Abstract: A PMDC motor includes a housing, a stator magnet fixed to the inner circumferential surface of the housing, a rotor core received in the housing and facing the stator magnet, and rotor windings wound around the rotor core. The rotor core includes a plurality of rotor teeth, each of the rotor teeth including a tooth body and a tooth tip. A ratio of the outer diameter of the rotor core to an outer diameter of the housing is in the range of 0.6 to 0.67. Compared to the existing PMDC motor, the PMDC motor of the present invention can satisfy the same performance requirement, while reducing the size and weight of the rotor core and hence the weight of the rotor windings. In this way, the total weight and hence the moment of inertia of the rotor is reduced, thereby effectively reducing the noise generated during operation of the motor.

Abstract: A medical pump includes a single phase synchronous motor, a rod piston, a cylinder for receiving the rod piston for reciprocating motion therein. The single phase synchronous motor includes a stator and a rotor rotatable relative to the stator. The rotor includes a plurality of permanent magnets. The stator comprises a stator core and a winding wound around the stator core. The stator core comprises two opposed pole portions that define there between a rotor receiving space for receiving the permanent magnets. The medical pump has a compact structure. In addition, the motor of the medical pump has a constant rotation speed and has a smaller size and less weight under the same output power conditions as traditional motors used in medical pumps. The medical pump is particularly suitable for use in atomizers.

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 PMDC motor includes a housing, a stator magnet fixed to the inner circumferential surface of the housing, a rotor core received in the housing and facing the stator magnet, and rotor windings wound around the rotor core. The rotor core includes a plurality of rotor teeth, each of the rotor teeth including a tooth body and a tooth tip. A ratio of the outer diameter of the rotor core to an outer diameter of the housing is in the range of 0.6 to 0.67. Compared to the existing PMDC motor, the PMDC motor of the present invention can satisfy the same performance requirement, while reducing the size and weight of the rotor core and hence the weight of the rotor windings. In this way, the total weight and hence the moment of inertia of the rotor is reduced, thereby effectively reducing the noise generated during operation of the motor.

Abstract: A driving device and a vehicle window lifter are disclosed. The driving device includes a motor and a gearbox. The motor includes a stator and a rotor. The gearbox includes a housing and a gear. The motor is mounted in the housing and includes a rotary shaft driving the gear. The housing supports the motor through a soft support structure. Two bearings are mounted in the housing at the same side of the stator for supporting and determining an orientation of the rotary shaft. Over-constraint to the rotary shaft is eliminated by reducing the number of the rigid support points between the rotary shaft and housing. The soft connection between the motor and housing can avoid or reduce motor vibrations transferred to the gearbox.

Abstract: A cooling fan and an air-cooled refrigerator are provided. The cooling fan includes a synchronous motor and an impeller. The synchronous motor includes a stator and a permanent magnetic rotor. The permanent magnetic rotor includes a rotary shaft and a permanent magnetic rotor main body attached around the rotary shaft. The stator includes a stator core and a stator winding wound around the stator core and powered by an alternating-current power supply. The permanent magnetic rotor operates at a constant rotational speed of 60f/p during a steady state operation of the motor, where f is a frequency of the AC power source and p is the number of pole pairs of the permanent magnet poles. The impeller is connected to the rotary shaft for rotation under the driving of the rotary shaft.

Abstract: An electric motor includes a stator and a rotor rotatably mounted to the stator. The rotor includes a rotary shaft; a rotor main body attached around the rotary shaft, the rotor main body and the rotary shaft being loosely fit with each other thus allowing for a rotation speed difference therebetween; and a buffering device arranged between the rotor main body and the rotary shaft for synchronizing rotation speeds of the rotor main body and the rotary shaft in a time-delayed manner. The motor is preferably a single phase synchronous motor. An electrical apparatus using the motor is also provided.

Abstract: An electric motor includes a stator and a rotor rotatably mounted to the stator. The rotor includes a rotary shaft, a rotor main body attached around the rotary shaft, the rotor main body being rotatable under the interaction between the rotor main body and the stator when the winding is energized. The rotor main body and the rotary shaft are in a loose fitting with each other to allow a rotation speed difference being existed between the rotor main body and the rotary shaft during startup of the rotor. A time-delayed synchronization mechanism is connected between the rotary shaft and the rotor main body and configured to eliminate, with time delay, the rotation speed difference between the rotor main body and the rotary shaft.

Abstract: A medical pump includes a single phase synchronous motor, a rod piston, a cylinder for receiving the rod piston for reciprocating motion therein. The single phase synchronous motor includes a stator and a rotor rotatable relative to the stator. The rotor includes a plurality of permanent magnets. The stator comprises a stator core and a winding wound around the stator core. The stator core comprises two opposed pole portions that define there between a rotor receiving space for receiving the permanent magnets. The medical pump has a compact structure. In addition, the motor of the medical pump has a constant rotation speed and has a smaller size and less weight under the same output power conditions as traditional motors used in medical pumps. The medical pump is particularly suitable for use in atomizers.

Abstract: A permanent magnet motor and a power tool are provided. The permanent magnet motor includes an excition and an armature. One of the excition and armature comprises a first magnetic core with permanent magnet members embedded therein. The permanent magnet members are arranged along a circumferential direction of the first magnetic core, such that an inner circumferential surface of the first magnetic core forms a plurality of magnetic poles with alternative polarities. The other of the excition and armature comprises a second magnetic core and windings. The second magnetic core is received in the first magnetic core and comprises teeth with the windings wound therearound. The embedded construction prevents the permanent magnet members from becoming disengaged from the magnetic core. A stronger magnetic pole can be formed by mutual induction of the permanent magnet members and the magnetic core, which increases the power density of the motor.

Abstract: A single phase motor and an electrical device are provided. The single phase motor includes a stator and a rotor. The stator includes a stator core and a winding wound around the stator core. The stator core includes a yoke and two opposed pole portions. Each pole portion includes short and long pole shoes. The rotor is received in a space defined by the short and long pole shoes of the two pole portions. The short pole shoe of each pole portion and the long pole shoe of the opposite pole portion are located adjacent to each other and define a slot opening therebetween. Each pole portion includes the short pole shoe and long pole shoe, which provides the motor with different startup capabilities along the clockwise and counter-clockwise directions.

Abstract: A refrigeration apparatus includes a fan and a motor for driving the fan. The motor is a single phase synchronous alternating current motor. In comparison with the traditional motor, the single phase synchronous alternating current motor has a reduced size and reduced cost, while ensuring the stable performance.

Abstract: A permanent magnet rotor includes a shaft, a rotor core fixed to the shaft, and multiple magnet sets. The rotor core has multiple groove sets for receiving the magnet sets. Each groove set has two grooves spaced apart by a first section of the rotor core. The first section has a width gradually decreasing from a radially inner end to a radially outer end. Each groove has a width gradually increasing from a radially inner end to a radially outer end. Each magnet set includes two magnets respectively received in the grooves of a respective groove set. The magnets of a magnet set are magnetized in a same direction, and every two adjacent magnet sets are magnetized in contrary directions creating multiple magnetic poles. The number of magnetic poles is equal to the number of magnet sets.

Abstract: A stator core includes at least one bendable strip-shaped core. Each strip-shaped core is formed by stacking a plurality of laminations. Each lamination includes at least two yoke portions and at least two tooth portions. Every two adjacent yoke portions are connected to each other via a bendable portion and have two opposite end surfaces, one of the end surfaces having a groove and the other having a projecting rib. After the bendable portion is bent the projecting rib is engaged in the groove to form an interlock structure such that relative circumferential movement between the adjacent yoke portions is limited.

Abstract: An electric motor has a wound stator and a permanent magnet rotor. The rotor includes a shaft, a hub fixed on the shaft, a plurality of rotor core segments and magnets fixed around the hub, and a pair of covers fixed to axial ends of the rotor core segments. The hub and covers are formed on the rotor core segments by inserting molding and one of the covers has openings to allow the magnets to be inserted into spaces formed between adjacent rotor core segments such that the rotor core segments and magnets are alternately arranged in a circumferential direction of the rotor.

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 solenoid includes a stationary member, a movable member being movable relative to the stationary member and spring disposed between the stationary member and the movable member. The stationary member includes a housing with an end wall and a side wall, a first permanent magnet attached to the end wall, a second permanent magnet attached to the side wall and a magnetic flux concentrator configured to concentrate a magnetic field generated by the second permanent magnet with a magnetic field generated by the first permanent magnet. The movable member includes a head inserted into the housing. The head is made of magnetically conductive material. The stationary member further includes a coil surrounding the head of the movable member. When the coil receives a pulse current, the movable member is driven from an extended/retracted position to a retracted/extended position.

Abstract: A relay has a driving device that includes a magnet portion, two electromagnets, a yoke portion fixed to the above elements, and a rocking armature. The magnet portion includes a ferrite permanent magnet polarized in a direction perpendicular to the yoke portion and a bearing surface facing way from the yoke portion. Each electromagnet includes an iron core fixed to the yoke portion and a coil wound thereon. The two iron cores are arranged at opposite sides of the magnet portion. The rocking armature includes two arms connected to each other with an included angle formed therebetween and a convex joint of the two arms. The convex joint abuts against the bearing surface and the rocking armature pivots about the convex joint between a first position and a second position in which the rocking armature contacts a respective one of the iron cores.

Abstract: A relay has a driving device that includes a magnet portion, two electromagnets, a yoke portion fixed to the above elements, and a rocking armature. The magnet portion includes a ferrite permanent magnet polarized in a direction perpendicular to the yoke portion and a bearing surface facing way from the yoke portion. Each electromagnet includes an iron core fixed to the yoke portion and a coil wound thereon. The two iron cores are arranged at opposite sides of the magnet portion. The rocking armature includes two arms connected to each other with an included angle formed therebetween and a convex joint of the two arms. The convex joint abuts against the bearing surface and the rocking armature pivots about the convex joint between a first position and a second position in which the rocking armature contacts a respective one of the iron cores.

Abstract: An electric motor has a wound stator and a permanent magnet rotor. The rotor includes a shaft, a hub fixed on the shaft, a plurality of rotor core segments and magnets fixed around the hub, and a pair of covers fixed to axial ends of the rotor core segments. The hub and covers are formed on the rotor core segments by inserting molding and one of the covers has openings to allow the magnets to be inserted into spaces formed between adjacent rotor core segments such that the rotor core segments and magnets are alternately arranged in a circumferential direction of the rotor.