The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 03, 1987
Filed:
Feb. 04, 1986
Joe R Berry, Round Rock, TX (US);
Archie L Black, Round Rock, TX (US);
William R Hamilton, Georgetown, TX (US);
Hughes Tool Company, Houston, TX (US);
Abstract
A lifting head having a gate arm, and a latch arm, pivotally secured to a frame. A clamping block, also mounted on the frame, is movable between a retracted position away from the drill collar and an extended position against the drill collar. A plurality of gripping inserts are located on the clamping block and on the gate arm. Each insert has a body and a plurality of teeth. The bodies of the inserts may be vertical or angled, but the teeth of the inserts are mounted in a spiral. This allows the inserts to grip the drill collar, even if the lifting head grips the collar at a place having a spiral groove.