Minebea Company, Limited

Kunitake Matsushita

Yuzuru Suzuki

Hiroshi Sano

Takayuki Yamawaki

Toshihiko Nagata

Sakae Fujitani

Kazuo Muramatsu

Naoyuki Harada

Taketoshi Ohyashiki

Seiichi Matsuura

Masato Hata

Hideki Sakiyama

Taichi Nishio

Masaki Kagawa

Yoshiyuki Aono

Hiroichi Shibata

Hirohito Nakamata

Sylvie Belavsky

Hideki Matsuura

Hiroaki Ezure

Hiroshi Sakuma

Takashi Yoshikura

Michihiro Torii

Tohru Ohnuki

A low-profile stepping motor is disclosed, which is preferably used in downsized and lower-profiled electronic devices, such as a printer, a facsimile, a floppy disk drive, and the like. The motor comprises a stator assembly composed of first and second stator units (A, B) , and a rotor assembly () rotatably disposes inside the stator assembly. The stator units (A, B) are shaped and structured identically with each other, and each structured such that upper and lower stator yokes () , which each have a plurality of pole teeth formed along one side, and which each have an exciting coil () disposed toward one side opposite to the one side having the pole teeth, are coupled to each other with their respective pole teeth intermeshing with each other with a shift of 180 degree electrical angle. The stator units (A, B) thus structured are joined to each other such that respective distal pole teeth adjacent to each other are shifted from each other by an electrical angle of either 90 or 270 degrees, and in this way the stator assembly is completed.

Low-profile stepping motor

An electromagnetic actuator with high performance such as high speed and high resolution is inexpensively provided with solutions to problems associated with power supply and leakage flux, which have been involved in the structure of a moving coil type and have been shortcomings of a VCM type actuator. A composite electromagnetic actuator apparatus employs the foregoing electromagnetic actuator. The electromagnetic actuator is equipped with a stationary assembly that includes two coils disposed coaxially with each other inside a hollow stator yoke composed of a soft magnetic material, and a movable assembly composed of a movable magnet unit and a movable yoke unit both disposed inside the coils with a very small clearance therefrom so as to be movable in the axial direction, wherein the movable assembly travels in the axial direction by the interaction between a magnetic field generated by the movable magnet unit and a current passing through the coils.

Electromagnetic actuator and composite electromagnetic actuator apparatus

A mechanism for deflecting a headlamp optical axis comprises a connecting lever, a bracket, a stepping motor, a front end plate, and a traveling block. The bracket is attached to an outside frame constituting an automotive vehicle body, and the stepping motor is attached to the bracket in a horizontally movable manner. The stepping motor has a rotary shaft which has a screw formed thereon and engaging threadedly with the traveling block. The connecting lever is attached to the outside frame in a horizontally movable manner. In the mechanism structured above, when the rotary shaft rotates, the traveling block is caused to travel along the rotary shaft thereby causing the both ends of the connecting lever to move in respective arc paths, whereby an optical axis of a headlamp attached to one of the both ends of the connecting lever is deflected.

Mechanism for deflecting headlamp optical axis without speed reduction gears

A lead screw for a linear actuator, which has a metal pipe having a helical projection resin-molded on its outer surface, and a ball for a pivot bearing welded to a distal end of the metal pipe, is disclosed together with a method of manufacturing the same. With the lead screw according to this invention, a slight positional deviation from the origin, which is caused at a high ambient temperature by thermal expansion of a resin material filled up in the metal pipe, can be prevented reliably. Linear movement upon rotation of a stepping motor can take place with high precision.

Lead screw for linear actuator, and method of manufacturing the same

A claw-pole type stepping motor comprises: a rotor assembly shaped substantially cylindrical, and having a center shaft; and a stator assembly composed of two cup-shaped stator units which are coupled to each other coaxially so as to axially sandwich the rotor assembly, and which each include a bobbin having a magnet wire wound therearound, and two pole tooth arrays magnetically connected to each other and shifted in phase from each other by an electrical angle of 180 degrees. In the motor, each stator unit further includes a cover ring which protects the magnet wire wound around the bobbin against resin injected when the stator unit is resin-molded for an integrated solid structure. The motor structured as described above can be successfully resin-molded so as to enable elimination of a motor case, thus achieving downsizing for the dimension of the eliminated motor case while maintaining a sufficient mechanical strength.

Claw-pole type stepping motor

A motor has a hollow-cylindrical shaped rotary shaft provided with a hollow therein and is mounted on a PCB having an LED as light source. Light emitted from the LED passes through the hollow from one end of the rotary shaft to the other end, and irradiates an indicating needle attached to the other end of the rotary shaft.

Motor and panel meter incorporating same

In a motor, a shaft passes through a magnet of a rotor and is fixed to the magnet by way of a rotor sleeve formed by resin-molding between the magnet and the shaft. A resin-molded boss is fixed to a front end of a stator, has a center hole, and defines an inner surface continuous from the center hole and beveled so as to obliquely face a front end of the rotor sleeve. A plurality of bearing balls are rotatably disposed between the front end of the rotor sleeve and the beveled inner surface of the boss, thereby constituting a ball bearing which rotatably supports the shaft. Thus, the shaft is prevented from bowing, whereby the motor achieves a high rotational accuracy of the shaft without an additional bearing attached separately.

Motor with built-in bearing

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 low-profile stepping motor has a stator assembly structured such that first and second coil units are disposed flush with each other horizontally and are sandwiched between upper and lower stator yoke pieces each comprising first and second stator yokes which are punched out integrally with each other, are shaped symmetrically, and which each have a plurality of pole teeth along its semi-circular inner circumference. The upper and lower stator yoke pieces are fixedly put together via the coils such that hollow-cylindrical protrusions formed in the upper and lower stator yoke pieces are inserted into through-holes of first and second coil bobbins from the upper and lower sides, respectively, and have their abutting end surfaces welded, bonded or otherwise fixed to each other, whereby the coil units are surely held between the upper and lower stator yoke pieces.

Low-profile stepping motor with two coils arranged flush with each other horizontally

In order to reduce cost through reduction in material cost and improvement of productivity, in a linear type actuator comprising: a stator unit having coils consisting of wound magnet wires and housed inside stator sub-assemblies and pole teeth arranged on the inner circumference thereof; a rotor unit having a field magnet arranged on the outer circumference thereof and rotatably disposed so as to oppose the pole teeth with a given gap; an output shaft attached to a center portion of the rotor unit and movable in the axial direction thereof; and converting means provided on the innermost diametral circumferential surface of the rotor unit and adapted to convert rotary motion of the rotor unit into linear motion of the output shaft, the converting means is made of a material different from that of the rotor unit.

Linear type actuator

A claw-pole type stepping motor comprises: a rotor which is shaped substantially cylindrical, and which has a rotary shaft at its radial center; and two stators which are shaped like a cup, each have at least one magnetic coil, are coupled to each other so as to rotatably house the rotor with their magnetic coils located respectively toward both axial end faces of the rotor, and which each have two pole tooth arrays magnetically connected to each other such that magnetic phase difference therebetween at tips of respective pole teeth is 180 degrees in terms of electrical angle, and in the motor thus structure, three pipes of aluminum go axially through the two stators so as to hold together the two stators.

Claw-pole type stepping motor having radial dimension reduced without detriment to performance characteristic

There is provided a stepping motor of low vibration realized by reducing cogging with a simple structure while maintaining the performances such as torque. A stepping motor of the invention is structured such that a stator unitis composed of a pair of stator sub-assembliesattached to each other in a back to back manner, each stator sub-assembly having a plurality of pole teethformed at its inner circumference and housing a coil inside thereof, a rotor unitis rotatably disposed with a small gap from the plurality of pole teethand having multiple magnetic poles formed on ah circumference thereof, the multiple magnetic poles of the rotor unitbeing formed by magnetizing the rotor unitalternately with an S pole and an N pole in a circumferential direction, and that while a magnetic pole width consisting of a width of the S pole and a width of the N pole in a pair is set to a predetermined constant value, the width of the S pole and the width of the N pole in each pair are set to be different from each other.

Growing community of inventors

Shizuoka-ken, Japan

Kunitake Matsushita