Patents by Inventor Alan F. Lang

Alan F. Lang 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: 4823890
    Abstract: A reverse circulation deep hole rock bit that includes a drill bit connector tube telescopically extended into a drill bit housing to cooperatively form a part of a radial inner fluid channel for cuttings to flow axially outwardly and a radial outer annular clearnace space, a plurality of angularly spaced pressurized fluid passage that open to the annular space and a check valve in each fluid fluid passage to permit inward flow of fluid, but to block fluid flow in the opposite direction. A plurality of angularly spaced cutter arms have arcuate tubular segments secured to axial and radial outer portions of the arms while a radially inner tubular skirt is secured to or abuts against the axial outer portions of the arms.
    Type: Grant
    Filed: February 23, 1988
    Date of Patent: April 25, 1989
    Assignee: Longyear Company
    Inventor: Alan F. Lang