Abstract: A heating device for induction-heating a rotor core of an electric motor includes an induction heating coil disposed in a central hole of the rotor core, an alternating current power supply for supplying an alternating current to the induction heating coil, and a first magnetic flux shielding plate disposed on a first end face of the rotor core and having a first opposing surface opposed to the first end face of the rotor core. The first opposing surface of the first magnetic flux shielding plate has a first inner region and a first outer region located radially outward of the first inner region. The first inner region protrudes more toward the first end face than the first outer region. Clearance is formed between the first outer region and the first end face of the rotor core when the first inner region abuts the first end face of the rotor core.

Abstract: A rotor for an electric motor may include a shaft extending along a rotation axis of the electric motor and a rotor core comprising a plurality of core blocks fixed to the shaft and arranged along the rotation axis. The plurality of core blocks may include a first core block and a second core block that are oriented differently from each other in a circumferential direction about the rotation axis. Each of the plurality of core blocks may include an outer surface extending along the circumferential direction, a center hole through which the shaft passes, and an outer groove defined in the outer surface. An inner surface of the center hole may be in continuous contact in the circumferential direction with an outer surface of the shaft over an entire circumference thereof.

Abstract: A manufacturing method for manufacturing a rotor such that a permanent magnet is inserted into a slot hole of a rotor core with a spacer includes: a step of placing, on the rotor core, a guide whose upper end has a curved guide surface such that the guide space continues with the slot hole in the up-down direction; a step of placing the spacer on the guide so that the spacer lies across the guide space; a step of inserting the permanent magnet into the guide space with the spacer being wound around the permanent magnet; and a step of inserting, into the slot hole, the permanent magnet around which the spacer is wound.

Abstract: A manufacturing method for manufacturing a rotor such that a permanent magnet is inserted into a slot hole of a rotor core with a spacer includes: a step of placing, on the rotor core, a guide whose upper end has a curved guide surface such that the guide space continues with the slot hole in the up-down direction; a step of placing the spacer on the guide so that the spacer lies across the guide space; a step of inserting the permanent magnet into the guide space with the spacer being wound around the permanent magnet; and a step of inserting, into the slot hole, the permanent magnet around which the spacer is wound.