US 4,011,975 A · Web handling system

Abstract

A web handling system is described for incrementally feeding a web, and preferably multiple webs, to a processing station. Each web is advanced to the processing station by a pair of web-feeding rollers. One motor drives all of the web-feeding roller pairs through respective clutch-brakes connected to each roller pair. Each web has index marks imprinted along its length at intervals corresponding to intervals at which it is desired to precisely register the web with the processing station. A first detecting means disposed along one of the web paths (or similar detecting means along another web path) initially detects an index mark on the web travelling that path to provide a signal which decelerates the motor and thus slows all of the web-feeding rollers and the webs. Second index mark detecting means, one for each web path, then detect the index marks on the respective associated webs as they now more slowly advance towards the processing station. When actuated, each second index mark detecting means produces a signal which disengages the clutch and applies the brake of the clutch-brake associated with the same web to independently stop each web. The second index mark detecting means are positioned relative to the processing station such that the desired portion of each web is registered with the processing station when the second index mark detecting means causes its associated web to independently stop. Since the web-feeding rollers are slowed prior to stopping and since each web is independently indexed with the processing station, each web is precisely registered with the processing station.

Claims12

Dependent claims

A system for handling a first web and at least one further web to register preselected portions of the webs at increments with a processing station, the system comprising:

means for advancing said first web to said processing station;
web control means for detecting the approach of a preselected web portion of said first web to the processing station;
means responsive to the means for detecting the approach for slowing the web advance of the first web;
registration means for detecting the registration of said preselected web portion with the processing station;
and means responsive to the means for detecting said registration for stopping the slowed first web;
said means for advancing said first web also comprising means for advancing said further web;
said means for detecting the approach of said web portion being operatively associated with only said first web for jointly slowing both said first and further webs but said registration detecting means and said responsive means being associated with both said first and further webs for independently stopping said webs, said registration detecting means including first and second independently operable means for detecting registration of preselected web portions of both said first and further webs, respectively, with said processing station, and said responsive means for stopping said webs including first and second independently activatible means for stopping each of said first and further webs, respectively, in response to the respective means for detecting registration, whereby exact registration of each web for processing by the processing station occurs despite relative misalignment of the first and further webs.

4 more elements

Dependencies are inferred from the claim text.

Web handling system

Life of this patent

Web handling system

Life of this patent

Abstract

Claims12