Abstract: A stator includes a base board, a plurality of coil patterns patterned on one face of the base board, a stator core having a ring-like portion formed in a ring-like shape, a plurality of teeth base ends of which are fixed to the ring-like portion and front end portions formed respectively at front ends of the plurality of teeth in which the coil patterns and the teeth are laminated onto the base board to be respectively opposed to each other, and covers having base members bonded to the base board in a state of being respectively fitted to the plurality of teeth and covering surroundings of the respective teeth and conductive patterns patterned to inner faces of the base members and electrically connected to the coil patterns.

Abstract: A stator includes a base board, a plurality of coil patterns patterned on one face of the base board, a stator core having a ring-like portion formed in a ring-like shape, a plurality of teeth base ends of which are fixed to the ring-like portion and front end portions formed respectively at front ends of the plurality of teeth in which the coil patterns and the teeth are laminated onto the base board to be respectively opposed to each other, and covers having base members bonded to the base board in a state of being respectively fitted to the plurality of teeth and covering surroundings of the respective teeth and conductive patterns patterned to inner faces of the base members and electrically connected to the coil patterns.

Abstract: A motor has an armature disposed on one of a rotor and a stator and a permanent magnet disposed on the other of the rotor and the stator. The permanent magnet has skewed magnetic poles being magnetized so that a boundary between each pair of skewed magnetic poles is generally S-shaped and opposed areas of pole surfaces of the permanent magnet and the armature gradually increase when the pole surface of the permanent magnet enters a magnetic field region of the pole surface of the armature or gradually decrease when the pole surface of the permanent magnet leaves a magnetic field region of the pole surface of the armature.

Abstract: Variable optical attenuator and system are offered that permit fine adjustment of the amount of shielding, eliminate variations in the amount of shielding, and facilitate positioning. The variable optical attenuator is mounted in a region of a collimated beam formed between a pair of opposite optical systems. The attenuator continuously attenuates the collimated beam. The attenuator comprises a shielding plate and a pushing means for pushing against one face of the shielding plate, placing it in position, and producing flexural deformation. The shielding plate has a fixed base-end portion and a front-end portion that is so held as to be a free end. At least the base-end portion consists of a leaf spring. The amount by which the collimated beam is shielded by the front end is varied according to the amount of flexural deformation of the shielding plate.

Abstract: A double sleeve type dynamic bearing comprises a fixed shaft having at least one end fixedly mountable to an apparatus in which the bearing is utilized, a rotary sleeve arranged coaxially with the fixed shaft so that a first fine gap is formed therebetween, a fixed sleeve arranged coaxially with the rotary sleeve so that a second fine gap is formed therebetween, and a lubrication oil filled in the fine gaps. The first fine gap and the second fine gap each have an open end exposed to air outside the bearing and an opposite end that is not exposed to the air, the opposite ends being in communication with each other. A holding member holds the fixed shaft and the fixed sleeve and is disposed adjacent to a lower end surface of the rotary sleeve to form a third fine gap between the holding member and the lower end surface of the rotary sleeve. The third fine gap is formed with a thrust dynamic pressure producing groove, and opposite ends of the first and second fine gaps meet each other through the third fine gap.

Abstract: A method for lubricating a part without leaving air bubbles includes the steps of assembling components so that an open end is formed for application of lubricating fluid and a fluid path is provided through which the lubricating fluid is to be circulated, introducing the lubricating fluid into the open end and applying a centrifugal force to the component by moving the component about a circular path so that the centrifugal force causes the lubricating fluid to be urged throughout the fluid path. The method is used in an embodiment to lubricate a dynamic pressure bearing having a gap between relatively moving parts. The gap has an open end into which the lubrication fluid is dripped and a closed end. During movement of the bearing about a circular path, the fluid is urged from the open end to the closed end.

Abstract: In order to alleviate mutual interference between axial dynamic pressure portions and a radial dynamic pressure portion in a ring-like hydraulic dynamic pressure bearing, in the case of a ring-like hydraulic dynamic pressure bearing 1 constituted by supporting a shaft portion 4 constituted by fixing a ring 3 to an end portion 2A of a shaft main body 2 by a bearing portion 5, ring-like spaces 8 and 9 for storing lubricant for generating dynamic pressure are provided along contiguous portions of the radial dynamic pressure bearing portion and the axial dynamic pressure bearing portions formed between the ring 3 and the bearing portion 5, and the ring-like spaces 8 and 9 are maintained at atmospheric pressure via paths formed at the bearing portion 5 to thereby prevent negative pressure from generating at boundary regions of the two dynamic pressure bearing portions.

Abstract: The present invention is a double sleeve type fluid dynamic pressure bearing, comprising a fixed shaft having respective ends to be fixed to a utilized apparatus; a rotary sleeve arranged to provide a first fine gap between an inner peripheral surface thereof and an outer peripheral surface of the fixed shaft, a fixed sleeve arranged to provide a second fine gap between an inner peripheral surface thereof and an outer peripheral surface of the rotary sleeve, a holder member arranged to cooperate with a lower end surface of the rotary sleeve to provide a third gap, and wherein the first fine gap and the second fine gap are formed with radial dynamic pressure producing grooves while the third fine gap is formed with a thrust dynamic pressure producing groove, the first, second and third fine gaps being filled with lubrication oil, the first fine gap and the second fine gap having one ends made as opening ends contacting with the air and the other ends made as closed ends communicated with each other through the

Abstract: A spindle motor comprises a base, a stator coil connected to the base, and a sleeve-and-bearing unit connected to a central portion of the base. The sleeve-and-bearing unit has a sleeve and a bearing section mounted in the sleeve having a linear expansion coefficient greater than that of the sleeve. The sleeve has a groove disposed in an outer peripheral surface thereof for receiving an adhesive material for connecting the base to the outer peripheral surface of the sleeve. A rotor unit is connected to the sleeve-and-bearing unit for undergoing rotation relative to the sleeve-and-bearing unit. The rotor unit has a shaft section supported by the bearing section for undergoing rotation, a hub connected to the shaft section for rotation therewith, and a rotor magnet connected to the hub and disposed opposite to and spaced apart from the stator coil.

Abstract: A hydraulic dynamic bearing has a rotational assembly and a bearing member for rotationally supporting the rotational assembly. The bearing member has a main body having a recess portion and a cover for covering an open end of the recess portion. The rotational assembly has a shaft main body having an end portion extending into the recess of the bearing main body for undergoing rotation relative thereto and a ring member disposed in the recess of the bearing main body. The ring member is connected to the end portion of the shaft main body for rotation therewith. Axial dynamic pressure generating grooves are formed in upper and lower surface portions of the ring member for generating axial dynamic pressure during rotation of the rotational assembly. Radial dynamic pressure generating grooves are formed in an outer peripheral surface portion of the ring member for generating radial dynamic pressure during rotation of the rotational assembly.

Abstract: In a method for assembling a spindle motor having a liquid dynamic pressure bearing having a flanged shaft member formed by press-fitting a dynamic pressure ring member on a cylindrical member, a hub is press-fit on the flanged shaft member without causing deviation in the press-fit position of the dynamic pressure ring member. A hub press-fitting apparatus press fits a mount hole of the hub on a cylindrical end portion of the cylindrical member. The hub press-fitting apparatus comprises a hub holding member, a rotation shaft member, a coupling member, and an anti-rotation member. During assembly, a temporary coupling between the hub press-fitting apparatus and the liquid dynamic pressure bearing is made by screwing a threaded tap in a tap hole provided in an end face of the cylindrical member.

Abstract: A spindle motor has a rotor, a stator and a dynamic pressure bearing for supporting the rotor for rotation relative to the stator. The dynamic pressure bearing comprises a rotational shaft mounted for undergoing rotation and having a thrust bearing portion and a radial bearing portion. A bearing member rotatably supports the rotational shaft and has a closed end forming a small diameter cylinder portion for receiving the radial bearing portion of the rotational shaft and an open end forming a large diameter cylinder portion for receiving the thrust bearing portion of the rotational shaft such that first gaps for receiving a lubricating oil are formed between the rotational shaft and the bearing member. A thrust pressure member is connected to the bearing member to form a capillary seal between the rotational shaft and the open end of the bearing member and to form second gaps between the thrust pressure member and the rotational shaft for receiving a lubricating oil.

Abstract: A recording unit has an illuminating device for projecting light on an original to form an original image, and an optical device which focuses the original image formed by the illuminating device. A light control plate has a slit for allowing a portion of the original image focused by the optical device to pass through. The light which passes through the slit of the light control plate is guided onto a print head which ejects ink on a recording medium when exposed to the light.

Abstract: A spindle motor having a simplified construction with reduced axial and radial deflection while avoiding the half whirl phenomenon includes a motor frame, a rotating shaft supporting a rotor, a stator and stator coil, a permanent magnet opposing the stator, and a liquid dynamic pressure bearing. Magnetic centers of the permanent magnet and stator coil, in the axial direction of the rotating shaft, are substantially matched. The liquid dynamic pressure bearing comprises opposing surfaces of the rotating shaft and the housing. The rotating shaft has a disk-shaped thrust bearing portion disposed in a first portion of a cylindrical hole of the housing, and a radial bearing portion disposed in a second portion of the cylindrical hole. Lubricating oil fills a space between the cylindrical hole and the thrust bearing portion and radial bearing portion, and a presser ring is pressed and fixed into a third portion of the cylindrical hole to seal the bearing.

Abstract: An image recording method and apparatus employing a thermal head capable of making a sublimation type thermal transfer recording and a fusion type thermal transfer recording by means of the same thermal head. This apparatus sets its vertical printing pitch at different values in the sublimation type recording mode and the fusion type recording mode. In the sublimation type recording mode, after making a first printing, this apparatus feeds a recording paper by a distance which is an integral multiple of the vertical printing pitch and makes a second printing using the same printing data as the first printing. In the fusion type recording mode, after making a 1-line printing, this apparatus feeds the recording paper by a 1-line spacing and makes a printing by means of printing data of the next line.

Abstract: An image recording method and apparatus employing a thermal head capable of making a sublimation type thermal transfer recording and a fusion type thermal transfer recording by means of the same thermal head. This apparatus sets its vertical printing pitch at different values in the sublimation type recording mode and the fusion type recording mode. In the sublimation type recording mode, after making a first printing, this apparatus feeds a recording paper by a distance which is an integral multiple of the vertical printing pitch and makes a second printing using the same printing data as the first printing. In the fusion type recording mode, after making a 1-line printing, this apparatus feeds the recording paper by a 1-line spacing and makes a printing by means of printing data of the next line.

Abstract: A laser beam scanning device is comprised of a laser beam source for emitting a laser beam, a polygon mirror rotatable for reflecting the laser beam to deflect the same linearly in primary scanning direction and a main motor for rotating the polygon mirror. An optically converging system converges the laser beam reflected from the polygon mirror onto a photosensitive medium. A secondary scanning system includes a driving source having a pulse motor for shifting the laser beam relative to the photosensitive medium in secondary scanning direction substantially perpendicular to the primary scanning direction to thereby scan the laser beam two-dimensionally on the photosensitive medium. A controlling circuit produces a common clock signal for controlling and driving the main motor and the pulse motor according to the common clock signal.

Abstract: A simple method of manufacturing optical attenuators comprises heating a part of an optical fiber composed of a core and a cladding to a temperature around the softening point of the materials of the optical fiber and applying a tension and/or a twist to the optical fiber at a predetermined speed to form an optical attenuation area having fine cracks in the heated part of the optical fiber.