Abstract: A bearing (20; 150; 152) comprises: an inner race (26); an outer race (28); and a plurality of rolling elements (30). The inner race comprises a nitrogen-alloyed steel (40). The outer race comprises a steel (42) with lower nitrogen content than said nitrogen-alloyed steel.

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 impellers (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. An inlet guide vane (IGV) array (174) is between the suction port (24) and the one or more impellers (44). One or more bearings (66, 68) support the rotor (64) and/or the one or more impellers (44). A purge unit (400) has a vapor inlet line (410) for receiving a refrigerant flow and a return line (414, 417A, 417B) for returning a contaminant-depleted refrigerant flow. A supply flowpath (407A, 407B) for supplying refrigerant to the bearings extends from the purge unit.

Abstract: A fluid damping structure is provided that includes an inner annular element, an outer annular element, a first outer seal, a second outer seal, an inner seal, a damping chamber, a supply plenum, a fill port, and a plurality of fluid passages. The plurality of fluid passages is disposed in at least one of the inner annular element or the inner seal. The fluid damping structure is configured such that one or more of the fluid passages is disposed in an open configuration when a local damping fluid pressure within the damping chamber is less than a local damping fluid pressure in an adjacent region of the supply plenum, and the one or more of the fluid passages is disposed in a closed configuration when the local damping fluid pressure within the damping chamber is greater than the local damping fluid pressure in the adjacent region of the supply plenum.

Abstract: A vapor compression system (20) comprises a compressor (22) having one or more bearing systems (66, 68) supporting a rotor and/or one or more working elements (44). One or more bearing feed passages (114) are coupled to the bearings to pass fluid along a supply flowpath to the bearings. A mechanical pump (130; 330) is positioned to drive fluid along the supply flowpath. An ejector (140, 150) has a motive flow inlet (142, 152) coupled to the mechanical pump to receive refrigerant from the mechanical pump.

Abstract: In one aspect, a refrigeration system is provided. The refrigeration system includes a compressor coupled to a variable frequency drive (VFD), a condenser, an evaporator, an oil separator, and an oil conditioning circuit. The oil conditioning circuit is thermally coupled to the VFD and configured to heat oil from the oil separator with heat produced by the VFD.

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 impellers (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. An inlet guide vane (IGV) array (174) is between the suction port (24) and the one or more impellers (44). One or more bearing systems (66, 68) support the rotor (64) and/or the one or more impellers (44). One or more main drain passages (120, 234 206; 120, 232, 202, 206) are coupled to the bearings to pass fluid along a drain flowpath from the bearings to a location (172) upstream of the impeller and downstream of the IGV array.

Abstract: A fluid damping structure is provided that includes an inner and outer annular elements, first and second ring seals, first and second outer annular seals. The inner annular element has an outer radial surface and a plurality of annular grooves disposed in the outer radial surface. The outer annular element has an inner radial surface. A damping chamber is defined by the inner and outer annular elements, and the first and second inner ring seal. A first lateral chamber is disposed on a first axial side of the damping chamber. A second lateral chamber is disposed on a second axial side of the damping chamber. A plurality of fluid passages are disposed in at least one of the inner annular element or the inner ring seals. The fluid damping structure is configurable in an open configuration and a closed configuration.

Abstract: A fluid damping structure is provided that includes an inner annular element, an outer annular element, a first outer seal, a second outer seal, an inner seal, a damping chamber, a supply plenum, a fill port, and a plurality of fluid passages. The plurality of fluid passages is disposed in at least one of the inner annular element or the inner seal. The fluid damping structure is configured such that one or more of the fluid passages is disposed in an open configuration when a local damping fluid pressure within the damping chamber is less than a local damping fluid pressure in an adjacent region of the supply plenum, and the one or more of the fluid passages is disposed in a closed configuration when the local damping fluid pressure within the damping chamber is greater than the local damping fluid pressure in the adjacent region of the supply plenum.

Abstract: A heat transfer system is disclosed that includes a plurality of electrocaloric elements (12) including an electrocaloric film (14), a first electrode (16) on a first side of the electrocaloric film, and a second electrode (18) on a second side of the electrocaloric film. A fluid flow path (20) is disposed along the plurality of electrocaloric elements, formed by corrugated fluid flow guide elements (19).

Abstract: A heat transfer system includes an electrocaloric element comprising an electrocaloric film (12). A first electrical conductor is disposed on a first side of the electrocaloric film, and a second electrical conductor is disposed on a second side of the electrocaloric film. At least one of the first and second electrical conductors is an electrically conductive liquid. An electric power source (20) is in electrical contact with the first and second electrical conductors, and is configured to provide an electrical field across the electrocaloric film. A liquid flow path (28) is disposed along the plurality of electrocaloric elements for the electrically conductive liquid.

Abstract: Embodiments are directed to simulating an operation of a mechanical lock in an electronic context, comprising: applying a contactless wireless credential to a lock, authenticating the credential, unlocking the lock to provide access to a resource protected by the lock based on having authenticated the credential, determining a security level associated with the lock, and conditionally capturing the credential based on the security level.

Abstract: A system (20; 300) comprises: a vapor compression loop (38; 338); a low-pressure or medium-pressure refrigerant in the loop; a centrifugal compressor (42) along the vapor compression loop and comprising: a housing (120); an inlet (44); an outlet (46); an impeller (140); an electric motor (122) coupled to the impeller to drive rotation of the impeller; and one or more refrigerant-lubricated bearings (130, 132).

Abstract: A heat transfer system is disclosed that includes a circulation loop of a heat transfer fluid that comprises a halocarbon. The circulation loop includes a compressor or pump that includes bearing rolling surfaces in contact with the heat transfer fluid. The bearing contact surface has a substrate a layer thereon that includes a polymer or oligomer having polar side groups and a tribofilm.

Abstract: A vapor compression system (20) has: a centrifugal compressor (22) having an inlet (40) and an outlet (42); and an electric motor (28) having a stator (30) and a rotor (32). A plurality of bearings (36) support the rotor. A refrigerant charge comprises a base refrigerant and one or more oils. The one or more oils are present at a total concentration of 80-5000 parts per million (ppm) by weight.

Abstract: An exemplary fire suppression system includes a sprinkler nozzle. At least one conduit is connected to the nozzle for delivering a fire suppression fluid to the nozzle. The conduit and the nozzle establish a discharge path. A pneumatically driven pump is connected with the conduit for pumping fluid into the conduit. A gas source provides pressurized gas to the pump for driving the pump. The gas source also provides gas to the discharge path for achieving a desired discharge of the fluid from the nozzle.

Abstract: According to one aspect, a lubricant level sensing system for an actuator is provided. The lubricant level sensing system includes a pressure port in an outer housing of the actuator, a pressure sensor, and a pathway from the pressure port to the pressure sensor. The pathway establishes fluid communication between the pressure sensor and a free volume of an internal cavity of the outer housing relative to a lubricant level in the internal cavity such that the pressure sensor detects a pressure of the free volume used to derive the lubricant level.

Abstract: In one aspect, a refrigeration system is provided. The refrigeration system includes a compressor coupled to a variable frequency drive (VFD), a condenser, an evaporator, an oil separator, and an oil conditioning circuit. The oil conditioning circuit is thermally coupled to the VFD and configured to heat oil from the oil separator with heat produced by the VFD.

Abstract: A lock core for a lock assembly is provided including a housing having a first end. An operating member is configured to move between a retracted position and an extended position. When the operating member is in the retracted position, the operating member is at least partially recessed within the housing. A control member is arranged within the housing and is configured to selectively limit movement of the operating member between the retracted position and the extended position. The control member is operably coupled to the controller via an actuator.

Abstract: Embodiments are directed to obtaining a specification comprising at least one requirement associated with a heating, ventilation, and air-conditioning (HVAC) system, and based on the specification, configuring a control system to control a movement of fluid back and forth across at least one regenerator device of the HVAC system and a mixing of the fluid with ambient air.

Abstract: An electromechanical rotary actuator including a housing including first end that extends to a second end through an intermediate portion that defines a longitudinal axis, and an internal cavity. An electric motor is arranged within the internal cavity. The electric motor includes a shaft having first shaft end and a second shaft end. A drive member is arranged within the housing along the longitudinal axis. The drive member includes an input shaft operatively coupled to the first shaft end and an output shaft. An output shaft member is coupled to the output shaft of the drive member. At least one bearing assembly supports one of the output shaft member and the first shaft end, and a preload member is arranged within the housing and configured to apply a compressive axial force to the at least one bearing, the drive member and the electric motor.