Experimental Investigation of Mechanical Press Dynamic Behaviors by Ram Displacement Waveform Curves

Abstract

This paper analyses the measurement demands of the mechanical-press ram displacement waveform on the sample frequency and displacement resolution. A virtual instruction system was developed that contains a USB2069 data acquisition card and a software based LabVIEW, and a Hall sensor sensitizes the displacement especially at the ram bottom dead center (BDC). The paper describes and explains the characteristic behaviors of the ram displacement curve on the macro shape and the micro waveforms of BDC in various shutheights. The discussion indicates that a flat bottom region of BDC waveform is due to the clearance between the transmission devices and the elastic distortion of the press frame, and the position of the punch backward departure is a steady inflexion point, which is the best BDC bottommost position. Based the time of flat BDC region, the clearance values can be calculated.