Patents by Inventor Hirofumi Kita

Hirofumi Kita 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).

  • Motor operation controller and insulation type bidirectional DC voltage converter
    Patent number: 6335871
    Abstract: A motor operation controller, which can accommodate different power supply voltages by changing a minimum circuit configuration using common motors, wiring, etc., has an insulation structure between input power supply and the motors for providing the capability of bidirectional operation in a power mode and a regeneration mode. The motor operation controller comprises a converter section and an inverter section for supplying power to a motor. In the converter section, there is an insulation type bidirectional DC voltage conversion function provided by an insulation type bidirectional DC voltage conversion section 32 having an insulation type bidirectional DC voltage converter 33, a controller 35, and a smoothing circuit 34.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: January 1, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hirofumi Kita, Toshiyuki Kaitani, Masahiro Kimata, Yoshitaka Ohnishi
  • Mutual connecting apparatus between networks
    Patent number: 5640400
    Abstract: A gateway as one example of a mutual connecting appraratus between networks virtually provides an address of a mini manufacturing automation protocol (miniMAP) device to a mechatronics network (ME-NET) device in plural devices forming a network so that the miniMAP device uniquely identifies the ME-NET device. These plural devices connected to respective networks can mutually transmit and receive data in a network environment in which the ME-NET device is connected to the miniMAP device or another ME-NET device. Conversely, an address of the ME-NET device may be virtually provided to the miniMAP device so that the ME-NET device uniquely identifies the miniMAP device. Further, for example, the plural devices may be constructed by ME-NET devices. In this case, one ME-NET device uniquely identifies another ME-NET device in the plural ME-NET devices by virtually providing a station address unused in this one ME-NET device to this another ME-NET device.
    Type: Grant
    Filed: February 27, 1996
    Date of Patent: June 17, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Ryoichi Sato, Hirofumi Kita, Kouiti Matuo, Masahiko Tsukamoto, Ikuya Suwa, Hideto Naraki, Noriyuki Takao, Hidetoshi Takano
  • Spindle drive system of machine tool
    Patent number: 5079490
    Abstract: A spindle drive system of a machine tool, wherein a control mode changeover section of a control unit selects one of both a speed control mode for controlling a rotational speed of a spindle through negative feedback of the rotational speed of the spindle and a position control mode for controlling a rotational position of the spindle through negative feedback of the rotational position of the spindle, and a gain changeover section changes speed loop and position loop gains to a greater value during cutting operation than during non-cutting rapid feed operation when the position control mode has been selected.
    Type: Grant
    Filed: September 13, 1990
    Date of Patent: January 7, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hirofumi Kita, Takahiro Hayashida