Patents by Inventor Changeuk Zhang

Changeuk Zhang 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: 5921887
    Abstract: A hydraulic control system for automatic transmission, which has a plurality of friction elements for selectively transmitting rotational force of a torque convertor to gear elements therein, controls engagement of the plurality of friction elements in proportion to forward and reverse speeds by operation of a plurality of valves for regulating, controlling and distributing hydraulic fluid supplied by an oil pump. The hydraulic control system includes a manual valve moving based on operation of a shift select lever by a user to select an operation range. The manual valve controls the supply of hydraulic fluid to at least one of the plurality of valves such that the hydraulic fluid generated by the oil pump is used as lubricating fluid for the torque convertor when the shift select lever is in a park operation range.
    Type: Grant
    Filed: June 20, 1997
    Date of Patent: July 13, 1999
    Assignee: Hyundai Motor Company
    Inventor: Changeuk Zhang