Patents by Inventor Paul H. Hewitt

Paul H. Hewitt 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: 5921333
    Abstract: A drill bit casting comprising a casting material, an insert having a base, a tip and a side wall surface, and a sleeve including a bottom wall, a peripheral side wall and a chamber formed within the side wall. The base of the insert is located within the chamber of the sleeve such that the peripheral side wall of the sleeve extends around and engages the side wall of the insert and such that the tip of the insert protrudes from the chamber beyond the side wall of the sleeve. The casting material is cast around and contacts the exterior surface of the sleeve. The sleeve insulates the insert from direct contact with the casting material such that the insert remains below its sinter temperature during the casting process.
    Type: Grant
    Filed: August 6, 1997
    Date of Patent: July 13, 1999
    Assignee: Naco, Inc.
    Inventor: Paul H. Hewitt