Drive installation for plastics bag mfg. machine - has control assigned to high dynamic drive motor and forwarding pair of rollers for intermittent supply of plastics material web

摘要

The drive has a pair of pulling rollers (1) for moving the web of material, plastics sheeting or foil, a high-powered drive motor (2) and its control unit (3). The plastics sheeting can be accelerated from a stationary position in strictly fixed intervals of feed and, after a certain movement which can be set, can be decelerated again to a standstill. The control unit possesses an analogue calculator (5) capable of generating a trigonometrical function and supplying, for controlling the motor during the feed, a d.c. voltage signal (F) of the form, F = Fo (1+ sin/alpha), the angle being between the range 270 and 630 deg. during the feed interval. The amplification factor (Fo) can be set according to the selected length of feed by the analogue calculator. ADVANTAGE - Drive for rollers can be run quietly and without losses.