Selective controller for hydraulic actuators

Claim 1

A CONTROL MECHANISM AND A HYDRAULIC SYSTEM FOR A MACHINE INCLUDING A WORK HEAD MOVABLE TO SELECTED POSITIONS RESPONSIVE TO THE ACTUATION OF SAID CONTROL MECHANISM THROUGH SAID HYDRAULIC SYSTEM, SAID CONTROL MECHANISM COMPRISING A MOVABLE ARM REST, A PLURALITY OF PRESSURE TYPE CONTROL MEANS IN SAID HYDRAULIC SYSTEM OPERATIVELY ASSOCIATED WITH SAID ARM REST FOR DIRECTING THE MOVEMENTS OF SAID WORK HEAD, SAID CONTROL MEANS INCLUDING A REVERSIBLE ROTARY VALVE MOUNTED ADJACENT SAID ARM REST, ACTUATING MEANS IN SAID HYDRAULIC SYSTEM FOR MOVING SAID WORK HEAD IN A SUBSTANTIALLY VERTICAL DIRECTION RESPONSIVE TO VERTICAL MOVEMENTS OF SAID ARM REST, SAID ARM REST BEING PIVOTABLE ABOUT A SUBSTANTIALLY VERTICAL CONTROL SHAFT, A SECOND REVERSIBLE VALVE MOUNTED ADJACENT SAID CONTROL SHAFT, A SECOND ACTUATING MEANS IN SAID HYDRAULIC CIRCUIT FORM MOVING SAID WORK HEAD LATERALLY RESPONSIVE TO LIKE MOVEMENTS OF SAID ARM REST, A PORTION OF SAID ARM REST BEING SLIDABLE IN A LONGITUDINAL DIRECTION RELATIVE TO THE REMAINDER OF SAID ARM REST, AND A THIRD REVERSIBLE HYDRAULIC VALVE AFFIXED BELOW SAID PORTION, A RECIPROCATING PLUNGER MOUNTED ON SAID PORTION TO ACTUATE SAID THIRD VALVE, SAID HYDRAULIC SYSTEM CONNECTED TO PISTON MEANS FOR RECIPROCATING SAID WORK HEAD RESPONSIVE TO LIKE MOVEMENTS OF SAID SLIDABLE PORTION OF SAID ARM REST.