Patents by Inventor Zhongnan Dai

Zhongnan Dai 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).

  • Economical methods and injection apparatus for high pressure die casting process
    Patent number: 7784525
    Abstract: A method of and an apparatus for high pressure die casting are disclosed. The method uses a die casting apparatus which comprises a group of three plungers for casting metal. The two of which, injection plunger 1 and assistant plunger 3, are used to reduce metal loading time and reduce entrapped gases in die casting during a fast injection stage. By moving into injection sleeve 2, the assistant plunger separates the mold cavity 11 from the space defined by assistant plunger 3, injection sleeve 2, and injection plunger 1. The flow power device for moving said assistant plunger 3 is mounded on a back plate 8. A third plunger, the intensification plunger 12, is used to squeeze casting as soon as the injection plunger advances to a position in which the runner is separated from the closed space.
    Type: Grant
    Filed: October 24, 2007
    Date of Patent: August 31, 2010
    Inventor: Zhongnan Dai