Abstract: A dynamic-pressure gas bearing structure includes a columnar shaft made of a silicon-nitride-based ceramic sintered body, a hollow cylindrical sleeve opposed to the shaft as keeping a clearance in a radial direction, the sleeve being made of a silicon-nitride-based ceramic sintered body, and at least three flat face portions located on a peripheral surface of the shaft and at equal intervals to the circumference along the peripheral surface. The flat face portion includes a plurality of unit planes continuously formed at predetermined angles to a direction of the circumference on the peripheral surface of the shaft. The unit planes are formed so as to extend substantially in parallel with an axial direction of the shaft.

Abstract: A scanning motor includes a fixed shaft made of a ceramic material. The rotary sleeve is rotatably fitted onto the material, and a rotary sleeve also made of a ceramic fixed shaft so as to be rotatable about the fixed shaft. The motor further includes a thrust plate fixed to one end portion of the rotary sleeve. At least an abutting surface of the thrust plate faces an end surface of the fixed shaft. The motor further includes a driver for rotating the fixed sleeve. At least one of the end surface of the fixed shaft and the abutting surface of the thrust plate has the shape of at least a part of the surface of a sphere. A fixing member, made of a metal material, can be fixed around the rotary sleeve and a rotary polygonal mirror and a driving magnet can be fixed to the fixing member.

Abstract: A dynamic fluid bearing rotating apparatus comprises a shaft, a sleeve rotatably fitted to the shaft, a fixed member formed of a resin material, the fixed member being molded integrally with the sleeve, and a driver for rotating the shaft.

Abstract: A deflection scanner has a container for accommodating a deflector and lens. The deflector is adapted to be rotated by a driving motor which is supported by a bearing so as to deflect and scan a light beam emitted from a light source. The housing of the driving motor is fixed on the container by use of an elastic member instead of screws.

Abstract: A resist 4 is printed on the areas where the dynamic pressure generating grooves 2 are to be formed, on curved surface of a shaft core member 1a. After the resist 4 is hardened by baking, hard electroless plating is conducted to form a plated layer 3 of a thickness equal to the depth of the grooves 2. Then the resist 4 is removed to obtain a shaft 1 with dynamic pressure generating grooves 2. The dynamic pressure during rotation is free from fluctuation as the dynamic pressure generating grooves are highly precise and constant in the depth and in the cross-sectional shape.

Abstract: A light deflecting apparatus for deflecting a light flux are provided with a shaft, a deflector, a sleeve, a projecting member and driving device. The deflector is attached to the shaft and is adapted to deflect the light flux. The sleeve is rotatably fitted to the shaft and has a concave portion in a portion which is fitted to the shaft. The projecting member is adapted to be fitted into the concave portion of the sleeve. The shaft is rotated by the driving device. By such the construction, it is prevented that the deflector attached to the shaft is lifted up or pulled out from the fixed member than it is needed.

Abstract: A hydrodynamic bearing system comprises a shaft, a sleeve rotatably fitted on the shaft and a thrust plate fixed to the sleeve and acting to support one end of the shaft in a thrust direction. First shallow grooves are formed in at least one of fitted surfaces of the shaft and of the sleeve to support one of the shaft and the sleeve with respect to the other in a radial direction, and a second shallow groove is formed in at least one of the shaft and the thrust plate with respect to the other in a thrust direction. The thrust plate is made of material including resin material as a main component and has an outside periphery portion with a thickness thicker than that of an inside periphery portion thereof.

Abstract: A motor supported by a dynamic pressure fluid bearing supporting a rotatable member by the dynamic pressure of fluid created by rotation is hermetically sealed with respect to the outside. The motor further includes a fixed shaft with the grooves and a rotatable sleeve. The rotatable sleeve is engageable with the fixed shaft and an optical member are mounted on the rotatable shaft.

Abstract: A dynamic pressure bearing device a relatively rotatable shaft member and sleeve member, accommodating the shaft member, are relatively supported with respect to a thrust direction and a radial direction, and wherein there is provided a circulation passageway for circulating a fluid along at least a part of a thrust surface between the shaft member and the sleeve member.

Abstract: A conveyor device for alignment in which minutely displaceable members and hydraulic fluid supply pads are disposed between a slide and a guide. The relative position of the slide and the guide is adjusted by controlling the dimension of the minutely displaceable members.

Abstract: There is disclosed a static pressure bearing which is provided with plural fluid supplying pads for supplying a fluid in a gap between a guide member and a bearing member whereby the ratio of the change of pressure of the fluid supplied from the pads to the change in the gap is regulatable.

Abstract: In making reflection mirrors for optics, a technique is provided for making up a reflection mirror not of a glass-system material but of metallic material, and a method for high-precision mirror-machining of a metal plate is also disclosed.

Abstract: An elastic roller composed of an axial core member and an elastic, liquid retentive layer of foam structure with uniform layer thickness surrounding the circumference of said core member, said elastic roller further comprising a flexible, liquid permeable member in the form of a cylinder or sleeve having an inner diameter smaller than the outer diameter of said roller, said flexible member being disposed to cover the circumference of said roller and having extensions extending beyond both side ends of said roller and being shrunk along the ends of said elastic foam structure layer at both sides, respectively, so as to cover also said side ends of the layer with said flexible member. A method of making the elastic roller is also disclosed.

Abstract: An elastic roller composed of an axial core member and an elastic, liquid retentive layer of foam structure with uniform layer thickness surrounding the circumference of said core member, said elastic roller further comprising a flexible, liquid permeable member in a form of cylinder or sleeve having an inner diameter smaller than the outer diameter of said roller, said flexible member being disposed to cover the circumference of said roller and having extensions extending beyond the both side ends of said roller and being shrunk along the ends of said elastic foam structure layer at the both sides respectively so as to cover also said both side ends of the layer with said flexible member. A method of making the elastic roller is also disclosed.