the storage system.

Abstract: An oil management system for a refrigeration system having a screw compressor for pressurizing and circulating refrigerant through the system and an evaporator having a shell enclosing a chamber for allowing phase change of the refrigerant. A suction line is provided to fluidly connect the evaporator chamber to the inlet side of the compressor. The suction line is sealed about an opening in the shell and has a distal end projecting into the chamber below the seal. A reservoir is positioned within the chamber, below the suction line. The reservoir is employed for collecting lubrication oil migrating down the suction line during low load operation of the compressor so that when the level of oil in the reservoir reaches a predetermined level, the opening in the distal end of the line will be restricted thereby increasing the flow velocity proximate thereto causing reintroduction of the oil into the compressor.

Abstract: In a cryostat with a liquefaction refrigerator, an object to be cooled, as well as a low-temperature end of the liquefaction refrigerator for cooling the object to be cooled, is contained in a thermally-insulated vessel. The liquefaction refrigerator comprises a cooler and a refrigerator, and the cooler comprises, as main components, a heat exchanger and an expansion valve. The refrigerator includes a mechanically-operated cold-generating device. Within a vacuum vessel in the cryostat, the cooler and the refrigerator are thermally connected together by a releasable thermally-conductive member. Since the refrigerator and the cooler are separate from each other, they can be overhauled independently of each other, and the cooler can be of a compact and lightweight design. Therefore, there can be provided the cryostat which is low in running cost, and has an excellent cooling performance.

Abstract: A superconducting magnet which is capable of improving the refrigerating and the assembling characteristics and of composing in small size. A helium vessel 2 contains a cylindrical superconducting coil for cryogenically refrigerating it by liquid helium. A second and a first heat-shields 5 and 6 and a vacuum vessel 4 are coaxially provided so as to surround the helium vessel 2. Over the helium vessel 2, a L-letter shaped duct 50 is provided to be exposed to helium gas atmosphere being evaporated in the helium vessel 2. A refrigerator-mounting cylinder 51 has an end coupled to the L-letter shaped duct 50 through the bellows 52 and is mounted on an end surface of the vacuum vessel 4 substantially in parallel to the axial direction of the superconducting coil. A three-stage cold heat accumulation refrigerator 30 is inserted into and fixed to the refrigerator-mounting cylinder 51 for reliquefying the helium gas having been drawn into the L-letter shaped duct 50 by a third heat state 43.

Abstract: A method is disclosed for the reduction of emissions of solvent vapors from a batch mixing vessel by cryogenically condensing such vapors in and adjacent the top loading hatch at a rate approximating their evaporation from the mix.

Abstract: In a multi-stage cold accumulation type refrigerator including a compressor disposed at an ordinary temperature, a helium gas as a common operating fluid to be compressed by the compressor, and one or more expansion chambers and cold accumulators of different temperature levels; a cold accumulating member of the cold accumulators is formed of an alloy or compound containing a rare earth metal, so that the efficiency of the refrigerator can be improved. Further, a heat generation quantity due to sliding resistance of a seal is set to be smaller than a theoretical generated refrigeration quantity to be obtained on the assumption of isothermal expansion in the expansion chambers, so that the refrigerating capacity can be improved. The refrigerator is applied to a cooling device for cooling a superconducting magnet, SQUID, superconducting computer, infrared telescope, etc.

Abstract: An air conditioning system circulates a mixture of refrigerant fluid and lubricating oil. An accumulator is disposed upstream of a compressor to separate gaseous refrigerant from liquid refrigerant and oil. The accumulator includes an outer case, an inner case, an upstanding pipe, and a baffle plate disposed in the outer case and above the inner case. Gaseous refrigerant exits the accumulator through the pipe. Oil and possibly liquid refrigerant collect in the inner case around the pipe. Liquid refrigerant and possibly oil collect outside of the inner case. Each of the pipe and inner case include vertically spaced oil-return holes.

Abstract: A vaporless liquid containment system for storing volatile and other liquids while preventing the formation and escape of vapors. The vessel includes a base and a first membrane, the first membrane defines a fluid containment space for containing stored liquid. A fluid-tight gas containment space is located above the first membrane. The gas containment space is adapted to house a gas under pressure. As liquid to be stored is supplied to and withdrawn from the fluid containment space, the gas housed in the gas containment space supplies fluid pressure to the first membrane so that the pressure on the first membrane is maintained above the vapor pressure of the stored liquid. This prevents the formation of vapor caused by the evaporation of the stored liquid.

Abstract: A cryostat housing an ultra-low temperature medium includes a container for storing the ultra-low temperature medium, a pipe for communication between the inner and outer sections of the container, at least one tubular member interposedly arranged inside the pipe between the pipe and an opening, a heat anchor section for cooling the pipe, and a plate-shaped member positioned so that a gas layer of the ultra-low temperature medium inside the tubular member divides the tubular member longitudinally.

Abstract: In an apparatus for producing liquid nitrogen by supplying to a nitrogen gas separated from the atmosphere and then purified by an air separating device (4) into an insulated container (1) equipped with an extremely low temperature refrigerator, there are provided a pressure sensor (21) for detecting a pressure within a product vessel (20) of the air separating device (4) and a negative pressure sensor (16) for detecting a negative pressure within the insulated vessel (1) respectively. When at least one of both sensors (21) (16) detects a freezing of an impurity gas contained in the supplied nitrogen gas by reaching a predetermined pressure, an operation of the extremely low temperature refrigerator is stopped depending on the detection by one of both the sensors.

Abstract: A control apparatus for maintaining constant the temperature and pressure of the vapor phase in a very low-temperature controlled liquefied gas container includes a pressure sensor, a temperature sensor, two electromagnetic valves, and a refrigerator. When operation of the refrigerator disturbs measurement at low temperature, the refrigerator is stopped. Gas vaporizes from a liquid phase, and gas is discharged from the container. In this manner, the temperature and pressure of the liquefied gas in the container can be maintained constant. After measurement, the liquid level in the container will be lowered by evaporation, so that the liquefied gas is supplied to the container. In this manner, the liquid level in the container can be maintained constant.

Abstract: A vaporless liquid containment system for storing volatile and other liquids while preventing the formation and escape of vapors. The vessel includes a base and a first membrane, the first membrane defines a fluid containment space for containing stored liquid. A fluid-tight gas containment space is located above the first membrane. The gas containment space is adapted to house a gas under pressure. As liquid to be stored is supplied to and withdrawn from the fluid containment space, the gas housed in the gas containment space supplies fluid pressure to the first membrane so that the pressure on the first membrane is maintained above the vapor pressure of the stored liquid. This prevents the formation of vapor caused by the evaporation of the stored liquid.

Abstract: A fuel vapor recovery device having: a condenser in communication with fuel vapor from a fuel tank, the condenser condenses fuel from the fuel vapor; a reservoir collecting condensate from the condenser, the reservoir maintains the condensate at a temperature sufficient to maintain the condensate in a liquid state; and return means returning the condensate to the fuel tank. Also disclosed is a method of removing fuel from a fuel vapor including the steps of: passing the fuel vapor from a fuel tank through a condenser; condensing the fuel from the vapor; cooling the condensate to a temperature sufficient to maintain the condensate in a liquid state; and returning the condensate to a fuel tank periodically.

Abstract: A metering pump for metering low-boiling liquids, especially liquid anesthetics provides continuous metering of liquid. To achieve this, the pump chamber 7 is maintained at a temperature below the boiling point of the liquid by means of a cooling device 14, preferably a Peltier cell.

Abstract: A method and apparatus for delivering supercritical fluids uses one or two high pressure vessels. Each vessel is cooled below the critical temperature of the fluid while the vessel is being filled. The inlet is then closed and the vessel is heated to attain a predetermined pressure. The outlet of the vessel is then opened and supercritical fluid flows from the vessel for use in various processes such as extraction or chromatography. As the fluid flows from the high pressure vessel, the pressure is controlled by adjusting the temperature of the high pressure vessel. Usually, the temperature of the vessel will be increased as the supercritical fluid exits from the vessel. When two high pressure vessels are used, the vessels can be refilled on an alternating basis so that a continuous supply of supercritical fluid can be made available as long as it is required. The high pressure vessels can be two pieces of stainless steel tubing.

Abstract: The present invention relates to an apparatus for preventing evaporation of liquefied gas in a liquefied gas reservoir used for cooling an energy dispersive spectrometer type X-ray detector (EDS detector) and its control method. A cold head of a cryogenic refrigerator is disposed in an upper opening of the liquefied gas reservoir, the cryogenic refrigerator is adapted to be put into automatic operation depending on temperature inside the liquefied gas reservoir, wherein the automatic operation mode of the cryogenic refrigerator is put into rest by remote control during the use of the EDS detector, while the cryogenic refrigerator is put into automatic operation with a previous alarm issued when the temperature inside the liquefied gas reservoir increases over a set temperature with the EDS detector being out of use, thereby allowing vaporized gas to be reliquefied with gas consumption reduced.

Abstract: In a method and an apparatus for the precooling of a helium tank of a cryostat, in particular an optical cryostat with optical components in the helium tank, or an NMR cryostat, or a medical NMR cryostat for magnet resonance imaging, which accepts a superconducting magnet coil, a simple and cost effective precooling is achieved in that liquid nitrogen is directed out of a storage container under small overpressure via a conduit through an opening in the helium tank of a cryostat into a heat exchanger arranged in the helium tank and therefrom, by way of an opening, out of the cryostat and, finally, into a collecting container, in particular, into a nitrogen tank surrounding the helium tank.

Abstract: A system for transportation and storage of liquid carbon dioxide (CO.sub.2) at low pressures in the region of 1600-2300 KPa comprises a mobile supply tank (20a, 20b) and an on side storage tank (70). The mobile supply tank (20a, 20b) and the on site storage tank (70) are thermally insulated and each tank is refrigerated by a refrigeration system (71) with an evaporator located in the upper gas space of each tank. The on site storage tank (70) is filled with liquid CO.sub.2 by a conduit (36a) extending from near the bottom of the mobile supply tank (20a, 20b) via a filling port (72) on the on site storage tank to an opening near the bottom of the on site storage tank. A closed circuit system is achieved by a further conduit (37a) extending via an outlet port (73) from the gas space near the top of the site storage tank (70) to a gas space near the top of the mobile supply tank (20a, 20b).

Abstract: A trailer with piping and accessories capable of maintaining the ultra high purity of a cryogenic liquid while receiving and transporting the liquid, purging an external receiver, and transferring liquid to the receiver. The trailer has a heat exchnger for vaporizing a liquid flow from its liquid container into warmed gas. The gas is used for purging an external receiver and for pressurizing the liquid container sufficiently to transfer liquid into the purged receiver. The trailer piping allows purging of and then transferring to the receiver without opening any connections. The number of welded surfaces in the trailer capable of trapping and generating contaminants are reduced, particularly the number of welded penetrations of the liquid container.

Abstract: A device for preventing evaporation of liquefied gas in a liquefied gas reservoir used to cool an EDS detector of an electron microscope or the like is disclosed. A cold head of a cryogenic refrigerator is disposed so as to fit an opening of the top of the liquefied gas reservoir and moreover a temperature measuring instrument or a level gauge is disposed within the liquefied gas reservoir so that the cryogenic refrigerator is automatically operated depending on the temperature within the liquefied gas reservoir or on change in the liquid level of liquefied gas. In the manner vaporized gas is condensed and reliquefied, thus suppressing wasteful dissipation of vaporized gas.

Abstract: Liquefaction apparatus and method for removing liquid molecules from a vaporous or gaseous medium, use being made of an annular porous layer (5) of van der Waals-type material through which the medium is radially outwardly directed, the layer being rotatably driven to discharge by centrifugal force the liquid modules that are bound by van der Waals forces in the layer. The layer is mounted concentrically on the inner periphery of a rotatably driven cylindrical separator member (4) having an annular wall portion provided with a passage system at least the outlet portion of which terminates in a plurality of radial passages (17) through which the liquid molecules are centrifugally discharged. In one embodiment, the separator member is cooled by a cooling bath (18) the liquid of which is recirculated through a refrigeration-type heat exchanger (12).

Abstract: In a cryostat comprising a cryogen container for containing a liquid cryogen, and a refrigerator for recondensing a cryogen gas resulting from evaporating of the liquid cryogen, the pressure within the cryogen container is detected, and when the pressure falls to a negative value due to excessive cooling, a heater is turned on to raise the temperature thereby to enhance the evaporation. As an alternative, the refrigerator may be turned off or its power may be lowered. This will increase the pressure within the cryogen container. When the pressure rises to a positive value, the heater is turned off or the refrigerator is turned on or its power is raised. Through such control, the pressure can be maintained at a constant, positive value. As a result, deformation of the cryogen container due to pressure variation is avoided, and deformation of the superconducting coil wound on the cryogen container is avoided, and the magnetic field strength and the magnetic field uniformity can be maintained constant.

Abstract: In a multi-stage cold accumulation type refrigerator including a compressor disposed at an ordinary temperature, a helium gas as a common operating fluid to be compressed by the compressor, and one or more expansion chambers and cold accumulators of different temperature levels; a cold accumulating member of the cold accumulators is formed of an alloy or compound containing a rare earth metal, so that the efficiency of the refrigerator can be improved. Further, a heat generation quantity due to sliding resistance of a seal is set to be smaller than a theoretical generated refrigeration quantity to be obtained on the assumption of isothermal expansion in the expansion chambers, so that the refrigerating capacity can be improved. The refrigerator is applied to a cooling device for cooling a superconducting magnet, SQUID, superconducting computer, infrared telescope, etc.

Abstract: An improved vapor degreaser characterized by a deep freeboard zone (i.e., freeboard to width ratio of 1.0 to 2.3) containing a three-stage condenser/heat exchanger configuration comprising: a water-cooled lower primary exchanger operating above 32.degree. F. to effect condensation of the bulk of the vapor generated by the boiling sump and a combination of an intermediate exchanger above, but preferably overlapping, the primary exchanger and a dehumidifying third exchanger position just below the top lip of the degreaser, both operating at a temperature below 32.degree. F. (preferably +10.degree. to -30.degree. F.) to effect a reduction in the vapor concentration gradient that controls the rate of vapor diffusion through the freeboard zone. The improved vapor degreaser is particularly useful in reducing vapor losses when using low boiling solvents.

Abstract: Methods and apparatus are disclosed for taking advantage of a heat exchange relation between a liquid coolant and a protected liquid, whereby vaporization of the liquid coolant withdraws heat from the body of the protected liquid or an exterior heat source in order to prevent undue temperature rise within the body of the protected liquid.

Abstract: A fuel system for horizontal takeoff and hypersonic aerospace vehicles. The fuel vapor generated in the fuel tank is mixed with the liquid fuel from the tank. The mix is compressed and supplied to the engine system as usable fuel. The compressor used for compressing the combination gas and liquid can be driven from a turbo expansion cycle using aerodynamic heating of the vehicle. Several different embodiments for mixing the fuel vapor with liquid fuel are disclosed.

Abstract: A method and apparatus for removing oil and water contaminants from chloro-fluoro carbon refrigerants. This system is a single pass filtration system specifically designed for sealed systems with no atmospheric bleed off of chloro-fluoro carbons. This system incorporates a novel oil absorbent and is compact enough for small commercial applications, such as service stations or portable service of environmental control units. This system also incorporates a new cartridge type filter containing both water and oil and particulate absorbtion and removal means.

Abstract: An oil recovery system for refrigeration apparatus of the type in which an oil lubricated screw compressor is oriented with a suction inlet in communication with an evaporated chamber positioned under the compressor so that under conditions of low capacity compressor operation, lubricating oil may fall from the compressor through the suction inlet thereof and into the evaporator. The recovery system takes advantage of an existing suction distribution tray in the upper region of the evaporator chamber of such systems, normally used to assure distribution of gaseous refrigerant to the suction inlet of the compressor, by removing oil dropping into the tray and returning it back to the compressor. An existing by-pass eductor loop for returning liquid refrigerant from the evaporator to the compressor is extended by a valve controlled branch to a second eductor for withdrawing the oil from the tray and returning it to the compressor.

Abstract: A coolant for use in cryogenic devices of closed cycle system which comprises a mixture of a liquid nitrogen and a fluorocarbon of the formula: C.sub.n F.sub.2n+2, wherein n is an integer of 2 to 4. The coolant, when used to cool heat generating semiconductor devices and other devices to a cryogenic temperature, exhibits an increased heat flux and thus an increased cooling capability, in addition to a simple and small structure of the cooling system, and a prevention of environmental pollution.

Abstract: A cryostatic temperature regulator having a liquid nitrogen bath. The cryostatic temperature regulator is equipped with a cold head of a refrigerator which is coupled to the cover of the housing of the cryostatic temperature regulator in order to avoid gas losses.

Abstract: There is disclosed an atmospheric pressure dewar with an improved closure for the neck opening. The improvement comprises a cork positioned in the neck opening with a fibrous material occupying the peripheral space between the neck opening and the cork to inhibit convection flow of gases in the peripheral space when the dewar is oriented other than in the upright position.

Abstract: A Freon type refrigerant, which is vented from a heat exchange system, such as an air-conditioner, is transferred directly from the exhaust valve of the heat exchange system through a tube to a collecting cylinder or tank. The outer metal side walls of the collecting tank are wrapped with a chemically activatable cold wrap. The cold wrap may, for example, contain therein a rupturable pouch having a chemical blend of ammonium nitrate and urea to isolate same from water within the cold wrap. Upon rupturing of the pouch, the chemical blend is dissolved in the water and an endothermic reaction is initiated. As a result, the heat within the tank is absorbed therefrom by the cold wrap causing the temperature and pressure inside of the tank to drop. This permits substantially all of the refrigerant in the heat exchange system to be transferred into the chilled tank in a condensed or liquid state.

Abstract: This invention relates to a falling film evaporator which is arranged to cause a liquid film to flow downward to thereby effect heat exchange using evaporation. In a space of an evaporating compartment, a gas-liquid separator is disposed to communicate with a compressor which constitutes a part of a refrigeration cycle.

Abstract: A method and system for delivering high pressure, subcooled liquid carbon dioxide. An insulated tank having a height greater than its internal diameter holds liquid CO.sub.2 to a depth of at least about 6 feet, and high pressure, subcooled liquid CO.sub.2 is delivered from a lower outlet of the tank. CO.sub.2 vapor is condensed in the upper region to maintain a desired high pressure, e.g., about 290-310 psi., at the top of the tank. By withdrawing liquid CO.sub.2 from an upper region in the tank, subcooling it by heat exchange and returning subcooled liquid CO.sub.2 to a lower region, a thermocline region is created at least 2 feet below the surface, and above which equilibrium high pressure liquid CO.sub.2 exists. Heat exchange is efficiently carried out during off hours using liquid carbon dioxide to chill the condensed refrigerant from an existing auxiliary mechanical refrigeration unit.

Abstract: A heat pump system adapted to use a non-azeotropic refrigerant mixture preferably containing a high boiling temperature refrigerant as a primary component thereof is given an improved heat transfer efficiency and its pressure loss is minimized by arranging a refrigerant extracting means for removing the refrigerant stagnating in the system in an unfavorable state, in a vapor state in a condenser or in liquid state in an evaporator and returning the removed refrigerant into a refrigerant circulating passage of the system; and by constructing an evaporator of a flooded type at least at a portion adjacent to a refrigerant outlet portion of the evaporator.

Abstract: A refrigerant recovery system which includes a compressor having an input coupled through an evaporator and through a solenoid valve to the refrigeration system from which refrigerant is to be withdrawn, and an output coupled through a condenser to a refrigerant storage container. The evaporator and condenser are contained within a closed cylindrical canister for heat exchange and oil separation, the canister having an oil drain valve in the bottom. The refrigerant storage container is carried by a scale having a limit switch coupled to control electronics to prevent or terminate further refrigerant recovery when the container is full. The entire system, including the control electronics, is mounted on a two-wheel hand truck to facilitate transport to a job site such as a building air conditioning or heat pump system.

Abstract: A heat pump having reversible heating and cooling cycles for circulating a refrigerant therein for adding heat to and removing heat from space, the heat pump comprising a heat exchanger for adding heat to and removing heat from air passed over it, a condenser/evaporator coil for removing heat from or adding heat to refrigerant; and a compressor for circulating refrigerant. The heat pump further comprises a conduit for conducting refrigerant to the heat exchanger during the heating cycle and conducting refrigerant from the heat exchanger during the cooling cycle. A first line supplies the conduit with refrigerant during the heating cycle and is smaller than the conduit so that the refrigerant decelerates, causing oil that may have been picked up by the refrigerant to drop out. A second line also conducts refrigerant from the conduit during the cooling cycle. This line is larger than the conduit so that the refrigerant decelerates during, causing oil that may have been picked up by the refrigerant to drop out.

Abstract: The invention relates to a method for a refrigerant system having a circulation circuit comprising a screw compressor (1), a condenser (4), an expansion valve (5) and an evaporator (6). In a refrigerant process, in which an oil injected compressor is connected it is impossible to prevent oil from flowing together with the refrigerant out into the circulation circuit, which among others impairs the operation of the evaporator. According to the invention a drastic reduction of the amount of circulating oil has been obtained together with an improved cooling of the compressor by supplying the low pressure side of the compressor with refrigerant liquid with a pressure and temperature lower than the pressure and temperature of the refrigerant in the condenser in such amounts per unit of time that the required cooling and sealing of the compressor is obtained, the effect of the circulating oil being restricted merely to lubricating.

Abstract: An air conditioner including a cooling medium compressor, a condenser, an expansion valve and an evaporator, these being connected one another by a cooling medium capillary tube to circulate a cooling medium, whereby an oil returning mechanism of an evaporator for the air conditioner is characterized in that there is provided an oil reservoir for reserving a lubricating oil after oil separation at a lower part of the evaporator, the oil reservoir and an outlet tube for guiding the cooling medium passed through the evaporator to the cooling medium compressor being connected by an oil returning tube, the oil returning tube being provided with a controlling valve, when a pressure differential between the oil returning tube and the outlet tube is a predetermined level or more, the controlling valve being closed to enhance a normal flow of the cooling medium from the evaporator to the cooling medium compressor, when the pressure differential is a predetermined level or less, the lubricating oil staying in the oil

Abstract: This invention relates to a device for returning oil to at least one compressor (1) in a cooling or refrigerating system, in which the compressor sucks oil (16) from an oil collecting container (13) through at least one suction conduit (14) connected to the collecting container (13) and having one or more gas and oil intakes (15) which is or are situated above the oil level (16a) in the collecting container (13).

Abstract: A single or multiple evaporator vapor-compression refrigerant system for single or multi-story structures includes a lubricating oil collection reservoir and a separate oil pumping unit for returning oil separated from the refrigerant fluid in the refrigerant flow circuit to the compressor unit. In multi-story, direct expansion, vapor-compression, air conditioning systems, a simplified generally vertical refrigerant vapor return riser is provided with an oil reservoir at the lowest elevation point of the riser and a liquid level sensing switch for energizing and deenergizing the separate lubricating oil pumping unit. The pumping unit may include an electric or refrigerant fluid driven motor connected to a pump or the pumping unit may include a pressure vessel into which high pressure refrigerant vapor is admitted to displace oil back to the compressor through an oil return conduit.

Abstract: An improved oil return system for use with closed circuit mechanical refrigeration systems having multiple compressors. The oil return system is responsive to the flow of refrigeration gas to the individual compressors and enables an optimum flow of crank case oil to each of the multiple compressors. The system is based on the use of oil pick-up means for each of the suction lines connected between the suction manifold and each of the compressors. This pick-up means comprises a venturi tube which provides for the flow of oil through each of the suction lines responsive to the flow of refrigerant gas therethrough. The venturi tube has an outlet end positioned in a downstream orientation with respect to the flow of refrigerant gas through a surrounding suction drop sleeve.

Abstract: A single or multiple evaporator vapor-compression refrigerant system for single or multi-story structures includes a lubricating oil collection reservoir and a separate oil pumping unit for returning oil separated from the refrigerant fluid in the refrigerant flow circuit to the compressor unit. In multi-story, direct expansion, vapor-compression, air conditioning systems, a simplified generally vertical refrigerant vapor return riser is provided with an oil reservoir at the lowest elevation point of the riser and a liquid level sensing switch for energizing and deenergizing the separate lubricating oil pumping unit. The pumping unit may include an electric or refrigerant fluid driven motor connected to a pump or the pumping unit may include a pressure vessel into which high pressure refrigerant vapor is admitted to displace oil back to the compressor through an oil return conduit.

Abstract: A recondenser cycles a working volume of cryogen gas through a remote cold box and a coaxial recondensing, heat exchanger transfer line which is inserted into a cryostat. The working volume of gas is compressed to a high pressure and cooled through cooling means which include a mechanical refrigerator of the regenerator-displacer type. The cooled gas is expanded through a first JT valve to a medium pressure and further cooled. The further cooled medium pressure gas is transferred in a closed coaxial transfer line to a cryostat in which boil-off is recondensed. A second JT valve in the cryostat end of an inner tube coaxially positioned in an outer tube forming the transfer line expands the gas to a lower pressure and forms a liquid-gas mixture. The liquid-gas mixture is passed in heat exchange relation with the boil-off from an inner tube to an outer tube of a coaxial recondensing heat exchanger.