Patent ID: 9671739
Date: 2017-06-06
CPC Classifications: B65H,G03G

Claim:
1. A sheet-conveying device that conveys a sheet, the device comprising: register rollers that move in a direction which is perpendicular to a conveying direction of the sheet with the register rollers nipping the sheet, and correct a position of the sheet; a guide member that constitutes a sheet-conveying route, the guide member being provided at an upstream side of the register rollers along the conveying direction of the sheet; a plurality of rollers, each roller projecting from the guide member, contacting the sheet and rotating together with the conveyance of the sheet, the plurality of rollers being provided at plural portions of the guide member at the upstream side of the register rollers along the conveying direction of the sheet; an elevating mechanism that elevates each of the plurality of rollers between a position in which the roller projects from the guide member and into the sheet-conveying route and a position in which the roller does not project from the guide member so as to escape from the sheet-conveying route; a deviation detection sensor that detects a position of the sheet in a width direction of the sheet along the direction which is perpendicular to the conveying direction of the sheet; and a control portion that is configured to perform a sheet-position correction operation in which the register rollers move along the direction which is perpendicular to the conveying direction of the sheet based on positional information of the sheet along the width direction thereof, wherein the positional information is detected by the deviation detection sensor, and wherein the position of the sheet in the width direction thereof is corrected along the direction which is perpendicular to the conveying direction of the sheet, wherein the control portion is configured to, in this order: (i) perform control to correct skew by nipping the sheet with the register rollers, (ii) control the deviation detection sensor to detect the positional information of the sheet along the width direction thereof, (iii) based on the detected positional information of the sheet along the width direction, search from among the plurality of rollers for a roller that is positioned at a position where the roller would contact an end surface of the sheet, while the sheet is being moved along the width direction thereof during the sheet-position correction operation, calculate positional information of the searched roller that is positioned at said position, and control the elevating mechanism so that the searched roller specified based on the calculated positional information does not project from the guide member and escapes from the sheet-conveying route before the sheet-position correction operation starts, and (iv) based on the detected positional information of the sheet along the width direction, perform the sheet-position correction operation in which the register rollers move along the direction which is perpendicular to the conveying direction of the sheet.