Patents by Inventor Kisaku Hasegawa

Kisaku Hasegawa 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: 4548296
    Abstract: This invention relates to a hydraulic elevator wherein working oil is transferred from a tank to a jack or vice versa by means of a hydraulic pump which is driven by an electric motor, so as to cause the elevator to ascend and descend; characterized in that a hydraulic circuit is equipped with electronically-controlled variable flow solenoid valves which set flow rates of the working oil in accordance with a program for electronic control in correspondence with respective stages of stop, slow speed ascent, full speed ascent, slow speed descent and full speed descent of the elevator.
    Type: Grant
    Filed: January 6, 1984
    Date of Patent: October 22, 1985
    Assignee: Oil Drive Kogyo, Ltd.
    Inventor: Kisaku Hasegawa