Abstract: A disk assembly, which includes a large number of magnetic disks arranged in layers on a disk loading hub, is detachably mounted on a rotating shaft of an air spindle motor that is set on a base. The base has thereon a movable table capable of reciprocation. The movable table carries thereon a rotary positioner for rotating and positioning a stacked head assembly, which is formed of a large number of magnetic heads stacked in layers, and a plurality of ramps for loading into and unloading the magnetic heads from the magnetic disks. The distance between the respective rotating shafts of the air spindle motor and the rotary positioner can be adjusted by moving the movable table.

Abstract: A controller rotates, using a spindle motor, a first disk medium and at least one second disk medium in a state in which the first and second disk mediums are stacked. In this state, the controller controls a VCM on the basis of first head positioning information read by a first head from the first disk medium. As a result, a carriage that supports the first and second heads is driven to position the first and second heads in respective target radial positions on the first and second disk mediums. The controller causes the second head to write second head positioning information to the second disk medium, while changing the target radial position in increments of a predetermined pitch.

Abstract: A disk drive is provided which uses a disk having a maximal limit cylinder group formed based on an initially recorded servo data before being assembled in a drive body. A CPU sets an actually usable data recording area on the disk by seeking the head in a radial direction over the disk. Further, the CPU allows the generation of a translation table for obtaining a correspondence between inherent physical cylinder address information of an effective cylinder group contained in the set data recording area and logical cylinder address information set to identify the effective cylinder group and allows the translation table to be stored in a memory. The CPU refers to the translation table when, in response to an access request from a host system, control is made to position a head to a target position, and finds physical cylinder address information corresponding to the target cylinder.

Abstract: A disk drive is provided which uses a disk having a maximal limit cylinder group formed based on an initially recorded servo data before being assembled in a drive body. A CPU sets an actually usable data recording area on the disk by seeking the head in a radial direction over the disk. Further, the CPU allows the generation of a translation table for obtaining a correspondence between inherent physical cylinder address information of an effective cylinder group contained in the set data recording area and logical cylinder address information set to identify the effective cylinder group and allows the translation table to be stored in a memory. The CPU refers to the translation table when, in response to an access request from a host system, control is made to position a head to a target position, and finds-physical cylinder address information corresponding to the target cylinder.

Abstract: To prevent adverse effect, on machining accuracy, of cogging thrust of linear motors when used in a combined linear motor driving a machine tool. Three linear motor movers are fixedly attached to a moving table of a machine tool, while three linear motor stators are fixedly attached to a base. The three linear motors are driven in parallel to thereby drive the moving table. The respective linear motor stators are fixed to the base so as to have fixed phases relative to the base, stepwisely displaced by an electrical angle 60° whereby cogging thrust is leveled in the entire combined linear motor.

Abstract: A disk assembly, which includes a large number of magnetic disks arranged in layers on a disk loading hub, is detachably mounted on a rotating shaft of an air spindle motor that is set on a base. The base has thereon a movable table capable of reciprocation. The movable table carries thereon a rotary positioner for rotating and positioning a stacked head assembly, which is formed of a large number of magnetic heads stacked in layers, and a plurality of ramps for loading into and unloading the magnetic heads from the magnetic disks. The distance between the respective rotating shafts of the air spindle motor and the rotary positioner can be adjusted by moving the movable table.

Abstract: An eccentric-shape machining apparatus as well as an eccentric-shape machining method are provided which can efficiently and accurately bore, contour or thread a workpiece about any position other than the rotational center of the workpiece. The workpiece is rotatably driven while controlling the rotational phase of the workpiece. A rotating tool spindle adapted to mount a cutting tool is rotatably driven while controlling the rotational phase of the rotating tool spindle. The rotating tool spindle is mounted on a cutting head which is controllably fed and positioned in Z-axis extending parallel to X-axis perpendicular to the axis of the rotating tool spindle. During one complete revolution of the workpiece, the rotational phases of the main spindle and rotating tool spindle and the movement of the cutting head in the X-axis direction are simultaneously controlled such that the cutting tool is brought into contact with the inner and outer peripheries of the workpiece by a given depth of cut.

Abstract: A disk system has a disk as a recording medium, and a disk recording/reproducing apparatus for recording and reproducing data by a head radially movable provided on a disk by a head moving mechanism, and the disk has a first region formed with a servo sector having servo information along a data track for recording and reproducing data on a disk, second regions having servo sectors having servo information along a servo track and of the number of magnification of integer number of the servo sectors in the first region, and the disk recording/reproducing apparatus has, position detecting section placed on the moving portion of the head moving mechanism for detecting the moving position of a head to output a position signal representing the head position in the radial direction of the disk, memory section for storing "head follow-up information" for a servo track obtained from the position signal in the state that the head is positioned on the servo track, and section for controlling to follow up the head to th

Abstract: A magnetic or optical disk apparatus having a flexible disk rotated at high speed and head sliders for reading and writing information on the disk, floating from both sides of the disk. The disk apparatus is also provided with straightening plates for keeping air flow in the radial direction of the disk as a laminar flow to surely prevent the disk from being vibrated at the time when the disk is rotated at high speed. As the result, positions of the head sliders relative to the disk can be surely and accurately maintained to provide heads with excellent recording and reproducing characteristics. Mass storage and high speed access can be thus achieved without damaging the flexible disk and the disk apparatus can be smaller-sized with lighter weight and lower cost.

Abstract: For machining male or female screws, especially of considerably large size diameter, variable pitch or tapered, as desired, a machining center is used which is composed of a work table mounting the work fixedly thereon, and a rotatable machining spindle exchangeably fitted with a thread-cutting tool. Axial feed and rotational speed of the spindle are driven by respective drive motors. In addition, the work table is fed bilaterally on a plane perpendicular to the axis of the spindle by respective feed motors. All these four motors are controlled synchronously by respective controllers which are subjected to control by a single parent numerical controller.

Abstract: For machining male or female screws, especially of considerably large size diameter, variable pitch or taper, as desired, a machining center is used which is composed of a work table mounting the work fixedly thereon, and a rotatable machining spindle exchangeably fitted with a thread-cutting tool. Axial feed and rotational speed of the spindle are driven by respective drive motors. In addition, the work table is fed bilaterally on a plane perpendicular to the axis of the spindle by respective feed motors. All these four motors are controlled synchronously by respective controllers which are subjected to control by a single parent numerical controller.

Abstract: A magnetic or optical disk apparatus having a flexible disk rotated at high speed and head sliders for reading and writing information on the disk, floating from both sides of the disk. The disk apparatus is also provided with straightening plates for keeping air flow in the radial direction of the disk as a laminar flow to surely prevent the disk from being vibrated at the time when the disk is rotated at high speed. As the result, positions of the head sliders relative to the disk can be surely and accurately maintained to provide heads with excellent recording and reproducing characteristics. Mass storage and high speed access can be thus achieved without damaging the flexible disk and the disk apparatus can be smaller-sized with lighter weight and lower cost.