Browse Prior Art Database

Preventing the Jamming of the Paper in a Printer Due to Buckling

IP.com Disclosure Number: IPCOM000039623D
Original Publication Date: 1987-Jul-01
Included in the Prior Art Database: 2005-Feb-01
Document File: 3 page(s) / 42K

Publishing Venue

IBM

Related People

McElroy, RM: AUTHOR [+3]

Abstract

Paper, for example, in a continuous web, is advanced in the forward direction and in the reverse direction along a path through a printer formed with constrictions. When being advanced in the forward direction, the paper is pulled along the path by tractors formed with pins which engage in holes in the edges of the paper. When being advanced in the reverse direction, the paper is pulled by rubber rollers which pinch against an opposing set of idler rollers. The tractors must also reverse direction, and because tractors always feed positively, the pinch rollers must overdrive slightly, slipping against the paper so that the paper column is always in tension and never pushed by the tractors.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 52% of the total text.

Page 1 of 3

Preventing the Jamming of the Paper in a Printer Due to Buckling

Paper, for example, in a continuous web, is advanced in the forward direction and in the reverse direction along a path through a printer formed with constrictions. When being advanced in the forward direction, the paper is pulled along the path by tractors formed with pins which engage in holes in the edges of the paper. When being advanced in the reverse direction, the paper is pulled by rubber rollers which pinch against an opposing set of idler rollers. The tractors must also reverse direction, and because tractors always feed positively, the pinch rollers must overdrive slightly, slipping against the paper so that the paper column is always in tension and never pushed by the tractors. Due to the constrictions in the paper path, the thicker portions of the paper web (primarily the in-folds and out-folds of a box of fan-folded paper) may tend to jam in the reverse direction, causing the rollers to slip excessively and the positive feed provided by the tractors to tend to buckle the paper. The buckle may be advanced into the constrictions in the path of the paper resulting in further jams and the failure of the paper feed mechanism. In order to avoid this jamming, the printer is provided with a bar which falls by its own weight onto the paper between the constrictions in the feed path and the tractors so as to flatten the paper and prevent any buckles in the paper from entering the constrictions and further jamming the feed mechanism. As illustrated in the figure, which is a diagrammatic side view of a printer, the printer includes a platen 1 over which the paper 2 is advanced by means of tractors 3 located above the platen and rollers 4 located below the platen. The tractors 3 are formed with pins 5 which engage in holes in the edge of the paper 2 in the conventional manner. Opposite the platen 1 the printer is formed with a printing mechanism 6, including hammers which press the paper 2 against the platen 1 in each printing operation. Between the printing mechanism 6 and the platen 1 are located an ink ribbon 7 and a shield 8 attached to a paper shield frame 9, which prevents the ribbon 7 from making contact with the paper 2 exc...