A motor includes a shaft with a central axis along an up and down direction as a center, a bearing mechanism rotatably supporting the shaft; a cylindrical rotor main body fixed to the shaft; a rotor fan fixed to the shaft at an upper side of the rotor main body; an armature facing the rotor main body in a radial direction; and a housing accommodating the rotor main body, the rotor fan, and the armature therein. The bearing mechanism includes a first bearing above the rotor fan in the housing and facing the rotor fan in the up and down direction and a second bearing positioned below the rotor main body. The housing includes a first opening, a second opening, and a bearing holding portion.

According to an embodiment of the present disclosure, provided is a high-output, high-torque in-wheel motor having a power line-taken-out structure. According to an embodiment of the present disclosure, the in-wheel motor includes a circular rim; a shaft connected to the rim through a center of the rim; a motor assembly including a stator connected to the shaft in the rim and a rotor surrounding the stator and rotated about the stator; a cover coupled to an opening of the rim to block the motor assembly from an outside of the rim; and a bearing contacting and configured to support the shaft. The shaft includes a first shaft body passing through a center of each of the rim and the cover and extending outward; and a second shaft body having a larger diameter than a diameter of the first shaft body and disposed between the stator and the bearing. A power line for supplying power to the motor assembly is inserted in a radial direction of the second shaft body between the stator and the bearing and is taken out in a longitudinal direction of the second shaft body. According to an embodiment of the present disclosure, even when a diameter of the power line is increased to achieve the high-output, high torque performance of the in-wheel motor, structural rigidity of the shaft may not be degraded.

The present disclosure is generally directed to techniques for radial alignment of motor components relative to each other to achieve a motor with a rotor bore having sub-micron end-to-end deviation. In an embodiment, a rotor bore alignment tool is disclosed herein that can be inserted between motor components, and more particularly, apertures/through holes defined by each of the motor components such as housing sections and a stator assembly. The rotor bore alignment tool includes expandable members that can be selectively transitioned to an extended position to cause each of the motor components to be radially aligned prior to securely coupling the same in a so-called “stack” to form a motor. Once the motor components are coupled together, the resulting motor includes a rotor shaft extending from end-to-end that preferably includes a sub-micron deviation of less than 10 microns, and more preferably less than or equal to 5 microns, for example.

A wedge for securing a bearing and a bearing sleeve to an end bell of a rotating electric machine includes an annular base extending about a centerline and having an inner surface defining an opening through the base for receiving the bearing and the bearing sleeve. The base includes opposing first and second ends spaced circumferentially from one another by a gap for allowing relative movement therebetween during securing of the bearing and the bearing sleeve to the end bell.

An oscillating power tool, including: a housing; an output shaft for installing a working head, the output shaft being installed in the housing and extending out of the housing; a transmission mechanism, installed in the housing, and the transmission mechanism being connected to the output shaft; and a motor, installed in the housing, the motor being connected to the transmission mechanism and driving the transmission mechanism to drive the output shaft to move, where an outer diameter of the motor is in a range of 40 mm to 50 mm.

A motor includes a bearing housing, a stator, and a fixing member. The stator includes a stator core, an insulator, and a lead. The insulator is an insulating body that covers at least a portion of the stator core. The lead is wound around the stator core with the insulator interposed therebetween. The bearing housing includes a first bearing holding portion and a second bearing holding portion that hold two bearings; and an intermediate portion that is positioned between the first bearing holding portion and the second bearing holding portion in the vertical direction. The lower surface of the fixing member is in contact with the upper surface of the stator. The fixing member is fixed at a position opposite the intermediate portion in the radial direction. As a result, the displacement of the stator relative to the bearing housing is suppressed.

An electric motor system includes a drive shaft that rotationally drives a load, a bearingless motor, a power source unit, and a control unit. The bearingless motor includes a rotor and a stator having armature and support windings. The bearingless motor rotationally drives the drive shaft and supports a radial load of the drive shaft in a contactless manner. The power source unit applies a voltage to the armature and support windings. The control unit controls the power source unit so that a radial support force that is a sum of a radial support force caused by a support current and a radial support force caused by both the support current and an armature current is output, and so that one of an armature voltage across the armature winding and the support current is increased and the other of the armature voltage and the support current is decreased.

A lead screw device includes: a lead screw; and a motor that rotates the lead screw, wherein the motor includes: a hollow shaft fitted onto a part of an outer circumference of the lead screw; and a rotor core fitted onto a part of the outer circumference of the hollow shaft.

In an electric motor, a magnetic bearing generates an electromagnetic force between multiple permanent magnets and a coil and rotatably supports an other side of a rotation shaft in an axis line direction. The rotation shaft is configured to be capable of being inclined with a rotation center line using a bearing side of the rotation shaft as a fulcrum. An electronic control device controls a current that flows to the coil such that an axis line of the rotation shaft approaches the rotation center line due to a supporting force which is the electromagnetic force between the multiple permanent magnets and the coil. Accordingly, the rotation shaft is rotatably supported to be freely rotatable by a magnetic bearing and the bearing.

Electric motors are disclosed. The motors are preferably for use in an automated vehicle, although any one or more of a variety of motor uses are suitable. The motors include lift, turntable, and locomotion motors.