Minebea Company, Limited

Hideki Sakiyama

Yuzuru Suzuki

Sakae Fujitani

Haruyoshi Hino

Hiroshi Sano

Kunitake Matsushita

Naomi Inoue

Taketoshi Ohyashiki

A support hole, screw holes, and eleven orientating holes are formed in a plate. The orientating holes are each positioned asymmetric to any other thereof about a center of the plate.

Plate and electric device

A bobbin comprises: a bobbin body consisting generally of a cylinder having a winding of a magnet wire therearound, and two flanges; and a bobbin cover formed generally into a cylindrical ring. The bobbin body includes a coil termination block protruding radially from an inner flange of the two and having terminal pins for external connection, and the bobbin cover includes a termination protector protruding radially from the bobbin cover and adapted to mate with the coil termination block when the bobbin cover is put over the bobbin body.

Bobbin provided with cover for protecting magnet wire

A motor structure including a rotor 1 having a permanent magnet 10 where north poles and south poles are alternately disposed in a moving direction of the rotor, a stator 5a including at least two stator yokes having stator pole teeth 3a, 4a respectively which face to the permanent magnet at a distance and are respectively positioned side by side in the moving direction to bear north poles or south poles respectively due to an electric current flowing through a coil 2a to thereby form at least one phase, wherein the stator pole teeth 3a, 4a are different from each other with respect to an effective area through which magnetic flux passes, whereby high harmonic wave phases generated from the pole teeth 3a, 4a are different from each other by 180 degrees in electric angle to thereby be canceled mutually, therefore an induced electromotive force wave containing hardly high harmonic wave is obtained to thereby reduce a motor vibration.

Motor structure

To reduce as much as possible the motor vibration due to the effect of harmonic components contained in the induced electromotive force waveform induced in the armature coil. In a motor structure, the pole tooth shapes of one pole tooth and the corresponding pole tooth thereto constituting one phase are made different from each other by changing their areas or amounts of skew, whereby the third harmonics caused by variations in the magnetic fluxes interlinking with these pole teeth are caused to cancel each other. Thus, the rotational vibration which has hitherto been a problem can be reduced and, further, the accuracy of the rotor movement can be improved without lowering the dynamic torque characteristic of the motor.

A claw pole type synchronous motor has input frequency increasing portions in a form of notches or holes formed in portions of claw poles which have the lowest magnetic flux densities so that the motor operates in a range from a low frequency to a high frequency without lowering torques too much.

Growing community of inventors

Shizuoka-ken, Japan

Hideki Sakiyama