Patents by Inventor Akihide Yamazaki

Akihide Yamazaki 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).

  • Pump control apparatus for hydraulic work machine, pump control method and construction machine
    Patent number: 8136355
    Abstract: A pump control apparatus for a hydraulic work machine includes: a rotation speed setting device that sets a target rotation speed for an engine; a rotation speed control device that controls an engine rotation speed so as to adjust the engine rotation speed to the target rotation speed; a first variable hydraulic pump used to drive a work hydraulic actuator, driven by the engine; a second variable hydraulic pump used to drive a cooling fan, driven by the engine; and a pump control device that controls an output flow rate of the first variable hydraulic pump and an output flow rate of the second variable hydraulic pump so as to ensure that a sum of an intake torque of the first variable hydraulic pump and an intake torque of the second variable hydraulic pump does not exceed an engine output torque determined in advance based upon the target rotation speed.
    Type: Grant
    Filed: December 18, 2006
    Date of Patent: March 20, 2012
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Gen Yasuda, Akihide Yamazaki
  • Pump Control Apparatus for Hydraulic Work Machine, Pump Control Method and Construction Machine
    Publication number: 20100218494
    Abstract: A pump control apparatus for a hydraulic work machine includes: a rotation speed setting device that sets a target rotation speed for an engine; a rotation speed control device that controls an engine rotation speed so as to adjust the engine rotation speed to the target rotation speed; a first variable hydraulic pump used to drive a work hydraulic actuator, driven by the engine; a second variable hydraulic pump used to drive a cooling fan, driven by the engine; and a pump control device that controls an output flow rate of the first variable hydraulic pump and an output flow rate of the second variable hydraulic pump so as to ensure that a sum of an intake torque of the first variable hydraulic pump and an intake torque of the second variable hydraulic pump does not exceed an engine output torque determined in advance based upon the target rotation speed.
    Type: Application
    Filed: December 18, 2006
    Publication date: September 2, 2010
    Applicant: Hitachi Construction Machinery Co., Ltd.
    Inventors: Gen Yasuda, Akihide Yamazaki