A motor-driven compressor with a housing and an electric motor includes a stator that includes a stator core including a yoke and teeth, an insulator including an insulator base in contact with an end face of the yoke, and three-phase windings, each being wound around the corresponding teeth in a concentrated manner so as to form coils. The winding of each phase forms connection wires locked on an outer circumferential surface of the insulator base. Each connection wire connects adjacent coils of the corresponding phase. The outer circumferential surface includes a locking surface including accommodation grooves, each accommodating the corresponding connection wire, and a non-locking surface that does not lock the connection wires. The stator core includes an engagement recess that engages with part of a jig. The engagement recess is located radially outward from the insulator base on the end face and located radially outward from the non-locking surface.

An electric machine includes a plurality of magnetic stator laminations arranged in a first stacked configuration, a plurality of magnetic rotor laminations arranged in a second stacked configuration, and one or more virtual notches formed in each stator lamination and/or each rotor lamination. Each virtual notch is non-magnetic and configured to function as a physical notch, without removing material from the magnetic stator lamination, to increase mechanical strength in the first and/or second stacked configuration and reduce noise/vibration/harshness (NVH) in the electric machine.

In a rotating body and a rotating electric machine, a rotary shaft made of a magnetic body, a rotor fixed to the rotary shaft, and a pair of bearing sleeves for an air bearing that have a cylindrical shape, are mounted on one end portion and the other end portion of the rotor in an axial direction, and have wear-resistant coating layers on outer peripheral surfaces are provided, and the pair of bearing sleeves for an air bearing are provided with the wear-resistant coating layers before assembly to the rotary shaft.

In a rotating body and a rotating electric machine, a rotary shaft made of a magnetic body, a rotor fixed to the rotary shaft, and a pair of bearing sleeves for an air bearing that have a cylindrical shape, are mounted on one end portion and the other end portion of the rotor in an axial direction, and have wear-resistant coating layers on outer peripheral surfaces are provided, and the pair of bearing sleeves for an air bearing are provided with the wear-resistant coating layers before assembly to the rotary shaft.

A stator structure is provided and includes a plurality of first lamination layers, a plurality of second lamination layers, two third lamination layers and two oil spraying rings. The second lamination layers are sandwiched in between the first lamination layers. The second lamination layer located in the middle of the stator structure is sandwiched in between the two third lamination layers. The two oil spraying rings are connected to two first lamination layers located at outermost sides. Another stator structure is provided and includes a plurality of first lamination layers, a second lamination layer and two oil spraying rings. The second lamination layer is sandwiched in between two first lamination layers. The two oil spraying rings are connected to two first lamination layers located at outermost sides. By means of the arrangement of the aforesaid stator structure, the invention can effectively improve heat dissipating effect for oil cooling.

A stator structure is provided and includes a plurality of first lamination layers, a plurality of second lamination layers, two third lamination layers and two oil spraying rings. The second lamination layers are sandwiched in between the first lamination layers. The second lamination layer located in the middle of the stator structure is sandwiched in between the two third lamination layers. The two oil spraying rings are connected to two first lamination layers located at outermost sides. Another stator structure is provided and includes a plurality of first lamination layers, a second lamination layer and two oil spraying rings. The second lamination layer is sandwiched in between two first lamination layers. The two oil spraying rings are connected to two first lamination layers located at outermost sides. By means of the arrangement of the aforesaid stator structure, the invention can effectively improve heat dissipating effect for oil cooling.

A method for producing a stator for an electrical machine, the stator having a substantially hollow-cylindrical stator core, which has a plurality of grooves spaced apart in a circumferential direction, the method including: providing at least one strip-shaped winding unit having a first winding conductor with a plurality of groove portions running straight in a transverse direction that are mutually parallel; fastening a first end of the winding unit to a lateral surface of a mandrel; winding the winding unit onto the mandrel such that it is bent around the lateral surface of the mandrel spirally; inserting the mandrel, together with the winding unit, into a cavity in the stator core; and unwinding the winding unit from the mandrel with the groove portions of the winding unit being inserted into the grooves of the stator core.

A method for producing a stator for an electrical machine, the stator having a substantially hollow-cylindrical stator core, which has a plurality of grooves spaced apart in a circumferential direction, the method including: providing at least one strip-shaped winding unit having a first winding conductor with a plurality of groove portions running straight in a transverse direction that are mutually parallel; fastening a first end of the winding unit to a lateral surface of a mandrel; winding the winding unit onto the mandrel such that it is bent around the lateral surface of the mandrel spirally; inserting the mandrel, together with the winding unit, into a cavity in the stator core; and unwinding the winding unit from the mandrel with the groove portions of the winding unit being inserted into the grooves of the stator core.

A stator includes: a stator core having an annular shape, a coil, and a cover member having a cylindrical shape. The stator core includes a plurality of teeth portions that are aligned in a circumferential direction and a plurality of slots that are formed between the teeth portions which are adjacent to each other in the circumferential direction. In the coil, a plurality of conductor wire portions are wound around each of the teeth portions through the slots. The cover member is arranged to be inserted into an inner circumferential portion of the stator core such that an outer circumferential surface faces an opening on an inside in a radial direction of the plurality of slots. A foamable insulation member that covers an outer surface of the plurality of the conductor wire portions of the coil and is bonded to the outer circumferential surface of the cover member through the opening of the slots is loaded in each of the slots.

A method for manufacturing a rotor for a rotary electric machine, the method including supporting a workpiece including a rotor core and a rotor shaft that is hollow and disposing the rotor shaft on an inner diameter side of the rotor core. Using an actuation member that is positionable in a hollow interior of the rotor shaft, having a cavity on a radially inner side, and is radially displaceable or deformable, so the actuation member radially faces or contacts a molding pressurization region on an inner peripheral surface of the rotor shaft. Applying a force in a radial direction to the actuation member while bringing the drive member into contact with a contacted portion of the actuation member in the cavity by applying a force in an axial direction to the drive member.