A stator core comprises a stack and a resin portion. The stack comprises an annular yoke portion, a plurality of tooth portions, and a plurality of slots. The resin portion covers an inner wall surface of a slot of the plurality of slots. The resin portion protrudes outward relative to an end surface of the stack in a height direction of the stack. The resin portion is formed on at least a part of an end surface of the tooth portion so as to extend from the inner wall surface of the slot around the end surface of the tooth portion. A resin end portion of the resin portion is disposed on the end surface of the stack and a corner of the resin end portion is formed as an inclined surface including a planar surface or curved surface.

A stator core comprises a stack and a resin portion. The stack comprises an annular yoke portion, a plurality of tooth portions, and a plurality of slots. The resin portion covers an inner wall surface of a slot of the plurality of slots. The resin portion protrudes outward relative to an end surface of the stack in a height direction of the stack. The resin portion is formed on at least a part of an end surface of the tooth portion so as to extend from the inner wall surface of the slot around the end surface of the tooth portion. A resin end portion of the resin portion is disposed on the end surface of the stack and a corner of the resin end portion is formed as an inclined surface including a planar surface or curved surface.

A step of inserting an insulating paper into a slot of a stator core (second step) is performed, a step of placing a jig at a position that is on a side opposite to a side from which a segment coil is inserted into the slot of the stator core and that overlaps with a protrusion when viewed in an inserting direction of the segment coil (third step) is performed, and then a step of inserting the segment coil into the slot (fourth step) is performed. Therefore, even when the insulating paper is dragged by the segment coil in the process of inserting the segment coil into the slot, the insulating paper abuts the jig and the movement of the insulating paper is restricted, thereby suppressing displacement of the insulating paper from the slot.

A method of preheating an unfinished stator as an intermediate product before a stator as a final product for a motor is provided in order to preheat a mold for molding together with the unfinished stator in short time by using preheating facilities with simplified structures. In the method, the mold has a hollow and longitudinal barrel portion and a flange portion extending outward from an end of the barrel portion. The flange portion is arranged at a horizontal position to turn the barrel portion upward and an end of a cylindrical and longitudinal frame is put on the flange portion in a state where a core of the unfinished stator is fitted in the frame. A heat-resistant box of which an underside is opened covers the frame and the mold to surrounded outsides of the frame and the mold.

An insulation system for an electric machine coil includes the following layers situated in sequence over an insulated conductor: a first corona shield tape, a stress grading tape, a second corona shield tape having a first overlap length with the stress grading tape and a second greater overlap length with the first corona shield tape, an insulation tape, and a sealing tape.

A stator of an electric machine includes a laminated core having slots for receiving windings of a multiphase winding system. The windings have winding ends, which are encased with an insulator across a partial length. In order to encase the winding ends with the insulator, a strand of a thermoplastic material is extruded onto the winding ends via a nozzle. During extrusion, the nozzle is moved relative to the winding end along the longitudinal extent thereof and an oscillating movement of the nozzle transversely to the longitudinal extent of the winding end overlays the movement along the longitudinal extent. As a result the thermoplastic material lies on the winding end and around the respective winding end in the form of loops.

A method for producing a stator includes: providing a main body, the main body having: a cavity for accommodating a rotor, and a plurality of slots, extending axially through the main body, the plurality of slots accommodating electrical conductors of a winding, providing slot insulation so as to ensure that a slot interior of each slot of the plurality of slots is electrically insulated from the main body and is fluidtight; and forming a respective end plate on each of two ends of the main body, the end plates being attached in a fluidtight manner to the main body so as to ensure that no fluid can get between the end plate and the main body and reach the cavity of the main body. Each end plate has a radial part and an axial part, and the axial part has an insert.

A method for producing a stator includes: providing a main body, the main body having: a cavity for accommodating a rotor, and a plurality of slots, extending axially through the main body, the plurality of slots accommodating electrical conductors of a winding, providing slot insulation so as to ensure that a slot interior of each slot of the plurality of slots is electrically insulated from the main body and is fluidtight; and forming a respective end plate on each of two ends of the main body, the end plates being attached in a fluidtight manner to the main body so as to ensure that no fluid can get between the end plate and the main body and reach the cavity of the main body. Each end plate has a radial part and an axial part, and the axial part has an insert.

This armature has a core leg portion fixing member that is provided in a slot so as to overlap with a part at a position different from a position in an axial direction corresponding to a joint portion, and that includes a first fixing layer for fixing an armature core and a leg portion.

In manufacturing a magnet embedded core, creation of flash, and problems associated with flash are prevented. A device for manufacturing the magnet embedded core comprises a base (32) comprising an upper surface at which a resin pot chamber (64) for storing molten resin opens, a separator plate (36) detachably placed on the upper surface of the base (32) to support a rotor core (2) thereon and having a gate (50) and a cull opening (52) communicating the magnet insertion hole (4) of the rotor core (2) with the resin pot chamber (64), and a plunger (62) movably provided in the resin pot chamber (64) to press the molten resin in the resin pot chamber (64) into the magnet insertion hole (4) via the gate (50) and the cull opening (52), wherein an annular recess (66) is formed on the upper surface of the base (32) so as to extend outward of the resin pot chamber (64) and communicate with the resin pot chamber (64).