Patents by Inventor Hirokazu Nishikawa

Hirokazu Nishikawa 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: 5418440
    Abstract: A position control device for a servomotor in use of a NC machine tool, a robot or the like detects a case that a control shaft is collided with something in error to stop the servomotor at a high speed so as to minimize damages of the machine. When an estimated disturbance torque estimated by a disturbance torque observer 9 is over an allowance disturbance torque, an alarm signal is outputted. At this point, a plugging control unit 11 outputs a braking torque current command in a direction of stopping the servomotor until the servomotor 5 is stopped. An operation mode determination unit 12 receives an operation mode of the machine during the operation to set the allowance disturbance torque corresponding to the operation mode to the determination unit 10. According to the present invention, the detection of the collision of the machine 6 can be performed at higher speed and a braking distance after the detection so that damages of the machine during the motor rotates at a high speed can be minimized.
    Type: Grant
    Filed: March 30, 1994
    Date of Patent: May 23, 1995
    Assignee: NEC Corporation
    Inventors: Yoshifumi Sakaguchi, Atsushi Masago, Hirokazu Nishikawa, Yasuo Hamano
  • Patent number: 4897257
    Abstract: Rapidly-disintegratable active-component-containing foamable compositions can be obtained by mixing an active component (Component-C) into a solid alkali metal or alkaline earth metal salt of carbonic acid (Component-A) and/or a solid aliphatic carboxylic acid (Component-B), and then mixing component-A and Component-B together after being moisturized separately with approx. 0.5-5% (w/w) water.
    Type: Grant
    Filed: December 2, 1988
    Date of Patent: January 30, 1990
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Hirokazu Nishikawa, Junzou Yamashita, Hiroshi Kimura