Patents by Inventor C. L. Hill

C. L. Hill 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).

  • Method of replacing drill bit heads
    Patent number: 4817852
    Abstract: A method of joining impact or cutting heads to the shanks of down-the-hole rock drilling bits utilizing inertia welding techniques wherein the interfacing portions of the heads and shanks are structured to provide appropriate flash relief areas adjacent generally planar and abutting contact surfaces of the heads and shanks so as to promote the thorough and continuous diffusion bonding of the components across the total area of such contact surfaces.
    Type: Grant
    Filed: October 8, 1987
    Date of Patent: April 4, 1989
    Assignee: T. H. Industries
    Inventor: C. L. Hill