Patents by Inventor Takayuki Tohya

Takayuki Tohya 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: 5134354
    Abstract: When a workpiece is cut or otherwise machined by a machine using a servo motor control apparatus having a position feedback loop, a velocity feedback loop, and a current feedback loop, it is the common practice to preset the instructed current value to a voltage corresponding to friction torque when rotation of the motor is started or reversed. This is to compensate for the response delay of the motor introduced by the friction torque. The present invention relates to improvements in this technique. After the instructed motor velocity changes from a positive value, to a negative value or vice versa, or after the detected motor velocity changes from a positive value to a nonpositive value or from a negative value to a nonnegative value, the value of the integration element of a velocity control portion is reversed according to a function. The obtained output value is added to the instructed current value or to the integration term to compensate for the response delay, thus reducing machining error.
    Type: Grant
    Filed: December 3, 1990
    Date of Patent: July 28, 1992
    Assignee: Kabushiki Kaisha Yaskawa Denki Seisakusho
    Inventors: Yoichi Yamamoto, Takayuki Tohya, Yoshiji Hiraga