Abstract: A combination sight glass and optical sensor is provided in the housing of a hermetic compressor to provide effective visual inspection in addition to automatic sensing of the level of oil in an oil sump. A sight glass fitting is provided in the housing and has a first portion that extends outwardly from the housing and that is accessible from outside the compressor. An optical oil level sensing device is removably attached to the first portion of the sight glass with electrical leads extending outside the compressor for connection to a compressor controller. A prism or similar device is attached to the sight glass fitting intermediate the sump oil and the optical sensor. The sensing device includes a light source, a photosensitive detector, and an opaque member to prevent cross coupling between the light source and the detector.

Abstract: This oil level control device is for a refrigeration system, the control device being attached between the compressor and the oil supply. The control device includes a housing having an inlet communicating with the oil supply and an outlet communicating with a compressor sump; and a solenoid valve controlling flow from the oil supply into the compressor sump. A sensing chamber having a fixed probe providing a proximity detection system detects the oil level in the sump and responds to a change in the complex permittivity of the oil as the oil level rises and falls to generate a signal that controls the supply of oil to maintain the oil level in the compressor. Circuitry is provided having an input connected to the output of the sensor and an output connected to the solenoid valve.

Abstract: A safety pumping system including a pump (19) and an electric motor (15) is adapted to be immersed in a fluid (11) contained in a tank (10). The electric motor and the pump are interconnected by a driving shaft (23). The electric motor is enclosed in a motor housing, which defines an inner space (18). The motor housing is surrounded by an outer shell or jacket (14), which defines an outer space (17) between the outer shell and the motor housing. In order to reduce the risk of explosions when the pumping system is immersed in an inflammable liquid, protective gas, such as nitrogen, at a superatmospheric pressure is supplied to the inner space (18) of the motor housing (15). Protective gas is also supplied to the outer space (17) defined by the outer shell of jacket (14). The gas pressure within the inner space (18) preferably exceeds the gas pressure within the outer space (17), which preferably exceeds the atmospheric pressure.

Abstract: The present invention provides a controller for an air compressor system. The air compressor system includes an air compressor, control unloaders on the air compressor to prevent the air compressor from compressing gases when signaled to unload, an electric motor for driving the air compressor, and a tank for receiving and storing compressed gases from the air compressor. The controller has an adjustable pressure switch to raise or lower the discharge pressure. The differential pressure is pre-set in the pressure switch. The controller includes two methods of operating the air compressor, each of which is manually selected by operating a switch that will designate start/stop control or automatic dual control at the option of the operator. The start/stop control will start the motor when the pressure in the system reaches a predetermined low point. When the preselected high pressure point is reached, a signal is sent to the motor to stop, thereby ending the compressing cycle.

Abstract: A compressor controller provides integrated monitoring, control, and alarm capabilities. The compressor controller receives a run signal from a rack controller. Upon receipt of the run signal, the compressor controller monitors startup conditions to determine whether it is safe to start the compressor. If so, the compressor controller applies power to the compressor and determines whether the compressor is running properly. Once the compressor is running properly, the compressor controller continues to monitor the operation of the compressor. If the compressor controller detects a fault conditions during the startup or operation of the compressor, the compressor controller provides an alarm signal and shuts down the compressor if necessary. The compressor controller provides maximum protection for the compressor by monitoring a plurality of relevant conditions and by shutting the compressor down when necessary.

Abstract: A scroll-type compressor is disclosed which includes both a high pressure lubricant sump and a low pressure lubricant sump. Lubricant from the low pressure lubricant sump is supplied to the various bearing, thrust surfaces and other moving parts to lubricate same and a portion thereof is also supplied to the suction gas entering the compressor to replenish the lubricant in the high pressure sump. An oil separator is disposed in a discharge chamber to separate entrained oil from the compressed gas. A level control assembly is also provided in the discharge chamber and serves to return excessive accumulations of oil from the high pressure sump to the low pressure sump. In one embodiment, the compressor is specifically designed for compression of helium while in a second embodiment, the compressor is adapted for use as an air compressor.

Abstract: A cooling system for an automotive vehicle of the type having a radiator through which a coolant fluid flows includes a fan motor for driving a fan which moves air through the radiator; an alternator for supplying an output voltage to the fan motor; and a voltage regulator which selectively excites the alternator's field winding in response to a control signal, determined on the basis of at least one operational parameter of the vehicle indicative of the cooling requirements of the engine which powers the vehicle to control the output voltage of the alternator, thereby controlling the speed of the fan motor.

Abstract: An optical liquid level sensor for distinguishing between the presence of oil and vapor within a compressor crankcase. The sensor has a light transmitting window positioned to interface the crankcase interior and a planar side facing the crankcase exterior. A light source and a light sensor are both positioned adjacent the exterior face of the window. The sensor has a first condition when the prismatic face is immersed in oil and a second condition when the prismatic face is immersed in vapor. An electronic circuit having a dual MOSFET switch for alternating current is mounted adjacent the light source and sensor. The circuit provides power to the source and monitors the sensor. When the sensor is in the first condition, the circuit closes the switch. When the sensor detects the second condition, the circuit starts a timer and continuously tests the condition of the sensor. If the first condition is detected, the timer resets to its initial value.

Abstract: A system is providing for simultaneously addressing the problems of deadhead pumping, dry pumping, and seal failure in progressive cavity pumps. The system uses a hydraulic channel (23, 25, 26) which runs from the pump's rotor (5) to the pump's hydraulic motor (21) and includes the spaces defined by the seals (17) for the joints (8A, 8B) in the drive line for the rotor (5). At the rotor (5), the system includes a plug (19) which melts at a predetermined temperature. The hydraulic channel (23, 25, 26) is filled with lubricating oil and is pressurized. A drop in pressure either as a result of the melting of the plug (19) or a break in the integrity of the seals (17) is detected and used to stop the operation of the pump's motor (21). The system is resistant to disablement by operators.

Abstract: An integral gas compressor and internal combustion engine. The compressor is built by converting a portion of an internal combustion engine to a compressor by removing the original engine head and valve train and replacing these with a compressor head assembly. The compressor head assembly includes compressor valves and valve chairs for holding the compressor valves in place. An inlet manifold encloses all of the valve chairs and places all of the inlet flow paths through the valve chairs in communication with a gas source. The head defines a discharge passageway therethrough which is in communication with a discharge opening. A venting system is provided to vent any gas that might build up in the compressor due to leakage past the piston rings and to transfer this vented gas to a fuel inlet of the engine, as desired. An oil viscosity sensing system is provided for sensing the oil viscosity in the crankcase and shutting down the engine when the viscosity drops below a prdetermined level.

Abstract: A deep well water pump system has a temperature probe (17) in the air space above the top bearing (12), preferably in the oil inlet chamber (26), and provides means for signalling abnormal temperatures to warning and system shutdown means. A method of detecting bearing overheating indirectly by sensing the shaft temperature and/or the temperature in the enclosed air space above the bearing is disclosed.

Abstract: A refrigeration system is provided with a compressor whose speed is varied to provide load control. In order to prevent compressor damage is lubricating oil pressure sensing control is provided which generates a compressor speed increase signal whenever the oil pressure drops below a predetermined minumum.

Abstract: A thermally protected heater element is located in an oil sump such that it is normally located beneath the surface of the oil whereby the oil is heated and acts as a heat sink relative to the heater element. If the oil level drops below the heater element, the thermal protection disables the heater element and the compressor whereby the location of the heater element defines the nominal minimum oil level.

Abstract: A compressor has a motor and a compressor mechanism connected to the motor. The motor has a coil and is lubricated with lubricant. The compressor mechanism sucks and compresses low-pressure coolant and discharges high-pressure coolant. The compressor comprises a unit for preheating the lubricant, and a unit for detecting line-to-line impedance of the coil of the motor to know the quantity of a mixture of liquified coolant and the lubricant, and controlling activation of the preheating unit and of the compressor according to a result of the detection.

Abstract: A differential pressure sensor indicating a housing forming a high pressure chamber, a nozzle mounted on the housing at one end of the chamber, a diaphragm mounted in the chamber to form a low pressure chamber in the nozzle, a spring retainer in the high pressure chamber, a spindle connected to the diaphragm, a tension spring connecting the spindle to the spring retainer, a circular magnet mounted on the spindle and a transducer mounted on the housing to sense the position of the magnet.

Abstract: The compressor controller includes a timing circuit for timing-out a detected fault in a compressor. Upon the fault existing for longer than a predetermined time limit, the controller removes power from the compressor. If the fault is corrected within the predetermined time limit, even momentarily, the timing process is discontinued and the controller continues to monitor the status of the compressor. The controller also includes a delay timer for delaying the re-energizing of the compressor after an interruption or loss of power occurs. The delay prevents short cycling of the compressor. The controller further includes a status display for indicating compressor functions, connections to an alarm which is initiated in the event of compressor failure, a switch for initiating a self test of the controller, and circuitry for a field applied current sensing relay.

Abstract: Fires caused by the leakage of lubricating oil spraying under pressure from lubricating oil conduits feeding bearings are controlled by stopping the flow of the lubricating oil in response to greater than normal flow of the oil through the conduit and simultaneously shutting down the machine having the bearing to which the oil is fed. A valve mounted in each conduit includes a valve element movable in response to the greater than normal flow through the conduit from a first position, to which it is biased and in which it is spaced from a valve seat, to a second position in which it engages the valve seat. A magnet mounted on the valve element actuates a magnetically operated switch connected in a circuit for shutting down the machine when the valve element moves at least part way from the first position to the second position. An alarm is activated as the machine is being shut down.

Abstract: A pressure sensor probe has a first port connectable to a relatively low pressure source in a compressor crankcase and a second port connectable to a relatively high pressure source at the output of an oil pump. A shuttle is slidably disposed in a bore and has a first end which closes the first port when the difference in pressure between the two ports indicative of normal operation exceeds a selected value determined by the relative areas of the shuttle exposed to the respective pressures and by a coil spring which biases the shuttle away from the first port. A passage is formed between the shuttle and the bore leading from the second port to a force receiving surface on the high pressure side of the shuttle. The length and cross sectional area of the passage is selected to provide a desired dampening or time delay between the high pressure source and the force receiving surface. A control circuit includes a reed switch whose state of actuation is dependent upon the position of the shuttle.

Abstract: A differential pressure operated electrical switch construction is provided and has a housing carrying a pair of rigid terminals and an electrical switch for electrically interconnecting the terminals together under the control of an actuator that is responsive to differential pressure acting across the same. The terminals have free ends angled toward each other and the switch comprises a movable contact member and a spring operatively associated therewith for urging the contact member into bridging contact with the free ends of the terminals to thereby place the terminals in electrical contact with each other.

Abstract: An improved oil pump assembly for a refrigeration compressor is disclosed which includes a sensor located within the oil pump housing which is operative to de-energize the compressor in the event the pressure differential between the inlet and outlet of the oil pump drops below a predetermined level. Pressure sensing communication between the sensor and the inlet is provided via a cutout portion of the gasket between the pump and compressor housing.

Abstract: The lubricant monitoring system comprises an element which absorbs a liquid lubricant on the piston rod between a lubricant wiper assembly surrounding the same and a seal which surrounds the piston rod where the rod enters the compressor cylinder and an electrode of a measuring capacitor (CM) near the element. The lubricant absorbent element acts as the dielectric of the measuring capacitor.In the event of a fault on the lubricant wiper assembly, liquid lubricant is absorbed by the absorbent element so that the dielectric constant changes. This can be utilized for an alarm.

Abstract: A pressure compensator for a submersible pump has features to prevent damage while lowering the pump into the well. The pressure compensator includes a bellows located below the pump. A retainer will mechanically retain the bellows in a position other than its maximum lubricant volume position while lowering the pump assembly into the well. Once the motor begins operation, the retainer will release the bellows for normal movement. The retainer inlcudes a linkage member that is connected to the top of the bellows and extends upwardly to the drive shaft. A latching device latches the linkage member to the drive shaft. A reverse threaded portion in the latching device unscrews the latching device from the linkage member once the motor begins to rotate. A pressure sensing assembly is coupled between the pressure compensator and the motor. A toroidal inductor in the sensing assembly provides a passage for the linkage member.

Abstract: A control system for a compressor utilized in transferring natural gas from relatively low pressure wells to a relatively high pressure pipe line incorporating automatic shutdown of the compressor and automatic restart of the compressor in response to certain conditions with the compressor operating at a desired flow rate regardless of upstream fluctuations in pressure. The compressor is unloaded upon shutdown and remains unloaded for a timed duration after startup thereby reducing the required motor size, compressor wear and also eliminating manual startup for most of the usual causes of gas compressor shutdown, such as low well pressure and high discharge line pressure.

Abstract: A submersible motor pump assembly has a motor which is installed at a level below the pump. The shaft which is driven by the motor and rotates the impeller or impellers of the pump is spacedly surrounded by a tubular member of a thermal barrier in the region between the upper end of the motor housing and the lower end of the pump casing. The solid impurities, especially magnetizable particles, which are circulated by the pump tend to penetrate into the motor housing by way of the clearance between the tubular member and the shaft, and the penetration of such impurities into the motor housing is prevented by an apparatus which conveys a stream of liquid from the discharge nozzle of the pump casing into the clearance and contains a filter with several electromagnets which intercept magnetizable particles and allow a clean stream of flushing liquid to flow into the clearance.

Abstract: A method and apparatus to prevent oil pump cavitation in a hermetically sealed vapor compression refrigeration system are disclosed. A hermetically sealed housing containing the refrigeration compressor transmission and oil supply reservoir is connected to the suction side of the compressor to equalize the pressure in the housing and the suction to the compressor is constructed with a restriction such as an orifice or a venturi to create a pressure drop or is of a size small enough to create a pressure drop when refrigerant flows through the line. The pressure drop is sensed by a pressure differential switch to anticipate sharp drops in pressure in the housing. The flow of refrigerant to the compressor is throttled in response to predetermined pressure drops to prevent a sharp drop in pressure within the transmission housing and thus prevent vigorous boiling of refrigerant from the oil reservoir.

Abstract: A method of regulating startup operation of a vapor compression refrigeration system to prevent oil pump cavitation during startup of the refrigeration system is disclosed. The method comprises monitoring the rate of decrease in evaporator pressure or temperature or monitoring compressor suction line pressure and then comparing this monitored rate to a rate of pressure or temperature decrease which is predetermined to prevent oil pump cavitation. If the monitored rate exceeds the predetermined rate control action is taken to adjust the capacity of the compressor to provide a desired rate of pressure drop which prevents oil pump cavitation. A microprocessor control system and a mechanical control system are disclosed for carrying out the disclosed method.

Abstract: An oil-cooled compressor including a main body driven by a motor for compressing gas and being cooled by oil, an oil tank for removing oil from the gas compressed in the main body and discharged therefrom, and a suction mechanism for supplying oil from the oil tank and gas into the main body. The suction mechanism includes a suction gas throttling mechanism, operable in response to the pressure of the compressed gas discharged from the main body. The motor is controlled by a temperature switch responsive to the temperature of the oil and a pressure switch which is responsive to the pressure of the compressed gas only at a pressure range which is lower than that of the compressed gas actuating the suction gas throttling mechanism.

Abstract: An oil cooled compressor including a compressor member driven by a motor, an oil tank receiving oil therein and removing oil from the gas discharging out of the compressor member, an oil supplying device for supplying the oil in the oil tank into the compressor member, and a pressure responsive control device for controlling the operation of the compressor member. There are provided a first temperature detector detecting the temperature of the oil, a second temperature detector detecting the temperature of the gas, and a temperature responsive control device restricting the function of the pressure responsive control device in response to the temperatures detected by the first and second temperature detectors.

Abstract: A solid state system for controlling a compressor or pump which is driven by a motor, the compressor being loaded or unloaded manually or automatically and proportionally to maintain a selected suction-pressure setpoint and to maintain the load on the drive motor within a motor-current setpoint limit, the system having start-up and shut-down sequences which have timed stages including a delay to permit the building up of oil pressure prior to loading of the compressor and including the automatic loading and unloading of the compressor incident to start-up and shut-down. The control includes monitoring of temperatures and pressures associated with the system and automatic shut-down in response to malfunctions internal to the system, and includes automatic shutdown in response to external malfunctions as selectable options, and further includes separate malfunction indicators with a circuit for providing their operability.

Abstract: A submersible thrust limit switch is mounted between the motor and the pump, thus detecting any predetermined drop in the shaft. Means is provided to shut down the motor and signal upon the opening of the contacts in the switch.