Register control system for web operating apparatus

Abstract

A control system is disclosed for acquiring and maintaining a register condition for successive repeat lengths of a moving web relative to a cut-off apparatus or the like in a web operating apparatus of the type which includes an adjustment means for advancing or retarding the web relative to the cut-off apparatus. The system operates in manual and automatic modes and while in the manual mode, an operator manipulates the adjustment means to obtain the register condition and then switches to the automatic mode which maintains the register condition. The system includes a scanner for detecting indicia and producing a mark signal, and encoder connected to the cut-off apparatus for producing a number of pulses per revolution in either rotational direction and an indication of the direction of rotation, a counter for maintaining a count of the pulses and having a terminal count corresponding to the number of pulses generated by the encoder per revolution, means for detecting the occurrence of the mark signal relative to the terminal count of the counter and generating an error signal, drive means responsive to the error signals for driving the adjusting equipment to reacquire the register condition. After the register condition is obtained during set up in manual mode, switching to automatic mode causes the first mark signal to enable the counter which is thereafter reset whenever its terminal count is reached.