Apparatus for working on a workpiece while moving

Claim 1

IN APPARATUS FOR CUTTING OFF A PREDETERMINED LENGTH OF A WORKPIECE WHILE MOVING, THE COMBINATION COMPRISING A CARRIAGE MOVABLE IN THE SAME DIRECTION AS THE WORKPIECE, CUT-OFF MEANS ON SAID CARRIAGE AND INCLUDING A CUT-OFF ELEMENT MOVABLE FROM AN INOPERATIVE POSITION IN WHICH IT IS DISENGAGED FROM THE WORKPIECE TO AN OPERATIVE POSITION IN WHICH IT ENGAGES THE WORKPIECE, MEANS FOR ACCELERATING SAID CARRIAGE TO MOVE SAID CUT-OFF ELEMENT AT THE SAME SPEED AS THE WORKPIECE IN PREDETERMINED POSITIONAL SYNCHRONIZATION THEREWITH INCLUDING FLUID OPERATED ACTUATOR MEANS FOR MOVING SAID CARRIAGE, ELECTROHYDRAULIC SERVOVALVE MEANS HAVING A CLOSED CENTER VALVE SPOOL CONTROLLING THE FLOW OF OPERATING FLUID WITH RESPECT TO SAID ACTUATOR MEANS AND END SENSING TRANSDUCER MEANS INCLUDING A MOVABLE ELEMENT ADAPTED TO ENGAGE THE LEADING END OF THE WORKPIECE AND BE MOVED THEREBY AND ARRANGED TO GENERATE A VARIABLE ELECTRICAL CONTROL SIGNAL FOR THE SERVOVALVE HAVING A MAGNITUDE PROPORTIONAL TO DISPLACEMENT OF SAID MOVABLE ELEMENT, MEANS FOR MOVING SAID CUT-OFF ELEMENT FROM ITS SAID INOPERATIVE POSITION TO ITS SAID OPERATIVE POSITION AFTER IT HAS ATTAINED SAID SAME SPEED AND POSITIONAL SYNCHRONIZATION THEREBY TO CUT OFF A PREDETERMINED LENGTH OF THE WORKPIECE FROM THE PARENT PORTION THEREOF, AND MEANS ARRANGED THEREAFTER TO FEED AN INCREASED ELECTRICAL SIGNAL TO THE SERVOVALVE THEREBY TO ACCELERATE SAID CUT-OFF ELEMENT AWAY FROM THE LEADING END OF SAID PARENT PORTION OF THE WORKPIECE.