Browse Prior Art Database

Original Publication Date: 1987-Feb-28
Included in the Prior Art Database: 2004-Apr-04

Publishing Venue

Xerox Disclosure Journal


In present high speed automatic document feeders, a premium is placed on single sheet feeding. One device which meets this requirement is shown in the Figure and includes a bottom friction retard feeding device which employs a nudger roll (a) to push the bottom documents of a stack into a combination gateketard separating ski (b). This ski has a steep slope on its back edge to hold most of the stack back. On the bottom of the ski, there is a friction pad (c) which is tapered on its trailing edge in order to shingle out entering documents. The retard pad serves to hold back the top documents allowing the drive roll (d) beneath the ski, to drive the bottom document out from under the stack (e). The nudger roll (a) and the retard ski are both loaded normally in an expedient fashion to obtain the proper drive and retard forces (Fnl) and (Fn2). The nudger force does not have to be relieved during feeding which makes this device more cost effective. In order to prevent the gatejretard ski from "jumping", (when the nudger roll pushes a "slug" of documents toward the gate/retard ski) a hard stop (high rate spring) (f) is positioned just above the ski. The low cost highly efficient feeder of the Figure is also adaptable for feeding copy sheets.