Differential area motor for fluid actuated fastener driving machines

Claim 1

A FLUID ACTUATED FASTENER DRIVING MACHINE COMPRISING A HOUSING HAVING A PISTON SLEEVE, AN ACTUATING VALVE SLEEVE AND A CONTROL VALVE SLEEVE, A PISTON RECIPROCATINGLY MOVABLE WITHIN SAID PISTON SLEEVE, SAID PISTON HAVING A DRIVING SURFACE DIVIDED INTO A FIRST ELEMENT AND A SECOND ELEMENT AND A RETURN SURFACE OF SMALLER OPERATIONAL AREA THAN SAID DRIVING SURFACE, FASTENER DRIVING MEANS OPERATIVELY CONNECTED TO SAID PISTON AT ITS LOWER PORTION FIRST CONDUIT MEANS FOR PRESSURE FLUID WITHIN SAID HOUSING COMMUNICATING WITH THE RETURN SURFACE OF SAID PISTON, SECOND CONDUIT MEANS FOR PRESSURE FLUID WITHIN SAID HOUSING COMMUNICATING WITH THE FIRST PORTION OF THE DRIVING SURFACE OF SAID PISTON, A CIRCUMFERENTIAL MOVABLE CONTROL VALVE MEMBER SLIDABLY MOVABLE WITHIN SAID CONTROL VALVE SLEEVE AND ALSO LOCATED WITHIN SAID SECOND CONDUIT MEANS AND NORMALLY BLOCKING ADMISSION OF PRESSURE FLUID TO THE FIRST ELEMENT OF THE DRIVING SURFACE OF SAID PISTON, FIRST SPRING MEANS ABOVE SAID CONTROL VALVE MEMBER NORMALLY HOLDING SAID MEMBER IN BLOCKING POSITION, ACTUATING VALVE MEANS WITHIN SAID ACTUATING VALVE SLEEVE, SAID ACTUATING VALVE MEANS INCLUDING A SLIDER MEMBER THEREWITHIN MOVABLE TO ENGAGED AND DISENGAGED POSITIONS AND PROVIDED WITH A FIRST RECESS AND A CONTIGUOUS WIDER SECOND RECESS, A BALL NORMALLY SEATED AT THE JUNCTION BETWEEN SAID FIRST AND SECOND RECESSES, A STEM MEMBER NARROWER THAN SAID FIRST RECESS AND NORMALLY EXTENDING THEREWITHIN SHORT OF SAID BALL, AND A SECOND COIL SPRING MEMBER ABOUT SAID STEM ABUTTING SAID SLIDER, SAID ACTUATING VALVE SLEEVE PROVIDED WITH FIRST, SECOND, AND THIRD OPENING, SAID FIRST OPENING BEING OPEN TO ATMOSPHERE, SAID SECOND OPENING NORMALLY COMMUNICATING WITH THE DRIVING SURFACE OF SAID PISTON, AND SAID THIRD OPENING NORMALLY COMMUNICATING WITH SAID SECOND RECESS AND SAID SECOND CONDUIT MEANS; MOVEMENT OF SAID SLIDER TO ENGAGED POSITION BLOCKING SAID SECOND AND THIRD OPENING OF SAID ACTUATING VALVE MEANS AN UNSEATING SAID BALL SO THAT SAID CONTROL VALVE MEMBER IS RAISED AND PRESSURE FLUID CONTACTS THE FIRST ELEMENT OF THE DRIVING SURFACE OF SAID PISTON SO AS TO DRIVE SAID PISTON DOWNWARDLY AND RELEASE OF SAID SLIDER TO DISENGAGED POSITION RE-SEATS SAID BALL AND UNBLOCKS SAID SECOND AND THIRD OPENINGS OF SAID ACTUATING VALVE MEANS, THUS LOWERING SAID CONTROL VALVE MEMBER AND EXHAUSTING THE PRESSURE FLUID IN CONTACT WITH SAID SAID FIRST ELEMENT OF SAID DRIVING SURFACE OF SAID PISTON SO THAT SAID PISTON RETURNS TO ITS NORMAL POSITION AND MEANS FOR CLOSING SAID CONTROL VALVE OPERATIVELY CONNECTED WITH SAID PISTON AND CLOSING SAID CONTROL VALVE WHEN SAID PISTON TRAVELS TO NORMAL POSITION.