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.

An electric work machine, such as a lawn mower includes a motor case (22) fixed inside a main-body housing (10). A brushless motor (21) is housed inside the motor case (22) and includes a stator (23) having a stator core (40), coils (45), and upper and lower insulators (42, 43), and a rotor (24) disposed inward of the stator (23) and having a rotary shaft (25). A spindle (17) is driven by the rotary shaft (25). The motor case (22) holds the stator (23) and axially supports the rotary shaft (25) via bearings (68, 76). One or more insulating members, such as an insulating cap (67) and/or a resin layer (78), provide electrical insulation between the stator core (40) and the rotary shaft (25).

The present disclosure provides a stator core, a magnetic levitation bearing, and a motor. The stator core is used in the magnetic levitation bearing and includes an annual yoke. The annular yoke has an inner circumferential wall and an outer circumferential wall, a plurality of pole pillars are disposed on the inner circumferential wall, and each of the plurality of pole pillars extends towards an axis of the inner circumferential wall, there is a distance D between an axis of the outer circumferential wall and the axis of the inner circumferential wall, and D≠0 is satisfied. According to the stator core, the magnetic levitation bearing, and the motor of the present disclosure, the stator core has a non-centrosymmetric structure, so that a cross-sectional area of a magnetic path in some region of the stator core is increased, which is beneficial to an improvement of an output force of the magnetic levitation bearing.

A motor including a rotor, a first arm, a mount, a stator, a first bearing, and a second bearing. The motor is configured to rotate the rotor. The mount connected to the first arm. The stator coupled to the mount. The first bearing located between and connecting the rotor to the stator. The second bearing located between and connecting the rotor to the mount. The first arm prevents movement of the stator and the mount.

An electrostatic oil ring (130, 150) has an annular ring body (142, 152) with a surface (132, 134, 136, 138, 154), wherein a portion of the surface (132, 134, 136, 138, 154) carries an electrostatic coating (140, 156) which electrostatically attracts lubricant (35a) in a lubricant reservoir (35) when the electrostatic oil ring (130, 150) passes through the lubricant reservoir (35). Further, an electrostatic oil ring assembly with a plurality of electrostatic oil rings (130, 150), and a dynamoelectric machine with an electrostatic oil ring assembly are provided.

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 wind turbine component includes an inner member and an outer member disposed relative to the inner member, wherein the inner and outer members move relative to each other. A plain bearing is coupled to one of the inner or outer member and configured to provide a fluid film for maintaining separation of and facilitating relative movement between the inner and outer members. A position adjustment mechanism is coupled to the one of the inner or outer member for selectively moving the plain bearing. A position controller may be operatively coupled to the position adjustment mechanism for controlling the position of the plain bearing. The wind turbine component may be a wind turbine generator with the inner member and outer member corresponding to one of the stator and rotor assemblies. Methods for controlling the generator are also disclosed.

A molded motor 100 includes a molded stator formed by providing a molding resin to a stator, a rotor inside the molded stator, a pair of bearings supporting a rotor shaft of the rotor, and an insulating bracket fitted in an inner circumferential part of an opening formed at an axial end of the molded stator to surround and support an outer ring of the bearing with a concave part formed at a center, and formed of an insulating resin.

Positioning apparatus for an electric motor and bearing block, wherein the electric motor includes a rotor, a rotor shaft and a stator. The positioning apparatus is configured at least partially from an elastic material and in a substantially pot-like manner with an interior and can be positioned in a central recess of the bearing block for at least partially receiving a first end of the rotor shaft.

An insulated bearing includes an outer ring, an inner ring, and a plurality of rolling elements. At least one of the outer ring and an inner ring is made of metal, the plurality of rolling elements are provided between the outer ring and the inner ring, so as to be freely rolled, and at least one of the outer ring and an inner ring is coated with an insulating layer. The insulating layer is formed of a mixture in which silicon carbide and/or aluminum nitride as an additive are/is dispersed in aluminum oxide as a base matrix. The content of the additive is 1 to 40 mass % with respect to the total amount of the mixture.