Patents by Inventor Hidemi Iwata

Hidemi Iwata 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).

  • Hydraulic control system for a rock drill
    Patent number: 4440236
    Abstract: A rock drill having a hydraulic system for controlling striking, rotating and advancing movements of a drilling rod. The advancing or forward feeding conduit for a feed actuator is provided with a relief valve which is responsive to the pressure in the positive rotating conduit for a rotary actuator so that the pressure in the forward feeding conduit is relieved to weaken the advancing force when the load on the rotary actuator is increased. A further relief valve is also provided for relieving the pressure in the striker conduit to weaken the striking force.
    Type: Grant
    Filed: May 5, 1983
    Date of Patent: April 3, 1984
    Assignee: Toyo Kogyo Co. Ltd.
    Inventors: Takeo Shiihara, Toshihiro Niihara, Hidemi Iwata, Noboru Ishii