Motor acceleration control for a tensioning system

Claim 1

IN COMBINATION WITH A DYNAMOELECTRIC MACHINE ADAPTED TO DRIVE A LOAD, MEANS FOR SUPPLYING CONTROLLED ELECTRIC ENERGY TO SAID MACHINE, REGULATING MEANS FOR REGULATING THE SPEED OF SAID DYNAMOELECTRIC MACHINE BY CONTROLLING THE POWER SUPPLY MEANS N RESPONSE TO A SPEED REFERENCE INPUT SIGNAL, MEANS FOR SELECTING A SIGNAL INDICATIVE IN MAGNITUDE OF A DESIRED SPEED OF SAID MACHINE, AND MEANS RESPONSIVE TO CHANGE IN MAGNITUDE OF SAID SELECTED SIGNAL FOR PROVIDING AN ACCELERATION CONTROL SIGNAL TO SAID REGULATING MEANS TO SUPPLY ACCELERATING ENERGY TO SAID MACHINE COMPRISING CIRCUIT MEANS FOR INTEGRATING A CONSTANT REFERENCE SIGNAL TO PROVIDE A FIRST SIGNAL VARYING AT A LINEAR RATE WITH RESPECT TO TIME, MEANS FOR OBTAINING THE NEGATIVE INTEGRAL OF SAID CONSTNT REFERENCE SIGNAL AFTER A TIME INTERVAL PREDETERMINED BY THE MAGNITUDE OF CHANGE OF SAID SELECTED SIGNAL TO PROVIDE A SECOND SIGNAL VARYING AT AN EQUAL BUT OPPOSITE LINEAR RATE WITH RESPECT TO SAID FIRS SIGNAL AND TO EQUAL TIME DURATION OF SAID FIRST SIGNAL TO THEREBY PROVIDE AN ACCELERATION REFERENCE SIGNAL HAVING EQUAL BUT OPPOSITE LEADING AND TRAILING EDGES, MEANS FOR INTEGRATING SAID ACCELERATION REFERENCE SIGNAL TO PROVIDE AN ACCELERATION CONTROL SIGNAL INITIATING AND TERMINATING AT SUBSTANTIALLY CONSTANT CHANGE OF RATE OF CHANGE, THE TIMEOF INTEGRATION OF SAID ACCELERATION REFERENCE SIGNAL BEING SUBSTANTIALLY LONGER THAN ANY TIME CONSTANTS OF SAID REGULATING MEANS, AND MEANS FOR APPLYING SAID ACCELERATION CONTROL SIGNAL TO SAID REGULATING MEANS TO CAUSE ACCELERATING ENERGY TO BE APPLIED TO AND REMOVED FROM SAID MACHINE AT A SUBSTANTIALLY CONSTANT RATE OF CHANGE TO SMOOTHLY CHANGE THE SPEED OF SAID MACHINE TO THE VALUE SELECTED BY SAID SPEED SELECTING MEANS.