Abstract: A refrigerant handling system that includes a compressor and a condenser, each having an inlet and an outlet, with the condenser inlet normally being connected to the compressor outlet so that refrigerant in vapor phase from the compressor is at least partially condensed in the condenser. To clear liquid refrigerant from the condenser, the compressor outlet is disconnected from the condenser and connected to a refrigerant storage container, and the condenser outlet is connected to the compressor inlet. The compressor is then operated to draw refrigerant in vapor phase from the condenser, and to feed such refrigerant to the refrigerant storage container bypassing the condenser. A gauge is coupled to the compressor inlet so that compressor operation may be terminated by the operator when refrigerant vapor pressure in the condenser drops below a preselected threshold level. Thus, the condenser is cleared of refrigerant, which is now stored in the refrigerant storage container.

Abstract: A system for servicing refrigeration equipment having at least one service fitting of first predetermined configuration includes devices for recovering, purifying and/or recharging refrigerant within such equipment. A manifold includes a first refrigerant hose or conduit having an end coupling for releasable connection to the service fitting of the equipment under service and a second refrigerant hose or conduit having an end coupling for selective releasable connection to service fittings on each of the refrigerant service devices. Each of the first and second couplings includes facility for automatically sealing the associated conduit upon disconnection from the fittings, and thereby sealingly retaining refrigerant within the conduits.

Abstract: A refrigerant handling system in accordance with the present invention includes a closed liquid refrigerant storage container and a pump for feeding refrigerant in liquid phase to the container so that any air carried by the circulating refrigerant is captured in the container over the refrigerant. A differential pressure gauge has a first input that receives a fluid pressure signal which varies as a function of saturation pressure of refrigerant in liquid phase fed to the container, and a second input that receives an associated fluid pressure signal as a function of air pressure within the closed container volume. An indicator dial on the gauge displays pressure differential between the refrigerant saturation pressure and the container vapor pressure at the first and second gauge inputs for observation by an operator. A valve is coupled to the container for venting air from the container when such pressure differential exceeds a preselected threshold.

Abstract: An electronic scale assembly for transferring refrigerant charge between a tank and refrigeration equipment under service comprises a generally rectangular enclosure that includes a handle positioned along one side edge of the enclosure for manually transporting the scale, and a cover for selectively opening and closing the enclosure. A scale includes a platform mounted within the enclosure at a position to support a refrigerant tank when the cover is open, and a strain gage sensor for providing an electrical signal as function of weight supported by the platform. A solenoid-operated refrigerant transfer valve is mounted within the enclosure for connection between a tank mounted on the scale platform and refrigeration equipment under service for selectively transferring refrigerant between the tank and the equipment through the valve. An electronic controller is responsive to the electrical scale signal for indicating weight of refrigerant transferred through the valve.

Abstract: A refrigerant handling system that includes a compressor having an inlet and an outlet, a condenser for withdrawing heat from and at least partially condensing refrigerant passing therethrough, and a compressor oil separator connected between the compressor outlet and the condenser for separating oil from refrigerant passing to the condenser. The compressor oil separator takes the form of a closed canister having an open internal volume, a vapor inlet and a vapor outlet at an upper portion of the canister, and an oil drain at a lower portion of the canister. A refrigerant coil is mounted externally of the canister in heat exchange relationship with the canister sidewall. The vapor inlet, vapor outlet and refrigerant coil are connected in series between the compressor outlet and the condenser coil such that heat of refrigerant passing through the coil heats the canister internal volume to prevent condensation of refrigerant therein.

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 refrigeant 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 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 system for purification of refrigerant within a storage container includes a filter/dryer for removing contaminants' from refrigerant passing therethrough, and a refrigerant pump connected to the storage container to circulate refrigerant in a closed path from the container through the filter/dryer and return the refrigerant to the container. The system configuration is such that the refrigerant is in liquid phase in at least a portion of the closed path. A pressure-differential valve has an inlet coupled to a purge port on the container for receiving air captured within the container. Container air pressure at the valve inlet is fed to one side of a flexible diaphragm. Circulating liquid refrigerant is passed in heat transfer contact with a sealed enclosure containing liquid refrigerant, so that the refrigerant within the enclosure is at saturation pressure and acts on the opposing side of the diaphragm in conjunction with a valve spring.

Abstract: A system for servicing refrigeration equipment having at least one service fitting of first predetermine configuration includes devices for recovering, purifying and/or recharging refrigerant within such equipment. A manifold includes a first refrigerant hose or conduit having an end coupling for releasable connection to the service fitting of the equipment under service and a second refrigerant hose or conduit having an end coupling for selective releasable connection to service fittings on each of the refrigerant service devices. Each of the first and second couplings includes facility for automatically sealing the associated conduit upon disconnection from the fittings, and thereby sealingly retaining refrigerant within the conduits.

Abstract: A refrigerant recovery system that includes a compressor having a inlet connected to a refrigeration system from which refrigerant is to be recovered, and an outlet connected through a condenser to a refrigerant storage container. The condenser includes multiple condenser sections, preferably in an integral assembly having parallel independant refrigerant flow paths. Valves alternately and selectively connect the compressor outlet through the several condenser sections to corresponding storage containers, such that differing refrigerants are fed to associated containers through correponding condenser sections without substantial intermixing or contamination.

Abstract: A method and apparatus for dispensing a foam product, wherein an elastomeric base material, which is solid at ambient temperatures, and a liquid material are combined to form a foam product, comprising heating the base material to melt the material, heating the liquid material to maintain the liquid at an elevated temperature above ambient, metering simultaneously portions of the base material and liquid material, mixing the portions, thereafter heat conditioning the mixture at a temperature above the melting temperature of the base material, subsequently conditioning the mixture to a lower temperature below that of the melting temperature of the base material and finally elevating the temperature of the mixture to about the melting temperature of the base material to provide a product suitable for use as a sealant such as a gasket. The temperatures and pressures of the materials throughout the dispensing are controlled thereby producing a uniformly consistent and repetitively formed foam product.

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: Hand-held apparatus for detecting presence of halogen refrigerant agents in air in which a pair of ultrasonic transducers are spaced from each other within a measurement probe and test air is continuously drawn between the transducers by a fan. One transducer is energized at constant ultrasonic frequency, and the other transducer is coupled to a rectifier or a phase detector for providing a measurement signal as a function of radiation received at and reflected by such other transducer. A reference signal level is established by selectively sampling and electronically storing of the measurement signal, such that the reference level is automatically or manually updated to reflect changes in ambient conditions. An audio/visual alarm is activated when the measurement signal departs from the ambient reference level by more than a preselected threshold.

Abstract: A refrigerant recovery system that includes a refrigerant storage container, means for withdrawing refrigerant from a refrigeration system to be serviced and feeding such refrigerant to the container for storage, and a scale supporting the container for sensing impending overfill of the container. The scale includes a beam horizontally rigidly cantilevered from a base. A switch is positioned adjacent to the cantilever-remote end of the beam, and is responsive to deflection of the beam to indicate impending overfill of the container and prevent or terminate operation of the refrigerant recovery system.

Abstract: Apparatus for precision tensioning of threaded fasteners and the like comprising a drive head having a shaft for applying turning torque to a threaded fastener, a strain gage mounted on the drive shaft for providing a torque signal as a function of torque applied to the fastener, and an optical encoder for providing an angle signal as a function of angle of rotation of the fastener. An electronics package includes a microprocessor-based controller, an alphanumeric display for displaying either torque or angle as well as additional operating mode information, and a membrane switch panel for operator selection of angle-monitoring mode, torque-monitoring mode, measurement or setup operating modes, torque display in Newton-meters or foot-pounds, and for programming desired torque and/or angle thresholds into the control microprocessor.

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 system for recovering, purifying and recharging refrigerant in a refrigeration system comprises a refrigerant compressor having an input connected through an evaporator and a recovery control valve to a refrigeration system from which refrigerant is to be recovered, purified and recharged. A condenser is connected to the output of the compressor in heat exchange relation with the evaporator for liquifying refrigerant from the compressor output. Refrigerant liquified in the condenser is fed to a first port of a refrigerant storage container. During a purification cycle, refrigerant is circulated from a second port of the refrigerant storage container in a closed path through a circulation valve and a filter for removing water and other contaminants, and then returned to the first container port. The refrigeration system from which refrigerant has been recovered is evacuated to atmosphere through a vacuum valve.

Abstract: Apparatus for analyzing air conditioning systems comprising a temperature probe adapted for manual placement at each of a plurality of preselected points in turn around the refrigerant loop to provide signals indicative of temperature at each point. Apparatus electronics are coupled by a cable to the temperature probe and includes facility for reading and storing each of the probe temperature measurements in turn. Information indicative of standards and ranges of temperature data for properly operating refrigeration systems of a number of models and manufacturers is prestored in apparatus memory. The system temperature readings are compared to each other and to the prestored data to diagnose a plurality of fault conditions and to display diagnosed fault conditions to an operator.

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: Apparatus for service and recharge of refrigeration equipment, with particular application to automotive air conditioning equipment. A vacuum pump, and oil and refrigerant charge containers are housed within a portable enclosure and configured for selective connection by electrically operated solenoid valves to refrigeration equipment under service. The refrigerant and oil containers are carried by a scale which provides electrical outputs signals as a function of weight of refrigerant and oil remaining in the containers. A microprocessor-based controller receives the scale signals and control signals from an operator panel for automatically cycling through vacuum, oil charge and refrigerant charge stages in a programmed mode of operation. The microprocessor-based controller includes facility for operator programming of the vacuum time and oil and refrigerant charge quantities, and for self- or operator-implemented diagnostics. Operating conditions and stages are displayed at all times to the operator.