Abstract: A card reader includes readers facing each other, and each one the readers can read information from plural tracks respectively. The card reader further includes a detector for detecting a type of information read by a magnetic head; two magnetic heads; decoders coupled to each one of the tracks respectively; storage sections for storing information decoded. The detector is coupled to every storage section, and controls an output of the information stored in the respective storage sections depending on a type of the information. Information is stored in a magnetic card, and out of the information read by the tracks of the two magnetic heads, only the necessary magnetic card information can be made valid.

Abstract: A position control system for a disk storage drive system which includes a data transducer for recording and playback of the information stored in a desired data track of an information storage disk having a plurality of data storage tracks thereon, includes: a driver unit for actuating the data transducer; a position encoder of detecting a variation in movement of the data transducer and for producing a current position signal thereof; a tracking error detector for producing a tracking error signal upon detecting a positional difference of the data transducer from the desired data track; a track deflection estimator for estimating a deflection of track resulting from either eccentricity or undulation of the data track and for generating a feed-forward signal based on the estimation, and a discrete-time control loop for controlling the driver unit in accordance with the tracking error signal.

Abstract: A position control system is disclosed for positioning a stepping motor to a target position according to a closed loop control system. The closed loop control system controls the position of the stepping motor according to a current position signal outputted from an encoder operatively coupled to the stepping motor. Furthermore, circuitry is provided for correcting electrically a torque angle error of the stepping motor caused by a positional error between the stepping motor and the encoder due to a mechanical mounting error of the encoder, to thereby drive the stepping motor at a torque angle maintained at the most desirable range.

Abstract: A data transducer position control system for data disk storage drive system involves an electronically and mechanically improved method and apparatus for position control of the data transducer adapted to write and/or read information data in and/or from the data tracks provided on a data disk. Particularly, the system comprises a positioning device for actuating the data transducer, a position encoder for detecting the position of the data transducer, a tracking error detector for detecting the relative position of the data transducer to the selected data track, and compensating position calculator for precise tracking so that the speed-up of track access can be effected, that the accuracy in positioning can be improved, that the system itself can be compact in size and reduced in energy consumption, and that the control electronic system can also be simple in arrangement.

Abstract: A magnetic detector of the present invention employs magneto-resistive elements and detects magnetic teeth of an object to be detected, and more particularly, a constant DC magnetic field is supplied to the magneto-resistive elements in such a way so as to avoid a non-linear region of the DC magnetic field to permit the use of such elements in the region exhibiting good linearity. The present invention provides the DC magnetic field to the magneto-resistive elements by employing a simple structure wherein the magneto-resistive elements are arranged inclined relative to the magnetic field defined between a permanent magnet and the magnetic teeth. Furthermore, the magneto-resistive elements having two phases delayed by .pi./2 are used in a half-bridge so as to improve the stability, waveform distortion, etc. with respect to the temperature of the detected signal.

Abstract: A two-axis positioning system comprising three linear motors, two of which are spaced at a predetermined interval and disposed movably in the direction of a first axis and another one of which is supported by two motors and made movable in the direction of a second axis, the three motors having position control loops independent of or related with each other corresponding to input movement command signals in the directions of the first and second axes.

Abstract: A linear motor comprising; a pair of iron cores with plural magnetic teeth groups in which phase is shifted 180 degrees in the direction of its movement, a movable element in which groups of magnetic teeth on the same iron core have the same phases, plural rows of magnetic teeth positioned crossing the direction of the movable element's movement at right angles and a fixed element in which mutual phase is shifted as much as n/m.multidot.P (m is the number of phases of the linear motor, n is an integer where m>n and P is the pitch of magnetic teeth).