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:
Sep. 27, 2016
Filed:
May. 31, 2013
National Oilwell Varco, L.p., Houston, TX (US);
Preston R. Fox, Fountain Valley, CA (US);
Neil E. West, Norco, CA (US);
Lawrence E. Wells, Yorba Linda, CA (US);
National Oilwell Varco, L.P., Houston, TX (US);
Abstract
A self-aligning piston is configured to selectively engage and disengage a pipe segment to permit a top drive output shaft to be coupled to the pipe segment. In one embodiment, the self-aligning piston includes a piston body configured to rotate between a first position and a second position, at least one resilient, energy-storing member coupled to the piston body, a roller assembly coupled to the piston body, and a cam disposed between the at least one resilient, energy-storing member and the roller assembly. The resilient, energy-storing member is configured to bias the piston body into the first position by rotating the roller assembly along the cam.