Abstract: A compressor, as well as a lightweight and strong casting for a compressor, are disclosed. The compressor, which may be a reciprocating compressor for use in compressing high-pressure refrigerants such as CO2, includes substantially reduced wall thicknesses (t) compared to prior art castings. The side walls of the compressor can be manufactured to such reduced thicknesses (t) through the use of a bridge spanning across the crankcase. This not only allows the opposing side walls to be manufactured of a thinner material, but the bottom cover removably mounted to the crankcase can be manufactured from a thinner and lighter material as well. Through the use of such a bridge, the resulting compressor is not only able to satisfy current strength requirements, but at significant weight, size and cost savings as well.

Abstract: A compressor (22) has a housing assembly (50) with a suction port (24) and a discharge port (26). An impeller (54) is supported by a shaft (70) which is mounted for rotation to be driven in at least a first condition so as to draw fluid in through the suction port (24) and discharge the fluid from the discharge port (26). A magnetic bearing system (66, 67, 68) supports the shaft (70). A controller (84) is coupled to an axial position sensor (80) and is configured to control impeller position.

Abstract: A compressor (22; 260; 300; 400) has a housing assembly (140) with a suction port (24), a discharge port (26), and an economizer port (58). An impeller (154) is mounted to be driven in at least a first condition so as to draw a main flow of fluid through the suction port and discharge the fluid from the discharge port. A diffuser (220; 302; 402) has a plurality of diffuser passages (222; 310, 308; 403). Each diffuser passage has an inlet (224) positioned to receive fluid from the impeller and an outlet (220) downstream of the inlet in the first condition. One or more passages (230, 231, 232, 234, 236, 268; 320, 330, 332; 412) are positioned to draw an economizer flow of fluid from the economizer port and deliver the economizer flow downstream of the impeller inlet (212) but upstream of the diffuser passage outlets (226).

Abstract: A heat exchanger is provided and includes a shell extending between opposing tube sheets to define an interior, nozzles coupled to the shell by which a first fluid is communicated with the interior and a tubular body extending between the opposing tube sheets to transmit a second fluid through the interior whereby heat transfer occurs between the first and second fluids along a heat transfer portion of the tubular body defined from respective planes of opposing faces of the opposing tube sheets, the heat transfer portion having at least first and second topologies at first and second sections thereof, respectively, which are respectively disposed proximate to the respective planes of the opposing faces of the opposing tube sheets.

Abstract: A compressor (22) has a housing assembly (40) with a suction port (24), a discharge port (26), and a motor compartment (60). An electric motor (42) has a stator (62) within the motor compartment and a rotor (64) within the stator. The rotor is mounted for rotation about a rotor axis (500). One or more working elements (44) are coupled to the rotor to be driven by the rotor in at least a first condition so as to draw fluid in through the suction port and discharge the fluid from the discharge port. A gap (80) is between the rotor and stator. The gap is isolated (140, 142) from an outer portion (144) of the motor compartment. The outer portion is exposed to the stator. One or more passages (150) are positioned to draw fluid from the gap in the first condition.

Abstract: An apparatus (20) has a centrifugal compressor (24), a positive displacement compressor (26), a first heat exchanger (32), and a second heat exchanger (36). A plurality of valves (70, 72, 74) are positioned to provide operation in at least two modes. In a first mode, refrigerant is compressed in the positive displacement compressor and the centrifugal compressor at least partially in parallel. In a second mode, refrigerant is compressed in the positive displacement compressor and the centrifugal compressor is offline. In a third mode, refrigerant is compressed in the positive displacement compressor and the centrifugal compressor at least partially in series.

Abstract: A compressor (22) has a housing assembly (50) with a suction port (24) and a discharge port (26). A shaft (70) is mounted for rotation about an axis (500) and an impeller (44) is mounted to the shaft to be driven in at least a first condition so as to draw fluid in through the suction port and discharge the fluid from the discharge port. A magnetic bearing system (66, 67, 68) supports the shaft. A controller (84) is coupled to a sensor (80, 82) and configured to detect at least one of surge and pre-surge rotating stall and, responsive to said detection, take action to prevent or counter surge.

Abstract: A compressor has first and second enmeshed rotors rotating about first and second axes to pump refrigerant to a discharge plenum. The compressor includes a muffler system comprising a sound absorbing first element and a sound absorbing second element. The second element at least partially surrounds the first element and defines a generally annular flow path portion between the first element and the second element At least one of the first and second elements comprises an expanded bead material.

Abstract: A compressor system having a centrifugal compressor, controller and an interface is disclosed. The compressor includes adjustable guide vanes and a variable geometry diffuser. The controller is in electrical communication with each of the guide vanes and diffuser so as to monitor and adjust positions thereof in accordance with a predetermined control algorithm. The control algorithm is implemented in accordance with a method of controlling the centrifugal compressor. The method adjusts the position of the diffuser based on the actual lift, guide vane position and predetermined relationships between diffuser position and reference lift.

Abstract: A compressor, as well as a lightweight and strong casting for a compressor, are disclosed. The compressor, which may be a reciprocating compressor for use in compressing high-pressure refrigerants such as CO2, includes substantially reduced wall thicknesses (t) compared to prior art castings. The side walls of the compressor can be manufactured to such reduced thicknesses (t) through the use of a bridge spanning across the crankcase. This not only allows the opposing side walls to be manufactured of a thinner material, but the bottom cover removably mounted to the crankcase can be manufactured from a thinner and lighter material as well. Through the use of such a bridge, the resulting compressor is not only able to satisfy current strength requirements, but at significant weight, size and cost savings as well.

Abstract: A vapor compression system includes a compressor, a condenser, an expansion device and an evaporator. Refrigerant circulates though the closed circuit vapor compression system. Touchdown bearings protect a rotor during power shutdown of the compressor. Liquid refrigerant from the condenser flows along a supply line and lubricates the touchdown bearings. The refrigerant from the touchdown bearings is discharged through an outlet and flows along a discharge line to the evaporator.

Abstract: A compressor has first and second enmeshed rotors: rotating about first and second axes. The first rotor is supported by a bearing system carried by a bearing case. The bearing case has at least a first port to a discharge plenum. A first sound-absorbing material is positioned within the first port.

Abstract: A screw compressor for use in a chiller assembly includes cooperating screw rotors configured to increase the pressure of a vaporized refrigerant flowing through the compressor, a venturi tube arranged in a flow path of the refrigerant in the compressor downstream of the rotors, and an inlet port in fluid communication with a throat of the venturi tube and configured to deliver liquid refrigerant from a condenser of the chiller assembly to the flow path of the refrigerant in the compressor. The venturi tube is configured to cause a pressure drop in the refrigerant in the compressor. The liquid refrigerant delivered from the condenser reduces pulsations in the pressure of the refrigerant discharged from the compressor.

Abstract: A compressor is powered by a motor which is, in turn, powered by a variable speed drive (VSD). The switching frequency and voltage/frequency relationship of the VSD may be adjusted dynamically to maximize efficiency.

Abstract: A compressor has first and second enmeshed rotors rotating about first and second axes to pump refrigerant to a discharge plenum. The compressor includes a muffler system comprising a sound absorbing first element and a sound absorbing second element. The second element at least partially surrounds the first element and defines a generally annular flow path portion between the first element and the second element At least one of the first and second elements comprises an expanded bead material.

Abstract: A compressor has first and second enmeshed rotors: rotating about first and second axes. The first rotor is supported by a bearing system carried by a bearing case. The bearing case has at least a first port to a discharge plenum. A first sound-absorbing material is positioned within the first port.

Abstract: A vapor compression system includes a compressor, a condenser, an expansion device and an evaporator. Refrigerant circulates though the closed circuit vapor compression system. Touchdown bearings protect a rotor during power shutdown of the compressor. Liquid refrigerant from the condenser flows along a supply line and lubricates the touchdown bearings. The refrigerant from the touchdown bearings is discharged through an outlet and flows along a discharge line to the evaporator.

Abstract: A compressor is powered by a motor which is, in turn, powered by a variable speed drive (VSD). The switching frequency and voltage/frequency relationship of the VSD may be adjusted dynamically to maximize efficiency.

Abstract: A muffler assembly, comprising an outer muffler assembly comprising a plurality of fiberglass discs and a plurality of reactive plates, and an inner muffler assembly comprising a plurality of fiberglass discs and a plurality of reactive plates the inner muffler assembly generally surrounded by the outer muffler assembly and defining therebetween a gas flow gap.

Abstract: A baffle for use in a refrigerator apparatus comprises a baffle plate comprising a first and a second opposing sides attached to an inner surface of the refrigerator apparatus, a baffle seal plate attached along a third side of the baffle plate, the baffle plate seal plate attached to the inner surface of the refrigerator apparatus.