Mitsuba Corporation

Osamu Nakamura

Yukiyoshi Iso

Hirokazu Shoda

Atsushi Kawasaki

Hiroyuki Yoshida

Motor device includes: motor part including armature shaft; speed reduction mechanism which includes worm and worm wheel and outputs the rotation of the armature shaft at reduced speed; gear case which is provided with bottom part and opening part and accommodates the worm and worm wheel in rotatable manner; gear cover which covers the opening part of the gear case; circuit board which is arranged between the speed reduction mechanism and the gear cover; and board cover which is arranged between the circuit board and the speed reduction mechanism. The board cover is provided with positioning protrusion part protruding toward the gear case, the gear case is provided with positioning recess part into which the positioning protrusion part is press-fit, and the bottom surface of the positioning recess part and the tip surface of the positioning protrusion part press-fit into the positioning recess part face each other with gap therebetween.

Motor device

A replay plateis set to have a vertically and horizontally symmetrical shape when a worm wheelis viewed from its axial direction; the worm wheelis provided with an accommodating concave portionin which the relay plateis housed so as to be recessed in the axial direction; and a part of a non-slidably contacting surface in a slidably contacting surfaceof the relay plate, i.e., a non-slidably contacting surface S is covered with first and second fixing partsthat are provided around the accommodating concave portionand protrude in a direction intersecting with an axial direction of the worm wheel, the non-slidably contacting surface being a surface with which the contact plate is not slidably contacted.

Wiper motor and method of manufacturing the same

A gear side feeding terminal (U,V,W) connected to a motor side feeding terminal (U,V,W) provided to the end portion of a stator () in the axial direction of the stator () from the axial direction of a rotor () is provided on a control board () for controlling the rotor (), housed in a gear case () so as to be stacked on a speed reduction mechanism (SD) from the direction crossing the axial direction of the rotor (). In this manner, the wiper motor is composed of a brushless wiper motor (), and it is unnecessary to provide the gear side feeding terminal (U,V,W) so as to avoid the control board (). Accordingly, it is possible to prevent electric noises, and provide a wiper motor reduced in size and weight, and since it is unnecessary to form a clearance in the control board (), it is possible to provide a wiper motor further improved in degree of freedom for designing the control board ().

Brushless wiper motor and method for assembling the same

In a brushless wiper motor, a rotor () is rotatably provided inside a stator () provided with a coil (), one end side of a rotation shaft () in the axial direction is fixed to the axial center of the rotor (), a worm () is provided on the other end side of the rotation shaft () in the axial direction, the first and second bearings () are respectively provided on one end side of the rotation shaft () in the axial direction and the other end side of the rotation shaft () in the axial direction than the worm () of the rotation shaft (), the rotation shaft () is rotatably supported by only the first and second bearings (), and with the position of the first bearing () being defined as a reference position, a length thereof in the axial direction to the second bearing () is longer than a length thereof in the axial direction to the rotor (). Since a commutator and other parts are not provided on a free end side of the rotation shaft (), it is possible to provide a brushless wiper motor reduced in length of the rotation shaft (), and reduced in inertial mass of the free end side of the rotation shaft ().

Brushless wiper motor

A motor with speed reduction mechanism is provided with an anti-scattering coverfor grease, which holds grease applied to a mating part MT where a wormand a worm wheelare in engagement with each other, the anti-scattering coverfor grease is provided and closer to an openingthan the worm wheelalong an axial direction of the worm wheel. The anti-scattering coverfor grease has: a first wallextending from the openingtoward a bottomand formed between the wormand a side wallof a speed reduction mechanism housing unit; and a second wallextending in a direction intersecting with the first walland covering the mating part MT from the same side as the openingalong the axial direction of the worm wheel. The first walland the second wallof the anti-scattering coverfor grease hold grease attached to the worm, thereby preventing exhaustion of grease applied to the mating part MT where wormand the worm wheelare in engagement with each other.

Growing community of inventors

Gunma, Japan

Osamu Nakamura