Patent ID: 6725932
Filing Date: 2004-04-27
Classification: E21B

Abstract:
A down hole jar tool comprising:a. an outer mandrel having a shoulder means, said outer mandrel also shaped to form a firing groove and a re-cock groove along the surface of its inner diameter and forming a bridge therebetween, b. a kinetic energy sleeve being disposed within said outer mandrel said sleeve positioned to be initially radically restrainable by said bridge, said firing groove and re-cock groove used to operatively engage and disengage said sleeve, c. an inner mandrel adapted to be in mechanical communication with a driving means said inner mandrel shaped to fit within said outer mandrel and to form a latching shoulder, and said inner mandrel adapted to operatively engage said shoulder to impart an upward jarring force upon said down hole jar tool, d. said kinetic energy sleeve shaped to operatively engage outer surface of said inner mandrel, being disposed between said shoulder means and a sleeve, and having an upward force communication with said sleeve, e. a reloading energy sleeve shaped to operatively engage to said outer surface of said inner mandrel and exert upward axial force on said sleeve, and f. a ring, comprising a plurality of capsule segments disposed in a generally circular arrangement and being supported in substantially immovable relation with said inner mandrel and being positioned for contact by said sleeve, in a manner that upon predetermined application of downward force to said outer mandrel and said kinetic jar energy sleeve, said firing groove being moved downwardly into registry with said sleeve to permit radial expansion of said sleeve into said firing groove and rapid downward jarring movement of said inner mandrel against said outer mandrel by said kinetic energy sleeve against said inner mandrel, and upon application of predetermined upward force to said outer mandrel and reloading energy sleeve with said sleeve in its fired condition said re-cocking groove moving upwardly into registry with said sleeve, to permit radial expansion of said sleeve into said re-cocking groove and permitting upward movement of said sleeve past said ring to the cocked position thereof.