Abstract: A resonance drive actuator includes a casing; an electromagnetic drive section supported in the interior of the casing; a plunger to be reciprocatively driven at least in a rotational direction or in an axial direction by the electromagnetic drive section; an output shaft on which the plunger is fixed; and a spring which acts between the output shaft and the casing. The actuator resonantly drives a load connected to an end of the output shaft. The spring is a plate spring which integrally includes a casing inner-surface abutment portion fixedly abutting the inner surface of the casing, an output-shaft abutment portion fixedly abutting an outer surface of the output shaft, and a connection portion having the form of a strip and connecting the output-shaft abutment portion and the casing inner-surface abutment portion. The plate spring is fixed to both of the inner surface of the casing, and the output shaft.

Abstract: A small-sized motor having a polygonal outer shape includes four or more field magnets attached to the inner surface of a motor casing made of metal. A tubular portion of the motor casing is formed into a polygonal tubular shape such that flat side portions equal in number to field poles, and flat or curved corner portions equal in number to the field poles and each being located between the adjacent side portions are sequentially joined together. The field magnets have a smaller thickness at portions corresponding to the side portions of the motor casing and a larger thickness at portions corresponding to the corner portions of the motor casing. The field magnets are fixed while coinciding in center position with the corresponding corner portions of the motor casing and while being pressed against the corresponding corner portions of the motor casing from inside.

Abstract: An optical encoder device for a small-sized motor has a code wheel attached to a motor shaft which extends to the exterior of the motor through a bearing accommodated in a bearing-retaining section provided on an end bell of the motor, and a board on which a photosensor module is mounted such that an optical modulation track portion of the code wheel is positioned and disposed in a gap of the photosensor module. While a spacer is sandwiched between the end bell and the board, the motor, the spacer, and the board are fixed together by soldering a pair of motor terminals to a printed wiring portion of the board. The spacer has a generally U-shaped structure so as to allow fitting in position thereof from a direction orthogonal to the motor shaft.

Abstract: A photosensor module is composed of a light-receiving element module accommodating a light-receiving element, and a light-emitting element module accommodating a light-emitting element, which modules are separate, paired components. One of the paired light-receiving element module and light-emitting element module is mounted on a printed circuit board of a board unit, which is fixed to an end surface of a motor. After a code wheel is attached and fixed to the motor shaft along the axial direction of the motor shaft, a generally L-shaped module holder, which accommodates the other of the paired light-receiving element module and light-emitting element module, is mounted to the board unit. Thus, the light-emitting element and the light-receiving element are positioned such that these elements face each other via the optical modulation track portion of the code wheel.

Abstract: The invention provides a material for sliding contacts that is suitable for a small-sized DC motor used in recent downsized CD players and is excellent in durability. A material for sliding contacts used in a commutator of a small-sized DC motor that consists essentially of 0.01 to 3.0% Ni by weight, 0.01 to 6.0% ZnO by weight and/or 0.01 to 3.0% MgO by weight, furthermore, in some cases, 0.01 to 5.0% Cu by weight, and the balance Ag, in which Ni metal particles, ZnO particles or MgO particles are dispersed in the matrix of Ag.

Abstract: Each of the rotor magnetic poles is composed of a winding around a laminated core and each of both ends of each wound wire is connected to a commutator leg part coupled with a tip of a corresponding commutator segment of the commutator unit. Each of the commutator leg parts comprises a base portion extending outward in a direction substantially normal to the radial direction from the tip of the corresponding commutator segment tip and coupled to the commutator segment tip and a tip portion narrowed stepwise to let the ends of a wound wire be connected. A disk-shaped varistor having a hole at the center is mounted over the base portion of the commutator leg part, and each electrode of the varistor is soldered onto the corresponding base portion. Further, the commutator leg parts are punched and cut out of a reel-wound flat parent metal sheet and fixed to the commutator segment tips.

Abstract: In the present invention, by selecting an optimum combination of plating layer materials or materials, not only the manufacturing cost of motor brush is reduced but also a plating layer having excellent characteristics is formed in a narrow width on the surface of brush base material so as to have a predetermined thickness. The present invention is formed by a brush sliding portion that slides on a motor commutator and a plate-shaped brush base material that is slender as a whole and supports the brush sliding portion. This brush sliding portion is formed by Pd plating portion formed over a predetermined length on a part in the lengthwise direction of the brush base material that supports the brush sliding portion. This Pd plating is applied on the brush base material via backing Ni plating.

Abstract: The invention provides a material for sliding contacts that is suitable for a small-sized DC motor used in recent downsized CD players and is excellent in durability. A material for sliding contacts used in a commutator of a small-sized DC motor that consists essentially of 0.01 to 3.0% Ni by weight, 0.01 to 6.0% ZnO by weight and/or 0.01 to 3.0% MgO by weight, furthermore, in some cases, 0.01 to 5.0% Cu by weight, and the balance Ag, in which Ni metal particles, ZnO particles or MgO particles are dispersed in the matrix of Ag.

Abstract: A rotor for a small-sized motor has a plurality of rotor magnetic poles and a commutator on a rotor shaft, and both ends of a wire of each winding of the rotor magnetic poles are tied up with and connected by spot welding to a U-shaped hook-type commutator leg connected to the corresponding commutator piece end of the commutator, respectively. The commutator leg has a copper-based base material, and is composed by attaching a thin layer of a clad material with a melting point lower than that of the above described base material and a high electric resistance thereon at the surface part to be inside when bent to the U-shaped hook type. Thus, in the connection between the commutator leg and the copper wire material of the small-sized motor, the reduction of defectives of breaking of the wire because of heat shock at the time of welding is achieved, and in the meantime, the stabilization of welding is achieved, so that the reliability of the connection can be increased.

Abstract: A turntable-integrated spindle motor according to the present invention is constituted by a stator and a rotor. The rotor is constituted by a shaft 4 supported in a bearing in a cantilever support manner, a metallic rotor case 1 fixed to the shaft 4 by a boss 3, and a magnet 10 fixed to an inner circumferential surface of the rotor case 1. A plurality of projections 2 are formed integrally with the metallic rotor case so as to project from the side surface of the metallic rotor case, the projections being arranged along one circumferential line. The projections 2 perform a coming-off-prevention function by engaging with an engaging portion of a chassis 15. The rotor case 1 also functions as a turntable. In the present invention, the motor and the turntable are combined integrally with each other to obtain improved characteristics as well as to reduce the overall height. Also, projections for preventing coming off are formed integrally with the metallic rotor case to ensure high strength of the projections.

Abstract: A miniature motor includes a closed-bottomed cylindrical motor casing having a cylindrical bearing support portion projecting from a central portion of the bottom of the motor casing, a motor-casing-side bearing accommodated in the bearing support portion, a casing cover fitted to an open end portion of the motor casing, a casing-cover-side bearing accommodated in a central portion of the casing cover, and a rotor rotatably supported by means of the motor-casing-side bearing and the casing-cover-side bearing. The end face of the motor-casing-side bearing is concentrically polished at at least a portion which, when the rotor is urged toward the motor casing, abuts a washer provided on a shaft of the rotor. The above structure reduces sliding loss on the end face of an oil-impregnated bearing which receives a thrust load of the rotor generated due to rotation of the motor.

Abstract: A rotor for a small-sized motor has a plurality of rotor magnetic poles and a commutator on a rotor shaft, and both ends of a wire of each winding of the rotor magnetic poles are tied up with and connected by spot welding to a U-shaped hook-type commutator leg connected to the corresponding commutator piece end of the commutator, respectively. The commutator leg has a copper-based base material, and is composed by attaching a thin layer of a clad material with a melting point lower than that of the above described base material and a high electric resistance thereon at the surface part to be inside when bent to the U-shaped hook type. Thus, in the connection between the commutator leg and the copper wire material of the small-sized motor, the reduction of defectives of breaking of the wire because of heat shock at the time of welding is achieved, and in the meantime, the stabilization of welding is achieved, so that the reliability of the connection can be increased.

Abstract: The present invention provides a mechanical encoder device for use in a miniature motor, which encoder can provide, for each revolution of the motor, a plurality of pulses whose duty ratio does not change with time. A rotary contact portion 12 is provided on a rotor shaft 1, and a pair of rotation-detecting brushes 14 in sliding contact with the rotary contact portion 12 are provided on a brush holder 29 of an end cap 6. A plurality of rotary contact pieces 13 are arranged on the outer circumferential surface of the rotary contact portion 12 such that slits are formed therebetween. The paired rotation-detecting brushes 14 are each formed of a resilient metal and each assume the shape of a cantilever plate or wire spring whose side surface portion is subjected to sliding contact.

Abstract: A rotor for a small-sized motor has a plurality of rotor magnetic poles and a commutator on a rotor shaft, and both ends of a wire of each winding of the rotor magnetic poles are tied up with and connected by spot welding to a U-shaped hook-type commutator leg connected to the corresponding commutator piece end of the commutator, respectively. The commutator leg has a copper-based base material, and is composed by attaching a thin layer of a clad material with a melting point lower than that of the above described base material and a high electric resistance thereon at the surface part to be inside when bent to the U-shaped hook type. Thus, in the connection between the commutator leg and the copper wire material of the small-sized motor, the reduction of defectives of breaking of the wire because of heat shock at the time of welding is achieved, and in the meantime, the stabilization of welding is achieved, so that the reliability of the connection can be increased.

Abstract: A small-size motor has a case cover 11 formed with three voids, and electric elements such as chip capacitors are contained in the three voids. A first electric element is mechanically fixed between a pair of brush units in a first void and is electrically connected. The remaining two second and third electric elements are located on both sides of the first electric element and are pressed on a brush base in a motor shaft direction by a body earth terminal 14 in second and third voids, so that the body earth terminal 14 is fixed to the case cover 11 and the two electric elements are mechanically fixed and electrically connected. A sufficient space is secured in the motor case cover made of synthetic resin, so that three electric elements such as chip capacitors can be incorporated together with their wiring and support arrangement.

Abstract: Each of the rotor magnetic poles is composed of a winding around a laminated core and each of both ends of each wound wire is connected to a commutator leg part coupled with a tip of a corresponding commutator segment of the commutator unit. Each of the commutator leg parts includes a base portion extending outward in a direction substantially normal to the radial direction from the tip of the corresponding commutator segment tip and coupled to the commutator segment top and a tip portion narrowed stepwise to let the ends of a wound wire be connected. A disk-shaped varistor having a hole at the center is mounted over the base portion of the commutator leg part, and each electrode of the varistor is soldered onto the corresponding base portion. Further, the commutator leg parts are punched and cut out of a reel-wound flat parent metal sheet and fixed to the commutator segment tips.

Abstract: In the case of a small-sized motor of the present invention, a printed board to which an electric circuit including an electric element is attached is mounted on a case cover. The printed board has a soldering part to be connected to a member attached to an interior of the case cover for being connected to an electric power source supplied from an outside and a soldering part to be connected to a projection in a notch provided on an opening part side of the metal case to body-earth the electric circuit. In the soldering part for the body-earthing, at the time of assembling the motor, after fitting the case cover to the metal case opening part, a pair of electrodes are brought into contact from an outside of the metal case near the soldering part, to weld the soldering part by a principle of the electric resistance welding.

Abstract: The leading end of a wire to be wound fed from a coil winder is wound around one of commutator leg parts a prescribed number of turns and then wound around a corresponding salient pole. After that, it is similarly wound successively around other commutator leg parts and around other salient poles and, after it is wound around the same commutator leg part as the one around which the leading end of the wire was first wound, the wound wire is cut. Only the portions that will be wound around the commutator leg parts in synchronization with the feed of the wire to be wound from the coil winder are stripped of their insulating coat prior to being wound, and the wound portions of the commutator leg parts are welded.