Sheet conveying apparatus

Abstract

In order to provide a configuration capable of correcting skew and lateral displacement of a sheet, a pair of regulation guides are capable of guiding opposite end edges in a sheet width direction of a sheet S conveyed by a conveyance belt and spheres, while being nipped. Further, the pair of regulation guides are capable of shifting to guide positions for guiding the opposite end edges of the sheet, and retract positions retracted from the opposite end edges of the sheet more than the guide positions, wherein a control section conveys the sheet by the conveyance belt in a state in which the pair of regulation guides are positioned in the retract positions, and brings a front end of the sheet in a state of being conveyed by the conveyance belt into contact with a conveyance roller pair with drive halted.

1 . A sheet conveying apparatus which receives and conveys a sheet conveyed by a conveyance member for conveying the sheet in a predetermined conveyance direction, comprising:
 an endless conveyance belt disposed on a downstream side of the conveyance member in the conveyance direction to include a conveyance face extended in the conveyance direction and to convey the sheet delivered to the conveyance face in the conveyance direction;   a plurality of spheres disposed in positions opposed to the conveyance face in the conveyance direction to be rotatable in any direction, while nipping the sheet between the spheres and the conveyance face;   a conveyance roller pair disposed on the downstream side of the conveyance belt in the conveyance direction to be able to convey the sheet;   a pair of regulation guides disposed on opposite sides of the conveyance belt with respect to a sheet width direction crossing the conveyance direction to be able to guide opposite end edges in the sheet width direction of the sheet conveyed by the conveyance belt and the spheres, while being nipped;   a guide shift section capable of shifting the pair of regulation guides to guide positions for guiding the opposite end edges of the sheet in the sheet width direction and retract positions retracted from the opposite end edges of the sheet in the sheet width direction more than the guide positions; and   a control section adapted to control the conveyance belt, the conveyance roller pair and the guide shift section,   wherein in conveying the sheet, the control section is capable of executing a mode for conveying the sheet by the conveyance belt in a state in which the pair of regulation guides are positioned in the retract positions, positioning the pair of regulation guides from the retract positions to the guide positions after bringing a front end of the sheet in a state of being conveyed by the conveyance belt into contact with the conveyance roller pair with drive halted, and subsequently, driving the conveyance roller pair to convey the sheet to the downstream side in the conveyance direction.   
     
     
         2 . The sheet conveying apparatus according to  claim 1 , wherein in executing the mode, the control section positions the pair of regulation guides from the retract positions to the guide positions, and subsequently, after driving the conveyance roller pair to start conveyance of the sheet to the downstream side in the conveyance direction by the conveyance roller pair, shifts the pair of regulation guides from the guide positions to the retract positions. 
     
     
         3 . The sheet conveying apparatus according to  claim 1 , wherein the guide positions are positions where a distance between the pair of regulation guides is longer than a length of the sheet in the sheet width direction by a predetermined length. 
     
     
         4 . The sheet conveying apparatus according to  claim 1 , wherein in conveying the sheet, when a length of the sheet in the conveyance direction is a first length, the control section executes the mode, while when the length of the sheet in the conveyance direction is a second length longer than the first length, the control section shifts the pair of regulation guides from the retract positions to the guide positions, while conveying the sheet by the conveyance belt, and delivers the sheet from the conveyance belt to the conveyance roller pair, without halting drive of the conveyance roller pair. 
     
     
         5 . The sheet conveying apparatus according to  claim 1 , wherein in conveying the sheet, when weighing of the sheet is first weighing, the control section executes the mode, while when the weighing of the sheet is second weighing larger than the first weighing, the control section shifts the pair of regulation guides from the retract positions to the guide positions, while conveying the sheet by the conveyance belt, and delivers the sheet from the conveyance belt to the conveyance roller pair, without halting drive of the conveyance roller pair.