David Michael Trosclair
Engineering at Adoue St, Houma, LA

6527048, Mar 4, 2003

Feb 12, 2001

09/781463

David J. Trosclair - Houma LA 70364

E21B 1702

1662427, 1662426, 166318, 175321

A coupler system for downhole wellbore service tools comprises an elongated main body having a longitudinal bore, a plurality of release blocks disposed in slots in the main body wall, and an exterior spline about its circumference below the release blocks. The release blocks are movable radially inward and outward, and are biased inward by springs. A piston having a longitudinal bore is movably disposed within the main body bore. The piston has spaced apart larger diameter sections and a central smaller diameter section. A cylindrical washpipe body fits over the main body and has an internal spline for engagement with the main body spline, and shoulders (on the main body and on the interior of the washpipe body) limit downward movement of the washpipe body. In a first “set” position, the lower larger diameter section of the piston is adjacent the release blocks, forcing them outward against the spring bias so that the innermost ends of the release blocks are substantially flush with the inner wall of the main body bore, and the release blocks protrude from the main body outer wall and limit upward movement of the washpipe body. In a second “release” position, the central smaller diameter of the piston is adjacent the release blocks, which move inward under the spring bias so that the outmost ends of the release blocks are substantially flush with the outer wall of the main body.