Abstract: An axial directional gap type eccentric rotor having a stop position maintaining unit includes a commutator in which at least one air-core armature coil is arranged, a arc-shaped protruding portion installed at the outer circumference of the commutator so that at least part thereof faces the outer circumference portion of a donut-shaped magnet at the side of a stator, and an arc-shaped weight having magnetism arranged at least at part of the arc-shaped protruding portion. Thus, cost is lowered by reducing the number of the air-core armature coils. The loss of the main magnetic flux is prevented, without sacrificing a gap, by installing a weight having magnetism at a leakage magnetic flux portion. Also, the eccentric rotor can be moved or stopped at a position where the maximum torque is generated.

Abstract: A brushless motor having a transfer device includes a rotor in which a resin transfer device is disposed at one side of a rotor case, and a magnet is disposed at the other side of the case, a support portion integral with the rotor case to prevent the resin transfer device from being separated in an axial direction and sliding in a rotational direction, a shaft supporting the rotor, a stator base where a shaft holder for supporting the shaft is disposed, and a stator having armature coils for driving the rotor. Thus, the transfer device is prevented from being separated and strength in a rotational direction can be secured by the support portion. Also, the cost and the number of installation steps is reduced.

Abstract: A compact motor capable of being reflow-soldered, which can solve a problem of thermal demagnetization of a magnet with a simple structure, has magnets in a housing. At least a part of a surface to which the magnet is attached is separated by an acrylic adhesive sheet and heat resistant resin from metal members, such as a bracket and shaft forming part of the housing. The shaft is stainless steel having a low heat conductivity or an additional cover is used for the shaft to withstand reflow-soldering.

Abstract: An eccentric rotor includes an eccentric printed wiring commutator device having first and second surfaces, an expanded fan when viewed in a plane, a central hole for shaft installation, a plurality of segment patterns exposed toward a periphery of the first surface, at least one printed circuit armature coil at least one of the first and second surfaces, and an eccentric wound armature coil installation guide, wherein an end connection of each coil is arranged at an outer circumference during rotation; a wound, non-molded air-core coil incorporated in an air-core position determination guide and having an end portion connected to the end connection; a resin bearing holder inserted in the shaft installation hole with a first part protruding toward the segment pattern and a second part extending toward the second surface of the printed wiring commutator device; and a resin eccentric weight having a density-exceeding 3 at a fan-like arc-shaped portion of the printed wiring commutator device.

Abstract: A brushless motor having a resin bearing including a rotor with an integral output device at one side of a rotor case and a magnet at the other side, a shaft supporting the rotor, a resin bearing supporting the shaft for rotating, a stator base incorporating the resin bearing, a stator for driving the rotor, and an oil containing portion in the resin bearing. The oil containing portion includes grooves, a concave portion, and an oil barrier device located at the resin bearing, so the number of parts as well as the cost is reduced and a simple structure prevents the oil from leaking.

Abstract: In a rotor having a printed wiring commutator member as a printed wiring board in which a shaft installation hole is installed at the center of a printed wiring board, at least six segment patterns separated by slits are formed around the shaft installation hole, and simultaneously, at least three conductive bodies connect every two other segment patterns, terminal connection patterns are arranged at the outer circumference of the printed wiring board, a printed wiring commutator member is formed, not by through hole plating, as a means for forming the at least three conductive bodies for connecting every two other segment patterns, a plurality of air-core armature coils are installed at the side opposite to the segment patterns, and terminals of the air-core armature coils are connected to the terminal connection patterns through notches arranged at the outer circumference.

Abstract: The present invention provides a disc type eccentric rotor having at least two air-core coils, the rotor comprising a flat type commutator member having a shaft insertion through hole in the center thereof, a plurality of commutator land segments formed around the shaft insertion through hole on a first side of the flat type commutator member, wound type air-core coil arrangement guides formed around the shaft insertion through hole on a second side of the flat type commutator member, air-core coil end portion connection lands formed circumferentially on the second side of the flat type commutator member, a shaft holder installed around the shaft insertion through hole on the second side of the flat type commutator member, and wound type air-core coils installed at the wound type air-core coil arrangement guides and having the end portions thereof connected to the air-core coil end portion connection lands.

Abstract: A brush assembly for a small motor has brushes that are not separated from a commutator when the brushes contact the commutator. The brushes are arranged so that the angles formed by the brushes where the brushes contact the commutator are maintained uniform during assembly of the motor. The pair of brushes include bases connected to each other through a lead frame. The pair of brushes are embedded in a support by molding the support with middle portions of the brushes sandwiched by part of the support so that the angles formed by the pair of brushes where the brushes slidably contact the commutator are uniform.

Abstract: The semiconductor memory device comprising a plurality of memory cells aligned in a matrix form, and a plurality of bit lines respectively extending along the memory cells aligned in the longitudinal direction, wherein each of the bit lines is provided with a line section of the upper layer and that of the lower layer, and the mutually adjacent portions of the respectively adjacent two bit lines are provided in the different layers from each other. Due to this construction, such a conventional problem that the specific gravity of the coupling capacitance occupied within the whole bit-line capacitance is made large and an erroneous operation is caused due to this narrowed coupling capacitance can be solved.

Abstract: A dc brushless vibrator motor has a base member, a shaft connected to the base member, a stator having magnetically conductive cores and respective armature coils angularly uniformly disposed about the shaft and having an eccentric mass distribution. The rotor has a magnet holder, an annular permanent magnet fixedly connected to the magnet holder and concentric with the shaft and radially outside the stator. The magnet has alternating north and south magnetic poles arranged at a uniform angular pitch. In order to rotationally imbalance the rotor, an arcuate weight is fixed to the magnet holder and/or a part of the magnet holder is cut out.

Abstract: A radial gap, rotary yoke type brushless vibration motor which is driven by a sensor-less method includes a support body having a flat installation portion, a cylindrical coreless stator coil, one end of which is supported at the support body and the other end of which is open, a plurality of terminal portions arranged at the support body for connecting to the end of the cylindrical coreless stator coil at the support body, a shaft supported at the center of the support body, a cylindrical rotary yoke, functioning as an eccentric rotor supported by the shaft, accommodated inside the cylindrical coreless stator coil and separated from the cylindrical coreless stator coil via a radial gap, a rotor case, one end of which is fixed at the cylindrical rotary yoke, the rotor case made with a cut-out portion so as to be eccentric, and a magnet arranged inside the rotor case so as to face the outer circumference of the cylindrical coreless stator coil, the magnet separated from the cylindrical coreless stator coil via

Abstract: An eccentric rotor including a printed wiring commutator device where a hole for shaft installation is formed at the center thereof and a plurality of segment patterns are formed at the periphery of one surface thereof, a winding type armature coil integrally formed in a non-mold manner so as to be eccentric toward the other surface of the printed wiring commutator device, an end connection portion installed at such a position at the outer circumferential portion of the printed wiring commutator device that latching an end portion of the winding type armature coil is possible within a range of not deviating from the turning circumference during rotation and simultaneously electrical connection with the segment patterns is possible, and also at the position of not overlapping the winding type armature coil viewed from a plane, a resin bearing holder inserted in the shaft installation hole so that part thereof protrudes toward the segment pattern and simultaneously the other part thereof is extended toward the

Abstract: A spindle motor includes a rotor case in which a shaft support portion is installed at the center of the rotor and a plurality of disc mounting guides are formed by being lifted from the upper surface around the shaft support portion at a predetermined interval, a shaft installed at the shaft support portion, a disc chuck spring having at least one disc inner hold chucking portion and arranged at the rotor case such that at least one disc inner hole chucking portion slightly protrudes between the disc mounting guides, a magnet arranged inside the rotor case, an armature stator facing the magnet via a gap, and a stator base where the armature stator is arranged, the stator base supporting the shaft inside the armature stator.

Abstract: An eccentric rotor including a printed wiring commutator device where a hole for shaft installation is formed at the center thereof and a plurality of segment patterns are formed at the periphery of one surface thereof, a winding type armature coil integrally formed in a non-mold manner so as to be eccentric toward the other surface of the printed wiring commutator device, an end connection portion installed at such a position at the outer circumferential portion of the printed wiring commutator device that latching an end portion of the winding type armature coil is possible within a range of not deviating from the turning circumference during rotation and simultaneously electrical connection with the segment patterns is possible, and also at the position of not overlapping the winding type armature coil viewed from a plane, a resin bearing holder inserted in the shaft installation hole so that part thereof protrudes toward the segment pattern and simultaneously the other part thereof is extended toward the

Abstract: An eccentric rotor including a printed wiring commutator device where a hole for shaft installation is formed at the center thereof and a plurality of segment patterns are formed at the periphery of one surface thereof, a winding type armature coil integrally formed in a non-mold manner so as to be eccentric toward the other surface of the printed wiring commutator device, an end connection portion installed at such a position at the outer circumferential portion of the printed wiring commutator device that latching an end portion of the winding type armature coil is possible within a range of not deviating from the turning circumference during rotation and simultaneously electrical connection with the segment patterns is possible, and also at the position of not overlapping the winding type armature coil viewed from a plane, a resin bearing holder inserted in the shaft installation hole so that part thereof protrudes toward the segment pattern and simultaneously the other part thereof is extended toward the

Abstract: A non-circular flat motor in which terminal portions are installed at dead space and a manufacturing method thereof are disclosed. Since a flexible sheet type feeder terminal is not adopted, the motor can be easily held by a transferring apparatus and automatically mounted. Also, the feeder terminal has solderability and is easy to be reflow-soldered. A rotor and a housing supporting the rotor are formed to be non-circular when viewed in a plane. Feeder terminals or installation terminals are arranged at corner portions at the side surfaces of the housing which are angled and using a circle as an inscribed circle. At least one feeder terminal of a high electric potential is insulated from the other portion. The corner portion is formed to be concave so that each of the terminals is prevented from protruding outward from the housing. Each of the terminals are bent to be easily reflow-soldered and exposed to the side of the housing.

Abstract: A flat coreless vibrator motor holds a rotor in a specific position by magnetic flux from a magnet, increasing vibration by increasing the eccentricity of the center of gravity of the rotor, easily moving since the adjacent segments of a commutator are not short-circuited, and having reduced manufacturing costs. In the flat coreless vibrator motor, a four-pole magnet which has alternate north and south poles for providing a magnetic field to an eccentric rotor faces the eccentric rotor, in one side of which at least one coreless coil is located and in which a commutator having four segments, each diametrically-opposite pair of which are short-circuited, is installed.

Abstract: One end of a shaft is fixed to a first portion of a housing. An eccentric rotor is located in the housing rotatably on the shaft. The other end of the shaft is fitted into a concave portion on a second portion of the housing, so the rotor may be assembled in the housing in a simple manner and radial movement of the shaft can be prevented without enlarging the fixing portion of the shaft. Even if the diameter of the shaft is small, the shaft can withstand an impact resulting from dropping of the motor.

Abstract: A vibrator motor has a generally sector-shaped eccentric armature rotor that has a nonmagnetic body including core parts, around which armature coils are individually wound. The core parts are disposed at an even pitch angle, but within a 180.degree. angular range, about the rotational axis of the rotor. A rotor body of one embodiment consists of a first part and a second part that includes the core parts and the first part is made of a synthetic resin and the second part is made of a synthetic resin or a nonmagnetic but electrically-conductive metal. A rotor of an additional embodiment has a single-piece body of a synthetic resin that integrally has the core parts.

Abstract: A flat coreless vibrator motor has a case and a flat generally sector-shaped armature rotor. The rotor has a body that comprises a first part made of a first synthetic resin having a density of less than 1.8 and a second part made of a second synthetic resin having a density of greater than 5.0. The first part is disposed generally radially inside of the second part. A plurality of flat armature coils are molded in the first part and arranged at a predetermined pitch angle within an angular range of 180.degree. about the rotating axis of the rotor in non-overlapping relationship with one another. Alternatively, at least a portion of the second part is interposed between a field magnet of the motor and a cylindrical side plate of the case.