US 7,411,206 B2 · Method and system for detecting the position of an edge of a web

Abstract

A method and system for determining the lateral position of an edge of a web are disclosed. The system includes an array of light transmitting elements and a corresponding array of lenses and an array of light receiving elements and a corresponding array of lenses. The light transmitting elements are each paired with a light receiving element and the light transmitting elements each transmit a beam of light energy towards the corresponding receiving element. The beams of light can be occluded by a web passing between the transmitting elements and the receiving elements, thereby reducing the light received by the receiving elements. The receiving elements can generate a signal that is proportional to the amount of they receive, and a controller can be used to determine the lateral position of an edge of the web in response to the signals generated by the receivers. A compensation light beam can be employed to enable the controller to compensate for several factors that can affect measurement accuracy.

Claims36

Dependent claims

A system for use in detecting an edge of a web of material, the system comprising;

a plurality of light sources being operative to transmit light, the plurality of light sources being arranged in two substantially parallel rows that are offset from one another so as to form a staggered pattern;
a first plurality of lenses positioned such that each of the first plurality of lenses focuses light transmitted from one of the plurality of light sources;
a second plurality of lenses positioned such that each of the second plurality of lenses is capable of receiving light focused by one of the first plurality of lenses;
wherein the first plurality of lenses is spatially separated from the second plurality of lenses such that a gap is formed therebetween and such that only a portion of the web can pass through the gap;
and
a plurality of light receivers positioned such that each of the plurality of light receivers can receive light focused from one of the second plurality of lenses.

3 more elements

Dependencies are inferred from the claim text.

Method and system for detecting the position of an edge of a web

Life of this patent

Method and system for detecting the position of an edge of a web

Life of this patent

Abstract

Claims36