Directional drill with hydraulically extended shoe

Claim 1

A DIRECTIONAL DRILLING SYSTEM FOR DEFLECTING A DRILL BIT FORM THE CENTER LINE OF A BORE HOLE MEANS ACTUATED BY THE PRESSURE OF A DRILLING LIQUID, WHICH SYSTEM INCLUDES: A TABULAR MANDREL FORMING A PART OF THE DRILL STRING NEAR THE DRILLING BIT, SAID MANDREL HAVING AN AXIAL PASSAGE FOR CONDUCTING DRILLING LIQUID UNDER PRESSURE FROM THE INTERIOR OF THE DRILL ABOVE IT OT THE DRILL BIT; A HYDRAILIC SYSTEM HOUSING ENCLOSING A HYDRAULIC FLUID RESERVOIR, SAID HOUSING BEING COUPLED TO SAID MANDREL; A DISTENSIBLE BLADDER FORMING A CONDUIT PASSING THROUGH SAID HYDRAULIC RESERVOIR CHAMBER AND FORMING PART OF A DRILLING LIQUID PASSAGE THROUGH SAID HYDRAULIC SYSTEM HOUSING; AN ANNULAR PISTON RECIPROCABLE ON SAID TABULAR MANDREL ADJACENT SAID HYDRAULIC SYSTEM HOUSING; WALLS INTEGRAL WITH SAID HYDRAULIC SYSTME HOUSING FORMING A CYLINDER ENCLOSING ONE END OF SAID ANNULAR PISOTN, AND PROVIDING AN ANNULAR HYDRAULIC ACTUATING CHAMBER FOR ACTUATING SAID PISTON, SAID HYDRAULIC ACTUATING CHAMBER BEING IN OPEN COMMUNICATION WITH SAID HYDRAULICH RESERVOIR CHAMBER BUT SEPARATE FROM THE DRILLING LIQUID PASSAGE THROUGH SAID HYDRAULIC RESERVOIR BY SAID BLADDER; A BEARING OF THE ANTIFRICTION TYPE HAVING ITS INNER RACE RECIPROCABLE AND ROTATAABLE WITH SAID ANNULAR PISTON, AND ITS OUTER RACE RECIPROCABLE WITHOUT ROTATION; A RECIPROCABLE STRUCTURE MOUNTED ON THE OUTER RACE OF SAID RECIPROCABLE BEARING; A HELICAL SPRING ENCIRCLING SAID TABULAR MANDREL FOR A PART OF ITS LENGTH ADJACENT SAID RECIPROCAL BEARAINGS, AND URGING SAID ANNULAR PISTON INTO SAID HYDRAULIC ACTUATING CHAMBER BY THRUST TRANSMITTED THROUGH THE INNER RACE OF SAID RECIPROCABLE BEARING; ANCHORING MEANS FOR ANCHORING THE END OF SAID HELICAL SPRING OPPOSITE SAID RECIPROCAL BEARING TO SAID TABULAR MANDREL. TO CONSTRAIN SAID HELICAL SPRING TO LONGITUDINAL COMPRESSION WHEN SAID PISTON IS EXPELLED FROM SAIOD HYDRAULIC CYLINDER; A RECIPROCABLE STRUCTURE MOUNTED ON THE OUTER RACE OF SAID RECIPROCABLE BEARING AND RECIPROCAL THEREWITH; A NON-RECIPROCATING BEARING MOUNTED ON SAID TABULAR MANDREL AT A POINT SPACED FROM SAID RECIPROCABLE BAERING, AND HAVING ITS INNER RACE ROTATABLE WITH SAID TABULAR MANDRE, AND ITS OUTER RACE ROTATIONALLY FREE OF MANDREL ROTATION; A LONGITUDINALLY EXTENDED SHOE FOR ENGAGING THE SIDEWALL OF SAID BORE HOLE, SAID SHOE HAVING A RECTRACTED REST POSITION ADJACENT SAID TABLUALR MANDRE, AND AN EXTENDED DRILLING POSITION SPACED FROM SAID TABULAR MANDREL TOWARD THE SIDEWALLS OF SAID BORE HOLE STATIONARY STRUCTURE SUPPORTED ON THE OUTER RACE OF SAID NON-RECIPROCABLE BEARING AND ADAPTED TO REMAIN RELATIVELY FREE OF RECIPROCATION AND ROTATION DURING ROTATION OF SAID TABUALR MANDREL; HOLDING LINK MEANS BETWEEN SAID STATIONARY STRUCTURE AND SAID SHOE FOR PREVENTING SAID SHOE FROM MOVEMENT LONGITUDINAL TO SAID TABUALR MANDREL WITH SAID RECIPROCABLE STRUCTURE; AND LINK MEANS BETWEEN SAID RECIPROCABLE STRUCTURE AND SAID SHOE FOR THRUSTING SAID SHOE OUTWARD FROM ITS REST POSITION TO ITS BORE HOLE WALL ENGAGING POSITION UPON DISPLACEMENT OF SAID RECIPROCABLE STRUCTURE BY MOVEMENT OF SAID HYDRAULIC PISTON PARTIALLY OUT OF SAUD HYDRAULIC ACTUATING CHAMBER.