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:
Apr. 16, 1985
Filed:
Aug. 10, 1983
Thomas Jung, Isernhagen, DE;
Gerhard Heidemann, Celle, DE;
Norton Christensen, Inc., Salt Lake City, UT (US);
Abstract
A locking device for a tool with telescopically displaceable parts such as the various tools including a drilling jar used in the deep-well drilling art comprises thickened spindle portion (1) and a sleeve portion (2) with a displaceable sleeve (11) displaceable therein to and away from an axial abutment (17). The thickening of the spindle portion provided by a rigid tapered sleeve (3) with tapered end surfaces (5 and 6) and the sleeve (11) within the sleeve portion with an internal tapered surface (12) are coupled via locking balls (19) disposed for radial movement in an annular cage 20 between the rigid and displaceable sleeves 3 and 11. The sleeve (11) is held by an axial spring (16) in such a position that the balls come to lie axially between the axial abutment (17) and a region of the tapered sleeve (3) having a larger diameter and thereby form a constriction to the passage of the sleeve (3) of the spindle portion ( 11). This constriction can only be passed when the spindle and tapered sleeve (3) is pulled axially with an overload force sufficient to impress a radial force on the balls (19) which in turn forces an axial displacement of the internal tapered sleeve (11) disposed in the sleeve portion until the balls move radially sufficiently to allow passage of the larger diameter of the sleeve (3) and spindle to pass.