A step actuator includes a housing, a stator in the housing, a rotor including a magnet provided radially inward of the stator and a nut member inserted into the magnet and protruding through one side of the housing, a bearing rotatably supporting the nut member, a screw member coupled with the nut member to linearly move as the rotor rotates, and a mounting member supported on one side of the housing to support the screw member in such a manner that the screw member is linearly movable. The nut member includes an end portion passing through the bearing and a coupling portion extending from the end portion to couple with the bearing.

A rotor of a motor capable of improving durability of the motor by increasing a bonding force between a ring magnet and a resin. The rotor includes a ring magnet having an insertion hole passing through the center thereof, a shaft inserted into the insertion hole, and a resin that is disposed between the insertion hole and the shaft and fixes the ring magnet and the shaft. The resin extends to upper and lower surfaces of the ring magnet so as to cover at least parts of the upper and lower surfaces of the ring magnet.

A single phase brushless motor and a power tool are provided. The single phase brushless motor includes a stator and a rotor. The stator includes a stator core and windings wound around the stator core. The stator core includes a yoke and at least two teeth. The tooth includes a tooth body and a tooth tip. The tooth tip includes first and second pole shoes. The two pole shoes of each tooth are symmetrical about a center line of the tooth body. Each tooth defines a positioning groove facing the rotor between the two pole shoes. Pole shoes of adjacent two of the at least two teeth are spaced apart by a slot opening. A width of the positioning groove is greater than a width of the slot opening. The peak value of the cogging torque of the motor is increased, and the motor has a large startup torque.

A motor, a compressor, and a refrigeration device are provided. The motor includes a stator assembly and a rotor assembly. The stator assembly includes a stator core provided with a stator slot. The rotor assembly includes a rotor core and a permanent magnet. The stator core is sleeved outside of the rotor core or vice versa. The permanent magnet is arranged on the rotor core. By limiting the relationship between the distance between the stator core and the rotor core, the length of the permanent magnet in its own magnetization direction, the number of the stator slots, and the intrinsic coercivity of the permanent magnet, it is possible to adjust the strength of the demagnetization reverse magnetic field generated by energizing the motor.

A motor, a compressor, and a refrigeration device are provided. The motor includes a stator assembly and a rotor assembly. The stator assembly includes a stator core provided with a stator slot. The rotor assembly includes a rotor core and a permanent magnet. The stator core is sleeved outside of the rotor core or vice versa. The permanent magnet is arranged on the rotor core. By limiting the relationship between the distance between the stator core and the rotor core, the length of the permanent magnet in its own magnetization direction, the number of the stator slots, and the intrinsic coercivity of the permanent magnet, it is possible to adjust the strength of the demagnetization reverse magnetic field generated by energizing the motor.

An electric drive system includes a permanent magnet motor, rotor magnets connected to a rotor thereof, a heating source such as a resistive heating element connected to the rotor magnets, and an electronic controller. The controller selectively heats the rotor magnets via the heating source during a predetermined low-load/high-speed operating mode of the electric drive system. The controller may preemptively cool the rotor magnets, e.g., via pre-chilled electrical coolant, in response to a predicted or impending high-load/low-speed operating mode. The heating element may include a positive temperature coefficient heating element disposed between a rotor yoke and the rotor magnets. A method includes detecting the low-load/high-speed operating mode, and selectively heating the rotor magnets via a heating source during such a mode. A motor vehicle includes road wheels and the electric drive system, the motor of which powers one or more of the road wheels.

An electric drive system includes a permanent magnet motor, rotor magnets connected to a rotor thereof, a heating source such as a resistive heating element connected to the rotor magnets, and an electronic controller. The controller selectively heats the rotor magnets via the heating source during a predetermined low-load/high-speed operating mode of the electric drive system. The controller may preemptively cool the rotor magnets, e.g., via pre-chilled electrical coolant, in response to a predicted or impending high-load/low-speed operating mode. The heating element may include a positive temperature coefficient heating element disposed between a rotor yoke and the rotor magnets. A method includes detecting the low-load/high-speed operating mode, and selectively heating the rotor magnets via a heating source during such a mode. A motor vehicle includes road wheels and the electric drive system, the motor of which powers one or more of the road wheels.

A motor includes a rotor including a shaft centered on a central axis extending vertically, a bearing that supports the shaft, an air-core coil that is radially outward of the rotor and extends in an axial direction, and a back yoke that includes an axially extending shape with a linear portion having a coil shape, and includes an inner peripheral surface to which the air-core coil is fixed.

The present application relates to a media gap motor (10) and also a fuel cell system (1) comprising a media gap motor (10). The application additionally relates to a use of the media gap motor (10) and of the fuel cell system (1). The proposed media gap motor (10), for example for a fuel cell system (1), has a shaft (15), in which there is accommodated a rotor magnet (22). The media gap motor (10) additionally has a stator with stator windings (23) for electrically driving a rotation of the shaft (15). The media gap motor (10) furthermore has a housing (26), which delimits a flow space (11) formed between the shaft (15) and the stator. The media gap motor (10) further has an impeller (13) disposed in the flow space (11) and on the shaft.