Patents by Inventor Allan J. Hewett

Allan J. Hewett 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 circuit flow control
    Patent number: 5329767
    Abstract: A hydraulic system incorporating a double acting piston and cylinder and a bi-directional pump/motor derives energy from a drive system when operating in the pump mode and delivers energy to the drive system when in the pump mode and includes a circulation valve for supplementing fluid flow to and from and fluid supply in accordance with the unequal demands of the chambers driving the hydraulic actuator in one direction or the other by circulating fluid between the chambers.
    Type: Grant
    Filed: January 21, 1993
    Date of Patent: July 19, 1994
    Assignee: The University of British Columbia
    Inventor: Allan J. Hewett