Patent ID: 7415756

Claim:
A method of assembling a rotor, comprising: providing a magnetizing jig for use in magnetizing magnets for insertion into magnet slots of an iron core portion of a motor rotor having a rotary axis, said magnetizing jig comprising a magnetizing jig body having a center axis, wherein said magnetizing jig body has magnet-receiving slots arranged for slidably receiving pre-magnetization magnets, respectively, to be magnetized while in said magnet-receiving slots, wherein said magnet-receiving slots extend through said magnetizing jig body along an axial direction of said center axis, wherein said magnet-receiving slots are formed in said magnetizing jig body so as to be spaced circumferentially about said center axis, wherein said magnetizing jig body is configured to be fitted to an upper end-face of the rotor such that said center axis aligns with the rotary axis of the rotor and said magnet-receiving slots of said magnetizing jig body align respectively with the magnet slots of the iron core portion of the rotor, wherein said magnetizing jig body is formed of a non-magnetic material such that the magnets, after having been magnetized in said magnet-receiving slots, do not stick to said magnetizing jig body, and wherein said magnetizing jig body further has magnet push-out holes formed therein along said magnet-receiving slots for receipt of magnet push-out pins to push the magnets, after having been magnetized, out of said magnet-receiving slots into the magnet slots of the rotor; inserting the pre-magnetization magnets into said magnet-receiving slots of said magnetizing jig body of said magnetizing jig; providing a magnetizing coil wound about an outer circumference of said magnetizing jig body; magnetizing the pre-magnetization magnets by supplying electricity to the magnetizing coil wound about the outer circumference of the magnetizing jig body to cause the magnets in said magnet-receiving slots of said magnetizing jig body to become magnetized magnets; fitting said magnetizing jig body to the upper end-face of the rotor such that said center axis of the magnetizing jig body is aligned with the rotary axis of the rotor and said magnet-receiving slots of said magnetizing jig body align respectively with the magnet slots of the iron core portion of the rotor; and inserting magnet push-out pins into the magnet push-out holes and operating the magnet push-out pins to push the magnetized magnets out of said magnet-receiving slots into the magnet slots of the iron core portion of the rotor.