Sheet feeding apparatus, image forming apparatus, and image forming system

Abstract

A sheet feeding apparatus includes: a front edge air part that blows front edge air, along a conveying direction of a sheet stacked, to a front edge side of the sheet; side edge air parts that are provided to face each other along an orthogonal direction to the conveying direction of the sheet and blow side edge air, along the orthogonal direction, to respective side edge sides of the sheet; a suction part that suctions, by a negative pressure, the sheet to which the front edge air and the side edge air are blown; and a conveyer that suctions and conveys the sheet suctioned by the suction part, wherein the front edge air and the side edge air are blown to the sheet to float the sheet in a posture in which a portion protruding from the conveyer of the sheet is lower than a conveying surface of the conveyer.

What is claimed is: 
     
         1 . A sheet feeding apparatus comprising:
 a front edge air part that blows front edge air, along a conveying direction of a sheet stacked, to a front edge side of the sheet;   side edge air parts that are provided to face each other along an orthogonal direction to the conveying direction of the sheet and blow side edge air, along the orthogonal direction, to respective side edge sides of the sheet;   a suction part that suctions, by a negative pressure, the sheet to which the front edge air and the side edge air are blown; and   a conveyer that suctions and conveys the sheet suctioned by the suction part, wherein   the front edge air and the side edge air are blown to the sheet to float the sheet in a posture in which a portion protruding from the conveyer of the sheet is lower than a conveying surface of the conveyer.   
     
     
         2 . The sheet feeding apparatus according to  claim 1 , wherein
 two or more sets of the side edge air parts are provided along the conveying direction, and   in a case where a length of the sheet is equal to or greater than a preset threshold, until the sheet is suctioned by the conveyer, at least one of strength, a blowing position, or a blowing direction of the side edge air is set to float the sheet in a posture in which the sheet is lower in lifting of the sheet by upstream side edge air of the side edge air blown from an upstream side along the conveying direction than in lifting of the sheet by downstream side edge air of the side edge air blown from a downstream side along the conveying direction.   
     
     
         3 . The sheet feeding apparatus according to  claim 1 , wherein
 strength of upstream side edge air of the side edge air blown from an upstream side along the conveying direction is set weaker than strength of downstream side edge air of the side edge air blown from a downstream side along the conveying direction.   
     
     
         4 . The sheet feeding apparatus according to  claim 1 , wherein
 a position of a side edge air opening of upstream side edge air of the side edge air blown from an upstream side along the conveying direction is provided at a lower position in a stacking direction of the sheet than a position of a side edge air opening of downstream side edge air of the side edge air blown from a downstream side along the conveying direction.   
     
     
         5 . The sheet feeding apparatus according to  claim 1 , wherein
 a blowing direction of upstream side edge air of the side edge air blown from the upstream side along the conveying direction is set more downward in a stacking direction of the sheet than a blowing direction of downstream side edge air of the side edge air blown from a downstream side along the conveying direction.   
     
     
         6 . The sheet feeding apparatus according to  claim 1 , further comprising
 a side edge detection sensor that detects a posture of a side edge of the sheet, wherein   the side edge air part   changes an amount of blowing of the side edge air depending on a floating height of the sheet detected by the side edge detection sensor.   
     
     
         7 . The sheet feeding apparatus according to  claim 6 , further comprising
 a side edge guide member that includes the side edge air part and guides the posture of the side edge of the sheet, wherein   the side edge air part   stops blowing of the side edge air in a case where it is detected by the side edge detection sensor that the sheet has come out of the side edge guide member.   
     
     
         8 . An image forming apparatus comprising:
 a front edge air part that blows front edge air, along a conveying direction of a sheet stacked, to a front edge side of the sheet;   side edge air parts that are provided to face each other along an orthogonal direction to the conveying direction of the sheet and blow side edge air, along the orthogonal direction, to respective side edge sides of the sheet;   a suction part that suctions, by a negative pressure, the sheet to which the front edge air and the side edge air are blown; and   a conveyer that suctions and conveys the sheet suctioned by the suction part, wherein   the front edge air and the side edge air are blown to the sheet to float the sheet in a posture in which a portion protruding from the conveyer of the sheet is lower than a conveying surface of the conveyer.   
     
     
         9 . An image forming system comprising:
 a front edge air part that blows front edge air, along a conveying direction of a sheet stacked, to a front edge side of the sheet;   side edge air parts that are provided to face each other along an orthogonal direction to the conveying direction of the sheet and blow side edge air, along the orthogonal direction, to respective side edge sides of the sheet;   a suction part that suctions, by a negative pressure, the sheet to which the front edge air and the side edge air are blown; and   a conveyer that suctions and conveys the sheet suctioned by the suction part, wherein   the front edge air and the side edge air are blown to the sheet to float the sheet in a posture in which a portion protruding from the conveyer of the sheet is lower than a conveying surface of the conveyer.