A single phase permanent magnet motor includes a stator and a rotor. The stator includes a stator core with windings. The stator core includes a yoke and claw-poles. Each claw-pole forms an arc pole face which is an involute curved face. All arc pole faces cooperatively define a space for receiving the rotor. A gradually changing uneven air gap is defined between the arc pole faces and the rotor. When the motor powers off and stops, the pole axis of the rotor is offset from the central axis of the claw-poles by a certain angle to avoid the rotor to stop at a dead point position, thus facilitating next startup of the motor.

A four-pole stator assembly including a bobbin assembly; and two c-shaped stator cores, each c-shaped stator core comprising a back and first and second pole arms extending from the back. The bobbin assembly includes first and second bobbin portions, each bobbin portion comprising two hollow bobbin arms, each bobbin arm defining a slot for receiving a pole arm, and a winding wound around each bobbin arm. The c-shaped stator cores are arranged such that each c-shaped stator core bridges across both bobbin portions with one of the first and second pole arms extending through a slot in the first bobbin portion, and the other of the first and second pole arms extending through a slot in the second bobbin portion, the pole arms being fixed in the slots by adhesive.

An electric motor including: a frame; a rotor assembly including a magnet, a bearing assembly, an impeller, and a shaft; and a stator assembly including a stator core and a bobbin. The frame has an inner wall and an outer wall, the outer wall surrounds the inner wall and defines an annular channel between the inner wall and the outer wall, and diffuser vanes extend from the inner wall to the outer wall through the annular channel. The inner wall defines a bore for supporting the rotor assembly, and the outer wall defines a substantially cylindrical outer casing of the motor.

An electric motor comprising: a frame; and a stator assembly; the stator assembly including a bobbin assembly and at least one c-shaped stator core. The frame comprises at least one lug, the bobbin assembly includes at least one recess, and the stator assembly is fixed to the frame by fixing the lug inside the recess of the bobbin assembly.

Provided are multiple switched reluctance motors and excitation control methods for same. Motors with various structures are provided having the same structural characteristics, a stator formed of an even number of salient pole pairs and a rotor formed of an even number of salient pole pairs. The salient poles of the stator salient pole pairs are arranged opposite the salient poles of the rotor salient pole pairs, with minimal air gaps left between said salient pole pairs, thus leaving the shortest magnetic return paths between the stator salient pole pairs and the rotor salient pole pairs arranged opposite one another, thus satisfying the minimum reluctance principle of the switched reluctance motor. In addition, due to the magnetic isolation between each stator salient pole pair, the performance of the magnetic pole of each stator salient pole pair is controlled by an excitation control power source and changed independently.

A single phase permanent magnet motor includes a stator core, windings, and a permanent magnet rotor. The stator core includes an end portion and two spaced arm portions each including a connecting arm and a pole claw. Each pole claw has a long pole tip and a short pole tip, and forms a pole surface. The long pole tip of each pole claw corresponds to the short pole tip of the other pole claw with a slot opening formed there between. The slot opening causes the arc pole surface to be discontinued along a circumferential direction, and the arc pole surface is recessed inwardly to form a startup groove.

A single phase permanent magnet motor includes a stator core, windings wound around the stator core, and a permanent magnet rotor rotatable relative to the stator core. The stator core includes an end portion and a pole arm extending from the end portion. The pole arm includes two connecting arms spaced from each other and pole claws respectively formed at distal ends of the connecting arms. The two pole claws define a space for receiving a rotor therein. The pole claws surround the space and form an arc pole surface. The arc pole surface has a first axial portion continuous along a circumference of the arc pole surface and a second axial portion being discontinuous along a circumferential direction of the arc pole surface.

A motor (10) and a pump having the motor are provided. The motor (10) includes a stator (14) and a rotor (16) rotatable relative to the stator (14). At least one of the stator (14) and the rotor (16) has a magnetic core (20) and a winding (22) wound around the magnetic core (20). The magnetic core is mounted to a base body (18). The base body (18) has at least one recess (54) for receiving debris produced by mutual friction between the magnetic core (20) and the base body (18).

The present invention provides a stator core comprising an end portion and a pole arm extending from the end portion. The pole arm includes two spaced connecting arms and two pole claws respectively formed at distal ends of the connecting arms. The two pole claws define a space for receiving a rotor therein. The pole claws surround the space and form an arc pole surface. The arc pole surface forms a discontinuity opening along a circumferential direction. The discontinuity opening faces a spacing between the connecting arms and has a width changed along an axial direction.

A stator core includes an end portion, a first pole arm, and a second pole arm. The first pole arm includes two first connecting arms extending from the end portion and spaced from each other, and two first pole claws respectively formed at ends of the first connecting arms. The first pole claws are spaced from each other with an opening formed there between. The second pole arm includes two second connecting arms axially stacked to the two first connecting arms respectively and two second pole claws respectively formed at distal ends of the two second connecting arms. The two second connecting arms are connected with each other.