Mabuchi Motor Co., Ltd.

Kazuyuki Yamamoto

Satoshi Kikuchi

Takeshi Okumura

Shinichi Taniguchi

Kiyoto Itou

Yasuhiro Yamagata

Eiji Uenishi

Takashi Tai

A sliding surface sealing structure is a structure that seals a sliding surface between a rotating member that rotates about an axis and a sealing member that makes sliding contact with a circumferential surface of the rotating member, and includes: a wall surface configured to hold the sealing member between the wall surface and the circumferential surface of the rotating member; an opposing surface facing the sealing member with a gap therebetween; and a protruding portion protruding from the opposing surface toward the sealing member.

Sliding surface sealing structure, gear box, and motor unit

A motor unit for transmitting a driving force of a motor driven by a battery to an opening and closing mechanism through a worm gear and a worm wheel includes lubricating grease. The grease includes a solid additive that increases a friction coefficient between the worm gear and the worm wheel as its addition amount increases. The addition amount is not less than a first threshold and is not more than a second threshold. The first threshold is an addition amount for realizing a friction coefficient at which transmission efficiency from the worm wheel to the worm gear becomes 0 [%]. The second threshold is an addition amount for realizing a friction coefficient at which a starting voltage of the motor to move the opening and closing mechanism in an opening direction becomes a minimum guaranteed voltage of the battery after the opening and closing mechanism is restrained fully closed.

Speed reducer-equipped motor unit

A bearing unit includes: a thrust damper extendable in an axial direction of a shaft placed in a gearbox, the movement of which toward one side in the axial direction is regulated; a shaft receiver component held by the thrust damper on the other side of the thrust damper in the axial direction; a metal holder that holds the shaft receiver component in such a manner as to be detachable in the axial direction; and an oilless metal held by the metal holder and placed on the other side of the shaft receiver component, in which the thrust damper, the shaft receiver component, the metal holder, and the oilless metal are integrated all together before being incorporated into the gearbox.

Bearing unit and speed reducer-equipped motor

An annular sensor magnet to be fixed to a motor shaft by a press-fit includes an annular portion having magnetic poles alternately formed in an outer peripheral portion. The annular sensor magnet also includes a fixing portion extending from an inner peripheral portion of the annular portion toward a center to support and fix the motor shaft having been press-fit, and a stress reducing portion for reducing stress caused in a contact portion of the fixing portion that contacts the motor shaft when the motor shaft is press-fit onto the fixing portion. The sensor magnet includes a bonded magnet in which a magnetic material is dispersed in a plastic material.

Sensor magnet of motor having a fixing portion to press-fit to a shaft without a sensor magnet holder

A sensor magnet holder is used to fix a sensor magnet to a motor shaft. The sensor magnet holder includes a press fitting part to which the motor shaft is press fitted; a holding part provided radially outside the press fitting part to hold the sensor magnet; and a joint part that joins the press fitting part and the holding part. The joint part is configured such that at least a part of the joint part is deflected by an external force.

Sensor magnet holder, magnet fixing structure, and motor

A motor apparatus includes a sensor magnet configured to rotate integrally with a drive shaft of a motor; a housing including a sensor housing section in which the sensor magnet is located; a pulse output board including a magnetically permeable base and a rotation detection element mounted on a mounting surface of the base and adapted to detect rotation of the sensor magnet and output a pulse; and a terminal electrically connected with the pulse output board, wherein the terminal includes an insertion slot into which the pulse output board is inserted, and the insertion slot opens to the sensor housing section, and when the pulse output board is inserted, the insertion slot supports the pulse output board in a neighborhood of the sensor magnet with a reverse surface on a side opposite the mounting surface of the base facing the sensor magnet and electrically connects the pulse output board.

Motor apparatus

A worm gear includes a worm formed with a through hole through which a shaft transmitting the rotation of a motor is inserted, and a worm wheel configured to mesh with the worm and transmit the rotation to an output shaft. Given that a normal pitch is denoted by E and a width of a recess in the direction of a worm axis by H, the worm is configured such that H/E&#x2267;0.6 (1) is met.

Worm gear

A worm wheel () is structured integrally with an output shaft (). The worm wheel () includes the output shaft (), a circular flange () with the output shaft () placed as the center, and teeth () formed on the periphery of the flange () and in mesh with a worm. The flange () is provided with a first recessed flange portion () opposite to the side of the output shaft (), and the bottom () of the first recessed flange portion () has a ring-shaped first planar portion ().

Worm wheel, reducer, and motor with the reducer

In the present invention, driving torque outputted from a motor portion is transmitted to a worm from a motor shaft, further to a helical gear from the worm, and is taken out to the outside from an output shaft which rotates together with the helical gear with a fixed shaft fixed to a gear box as a center. This fixed shaft is constructed in a hollow and cylindrical shape having an opening in which one end portion thereof has been opened, and a ceiling surface in which the other end portion thereof has been closed, and one end portion of this fixed shaft is subjected to dislocation preventive work, and is fixed to a gear box made of resin by pressing-in or insert molding. The other end portion of the fixed shaft is formed with the dislocation preventive structure of the output shaft and the helical gear installed to the fixed shaft.

Method of manufacturing a gear unit of a motor

Driving torque outputted from a motor portion is transmitted to a worm from a motor shaft, further to a helical gear from the worm, and is taken out to the outside from an output shaft which rotates together with the helical gear with a fixed shaft fixed to a gear box as a center. This fixed shaft is constructed in a hollow and cylindrical shape having an opening in which one end portion thereof has been opened, and a ceiling surface in which the other end portion thereof has been closed, and one end portion of this fixed shaft is subjected to dislocation preventive work, and is fixed to a gear box made of resin by pressing-in or insert molding. The other end portion of the fixed shaft is formed with the dislocation preventive structure of the output shaft and the helical gear installed to the fixed shaft.

Gear unit of small motor

A small-sized motor equipped with a worm reducer according to the present invention includes a cavity portion,formed in a gear case,which accommodates a worm,mounted on a motor shaft,and a worm wheel,The cavity portion,receives a front end of the motor shaft,and does not communicate with the exterior thereof. A bearing holder,holding a bearing device is disposed in the cavity portion,such that a metallic-fiber-containing resin spacer or metallic spacer,is disposed between the bearing holder,and the gear case,Thrust adjustment for the motor shaft,is performed through application of thrust to the motor shaft,after the resin spacer is softened through induction heating effected electromagnetically from outside the gear case, or after a gear case protrusion, which is in contact with the metallic spacer, is softened through application of heat transmitted from the metallic spacer heated through induction heating effected electromagnetically from outside the gear case. Thus, the motor shaft can be fixedly positioned accurately with respect to the thrust direction.

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Matsudo, Japan

Kazuyuki Yamamoto