Ultrasonic welding system for joining electrical conductors together has converter and sonotrode and has control circuit comparing actual curve of pressure plotted against time with ideal curve

摘要

The ideal curve (10) rises at a gradually decreasing rate to a sharp cutoff at a given time (t e). Different measured curves (16,18) of pressure or loading (P) plotted against time (t) may be obtained. If the curve initially drops below the ideal curve then rises above it, the welding time may be increased giving a later cutoff point (t e3). If the curve initially rises above the ideal curve the welding time is cut short (t e1). Various different frequencies of ultrasound, e.g. 20, 35 or 40 kHz may be used.