Patents by Inventor Jiro Yamada

Jiro Yamada has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4512010
    Abstract: A control system for a linear tracking arm in a record player. A signal representative of a tracking error angle of the arm is, after A/D conversion, supplied to a microprocessor for producing a control signal which controls an arm drive device so that the tracking error angle constantly remains zero. For invalidating an offset quantity possibly produced in the output of a tracking error angle detecting sensor due to changes in the characteristic thereof, a signal produced by the sensor when the arm is lifted in precedence to the playback operation is stored in a memory of the microprocessor. During the playback, the tracking error angle is detected with reference to the stored value. An average moving speed of the arm is measured for discriminating transient increasing in the speed of the arm caused by eccentricity of the disc from the increasing of the speed caused by the arm entering a lead-out groove of the disc.
    Type: Grant
    Filed: September 24, 1982
    Date of Patent: April 16, 1985
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Jiro Yamada, Tetsuo Maeda, Hiroshi Yasuda