| 摘要 |
<p>A control system for a web-feeding machine used to provide a continuous supply of material having successive labels and registration marks printed serially thereon is disclosed. The machine has an assembly for splicing the material from a ready web and the material severed from a running web wherein the response of the assembly after being actuated is delayed by a response time T. The control system comprises a driving circuit having an input and an output electro-mechanically coupled to the splicing assembly actuated thereby in response to a signal applied to the input thereof, a scanner positioned adjacent the material to provide a signal in response to the presence of a registration mark, and an encoder for providing a fixed number of pulses proportional to a corresponding length of the moving material. The control system also comprises a control circuit connected to the scanner, the encoder and the input of the driving circuit. The control circuit counts the number of encoder pulses between successive scanner signals and then decrements from that number to zero and, responsive to a scanner signal, provides a time delay To preset to approximate the response time T and decrements to zero from a preset number D after the time delay To has expired. The control circuit also provides a splice signal SS and supplies a splice-command signal SC to the input of the driving circuit in response to the splice signal SS. The machine accomplishes a splice-in-register after the splice-command signal SC has been applied thereto.</p> |
