A motor operated compressor has a housing having a motor chamber and a driving motor located in the motor chamber. The compressor also has a first scroll and a second scroll coupled to the first scroll to form a compression chamber. A rotating shaft is coupled to a rotor of the driving motor and eccentrically coupled to the first scroll. A rear housing of the motor forms a discharge chamber with the second scroll. A shaft receiving portion that radially supports the rotating shaft is located either in the second scroll or in the rear housing. An oil supply guide flow path located either in the second scroll or in the rear housing connects the discharge chamber and the shaft receiving portion. A decompression member inserted into the oil supply guide flow path, reduces a pressure of a fluid passing through the oil supply guide flow path.

A method of manufacturing a slide of a variable oil pump for a vehicle includes preparing a molded body for a slide of a variable oil pump using prealloy powder including, in percent (%) by weight of the entire composition, 0.45 to 0.55% of carbon (C), 2.8 to 3.2% of chromium (Cr), 0.45 to 0.55% of molybdenum (Mo), 0.35 to 0.5% of manganese (Mn), 0.1 to 0.25% of sulfur (S), and the remainder of iron (Fe) and inevitable impurities. A sintered body is prepared by sintering the molded body. The sintered body is slowly cooled such that a temperature of the sintered body reaches a first temperature range and rapidly cooled when the first temperature range is reached.

A compressor may include a shell, a compression mechanism, a bearing housing, a shroud, a stator, and a rotor. The compression mechanism includes a scroll member that is attached to the shell. The shroud is rotatably fixed relative to the shell and attached to the bearing housing. The stator is fixed relative to the shell. The shroud may have an annular body including an inner surface defining a center shroud passage. The stator may have an outer surface defining a stator passage. An outer surface of the rotor and an inner surface of the stator may be spaced apart and define a discharge gap in fluid communication with the center shroud passage and the stator passage. A continuous passage may extend between a top surface of the scroll member and a bottom surface of the shroud and may be in fluid communication with the shroud passage.

A compound engine system includes a rotary engine with rotating chambers, a compressor section in successive communication with the rotating chambers, and a turbine section in successive communication with the rotating chambers. The turbine section has an output shaft. The output shaft and the engine shaft are drivingly engaged to each other and wherein the turbine section has a power output corresponding to from 20% to 35% of a total power output of the compound engine system. A method of compounding power in a compound engine system is also discussed.

A vacuum pump structure includes a motor, two pump bodies, and a grip. The two pump bodies are connected to the motor and driven by the motor, respectively. Each pump body has a pump chamber with a connection port for connecting a suction pipe. The grip has two ends respectively connected to the two pump bodies for carrying the vacuum pump structure. A communication pipe is disposed inside the grip. The communication pipe is in communication with the pump chambers of the two pump bodies. The two pump bodies jointly perform two working modes at the same time to improve work efficiency.

Techniques involve a motor assembly including a rotor and a stator. The stator includes a contact surface for contacting an outer surface of the rotor. The contact surface includes a rigid material. The motor assembly also includes at least one constraint disposed along a length of the motor assembly, where the constraint constrains a radial and/or tangential movement of the rotor relative to the stator. The at least one constraint may be disposed at one or more proximate ends of the motor assembly, and/or along the length of the motor assembly. The contact surface of the stator may have a profile including peaks and valleys, and in some embodiments, the contact surface may be treated to reduce friction and/or wear.

A screw compressor for a heating, ventilation, and air conditioning (HVAC) system. The screw compressor includes a housing having an inlet end and an outlet end for refrigerant to pass into and out of the housing. A motor is within the housing. A plurality of screw sets are arranged about the motor. The screw sets receive refrigerant entering through the inlet, compress the refrigerant between meshed rotors of the plurality of screw sets, and direct refrigerant out of the housing through the outlet end of the housing.

An electric compressor includes a housing, refrigerant inlet port, a refrigerant outlet port, an inverter section, a motor section, a compression device and a front cover. The housing defines an intake volume and a discharge volume. The refrigerant inlet port is coupled to the housing and is configured to introduce the refrigerant to the intake volume. The compression device is a scroll-type compression device configured to compress the refrigerant. The refrigerant outlet port is coupled to the housing and is configured to allow compressed refrigerant to exit the scroll-type electric compressor from the discharge volume.

Variable displacement pumps and methods of pumping a fluid are provided. An example pump may include a housing having an inlet and an outlet, a rotor fixed for rotation with a shaft, the shaft rotatably mounted within the housing, and a plurality of radially extending vanes slidably disposed in the rotor. The pump may further include a pivotable ring member defining at least in part a control chamber about the rotor, wherein the ring member is pivotable within the housing to vary an eccentricity of the ring member with respect to the rotor. The ring member is configured to shift a pivot position of the ring member from a first pivot position to a second pivot position displaced from the first pivot position.

A non-Wankel rotary engine having an insert in the peripheral wall of the outer body, the insert being made of a material having a greater heat resistance than that of the peripheral wall, having a subchamber defined therein and having an inner surface bordering the cavity, the subchamber communicating with the cavity through at least one opening defined in the inner surface and having a shape forming a reduced cross-section adjacent the opening, a pilot fuel injector having a tip received in the subchamber, an ignition element having a tip received in the subchamber, and a main fuel injector extending through the housing and having a tip communicating with the cavity at a location spaced apart from the insert.