Abstract:
A rolling shutter driving device includes a motor, a locking assembly and a gearbox. The motor includes a stator and a rotor. The rotor includes a rotary shaft connected to the gearbox. The rotary shaft drives through the gearbox a rolling shutter to extend or retract. The locking assembly includes a brake pad slidingly fitted on the rotary shaft and a rotary member fixedly mounted to the rotary shaft. The brake pad is circumferentially fixed relative to the stator. The brake pad is slidable relative to the rotary shaft so as to be selectively engaged with the rotary member to lock the rotary shaft and hence hold the load in position, or disengaged from the rotary member to unlock the rotary shaft.
Abstract:
A single-phase motor, an airflow generating apparatus, and an electric apparatus are provided. The motor includes a stator and a rotor. The stator includes a stator core and stator windings. The stator core includes a ring-shaped yoke and multiple pole portions. A magnetic bridge or slot opening is formed between each two adjacent pole portions. An end surface of each pole portion includes an arc surface. A positioning groove is formed in each arc surface. The arc surfaces of the pole portions cooperatively form a receiving cavity. The rotor includes a rotary shaft and a permanent magnet fixed to the rotary shaft. The permanent magnet is received in the receiving cavity. The arc surfaces are located on a cylindrical surface centered around a rotation axis of the rotary shaft. The cogging torque of the motor can be reduced, thus reducing the startup current and hence the noise of the motor.
Abstract:
A single phase brushless motor includes a stator and a rotor. The stator includes a stator core and stator windings wound on the stator core. The stator core includes a yoke portion, and first and second pole portions extending inwardly from the yoke portion. An end surface of the first pole portion includes a first arc surface having a first groove. An end surface of the second pole portion includes a second arc surface having a second groove. The first and second arc surfaces are opposed to each other and define a receiving space therebetween. The rotor includes a rotary shaft and permanent magnetic poles fixed to the rotary shaft. The permanent magnetic poles are received in the receiving space. A substantially uniform gap is formed between the first arc surface and the second arc surface and the permanent magnetic poles.
Abstract:
A single-phase brushless motor includes a stator and a rotor rotatable with respect to the stator. The rotor includes a number of permanent magnetic poles. The stator includes a stator core and a winding wound on the stator core. The stator core includes an outer annular portion, an inner annular portion, and connecting portions connecting the inner and outer annular portions. The winding is wound around the connecting portions. The rotor is received in the inner annular portion. The inner annular portion and the rotor form a substantially uniform air gap. A recess is formed in an inner surface of a part of the inner annular portion between each pair of adjacent connecting portions. A center of each recess deviates from a center line of symmetry of the corresponding pair of connecting portions.
Abstract:
A single phase brushless motor and a power tool and a car window lifer employing the motor are provided. The motor includes a stator and a rotor. The stator includes a stator core and windings. The stator core includes a yoke and teeth extending inward from the yoke. The tooth includes a tooth tip. The tooth tip includes a first pole shoe and a second pole shoe. The tooth tip forms a positioning groove facing the rotor between the first and second pole shoes. The rotor is received in a space defined between the first and second pole shoes. The rotor comprises multiple permanent magnetic poles arranged in a circumferential direction of the rotor. The first and second pole shoes are symmetrical about a central line of the tooth body, such that the rotor startup capability in one direction is greater than the rotor startup capability in an opposite direction.
Abstract:
A single phase brushless motor and an electric apparatus are provided. The motor includes a stator and a rotor. The stator includes a stator core and windings. 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 rotor is received in a space defined between the first pole shoes and the second pole shoes. Each tooth forms a positioning groove facing the rotor between the first pole shoe and the second pole shoe. The first and second pole shoes are symmetrical about a central line of the tooth body and the positioning groove deviates toward the first pole shoe, such that the rotor startup capability in one direction is greater than the rotor startup capability in an opposite direction. The single phase motor has a larger startup torque with enhanced startup capability.