Abstract: A method for detecting compressor or system degradation or malfunction in a multiple circuit compressor system includes the steps of providing a multiple circuit compressor system including at least a first circuit and a second circuit; and comparing a first value corresponding to an operating parameter of the first circuit with a second value corresponding to an operating parameter of the second circuit.

Abstract: In a shell-and-tube heat exchanger with the tubes disposed within the shell for conducting the flow of a fluid to be in heat transfer interaction with a refrigerant contained in the volume formed by the heat exchanger shell and the external surfaces of the tube bundle, the tubes are elongated in their cross-section, with the elongation axis being oriented in the vertical direction to thereby enhance the heat transfer process and potentially reduce the heat exchanger size or tube count. The design features can be applied to both flooded and falling film heat exchangers and are equally applicable to both evaporators and condensers.

Abstract: A refrigerant system is provided where the functions of an economizer heat exchanger and liquid-suction heat exchanger are combined. The two configurations are disclosed with a single common heat exchanger construction. In a first configuration, a series of valves selectively routes only one of two possible refrigerant flows through a common heat exchanger such that a control can selectively activate either an economizer heat exchanger circuit or a liquid-suction heat exchanger function. In a second configuration, both refrigerant flows are passed to the common heat exchanger through separate fluid lines and are selectively activated by the control. Variations of the second configuration are also disclosed.

Abstract: A vapor compression system includes a main vapor compression circuit including a compressor, a condenser, an expansion device and an evaporator serially connected by main refrigerant lines, the compressor having a main discharge port, a suction port and an economizer/bypass port, an economizer circuit connected between the condenser and the economizer/bypass port of the compressor and including an auxiliary expansion device and a heat exchanger serially connected by economizer refrigerant lines, the economizer refrigerant lines and the main refrigerant lines being exposed to each other for heat exchange in the heat exchanger; and a bypass circuit including a bypass line extending from the economizer/bypass port to the suction port, and a bypass valve positioned along the bypass line, the bypass valve being positionable between a closed position wherein the economizer circuit is active and the bypass circuit is inactive, and an open position wherein the economizer circuit is active and the bypass circuit is ac

Abstract: A multiple circuit refrigerant system includes a single economizer heat exchanger utilized for each of at least two circuits. The use of the single economizer heat exchanger reduces the cost of adding an economizer cycle, and further reduces other associated costs. Additionally, heat exchanger and overall system performance is enhanced further. Embodiments show the inclusion of two, three and four circuits, although greater numbers may also benefit form this invention.

Abstract: A vapor compression system includes a first circuit having first components including a first compressor, a first condenser and a first evaporator; a second circuit having second components including a second compressor, a second condenser and a second evaporator; and interconnecting flow lines for selectively communicating the first compressor with at least one component of the second components to boost system performance at part-load operation as well as enhance its reliability and improve unloading capability.

Abstract: The invention provides two distinct schematics allowing system performance enhancement through the utilization of an auxiliary heat exchanger and splitting the refrigerant flow into primary and secondary paths. A system performance boost is achieved due to extra subcooling of a primary refrigerant flow in an auxiliary heat exchanger as well as superheat reduction of the combined refrigerant flow entering the compressor and a primary refrigerant flow pressure drop decrease through the evaporator (in comparison to the prior art). The invention offers the superior benefits outlined above with only a moderate cost increment. Also, employment of conventional components only, and no compressor modifications make implementation of the proposed schematics even more attractive.

Abstract: A method for detecting compressor degradation includes the steps of providing a dataset for a compressor relating compressor operating parameters to each other; detecting real time actual values of the compressor operating parameters including an evaluated operating parameter; using at least one of the real time actual values and the dataset to determine a predicted value of the evaluated operating parameter; and comparing the predicted value of the evaluated operating parameter to the real time actual value of the evaluated operating parameter. This advantageously allows a prognosis of compressor performance to determine whether performance degradation is occurring.

Abstract: An improved apparatus and method for injecting a liquid/vapor into compression chambers at an intermediate pressure utilizes the economizer injection ports already found in the compressor. By selectively communicating a liquid to be injected into the compression chambers to the economizer return line, the economizer return line and its ports are utilized for this liquid/vapor injection. In this way, no additional flow connections at the compressor are necessary. Moreover, by injecting the liquid at an intermediate pressure point, the other benefits are provided. In general, the liquid is injected to reduce the discharge temperature of the refrigerant under certain operational conditions.

Abstract: A refrigeration system for cooling air is disclosed. The system includes a substantially liquid refrigerant and an evaporator for transferring heat from the air to the substantially liquid refrigerant. The substantially liquid refrigerant becomes a low temperature, low pressure first substantially gaseous refrigerant. A compressor compresses the first substantially gaseous refrigerant into a high pressure, high temperature superheated second gaseous refrigerant. A lubricant circuit supplies lubricant to the compressor. A condenser rejects heat from the second gaseous refrigerant and forms a high pressure, lower temperature sub-cooled liquid refrigerant. The condenser has an output stream. A metering device transforms the sub-cooled liquid refrigerant into the substantially liquid refrigerant for the evaporator. A heat exchanger receives the first substantially gaseous refrigerant as a coolant on route to the compressor.

Abstract: A refrigeration system for cooling air s disclosed. The system includes a substantially liquid refrigerant and an evaporator for transferring heat from the air to the substantially liquid refrigerant. The substantially liquid refrigerant becomes a low temperature, low pressure first superheated gas refrigerant. A compressor compresses the first superheated gas refrigerant into a high pressure, high temperature second further superheated gas refrigerant. A lubricant circuit supplies lubricant to the compressor, wherein a portion of the lubricant is mixed with the further superheated gas refrigerant. A condenser rejects heat from the second superheated gas refrigerant and forms a high pressure, low temperature sub-cooled liquid refrigerant. The condenser has an output stream. A metering device transforms the sub-cooled liquid refrigerant into the substantially liquid refrigerant for the evaporator.

Abstract: A 250 watt cryocooler employs a Stirling cycle and is capable of maintaining a constant temperature of 77.degree. K. while fitting a standard electronic equipment rack.

Abstract: A crush tube is used to provide a fluid connection between a first and second member. The crush tube has two tubular portions with a spherical portion therebetween. The tubular portions are loosely received in nominally coaxial bores having entrance chamfers. The spherical portion is deformed into contact with the chamfers as well as between the members whereby the tube provides a sealed fluid path between the bores.

Abstract: A welded bellows is formed by welding together a stack of annular elements such that spacer rings are located between adjacent elements at the inner and outer diameters and are the locations for the welds. The spacer rings eliminate very small clearances/contact between movable members which can be the locations for stress risers in the presence of dirt.

Abstract: A drive shaft having a main bearing portion, formed by metal forging, casting or powdered metallurgy, and having coupled thereto a rotor stub portion comprising a steel tube fixedly secured to the main bearing portion, such as by press fitting, friction or laser welding. The rotor stub portion of the drive shaft contains an insert formed with suitable oil hole passages to deliver oil through the rotor stub portion to any desired location along this portion of the drive shaft.

Abstract: Protection for an encased motor driven device is enhanced by utilizing additional sensors with associated resistance heaters to actuate the thermally responsive contacts of the internal line break. The sensors and heaters are powered from an auxiliary winding in the motor coils. When applied to a hermetic scroll compressor, the compressor can be protected against reverse rotation.

Abstract: Seal structure for a scroll compressor is provided with localized magnetic surfaces. The seal is carried by one member and the magnetic surface coacts with a facing ferromagnetic surface to provide a seal therebetween even when the members are axially displaced and where there is orbiting motion therebetween.

Abstract: The motor protector for a motor is located so as to be responsive to the discharge temperature of a compressor. The protector is thereby responsive to motor current and compressor discharge temperature. Additionally, by conduction, the protector is responsive to the motor temperature. For scroll compressors, specifically, this provides protection from excess heating of the scroll wraps without requiring an additional sensor.

Abstract: The crankshaft and orbiting scroll of a scroll compressor are drivingly connected through a bearing. The bearing is made up of a plurality of roller elements of varying diameters in line contact with both the crankshaft and the orbiting scroll and serving to locate the crankshaft and orbiting scroll eccentrically with respect to each other and thereby provide radial compliancy.