Short paper path electronic deskew system
AssigneeXerox Corporation
InventorGeorge J. Roller
Life of this patent
Estimating the term…
Abstract
An apparatus and method to deskew sheets in a short paper path in an electrophotographic printing machine by differentially driving two sets of rolls so as to create a paper buckle buffer zone in the sheet and then differentially driving a roll set to correct the skew while the sheet is still within the nips of multiple drive roll sets. Contrary to stalled roll techniques, leading edge damage to sheets is eliminated as the deskewing rolls are initially traveling at the same velocity as the sheet.
Claims10
An apparatus for deskewing and side registering a sheet comprising:
- a plurality of drive roller sets for advancing the sheet along a primary sheet feeding path with successive ones of said plurality of drive roller sets being positioned at discrete locations along the primary sheet feeding path, and each of said plurality of drive roller sets defining a nip through which the sheet advances;
- means, operatively associated with said plurality of drive roller sets, for measuring the deviation of the sheet from the primary sheet feeding path with portions of the sheet being positioned substantially simultaneously within the nip defined by sucessive ones of said plurality of drive roller sets;
- and
- means, responsive to said measuring means, for controlling said drive roller sets to restore the sheet to the primary sheet feeding path.
An electrophotographic printing machine of the type in which a sheet is deskewed and side registered, wherein the improvement comprises:
- a plurality of drive roller sets for advancing the sheet along a primary sheet feeding path with successive ones of said plurality of drive roller sets being positioned at discrete locations along the primary sheet feeding path, and each of said plurality of drive roller sets defining a nip through which the sheet advances;
- means, operatively associated with said plurality of drive roller sets, for measuring the deviation of the sheet from the primary sheet feeding path with portions of the sheet being positioned substantially simultaneously within the nip defined by successive ones of said plurality of drive roller sets;
- and
- means, responsive to said measuring means, for controlling said drive roller sets to restore the sheet to the primary sheet feeding path.
Dependencies are inferred from the claim text.