Digital hydraulic positioning device

Claim 1

IN A MACHINE TOOL HAVING WORKPIECE CARRYING MEANS, AND AUTOMATIC MEANS CONTROLLED BY THE POSITION OF A DRIVEN PISTON FOR CONTROLLING POINT-TO-POINT LOCATIONS INTO WHICH THE WORKPIECE IS CARRIED BY THE CARRYING MEANS: A DRIVEN PISTON WHICH ON THE DRIVE STROKE IS DISPLACED FROM AN INITIAL STARTING POSITION TO A SELECTED POSITION THEREFROM AND THEN RESTORED ON THE RETURN STROKE; A CONTROL ASSEMBLY TO CONTROL MOVEMENT OF THE PISTON INCLUDING A NUMBER OF INDIVIDUALLY EXTENSIBLY AND RETRACTIVELY MOVABLE RAMS; A PORTED HYDRAULIC MANIFOLD FOR THE NUMBER OF RAMS AND PROVIDED WITH A LIKE NUMBER OF SIDE PORTS SLIDABLY RECEIVING THE RAMS, SAID MANIFOLD HAVING A MAIN CENTRAL CHAMBER WHICH IS COMMON TO THE RAMS, AND WHICH IS GENERALLY CYLINDRICALLY ELONGATED IN THE DIRECTION OF THE LONGITUDINAL AXIS OF THE MANIFOLD; SAID RAMS EACH PROJECTING INWARDLY THROUGH THE PLANE OF THE RECEIVING PORT TO A POINT OF ADJACENCY TO ONE ANOTHER WITHIN, AND FREE FROM CONTACT WITH THE INTERIOR OF, THEIR COMMON CHAMBER IN THE HYDRAULIC MANIFOLD; MEANS FOR ACTIVATING SELECTED ONES OF SAID RAMS TO CAUSE DISPLACEMENT OF LIQUID IN SAID COMMON HYDRAULIC MANIFOLD WHICH COMBINES THE OUTPUT DISPLACED BY THE ACTIVATED RAMS; AND MEANS IN THE OUTPUT OF SAID MANIFOLD PROVIDING AT TIMES A ONE WAY HYDRAULIC DRIVE COLUMN FLOWING FROM SAID RAMS AND COMMUNICATIVELY CONNECTED WITH AN INPUT TO THE DRIVEN PISTON PROVIDING INPUT LIQUID FLOW TO ONE SIDE THEREOF; AND INTERCONNECTING MEANS INCLUDING A RESERVOIR AND PROVIDING AT OTHER TIMES A ONE WAY RETURN FLOW FROM THE PISTON TO THE RAMS, VIA THE RESERVOIR.