Image forming apparatus for correcting sheet conveyance misalignment

Abstract

An image forming apparatus includes a transfer section that transfers an image onto a sheet, a sheet conveying member that is provided upstream of the transfer section in a sheet conveyance direction and conveys the sheet, and a hardware processor that controls displacement of the sheet conveying member in such a way that the sheet is displaced along the width direction of the sheet. The hardware processor performs first displacement control in which the sheet conveying member is displaced in a direction which is specified in advance with respect to the sheet and in which an edge of the sheet in the width direction is directed toward a target position and second displacement control in which the sheet conveying member is displaced in the direction opposite the direction of the first displacement.

What is claimed is: 
     
         1 . An image forming apparatus comprising:
 a transfer section that transfers an image onto a sheet;   a sheet conveying member that is provided upstream of the transfer section in a sheet conveyance direction and conveys the sheet; and   a hardware processor that controls displacement of the sheet conveying member in such a way that the sheet is displaced along a width direction of the sheet,   wherein the hardware processor   sets a point of time of start of the displacement in such a way that the sheet conveying member is allowed to be displaced toward both sides of the width direction, and   displaces the sheet conveying member based on a result of sensing performed by a deviation sensing unit that senses a direction in which an edge of the sheet in the width direction deviates from a target position in such a way that the sheet conveying member is not moved in a direction in which the edge of the sheet moves away from the target position.   
     
     
         2 . The image forming apparatus according to  claim 1 ,
 wherein the hardware processor starts displacing the sheet conveying member, then causes a detecting unit that detects the edge of the sheet in the width direction to detect the edge of the sheet, and stops the displacement based on a result of the detection when the edge of the sheet reaches the target position.   
     
     
         3 . The image forming apparatus according to  claim 1 ,
 wherein the hardware processor displaces the sheet conveying member based on a result of the sensing of the deviation direction after a front end of the sheet enters the transfer section.   
     
     
         4 . An image forming apparatus comprising:
 a transfer section that transfers an image onto a sheet;   a sheet conveying member that is provided upstream of the transfer section in a sheet conveyance direction and conveys the sheet; and   a hardware processor that controls displacement of the sheet conveying member in such a way that the sheet is displaced along a width direction of the sheet,   wherein the hardware processor starts displacing the sheet conveying member in a first direction, then causes a detecting unit that detects an edge of the sheet in the width direction, and stops the displacement in the first direction based on a result of the detection performed by the detecting unit in such a way that the edge of the sheet reaches a target position, and   conveys the sheet in such a way that the edge of the sheet in a position of the detecting unit deviates in the direction opposite the first direction with respect to the target position.   
     
     
         5 . The image forming apparatus according to  claim 4 ,
 further comprising an offset unit that offsets, in a second direction opposite the first direction, a portion of the sheet in the position of the detecting unit.   
     
     
         6 . The image forming apparatus according to  claim 5 ,
 wherein the offset unit conveys the sheet in such a way that the edge of the sheet in the position of the detecting unit deviates in the second direction with respect to the target position.   
     
     
         7 . The image forming apparatus according to  claim 6 ,
 wherein the offset unit includes a roller having a shaft that deviates from the sheet conveyance direction.   
     
     
         8 . The image forming apparatus according to  claim 6 ,
 wherein the offset unit includes rollers having diameters that differ from each other in the width direction.   
     
     
         9 . An image forming apparatus comprising:
 an image writing unit that writes an image;   a displacing unit capable of displacing a conveyed sheet; and   a hardware processor that shifts a position where the image writing unit writes the image in such a way that the displacing unit is always displaced in a same direction.   
     
     
         10 . The image forming apparatus according to  claim 9 ,
 wherein the hardware processor shifts the image writing position and a displacement aim position aimed by the displacing unit in such a way that the displacing unit is always displaced in the same direction.   
     
     
         11 . The image forming apparatus according to  claim 10 ,
 wherein the hardware processor shifts the displacement aim position and the image writing position in such a way that the displacing unit is always displaced in the same direction in a case where the displacing unit is displaced multiple times on a same sheet.   
     
     
         12 . The image forming apparatus according to  claim 11 ,
 wherein the hardware processor shifts the displacement aim position to a position where the displacement aim position does not intersect a side edge of the sheet from a front end thereof to a rear end thereof in the direction in which the sheet is conveyed.