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:
Jul. 05, 1983
Filed:
May. 20, 1981
James T Aumann, Salt Lake City, UT (US);
Christensen, Inc., Salt Lake City, UT (US);
Abstract
A multi position safety valve retainable within an internal portion of a drill string casing (s) and responsive to the greater differential pressure in an internal fluid passage to displace a valve head (32) relative to a valve seat (VS) from its normal partially open position to either a wide open or a closed position. The valve head (32) is attached to a valve stem (30) that extends through a valve chamber and slideably mounted in opposite closed ends of a valve body and returnable to and maintained in the partially open position by opposing compression springs (34) (36) situated between opposite ends (22) of the valve body (VB) and one side of an intermediate abutment (30c) of the valve stem (30) and an intervening disc (38) on the opposite side thereof. The disc 38 is moveable into and out of seating engagement with an intermediate stop (20a) by one spring (34) and the intermediate abutment (30c) of the valve stem respectively.