Patents by Inventor Miao Jiahua

Miao Jiahua 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: 7900493
    Abstract: A closed forging die and a forging method with which sagging can be reduced, a constant velocity joint and a universal joint can be made compact and lightweight, removal of a shaft tip thereof by machining prior to heat treatment is not required, and material costs and machining costs can be reduced by using a closed forging die includes openable dies, and punches that move in an opening/closing direction of the dies to pressurize a material in the dies. By using the die, a product having shaft portions formed radially is manufactured. A clearance is provided to each of the formed shaft portions between a tip surface, and abutting portions are provided to the dies side abutting against at least a tip side of an outer circumferential surface of the shaft portions.
    Type: Grant
    Filed: January 7, 2008
    Date of Patent: March 8, 2011
    Assignee: NTN Corporation
    Inventors: Miao Jiahua, Akira Sera, Nobuo Suzuki
  • Publication number: 20080184765
    Abstract: The present invention provides a closed forging die and a forging method with which sagging can be reduced, a constant velocity joint and a universal joint can be made compact and lightweight, remove of a shaft tip thereof by machining prior to heat treatment is not required, and material costs and machining costs can be reduced. The closed forging die according to the present invention includes openable dies (11, 12), and punches (14, 15) that move in an opening/closing direction of the dies (11, 12) to pressurize a material in the dies (11, 12). By using the die, a product (16) having shaft portions (17) formed radially is manufactured. A clearance (26) is provided to each of the formed shaft portions (17) between a tip surface (17a), and abutting portions (25) are provided to the dies side abutting against at least a tip side of an outer circumferential surface of the shaft portions (17).
    Type: Application
    Filed: January 7, 2008
    Publication date: August 7, 2008
    Inventors: Miao Jiahua, Akira Sera, Nobuo Suzuki