Electric motor

An electric motor comprising a stator assembly, a rotor assembly including a plurality of rotor magnets, a detecting winding assembly and motor housing means containing and relatively positioning said stator assembly, rotor assembly and detecting winding assembly;

• said stator assembly including stator windings, a control circuit substrate having circuitry thereon for controlling a driving current supplied to said stator windings, means mounted on said current circuit substrate for detecting the rotational position of said rotor magnets, a bearing housing, an annular recess in said bearing housing having a reference surface and having a hook-shaped cross section, a bobbin about which said stator windings are wound, an end portion on said bobbin having serrations, and a compression spring interposed between said bearing housing and said bobbin, said annular recess, serrations and spring being arranged so that said serrations on said bobbin are urged by said spring into engagement with said reference surface of the annular recess to position said bobbin with respect to said bearing housing and stator windings;
• said rotor assembly including a shaft rotatably journalled in said stator assembly, a magnet casing secured to said shaft and within which said rotor magnets are fixed, and a detector magnet secured to said shaft;
• and
• said detecting winding assembly being disposed within said motor housing means in face-to-face relationship with said detector magnet for producing detecting signals in response to the rotation of said detector magnet with said shaft.

An electric motor comprising a stator assembly, a rotor assembly including a plurality of rotor magnets, a detecting winding assembly and motor housing means containing and relatively positioning said stator assembly, rotor assembly and detecting winding assembly;

• said stator assembly including stator windings, a control circuit substrate fixed relative to said stator windings so as to be positioned within the field of said rotor magnets, circuitry on said control circuit substrate for controlling a driving current supplied to said stator windings, and means mounted on said control circuit substrate for detecting the rotational position of said rotor magnets;
• said rotor assembly further including a shaft rotatably journalled in said stator assembly, a magnet casing secured to said shaft, said plurality of rotor magnets being fixed within said magnet casing, a detector magnet secured to said shaft, an annular groove containing an adhesive which firmly secures said plurality of rotor magnets in said magnet casing, a ring having a pair of opposed flanges in the circumferential periphery of said magnet casing and balance weight means for controlling the balance of said rotor assembly mounted between said pair of opposed flanges;
• and
• said detecting winding assembly being disposed within said motor housing means in face-to-face relationship with said detector magnet for producing detecting signals in response to rotation of said detector magnet with said shaft.

An electric motor comprising a stator assembly, a rotor assembly including a plurality of rotor magnets fixed therein, a detecting winding assembly and motor housing means which contains and relatively positions said stator assembly, rotor assembly and detecting winding assembly;

• said stator assembly including stator windings, a control circuit substrate fixed relative to said stator windings so as to be positioned within the field of said rotor magnets, circuitry on said substrate for controlling a driving current supplied to said stator windings, and means mounted on said control circuit substrate for detecting the rotational position of said rotor magnets;
• said rotor assembly including a shaft rotatably journalled in said stator assembly, a magnet casing secured to said shaft and within which said rotor magnets are fixed, said magnet casing having a bottom adjacent an end wall of said motor housing means, and a detector magnet secured to said shaft;
• said detecting winding assembly being disposed concentric with said detector magnet and including a plurality of cores, a speed detecting winding on said plurality of cores, a holder supporting said speed detecting winding and having a plurality of flexible integral detent levers thereon, said plurality of flexible detent levers having an inner surface accommodating an outer periphery of said cores, and a positioning pawl on each of said detent levers extending inwardly toward said cores;
• and
• said detector magnet and detecting winding assembly being disposed between said bottom of said magnet casing and said adjacent end wall of said motor housing means.