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. 04, 2008
Filed:
Oct. 17, 2003
Bruce Mcgarian, Stonehaven, GB;
Rory Mccrae Tulloch, Aberdeen, GB;
Ian A. Gillies, Brechin, GB;
Smith International, Inc., Houston, TX (US);
Abstract
A downhole apparatus which can be used as multi-cycle circulating subs utilized in downhole drilling operations, includes a piston () slidably mounted in a body between positions in which at least one aperture in the body is opened and closed. Movement of the piston () is controlled by a pin (), secured to one of the body and a control member, and a control groove () formed in the other of the body and control member for receiving a portion of the pin. An arrangement of elements () respectively connected to the control member and body is such as to normally resist axial movement of the control member from a first axial position to a second axial position. A spring () is located in a chamber for biasing the piston (). The chamber is vented by an opening in the body.