Release Mechanism for a Jarring Tool

Abstract

A release mechanism for a jarring tool is formed by a plurality of segmented release lugs. Each lug includes a plurality of axial spaced projections on an inner surface and a plurality of grooves on an outer surface. The projections may have either different widths or may be separated by varying distances and releaseably engage corresponding grooves in a mandrel located within a housing of the tool. The release lugs are positioned between a trigger sleeve and the mandrel. In one embodiment, the release lugs are positioned within a support collar. In a second embodiment, the lugs are provided with stabilizing posts and cavities that serve to maintain the lugs in a proper alignment.

1 . A release mechanism for a jarring tool comprising;
 a) a plurality of release lugs forming an annular array,   b) each release lug including at least one cavity and at least one post adapted to interact with cavities and posts of adjacent lugs, and   c) an annular trigger sleeve surrounding the lugs.   
     
     
         2 . The release mechanism of  claim 1  wherein the release lugs are spaced apart from each other in the annular array. 
     
     
         3 . The release mechanism of  claim 1  further including a plurality of springs surrounding the lugs. 
     
     
         4 . The release mechanism of  claim 1  wherein each lug includes a plurality of ridges and grooves on an outer surface thereof adapted to interact with a plurality of ridges and grooves on an inner surface of the annular trigger sleeve. 
     
     
         5 . The release mechanism of  claim 4  wherein each release lug includes a plurality of ridges and grooves on an inner surface thereof.