Method of manufacturing a rotor
AssigneeMabuchi Motor Co., Ltd.
InventorHideki Itaya
Life of this patent
Estimating the term…
Abstract
A miniature electric motor has a stator mounted within a casing and a rotor provided so as to face the stator. The rotor includes a rotary shaft rotatably supported to the casing, a rotor body into which the rotary shaft is inserted, the rotor body being made of plastic, and a magnetic layer formed on an outer circumferential surface of the rotary body and made of rare earth plastic magnetic material. Accordingly, it is possible to obtain a high torque even with a small amount of rare earth plastic magnet and to avoid separation or cracks of the magnetic layer.
Claims4
A method for producing a rotor for a miniature electric motor in which a stator is provided within a casing and the rotor is provided so as to face the stator, comprising the following steps of:
- inserting a rotary shaft into a body of said rotor made of plastic;
- subsequently incorporating the rotor body into a molding die and at the same time positioning said rotary shaft relative to said molding die;
- and
- thereafter, injecting rare earth plastic magnet material, heated and molten at a temperature higher than a softening point t1 of said rotor body, into said molding die and forming a magnetic layer on an outer circumferential surface of said rotor body.
Dependencies are inferred from the claim text.