A motor assembly includes a rolling bearing installed on a rotation shaft between an impeller and a rotor to support a first support of the rotation shaft, and a motor housing having a stator. The motor housing has a gas bearing bracket for accommodating a second support of the rotation shaft disposed at a side opposite to the first support with respect to the rotor. The motor assembly includes a gas bearing assembly in the gas bearing bracket to support rotation of the second support of the rotation shaft. The gas bearing assembly includes a gas bearing for surrounding the second support. The gas bearing is spaced apart from the second support of the rotation shaft to define a gap therebetween when the rotation shaft rotates. The gas bearing assembly includes an elastic member interposed between the gas bearing bracket and the gas bearing to elastically support the gas bearing.

One aspect of an electric actuator of the present invention includes: a motor having a motor shaft rotatable about a motor axis; a transmission mechanism coupled to one side in the axial direction of the motor shaft; an output shaft extending in the axial direction of the motor shaft and to which rotation of the motor shaft is transmitted via the transmission mechanism; and a rolling member group including three or more rolling members arranged to surround the motor axis. The motor shaft is a hollow shaft. At least a part of the output shaft is located inside the motor shaft. The motor shaft and the output shaft are supported with each other in the axial direction and the radial direction via the rolling member group.

An electric submersible pump assembly with integral heat exchanger, high speed gas separator, high-speed self-aligning bearings, and dual bearing thrust chamber is described. The described gas separator may be used for operating an electric submersible pump at high speeds as well as over a wide range of speeds and flowrates without replacing downhole equipment.

A tool includes a device including a housing and a rotor, the rotor to rotate about a longitudinal axis, and an axial gap generator including a stator assembly positioned adjacent to the rotor. The axial gap generator generates a voltage signal as a function of a gap spacing between the stator assembly and the rotor, the gap spacing being parallel to the longitudinal axis.

A compressor or pump stage is provided. The compressor or pump stage at least comprising a central shaft (8) and one rotor (3), where the axis of rotation of the rotor (3) is the central shaft (8) and where the rotor comprises a number, n, of rows of impellers (5) arranged at an outer perimeter of the rotor with an axial distance between neighbouring rows of impellers (5), where n={2, 3, 4 . . . }.

An electric motor contains a motor shaft which is arranged in a motor housing. The motor shaft is rotatably mounted about a rotational axis in at least one rolling or ball bearing, which sits in a bearing receiving area and contains an outer ring and an inner ring fixed to the motor shaft. The outer ring of the rolling bearing is pretensioned by a spring disc which sits in the bearing receiving area and has a number of wave trains with alternatingly axially projecting half wave trains, and the spring disc has a number of centering elements on the inner circumference. The centering elements rest against the motor shaft when the spring disc is untensioned and is arranged at a distance to the motor shaft when the spring disc is tensioned.

A rotor, which includes a rotor main body and a fan. The rotor main body includes a rotor core, a rotary shaft extending through the rotor core, and a permanent magnet mounted in the rotor core. The fan includes a plurality of fixing portions embedded in the rotor main body and configured to fix the permanent magnet. The rotor has a simple structure, can be easily assembled, and has a low cost.

An electric centrifugal pump having a motor housing, a pump head, a containment shell, and a rotor assembly consisting of a pump impeller and a permanent magnet rotor, wherein the pump head with the containment shell defines a wet chamber, in which the rotor assembly is arranged rotationally around a longitudinal motor axis, the containment shell with the motor housing defines a dry chamber, in which a wound stator is arranged, and the permanent magnet rotor is arranged within the stator and a hollow-cylindrical region of the containment shell. Particle accumulations in the region between the containment shell and the permanent magnet rotor cannot occur or can only occur to a very minor extent and that the consequences of impurities in the wet chamber are reduced in order to prevent premature wear or a blockage of the centrifugal pump.

A high-speed permanent magnetic motor assembly generates a magnetic field to produce mechanical output power. The assembly comprises a motor, a motor housing, and a radial bearing block. A motor housing supports a rotor and the radial bearing block with a left radial aerostatic bearing, a right aerostatic bearing, and an axial thrust aerostatic bearing. The bearings are porous aerostatic bearings that use a low-viscous vapor-liquid two-phase fluid as a lubricant, which penetrates through a porous bushing. The liquid vaporizes from pressure reduction, and part of the liquid arrives at a clearance between each of the bearings and the rotor. The liquid of the two-phase fluid is vaporized during discharge along an axial direction from the bearing. This increases the vapor in the clearance, improve a bearing capacity, retain position accuracy of an aerostatic bearing, and cool the aerostatic bearings and the rotor.

A compressor includes a rotor configured to compress air and driven by a shaft. A motor is drives the shaft. The first and second journal bearings facilitate rotation of the shaft. The first journal bearing is upstream from the motor and the second journal bearing is downstream from the motor. The transfer tube is configured to provide cooling air from a bearing cooling air inlet to the first journal bearing. A method for cooling a compressor is also disclosed.