An inner-rotor motor including: an armature assembly including a rotating shaft, an armature unit coupled to the rotating shaft and a pressing unit; a frame assembly including a frame housing the armature unit, a first bearing unit located on one side with respect to the armature unit in an axial direction, and a second bearing unit located on another side with respect to the armature unit in the axial direction; and an urging structure that urges the rotating shaft in a direction away from the second bearing unit and that presses the pressing unit toward the first bearing unit.

A bearing fastening ring used in rotating electrical machines that is able to receive bearings of several diameters when the ring is positioned over a shaft. The bearing fastening ring includes a semi-circular element, scaling profiles of different diameters to accommodate different sizes of bearing, grounding ring apertures in the semi-circular element, cover assemblies extending out from the outer diameter of the semi-circular element, and bracket assemblies extending out from the outer diameter of the semi-circular element.

A power plant for an aircraft such as a UAV with a gas turbine engine that drives an electric generator to produce electrical power. The electric generator is rotatably supported by two foil bearings. A centrifugal compressor is secured to a forward side of the generator rotor shaft. The centrifugal compressor draws in cooling air that flows through the two foil bearings and between a space formed between the rotor coil and the stator coil of the electric generator to provide for cooling of both foil bearings and the coils of the generator.

An actuator comprising a linear electrical machine (LEM) having a stator with a stator bore and a translator axially movable within the stator bore and defining a magnetic circuit airgap therebetween, at least one fluid bearing journal formed on the translator, at least one fluid bearing providing a bearing gap adjacent the translator to allow the translator to move axially within the stator bore, a preload chamber for applying a preload force to the translator, wherein the preload chamber is defined by a side wall, a first end wall and a second end wall at least part of which is movable with the translator, and wherein the bearing gap and the magnetic circuit airgap are coaxial.

Provided is a geared motor with which a large torque can be obtained without an increase in size. In this geared motor (1), an output member (8) having a helical groove (83) formed in an outer circumferential section is provided between a first plate part (31) and a second plate part (32) of a frame (3), and the rotation of a motor pinion (55) fixed to a rotary shaft (50) is reduced in speed by transmission gears of a reduction gear mechanism (9) and is transmitted to a gear part (85) of the output member (8). Thus, a large torque can be output, even when the gear part (85) of the output member (8) is made smaller than the outer diameter of the section (84) provided with the helical groove (83). Also, even when a gear cover (7) is provided, a lateral plate part (72) of the gear cover (7) covering the outer circumferential section of the gear part (85) of the output member (8) is located close to the rotation center axis of the output member (8). Thus, it is possible to prevent the geared motor (1) from being increased in size by the gear cover (7).

A bearing unit includes: an impregnated bearing that rotatably supports a shaft of a rotor; a storage part which is formed in a manner that an end surface of a housing incorporating the rotor in an axial direction becomes convex toward an outer side and which stores the impregnated bearing in a non-rotatable manner; and an oil return washer which is placed to face an end surface of the impregnated bearing stored in the storage part and which integrally rotates with the shaft. The storage part has a bottom tubular shape, and includes an inner surface and a bottom surface, and the oil return washer is placed in a manner that the facing surface overlaps with the inner surface of the storage part when viewed from a radial direction, and includes a circulation part that receives oil leaked from the impregnated bearing and returns the oil to the impregnated bearing.

Certain aspects of the subject matter described here can be implemented in a downhole-type electric submersible pump system. An electric machine can be disposed downhole in a wellbore. The electric machine is coupled to rotate with an impeller that can be disposed downhole in the wellbore. The electric machine includes a stator assembly with at least three stator sections axially arranged and spaced apart from each other along a longitudinal axis of the electric machine. The electric machine also includes a rotor assembly with at least three rotor sections arranged axially along the longitudinal axis of the electric machine. The rotor assembly is carried within and supported to rotate by the stator assembly.

A motor is configured to drive a centrifugal compressor. The motor includes a stator, a rotor, and a shaft. The shaft is supported by a pressure dam bearing (230,240). The pressure dam bearing is lubricated with a lubricant. The lubricant creates a lubricant wedge within the pressure dam bearing that exert an upward force on the shaft. The upward force causes an amount of vibration within the motor. The pressure dam bearing includes a pressure dam (232,242) configured to hold a portion of the lubricant and exert a downward force on the shaft. The downward force balances the upward force and reduces the amount of vibration within the motor, thus achieving greater hydrodynamic stabilization.

The invention relates to a method for producing a rotor unit (10) of an electric motor, in particular a canned motor or the like, for driving a pump wheel of a pump and to a pump, the rotor unit being composed of a rotor (11), a shaft (12), a thrust washer (13) and sliding bearings (14, 15), the rotor being formed by a permanent magnet (22) or a shading coil, the rotor and the thrust washer being attached to the shaft, the shaft being rotatably mounted at one end (16) of the shaft and at the thrust washer by means of respective sliding bearings, the thrust washer being in contact with an axial lateral surface (21) of one of the sliding bearings (14), wherein the shaft is made from a fiber-reinforced polymer material.

A motor may include a rotor comprising a rotating shaft and a bearing component structured to rotatably support. The bearing component may include a sliding surface that the rotor sliding-contacts from a first side in an axial direction. The rotor may include a holding member structured to hold the rotating shaft from an outer circumferential side; a magnet held by the holding member; and a metal component fixed to the rotating shaft and held by the holding member so as to protrude to the outer circumferential side from the rotating shaft.