A cooling system for a motor to power a compressor in a vapor compression system is provided. The cooling system includes a housing with a cavity enclosing the motor and defining a central axis and fluid directing features extending into the cavity and oriented parallel to the central axis. The cooling system further includes a fluid circuit configured to circulate a cooling fluid between the housing and the motor. The fluid circuit includes a first cooling fluid path defined by directing features that cause a first portion of cooling fluid to travel around a first portion of the motor and a second cooling fluid path defined by fluid directing features that cause a second portion of cooling fluid to travel around a second portion of the motor. The second portion of the motor is located opposite the first portion.

A structure comprising a rotor body, the rotor body including a rotor shaft arranged on one end face of the rotor body, a sub-shaft cavity opened in the rotor shaft, and locating keyways symmetrically opened on both sides inside the sub-shaft cavity; a sub-shaft arranged on the other end face of the rotor body, and sub-shaft locating keyways symmetrically opened on both sides of the sub-shaft.

Rotary positive displacement machines based on trochoidal geometry, that comprise a helical rotor that undergoes planetary motion within a helical stator are described. The rotor can have a hypotrochoidal cross-section, with the corresponding stator cavity profile being the outer envelope of the rotor as it undergoes planetary motion, or the stator cavity can have an epitrochoidal cross-section with the corresponding rotor profile being the inner envelope of the trochoid as it undergoes planetary motion. In some embodiments, the geometry is offset in a manner that provides structural and/or operational advantages in the rotary machine.

A vane pump or motor assembly includes a housing having an inner cavity with an inner wall disposed about a first central axis. A rotor is disposed in the inner cavity and is rotatable about a second axis that is offset from the first axis to create a variable width space between the rotor and the inner wall. plurality of vanes are moveably carried by the rotor and engage the inner wall to partition the variable width space into a plurality of chambers of increasing and decreasing volume in response to rotating the rotor. Each vane is in the form of a leaf vane having a mounting end formed with a hook portion and wherein the rotor includes corresponding recesses with latch portions that engage of each respective hook portion and supports the leaf vanes for outward swinging movement relative to the rotor for engaging the inner wall of the inner cavity.

One embodiment of a method for operating an internal combustion engine under a pressure less than atmospheric pressure includes the steps of positioning a vacuum pump such that said vacuum pump is in fluid communication with a crankcase of said internal combustion engine, connecting a discharge of said vacuum pump to a separator, wherein a portion of said discharge of said vacuum pump condenses in said separator, connecting a vapor discharge of said separator to a filter, wherein said filter removes a portion of volatile organic compounds from said vapor discharge, and venting said filter to an ambient atmosphere.

A rotor assembly and a compressor are provided. The rotor assembly has a crankshaft, a rotor core, a balance weight and an oil baffle shield. The rotor core is provided with a vent hole. The vent hole extends through the rotor core along an axial direction of the rotor core. The balance weight is located at one end of the rotor core approximate to an oil sump of the compressor. The oil baffle shield is arranged to cover the balance weight and is provided with a central opening. The crankshaft extends through the central opening. An accommodating space is defined between the oil baffle shield and the rotor core. The accommodating space is communicated with the vent hole.

A vane pump includes a rotor having slits, vanes received in the slits, a cam ring having an inner circumference cam face with which the vanes are brought into sliding contact, a side member, pump chambers formed by the rotor, the cam ring, and adjacent vanes, and back pressure chambers formed in the slits by the vanes. In the vane pump, the side member is provided with a back pressure opening portion opening at a sliding-contact surface in sliding contact with the rotor, the back pressure opening portion being configured to communicate with the back pressure chambers, and a protruding opening portion protruding along the rotating direction of the rotor from an end portion of the back pressure opening portion on the communication-finishing side. An inner-side inner circumferential surface of the protruding opening portion is connected to an inner-side inner circumferential surface of the back pressure opening portion.

Method and apparatus for improving the performance, response, and durability of an electro-hydraulic active suspension system. The noise caused by hydraulic flow ripple is reduced and system response is improved.

A fluid pumping system for a vehicle having an internal combustion engine comprises a housing, an electric motor, a rotatable first input adapted to be driven by the internal combustion engine, a rotatable second input driven by the electric motor, and a pump. The pump includes a drum selectively rotated about a drum axis of rotation by one of the first input and the second input, and a pump rotor selectively rotated by the other of the first input and the second input. The drum includes a cam ring having a cavity in receipt of the pump rotor. The drum includes a first fluid inlet port and a second fluid inlet port on opposite sides of the drum such that fluid entering the cavity through the first and second fluid ports flows axially in a direction parallel to the drum axis of rotation. The drum includes a radially extending outlet port such that pumped fluid flows radially out of the cavity. The housing contains the electric motor and the pump.

Provided is a rotor structure of a screw compressor and an inverter screw compressor with the same. The rotor structure includes: a female rotor including a female rotor body, wherein the female rotor body includes a plurality of female teeth, and a tooth profile is formed between tooth crests of two adjacent female teeth of the female rotor body, and the tooth profile is formed by sequentially connecting an arc segment a.sub.1b an envelope bc, an arc segment cd, an arc segment de, an arc segment ea.sub.2, an arc segment a.sub.2a.sub.3 from front to rear along a counterclockwise direction, wherein centers of the arc segment cd and the arc segment de are respectively located on both sides of the tooth profile.