PAPER THICKNESS DETECTION
Original Publication Date: 1990-Feb-28
Included in the Prior Art Database: 2004-Apr-05
Xerox Disclosure Journal
A device for corrugating light weight sheets to enhance beam strength and for determining their thickness is shown in Figures 1 and 2. A sheet of paper 10 travels along a paper transport path (into the page). Idler rollers (not shown) provide a drive nip to force paper 10 into the constricted area. The paper is corrugated by a plurality of wire springs 12 interacting with a plurality of rollers 14 of different diameters mounted on drive shaft 16 with the springs pushing the paper into the areas over the smaller-diameter roller 16. The spring 12 can have its reacting energy stored by mechanical strain, permanent magnet, etc.. The opposing roller-drive combination minimizes diving of light weight sheets. Upward displacement of tip 18 of spring 12 depends on individual sheet stiffness (thicker sheets generate more upward tip motion than thinner, more compliant sheets). The thickness of a compiled set can be calculated by tracking the number of fed sheets in conjunction with the thickness of an individual sheets, which is extrapolated by a transducer dynamically measuring the displacement of tip 18. this transducer can be mechanical, radiometric, pneumatic, etc..