Apparatus for the adjustment of the tension in a rotating gripping device of a machine tool

摘要

An apparatus for the adjustment of the tension in rotating gripping devices, which are operable with variable power outputs and follow (hysteresis) distinct tension-characteristics for build-up and withdrawal. In order to make possible a stabilization of the tension which is independent from the rotational speed, a desired value for the tension and an internal tolerance allotment for an upper and a lower desired adjustment value are presupposed in a control apparatus. In the control apparatus a leading regulated quantity is produced digitally for the changing of power outputs. The leading regulated quantity is reduced when the desired value approaches a presupposed amount, so that the actual value in presupposed intervals lessens regularly through the regulated quantity reduction under the desired value and is again increased. By an increase of the actual value to one of the upper tolerance allotment presupposed values, the regulated quantity is lessened as a desired value to the reduction of the tension and overcoming of the hysteresis under allotments of the lower adjusted desired values, until the actual value has fallen to a value between the desired value and the presupposed desired value.