Rolling mill motor speed control apparatus

Claim 1

IN SPEED CONTROL APPARATUS FOR A PLURALITY OF DRIVE MOTORS RESPECTIVELY OPERATIVE WITH THE MULTIPLE STANDS OF A WORKPIECE STRIP ROLLING MILL INCLUDING A STRIP COILING DEVICE, THE COMBINATION OF FIRST VOLTAGE SUPPLY MEANS OPERATIVE WITH SAID MOTORS TO PROVIDE A FIRST PREDETERMINED SPEED OF OPERATION, SECOND VOLTAGE SUPPLY MEANS OPERATIVE WITH SAID MOTORS TO PROVIDE A SECOND PREDETERMINED SPEED OF OPERATION GREATER THAN SAID FIRST SPEED, FIRST LOAD SENSING MEANS OPERATIVE WITH SAID STRIP COILING DEVICE FOR PROVIDING A FIRST OUTPUT CONTROL SIGNAL WHEN THE LEADING-END OF THE WORKPIECE STRIP IS BEING COILED BY SAID STRIP COILING DEVICE, SECOND LOAD SENSING MEANS OPERATIVE WITH EACH OF SAID STANDS TO SENSE THE PASSAGE OF THE TAIL END OF THE WORKPIECE STRIP THROUGH EACH OF SAID STANDS, FIRST CIRCUIT MEANS CONNECTED BETWEEN THE FIRST VOLTAGE SUPPLY MEANS AND SAID DRIVE MOTORS FOR INITIALLY ENERGIZING ALL OF SAID MOTORS TO OPERATE AT SAID FIRST SPEED, SECOND CIRCUIT MEANS CONNECTED BETWEEN THE SECOND VOLTAGE SUPPLYMEANS AND ALL OF SAID DRIVE MOTORS AND BEING RESPONSIVE TO SAID FIRST OUTPUT CONTROL SIGNAL FOR ENERGIZING SAID MOTORS TO OPERATE AT SAID SECOND SPEED WHEN A WORKPIECE STRIP IS BEING COILED BY SAID STRIP COILING DEVICE, AND THIRD CIRCUIT MEANS OPERATIVE WITH THE SECOND VOLTAGE SUPPLY MEANS AND OPERATIVE WITH THE SECOND VOLTAGE SUPPLY MEANS FOR SEQUENTIALLY RETURNING EACH OF SAID MOTORS TO OPERATION AT SAID FIRST SPEED AS THE TAIL-END OF THE WORKPIECE STRIP RESPECTIVELY LEAVES EACH OF SAID STANDS IN PASSING THROUGH SAID WORKPIECE STRIP ROLLING MILL.