JPS57142800A - Method and device for measuring stopping performance of press slide in press machine - Google Patents

Abstract

PURPOSE:To detect the static point of a press slide under movement accurately by detecting the time at the point when the extent of movement displacement of the press slide attains the min. or max. value from the time when a press stop instructing signal is transmitted by the voltage change signal indicating said displacement extent and determining the stop time or stop position of the press slide. CONSTITUTION:The output voltage of a potentiometer 1 changes by drawing a curve having one period at every one reciprocation of a press slide. This output voltage is converted to pulse signals of a constant frequency in an analog to digital conversion circuit 3, and is fed to a peak holding circuit 2. In this circuit 2, the pulse signals fed from the circuit 3 are compared successively, and when the min. or max. value is detected, it is held and an output signal is fed to a control circuit 7. On the other hands, the pulses of a constant frequency are fed from a pulse oscillation circuit 5 for the time of a circuit 4 to the circuit 7 as a time signal. Further, a press stop signal is fed to the circuit 7 and the measurement of time is started. The time since holding of the circuit 2 and transmission of the output to the circuit 7 therefrom until closing of its gate is measured and the output of this time signal is fed to a display circuit 8 by which the time is displayed.