International Business Machines Corporation

Michael K Bullock

Edmund Hulin James, Iii

Frederick C Miller

Dennis R Hedrick

Sherwood Anderson Clay

Gregory Bingham Overton

Richard H Marvin

An illumination system for illuminating a line on a document which illumination, when reflected and focused via a lens on a sensor (or image plane), has substantially uniform light intensity along the length of the line. The illumination system includes means for compensation for lens cosine to the fourth power fall-off and an illumination cosine fall-off phenomenon, which has classically been treated as proportional to cosine to the fourth power but in the example of lamps made of coiled tungsten filaments located along the axis of the foci, is more nearly cosine to the 2.8th power. The compensation apparatus includes a cylindrical ellipse for focusing light from two lamps located on an axis which is one foci of the ellipse and the line on the document is located at the other foci of the ellipse. Reflected light from the line on the document is then reflected and focus via a lens onto a sensor. At the sensor, the image is captured for analysis or other uses, e.g., using conventional techniques for character recognition or image processing. The uniform intensity at the sensor can be facilitated by the use of appropriate dimensional relationships between components of the imaging system.

Line illumination system

A printer includes a print mechanism for performing printing operations and a print medium feeding mechanism for feeding a print medium past the print mechanism so that printing operations can be performed on the print medium. The print medium feeding mechanism includes a forward feed apparatus located downstream of the print mechanism for feeding the print medium in the forward direction past the print mechanism and a print medium tensioning apparatus. The tensioning apparatus includes at least one pair of pressure wheels rotatably mounted on the frame and located on opposite sides of a print medium being fed by the forward feed apparatus and means for restricting the rotation of at least one of the pressure wheels, whereby the pressure wheels exert a retarding force on the print medium tending to tension the print medium. Each pressure wheel is constructed so that it is flexible in the axial direction so as to permit lateral movement of a print medium as it passes between the pair of pressure wheels. The print medium feeding mechanism also includes drive means for rotating at least one of the pressure wheels in the reverse direction so as to provide for reverse feed of the print medium. This drive means is coupled through a one way coupling so as not to affect the ability of the pressure wheel to rotate during forward feed of the print medium.

Web feeding mechanism

Method and apparatus for aligning pliable material

The method and apparatus for offsetting sheets laterally with respect to their travel in a predetermined direction along a path. The method includes directing the sheets away from the path and through a second curved path aligned in skewed relation to their direction of travel in the original path and then directing the sheets back into the original path. Where some sheets are selectively fed through the second path and others only along the original path, they all can then be collected in a single stack in laterally offset relation to each other. The apparatus for offsetting the sheets includes feeding means for feeding the sheets in the predetermined direction along the original path and guide structure for directing the sheets along the curved path. The guide structure is curved about an axis skewed relative to the direction of travel of the sheets along their original path to effect the offsetting.

Job separation by a skewed trough in the paper path

A dual exit tray xerographic machine, having a hot roll fuser, supplies its output copy sheets to a large-capacity exit pocket whereat the sheets are stacked in a vertically extending pile, on a servo-movable elevator platform. The platform height is servo controlled so as to maintain the stack's top sheet at a fixed position relative to a fixed-position, generally horizontally extending, sheet discharge path. Sheet stacking is enhanced by a pair of movable bars. A hold-down bar, in its quiescent position, presses the stack's trailing edge portion down to insure reliable insertion of the next sheet. A pusher bar is maintained in an elevated quiescent position during such insertion. After the sheet has been inserted, the pusher bar lowers onto the stack, at a position between the hold-down bar and the stack's leading edge. The pusher bar thus holds the just-inserted sheet down. The hold-down bar synchronously moves in a generally elliptical path, to first clear the trailing edge of the just-inserted sheet. The hold-down bar then moves in an upward path until it again overlies the stack's trailing edge. The hold-down bar now descends onto the stack, as the pusher bar returns to its quiescent position.

Growing community of inventors

Matthews, NC, United States of America

Michael K Bullock