Methods and systems for detecting and correcting improper operation of a compressor in a refrigeration system and/or an HVAC system include a component level detection and prevention and a system level detection and prevention. The system level detection and prevention can be a backup or a confirmation of the component level detection and prevention. The component level detection and prevention can detect and prevent improper compressor operation within a predetermined time so that the compressor's operation period in an improper direction can be minimized, thereby minimizing wear and damage to the compressor.

A scroll compressor includes a fixed scroll fixed inside a housing, an orbiting scroll configured to orbit engaged with the fixed scroll, a rotary shaft configured to allow the orbiting scroll to orbit by supporting the orbiting scroll with an eccentric shaft eccentric from a main shaft, and a slide bush portion installed between a bearing of the orbiting scroll and the eccentric shaft and according to a rotational speed of the rotary shaft, configured to change a pressing force of the orbiting scroll applied to the fixed scroll by allowing an eccentricity to be changed by a gas load applied to the orbiting scroll.

A compressor having a torque load reducing unit to move a center of weight to which a gas force is applied is provided. As the torque load reducing unit is formed at an oval-shaped roller, a distance between a rotation center of the roller and an operation point to which a gas force is applied is shortened. This may reduce a torque load to the roller, and may enhance a compression efficiency.

Exhaust gas recirculation pump (30) for an internal combustion engine that includes an electric motor (32) disposed within a housing (36). A Roots device (38) is coupled to the electric motor (32) and includes a housing (40) defining an internal volume (42) in which rotors (44) are disposed and are connected to the electric motor (32). The electric motor housing (36) includes a coolant path (48) formed therein which extends from a coolant inlet (58) to a coolant outlet (78), both coupled to an engine coolant circulation system. The housing includes an oil path (108) formed therein. The oil path includes an oil inlet (110) extending to at least one oil outlet (112). The oil inlet and outlet are coupled to an engine oil circulation system wherein the oil path (108) lubricates bearings (100) and a transmission assembly (46) of the exhaust gas recirculation pump (30).

A method of operating an exhaust gas recirculation pump for an internal combustion engine including: providing an EGR pump assembly including an electric motor coupled to a roots device having rotors, the EGR pump operably connected to an internal combustion engine; providing an EGR control unit lined to the EGR pump assembly; providing sensors linked to the EGR control unit; determining if a motor speed is within a predetermined target (step SI), wherein when the motor speed is within the predetermined target then; determining if a motor torque is within a predetermined target (step S2) wherein when the motor torque is within the predetermined target then; determining if a motor temperature is within a predetermined target (step S3) wherein when the motor temperature is within the predetermined target then; maintaining operation of the exhaust gas recirculation pump.

A spiral valve and a screw compressor having a compressor housing and the spiral valve are provided. The spiral valve includes an actuator module disposed adjacent an exterior of the compressor housing, the actuator module includes an electric motor, a gearbox mechanically coupled to the electric motor to transmit torque from the electric motor, a shutter coupled to the gearbox to rotate in response to a transmitted torque from the electric motor, wherein the shutter is positioned to open and close one or more of a plurality of bypass ports formed in the compressor housing based on the rotational position of the shutter, wherein the compression length of the screw compressor may be controlled by controlling the opening and closing of the one or more bypass ports.

A linear actuator system includes a linear actuator and at least one proportional control valve and at least one pump connected to the linear actuator to provide fluid to operate the linear actuator. The at least one pump includes at least one fluid driver having a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from the pump inlet to the pump outlet. The linear actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover and concurrently establishes an opening of the at least one proportional control valve to adjust at least one of a flow and a pressure in the linear actuator system to an operational set point.

This disclosure is directed to systems and methods for controlling compressor motors, particularly varying the operation parameters of the motor to provide heat to a lubricant of the motor. The operation parameters include one or more of a pulse width modulation switching frequency, a pulse width modulation frequency switching pattern, or a torque/amp ratio of a drive of the compressor. The efficiency of the motor may be reduced to provide heat, with the heat improving lubricant quality and drive efficiency, to increase an overall efficiency of compressor operations. Methods may include determining a lubricant quality, and determining operational parameters that improve lubricant quality.

Methods and systems for detecting and correcting improper operation of a compressor in a refrigeration system and/or an HVAC system include a component level detection and prevention and a system level detection and prevention. The system level detection and prevention can be a backup or a confirmation of the component level detection and prevention. The component level detection and prevention can detect and prevent improper compressor operation within a predetermined time so that the compressor's operation period in an improper direction can be minimized, thereby minimizing wear and damage to the compressor.

A linear actuator system includes a linear actuator and at least one proportional control valve and at least one pump connected to the linear actuator to provide fluid to operate the linear actuator. The at least one pump includes at least one fluid driver having a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from the pump inlet to the pump outlet. The linear actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover and concurrently establishes an opening of the at least one proportional control valve to adjust at least one of a flow and a pressure in the linear actuator system to an operational set point.