Rotor manufacturing method
A rotor manufacturing method for manufacturing a rotor of a rotary electric machine by disposing magnets in hole portions of a rotor core formed of stacked steel sheets, and injecting and curing a thermosetting resin to fix the magnets to the rotor core includes a temperature increasing step for increasing a temperature of the rotor core to a curing start temperature or higher, a resin injection step for causing a resin injection apparatus to inject the liquid resin at a melting start temperature or higher into the hole portions of the rotor core at the curing start temperature or higher, and a magnet fixing step for curing the resin by keeping the rotor core at the curing start temperature or higher.
1 . A rotor manufacturing method for manufacturing a rotor of a rotary electric machine by using a thermosetting resin having a characteristic that the thermosetting resin is solid at room temperature, liquefied by being heated to a melting start temperature or higher, and cured by being heated to a curing start temperature or higher, disposing magnet members in hole portions of a rotor core formed of stacked steel sheets, and injecting and curing the thermosetting resin to fix the magnet members to the rotor core, the rotor manufacturing method comprising:
a temperature increasing step for increasing a temperature of the rotor core to the curing start temperature or higher;
a resin injection step for causing a resin injection apparatus to inject the thermosetting resin in liquid state at the melting start temperature or higher and lower than the curing start temperature into the hole portions of the rotor core at the curing start temperature or higher after the temperature in creasing step; and
a magnet fixing step for curing the thermosetting resin by keeping the rotor core at the curing start temperature or higher, wherein:
in the temperature increasing step, the temperature of the rotor core is increased to a heating temperature equal to or higher than the curing start temperature,
in the magnet fixing step, the temperature of the rotor core is increased to a fixing temperature that is higher than the heating temperature and is a temperature at which curing of the thermosetting resin is finishable within a predetermined period after injection of the thermosetting resin in liquid state is finished in the resin injection step,
heat application units configured to heat the rotor core in the temperature increasing step and the magnet fixing step are provided outside the resin injection apparatus, the heat application units being configured to heat the rotor core in the temperature increasing step and the magnet fixing step are a same heat application unit, and
a heat application unit configured to heat the thermosetting resin to the melting start temperature or higher in the resin injection step is provided inside the resin injection apparatus.
2 . The rotor manufacturing method according to claim 1 , wherein in the resin injection step, the thermosetting resin in liquid state is injected in a state in which the rotor core is pressed in a stacking direction of the stacked steel sheets.
3 . The rotor manufacturing method according to claim 2 , further comprising a jig attaching step for disposing the stacked steel sheets in a holding jig and disposing the magnet members in the hole portions of the rotor core before the temperature increasing step.
4 . The rotor manufacturing method according to claim 3 , wherein the holding jig includes a first plate, a second plate having resin injection holes, and the first plate and the second plate press the rotor core in surface contact with the stacked steel sheets at both ends in the stacking direction.