Abstract: The fluid dynamic bearing device includes a housing, two bearing sleeves fixed to the housing at positions axially spaced apart from each other, and a shaft member inserted along inner peripheries of the bearing sleeves. The housing includes a spacer portion protruding further radially inwardly than inner peripheral surfaces to which the bearing sleeves are fixed. An axial fluid path is formed in the spacer portion, and the axial fluid path communicates to flow paths formed by axial grooves of the bearing sleeves.

Abstract: The fluid dynamic bearing device includes a housing, two bearing sleeves fixed to the housing at positions axially spaced apart from each other, and a shaft member inserted along inner peripheries of the bearing sleeves. The housing includes a spacer portion protruding further radially inwardly than inner peripheral surfaces to which the bearing sleeves are fixed. An axial fluid path is formed in the spacer portion, and the axial fluid path communicates to flow paths formed by axial grooves of the bearing sleeves.

Abstract: In a radial minute gap between a substantially columnar shaft and an inner peripheral face of a substantially cylindrical sleeve, oil is retained and a radial dynamic pressure bearing is formed. A plurality of recessed portions are arranged in a circumferential direction on at least one of an outer peripheral face of the shaft and the inner peripheral face of the sleeve and a first hill portion is provided to an axial end portion of each the recessed portion. Thus, it is possible to achieve a dynamic pressure bearing with which sufficient radial shaft support can be obtained in spite of a short axial length.

Abstract: A twisted string actuator as a light-weight and space saving actuator includes a small motor and a twisted string having a structure in which two strings are twisted with each other loosely. A first end of the twisted string is connected to a finger joint, and a second end of the same is connected to a rotation shaft of the motor via a power transmission mechanism. When the rotation shaft of the motor rotates, a twisted state of the two strings of the twisted string is tightened or loosened, so that a length of the twisted string is decreased or increased. As a result, the finger joint is driven to rotate about the axis.

Abstract: A recording disk holedr hold the inner radius face of a recording disk by pressing the face only in the radial direction so that the top surface of a cover of a casing of a recording disk holding apparatus and the disk holding shoes are at the same or lower level of the top surface of a recording disk mounted on a mounting part. Grooves are formed in a contact surface of a nail portion. The grooves engage with the bumps and dips of the inner radius face of the recording disk, so that the frictional coefficient is improved and the recording disk holding force is improved.

Abstract: In a radial minute gap between a substantially columnar shaft and an inner peripheral face of a substantially cylindrical sleeve, oil is retained and a radial dynamic pressure bearing is formed. A plurality of recessed portions are arranged in a circumferential direction on at least one of an outer peripheral face of the shaft and the inner peripheral face of the sleeve and a first hill portion is provided to an axial end portion of each the recessed portion. Thus, it is possible to achieve a dynamic pressure bearing with which sufficient radial shaft support can be obtained in spite of a short axial length.

Abstract: An apparatus for recognizing a position, a diameter and a width of a cylindrical object such as a coil made of thin steel plate being wound while observed by a TV camera in unmanned manner. The coil is irradiated with laser light while the laser light is moved in the direction perpendicular to an axial direction of the coil. An image data by the laser light is obtained from a difference of image data in the case where the coil is irradiated with the laser light and in the case where the coil is not irradiated with the laser light. The image data is analyzed to obtain data such as the position and the like. In order to improve an S/N ratio of the image data, the difference signal is binarized and then integrated for a frame. Influence of the background light can be minimized and a memory capacity for the image data can be reduced.

Abstract: A method of centering a hollow cylindrical piece of work comprises measuring the outside and inside diameters and contours of the work by means of outside- and inside-diameter-measuring instruments relative to the common centerline of the instruments taken as the virtual center of the work, inputting the measured values with corrections made for any deflection of the work and for any error arising from the instruments, to an electronic computer, and allowing the computer to memorize the information and operate to find the real center of the hollow cylindrical work on the basis of the stored information, whereby the location of the real center and machining allowances necessary for obtaining a product finished to the desired contours can be be computed.