A vacuum pump for pumping a gas includes a pump housing which defines a pump cavity, a shiftable vane, a pump rotor body, a separate axial rotor retaining arrangement, and a radial friction bearing. The pump housing includes a closed housing wall. The pump rotor body includes a vane slit which supports the shiftable vane to define rotating pumping chambers, an axial low-pressure end which is axially supported by the closed housing wall so that a gas pressure inside the pumping chambers is present at the low-pressure end, and an axial high-pressure end. The pump housing is fluidically open at the axial high-pressure end so that atmospheric pressure is present. The axial rotor retaining arrangement includes a retaining sheet body arranged in a transversal plane which axially in part blocks the axial high-pressure end. The radial friction bearing is arranged axially between the vane slit and the axial high-pressure end.

A compressor may include a non-orbiting scroll, an orbiting scroll, a driveshaft and an Oldham coupling. The orbiting scroll meshingly engages the non-orbiting scroll. The driveshaft includes a crankpin engaging the orbiting scroll and driving the orbiting scroll in an orbital path relative to the non-orbiting scroll. The Oldham coupling may include an annular body and a plurality of first keys extending from the annular body and slidably received in slots formed in the orbiting scroll. Each of the first keys may include a first post and a first cap attached to the first post. The first posts may be integrally formed with the annular body from a first material. The first caps may be formed from a second material.

A multi-stage compressor unit including at least a first compressor stage including a first compressor element driven through a first gear-transmission and a second compressor stage including a second compressor element driven through a separate second gear-transmission. The first and second gear transmissions include a driving gear and a driven gear configured to be a multiplier, each of the driven gears is connected to a shaft of a rotor of the first compressor element or second compressor element respectively, where the first motor and the second motor re adapted to drive the first compressor stage and the second compressor stage separately. The gear ratio between the driven gear and the driving gear of either one of the first gear transmission and second gear transmission is situated between two and six.

The present invention provides a co-rotating scroll compressor that can inhibit leakage of lubricant supplied to a synchronous drive mechanism. A co-rotating scroll compressor includes a drive-side plate 20 placed between a driving scroll member 70 and a motor 5 at a predetermined distance from the driving scroll member 70 in a direction of a drive-side rotation axis CL1. The drive-side plate 20 includes a shaft portion 20b fixed to a driving shaft 6 of the motor 5 and a fixing portion 20a fixed to an outer periphery of the driving scroll member 70, and a synchronous drive mechanism made up of a needle bearing 32a and a pin 32b is placed between the drive-side plate 20 and driving scroll member 70.

A compressor may include a non-orbiting scroll, an orbiting scroll, a driveshaft and a bushing. The non-orbiting scroll includes a first end plate having a first spiral wrap extending therefrom. The orbiting scroll includes a second end plate having a first side and a second side. The first side has a second spiral wrap extending therefrom and meshingly engaged with the spiral wrap of the non-orbiting scroll. The second side has a hub extending therefrom. The driveshaft drivingly engaged to the orbiting scroll. The bushing supporting the driveshaft and is disposed within the hub of the orbiting scroll. One of the hub of the orbiting scroll and the bushing includes a convex portion.

A transmission structure of motor connection of roots pump comprises a shaft sleeve, a motor shaft cavity is opened inside the shaft sleeve, and the inner circle of the motor shaft cavity is concentrically meshed with the excircle of the motor shaft; a fixed bolt mounting cavity is opened on the outer surface of the shaft sleeve, a bolt through-hole is opened in the fixed bolt mounting cavity, the shaft sleeve is fixedly connected with the gear seat through a hexagon bolt, and the gear seat and the shaft sleeve rotate synchronously at the same shaft center; a gear is fixedly connected with the gear seat with a bolt, the gear seat is fixed to the pump shaft through a first keyway under the fitting between the first keyway and a first shaft key, and the pump shaft and the motor shaft are coaxially arranged at the center. The utility model overcomes the disadvantages of the prior art, which is convenient to install without wearing parts, not affected by temperature, pressure and external dust; and the structure is simple with compound seal and oil protection function; and when a motor with a motor shaft is selected, only the diameter and keyway of the motor shaft cavity of the part are required to fit the new motor.

Provided is a co-rotating scroll compressor comprising a synchronous drive mechanism that can achieve a long life. The compressor comprises a driving side scroll member (90) driven to rotate about a driving side rotation axis CL1, a driven side scroll member (70) driven to rotate about a driven side rotation axis CL2, a hollowed drive shaft (6) that is connected to the driving side scroll member (90), and driven by a motor (5) to rotate, and a driven shaft (20) that is disposed inside the drive shaft (6), and has one end connected to the drive shaft (6) via a first flexible coupling (21) and the other end connected to the driven side scroll member (70) via a second flexible coupling (22).

A screw compressor is provided with: a compressor body in which a screw rotor is accommodated in a rotor casing; a motor in which a rotator and a stator are accommodated in a motor chamber, the motor for rotationally driving a rotor shaft through use of a motor shaft; axial liquid supplying parts, provided on an anti-rotor side of the motor shaft; a motor shaft cooling part which is a cavity extending in the axial direction inside the motor shaft, the motor shaft cooling part for cooling the motor shaft by circulating a cooling liquid through the inside of the cavity thereof; and a liquid outlet part positioned on a rotor side of the motor shaft or a motor side of the rotor shaft and fluidically connected to the motor shaft cooling part so as to extend radially inward from an outlet opening formed in an outer surface of the motor shaft or the rotor shaft.

A rotary screw compressor includes a compressor assembly and a drive motor assembly. The compressor assembly includes a compressor housing, a first screw rotor and a second screw rotor installed in the compressor housing and engaged with each other. An end of the first screw rotor is an engaging end. The drive motor assembly includes a motor housing, a motor rotor, a motor stator and a centering bushing installed in the motor housing, and the motor stator installed on an outer side of the motor rotor and capable of driving the motor rotor to rotate, and the centering bushing is passed and connected to the inner circumference of the motor rotor and has an end sheathed on the engaging end, so that the motor rotor can drive the first screw rotor to rotate through the centering bushing and the engaging end.

A compressor is provided that may include a drive shaft, a compression mechanism, a bearing and an unloader. The drive shaft may include a main body and a crank pin extending from the main body. The compression mechanism may include first and second members. The crank pin may drivingly engage the second member and cause motion of the second member relative to the first member. The bearing may rotatably supporting the main body of the drive shaft. The unloader may rotatably engage the bearing and slidably engage the main body.