Sanyo Electric Co., Ltd.

Tokyo Sanyo Electric Co.

Hironobu Sato

Hisashi Tokizaki

A stator according to the present invention comprises a circular nonmagnetic material having a bore into which a rotor is rotatably inserted, a plurality of teeth radially fitted to the material at equal intervals, stator wires wound around the teeth, and a yoke fitted to the outer peripheries of these teeth in such a way as to link the adjoining teeth.

Electric motor and method of producing the same

An outer rotor type brushless DC motor has: a first housing member formed of a sheet metal by press-working and having a first central bearing receiver also formed by press-working in the form of generally hollow cylinder; a second housing member formed from a sheet metal by press-working and having a second central bearing receiver also pressed in the form of generally hollow cylinder; a hollow cylindrical stator support formed of a sheet metal by press-working and having one end mounted on the first bearing receiver of the first housing member and another end for receiving the stator on the outer surface of the stator support; a magnets support press-worked from a electrical steel sheet metal for supporting magnets around the stator and inside the second housing member; a first bearing mounted in the first bearing receiver; a second bearing mounted in the second bearing receiver coaxially with the first bearing; and a freely rotatable shaft mounted on the first and second bearings, for firmly supporting thereon the stator support. The motor may be assembled in simple steps without any molding to suppress vibrations and noises. The motor has a suitable design for mass production.

Outer rotor type brusless DC motor

A shaded pole motor includes a squirrel-cage rotor and a stator assembly. The stator assembly having a bore for rotatably receiving the rotor and pole separation parts on an inner circumference of the bore so that adjacent separated portions are excited alternately to an N-pole and an S-pole when a winding is energized. The inner circumference of the bore is divided into plural sections represented by 2(2n+1). The magnetically divided two pole portions have pole sections having an alternating N-pole and S-pole, and non-pole sections, when a winding of the stator is energized.

Shaded pole motor

A brushless DC motor includes a rotor having a rotor shaft, rotor core and two different magnetic poles disposed around the rotor core, a stator having a circular aperture for receiving the rotor therein and a plurality of magnetic pole teeth consisting of a first tooth, a second tooth and a third tooth disposed on a circumference of the aperture at almost regular intervals. The stator has a first yoke portion for connecting the first tooth and the second tooth, a second yoke portion for connecting the second tooth and the third tooth, a first winding wound on the first yoke portion, a second winding wound on the second yoke portion, and a control device for controlling electrical conduction states of the first winding and the second winding according to the rotational position of the rotor.

DC brushless motor with three teeth and two windings

An easily restarted brushless DC motor has a skeleton type stator core, a rotor core having permanent magnets arranged around it, and needs only one position sensor adapted to detect a rotational position of a rotor and only one stator coil. A controller is provided for switching over the polarity of the electrical power supplied to the stator coil in accordance with an output of the position sensor.

Easily restarted brushless DC motor

A control device for brushless motor comprises an inverter (3), a control circuit (8) and a rotor position detecting circuit (9). In the rotor position detecting circuit (9), voltage induced in stator coils (U, V and W) due to rotation of a rotor (7) and neutral voltage at a virtual neutral point (25) are compared by comparators (CU, CV and CW) so that polarity changing points can be detected. The control circuit (8) controls the inverter (3) based on the above stated polarity changing points so as to control changeover of the modes for conducting to the stator coils (U, V and W). As a result, rotation of a brushless motor can be controlled without using Hall elements.

Growing community of inventors

Ohta, Japan

Hironobu Sato