Splicer control

Abstract

The web from a running roll passes through a festoon in which an amount of web is stored. Upon the application of a splice command signal, the speed of the running roll is reduced from an initial or line speed V linearly at a rate R1. As the speed of the running roll decreases, the rate at which the festoon web length decreases reaches a preselected fraction of the speed V. This indicates that the running roll is stopped. A splice initiate signal is then generated. The web from the running roll is spliced to the web from a reserve roll. Following the splice, the speed of the web from the reserve roll is accelerated linearly at a rate R2 to speed V. If the rate of reduction of running roll speed is independent of the initial speed V, the same web tensions are experienced during braking of the running roll regardless of the initial speed V. If the rate is made dependent on the initial speed V, lower web tensions are experienced during braking for lower initial speeds V. By accurately controlling the rates of acceleration and deceleration the timing and web travel during splices are predictable, suiting the splicer to use in an automated system where splices are to be matched.