Hydraulically actuated reciprocable tools

Claim 1

IN A HYDRAULICALLY ACTUATED RECIPROCABLE IMPACT MOTOR, A CASING HAVING A BORE, A PISTON HERAD RECIPROCABLE WITHIN SAID BORE AND HAVING A SLIDING FIT THEREIN, SAID PISTON HEAD HAVING OPPOSITE FACES ALTERNATELY EXPOSABLE TO INCOMPRESSIBLE FLUID UNDER PRESSURE, OPPOSED ELONGATED FREE ENDS ON SAID PISTON HEAD, SAID ENDS BEING AXIALLY UNAFFECTED BY FLUID UNDER COMPRESSION, THE PISTON HEAD HAVING MAXIMALLY A DIAMETER 1.3 TIMES THE MINIMUM DIAMETER OF SAID ELONGATED ENDS, AN END NUMBER IN SAID CASING AT ONE END OF SAID BORE PROVIDING A SEAL BETWEEN SAID CASING AND ONE OF SAID ELONGATED ENDS, HYDRAULIC DAMPER MEANS BETWEEN SAID BORE AND SAID END MEMBER FOR ABSORBING THE ENERGY OF SAID PISTON AT THE END OF ITS STROKE IN THE DIRECTION OF SAID END MEMBER, A HIGHPRESSURE FLUID INLET AND LOW-PRESSURE FLUID OUTLET ASSOCIATED WITH SAID CASING, A FIRST TOTALLY BALANCED VALVE ASSOCIATED WITH SAID CASING IN PROXIMITY TO SAID BORE, SAID FIRST VALVE IN CONSTANT COMMUNICATION WITH SAID INLET AND BEING MOVABLE TO ALTERNATELY ADMIT SAID HIGH PRESSURE FLUID TO SAID OPPOSED PISTON FACES, A SECOND TOTALLY BALANCED VALVE ASSOCIATED WITH SAID CASING IN PROXIMITY TO SAID BORE, SAID SECOND VALVE IN CONSTANT COMMUNICATION WITH SAID OUTLET AND BEING MOVABLE TO ALTERNATELY CONNECT SAID OPPOSED PISTON FACES TO SAID LOW-PRESSURE FLUID OUTLET, A SINGLE HYDRAULIC GEAR MOTOR ASSOCIATED WITH SAID CASING, SAID GEAR MOTOR DRIVE-COUPLED TO AND SYNCHRONIZING THE MOVEMENT OF SAID VALVES, MEANS FOR HYDRAULICALLY BALANCING THE GEARS OF SAID GEAR MOTOR, AND A SINGLE PRESSURE ACCUMULATOR COUPLED BETWEEN SAID INLET AND OUTLET TO RESPOND TO PRESSURE FLUNCTUATIONS IN SAID INLET AS WELL AS IN SAID OUTLET.