Speed control system

Claim 1

IN A MILL HAVING A FIRST ROTATABLE REEL FOR STORING STRIPS OF MATERIAL, A SECOND ROTATABLE REEL FOR RECEIVING THE STRIP FROM SAID FIRST REEL, AT LEAST A SINGLE ROTATABLE ROLLS SPACED INTERMEDIATE SAID FIRST AND SECOND REELS, TACHOMETER MEANS COUPLED TO SAID FIRST REEL FOR PROVIDING AN ELECTRICAL SIGNAL PROPORTIONAL TO THE REEL SPEED, TACHOMETER MEANS COUPLED TO SAID SINGLE ROLL FOR PROVIDING AN ELECTRICAL SIGNAL PROPORTIONAL TO THE ROLL SPEED, NULL DETECTOR MEANS CONNECTED TO BE RESPONSIVE TO EACH OF SAID SPEED SIGNALS FOR PROVIDING A CONTROL SIGNAL WHEN SAID REEL AND ROLL SPEEDS HAVE A PRESELECTED RELATIONSHIP, MEANS COUPLED TO SAID SINGLE ROLL FOR PROVIDING ELECTRICAL PULSES PROPORTIONAL TO THE ROLL SPEED, PULSE COUNTING MEANS, MEANS COUPLED TO SAID COUNTING MEANS TO CAUSE SAME TO ASSUME A PREDETERMINED COUNT DEPENDENT ON SAID PRESELECTED SPEED RELATIONSHIP, SELF-BALANCING MEANS COUPLED TO THE SPEED GENERATING MEANS OF SAID ROLL FOR PROVIDING A DIGITAL OUTPUT SIGNAL CORRESPONDING TO THE SQUARE OF THE MILL RUNNING SPEED, MEANS FOR COMPARING SAID DIGITAL SIGNAL WITH THE COUNT OF SAID COUNTING MEANS FOR PROVIDING A MILL SLOW-DOWN SIGNAL WHEN SAID SIGNALS ARE SUBSTANTIALLY THE SAME, AND MILL SPEED CONTROL MEANS CONNECTED TO BE RESPONSIVE TO THE SLOW-DOWN SIGNAL FOR REDUCING THE MILL RUNNING SPEED BY REDUCING THE SPEED OF SAID FIRST AND SECOND REELS.