Skewed sheet correcting device and image forming apparatus

Abstract

A skewed sheet correcting device includes: first and second shutter members which move to a first position in which the first and second shutter members are pushed to be movable by a leading edge of a sheet, a second position which is disposed further downstream of the sheet conveyance direction than the first position to latch the leading edge of the sheet, and a third position which allows the sheet to pass; and a movement regulating member which, when one of the shutter members does not move to the second position, regulates the other shutter member in the second position, and, when both the first and second shutter members move to the second position, allows the first and second shutter members to move to the third position.

What is claimed is: 
     
         1 . A skewed sheet correcting device, comprising:
 a conveying portion which conveys a sheet;   first and second shutter members which are arranged along a width direction perpendicular to the sheet conveyance direction and disposed downstream of the conveying portion in the sheet conveyance direction, wherein the first and second shutter members move to a first position in which the shutter members are pushed to be movable by a leading edge of the sheet which is conveyed by the conveying portion, a second position which is disposed further downstream than the first position in the sheet conveyance direction to latch the leading edge of the sheet, and a third position which allows the sheet to pass; and   a movement regulating portion which, when the first shutter member does not move to the second position, regulates the second shutter member that has moved in the second position in the second position, when the second shutter member does not move to the second position, regulates the first shutter member which has moved in the second position in the second position, and, when both the first shutter member and the second shutter member move to the second position, allows the first and second shutter members to move to the third position.   
     
     
         2 . The skewed sheet correcting device according to  claim 1 , wherein
 the movement regulating portion includes:   a first lever member which rotates in connection with the first shutter member;   a second lever member which rotates around a common rotational shaft to the first lever member in connection with the second shutter member; and   a stopper member which, when the first shutter member does not move to the second position, regulates the movement of the second shutter member that has moved in the second position to the third position by abutting on the first lever member, and, when the second shutter member does not move to the second position, regulates the movement of the first shutter member that has moved in the second position to the third position by abutting on the second lever member, and   both the first shutter member and the second shutter member rotate to the second position to release an abutting state of the first and second lever members on the stopper member so that the first and second shutter members move to the third position.   
     
     
         3 . The skewed sheet correcting device according to  claim 1 , wherein
 the movement regulating portion includes:   a rotating member which is pushed by the first and second shutter members to rotate together with the first and second shutter members;   a first slide member which is disposed in the rotating member so as to correspond to the first shutter member and moves in an axial direction with respect to the rotating member in accordance with the movement of the first shutter member;   a second slide member which is disposed in the rotating member so as to correspond to the second shutter member and moves in an axial direction with respect to the rotating member in accordance with the movement of the second shutter member; and   a stopper member which, when the first shutter member does not move to the second position, regulates the movement of the second shutter member that has moved in the second position to the third position by abutting on the first slide member, and, when the second shutter member does not move to the first position, regulates the movement of the first shutter member that has moved the first position to the third position by abutting on the second slide member, and   the first slide member and the second slide member move as both the first shutter member and the second shutter member move to the second position to release an abutting state of the first and second slide members on the stopper member so that the first and second shutter members move to the third position.   
     
     
         4 . The skewed sheet correcting device according to  claim 1 , further comprising a pair of rollers which is disposed downstream of the conveying portion in the sheet conveyance direction,
 wherein the sheet is nipped by the pair of rollers while the first and second shutter is moved by being pushed by the sheet.   
     
     
         5 . The skewed sheet correcting device according to  claim 1 , further comprising a urging portion which applies a force to the first and second shutter members at the first position. 
     
     
         6 . An image forming apparatus, comprising:
 an image forming portion which forms an image on a sheet; and   a sheet conveying apparatus which conveys the sheet to the image forming portion,   wherein the sheet conveying apparatus includes:   a conveying portion which conveys the sheet;   first and second shutter members which are arranged along a width direction perpendicular to a sheet conveyance direction and disposed downstream of the conveying portion in the sheet conveyance direction, wherein the first and second shutter members move to a first position in which the first and second shutter members are pushed to be movable by a leading edge of the sheet which is conveyed by the conveying portion, a second position which is disposed further downstream than the first position in the sheet conveyance direction to latch the leading edge of the sheet, and a third position which allows the sheet to pass; and   a movement regulating portion which, when the first shutter member does not move to the second position, regulates the second shutter member that has moved in the second position in the second position, when the second shutter member does not move to the second position, regulates the first shutter member that has moved in the second position in the second position, and, when both the first shutter member and the second shutter member move to the second position, allows the first and second shutter members to move in the third position.   
     
     
         7 . The image forming apparatus according to  claim 6 , wherein the movement regulating portion includes:
 a first lever member which rotates in connection with the first shutter member;   a second lever member which rotates around a common rotational shaft to the first lever member in connection with the second shutter member; and   a stopper member which, when the first shutter member does not move to the second position, regulates the movement of the second shutter member that has moved in the second position to the third position by abutting on the first lever member, and, when the second shutter member does not move to the second position, regulates the movement of the first shutter member that has moved in the second position to the third position by abutting on the second lever member, and   both the first shutter member and the second shutter member rotate to the second position to release an abutting state of the first and second lever members on the stopper member so that the first and second shutter member move to the third position.   
     
     
         8 . The image forming apparatus according to  claim 6 , wherein
 the movement regulating portion includes:   a rotating member which is pushed by the first and second shutter members to rotate together with the first and second shutter members;   a first slide member which is disposed in the rotating member so as to correspond to the first shutter member and moves in an axial direction with respect to the rotating member in accordance with the movement of the first shutter member;   a second slide member which is disposed in the rotating member so as to correspond to the second shutter member and moves in an axial direction with respect to the rotating member in accordance with the movement of the second shutter member; and   a stopper member which, when the first shutter member does not move to the second position, regulates the movement of the second shutter member that has moved in the second position to the third position by abutting on the first slide member, and, when the second shutter member does not move to the first position, regulates the movement of the first shutter member that has moved to the first position to the third position by abutting on the second slide member, and   the first slide member and the second slide member move as both the first shutter member and the second shutter member move to the second position to release the abutting state of the first and second slide members against the stopper member so that the first and second shutter member move to the third position.   
     
     
         9 . The image forming apparatus according to  claim 6 , further comprising a pair of rollers which is disposed downstream of the conveying portion in the sheet conveyance direction,
 wherein the sheet is nipped by the pair of rollers while the first and second shutter is moved by being pushed by the sheet.   
     
     
         10 . The image forming apparatus according to  claim 6 , further comprising
 a urging portion which applies a force to the first and second shutter members at the first position.   
     
     
         11 . A skewed sheet correcting device, comprising:
 a conveying portion which conveys a sheet;   first and second shutter members which are arranged along a width direction perpendicular to the sheet conveyance direction and disposed downstream of the conveying portion in the sheet conveyance direction, wherein the first and second shutter members move to a first position in which the shutter members are pushed to be movable by a leading edge of the sheet which is conveyed by the first conveying portion, a second position which is disposed further downstream than the first position in the sheet conveyance direction to latch the leading edge of the sheet, and a third position which allows the sheet to pass;   a first interlocking member which interlocks with the first shutter member;   a second interlocking member which interlocks with the second shutter member;   a stopper member which, when the first shutter member does not move to the second position, regulates the movement of the second shutter member that has moved to the second position to the third position by abutting on the first interlocking member, and, when the second shutter member does not move to the second position, regulates the movement of the first shutter member that has moved to the second position to the third position by abutting on the second interlocking member, and   the abutting state of the first and second interlocking members against the stopper member is released if both the first shutter member and the second shutter member rotate to the second position, thereby the first and second shutter member can move to the third position.   
     
     
         12 . The skewed sheet correcting device according to  claim 11 , further comprising a pair of rollers which is disposed downstream of the conveying portion in the sheet conveyance direction,
 wherein the sheet is nipped by the pair of rollers while the first and second shutter is moved by being pushed by the sheet.