Patent ID: 7450874
Filing Date: 2008-11-11
Classification: B65H,G03G

Abstract:
1. An image forming apparatus comprising an original reading portion disposed in an upper portion of the apparatus main body, a feed portion disposed in a lower portion of the apparatus main body, and a printing portion disposed between the original reading portion and the feed portion, wherein a paper post-processing portion that performs a plurality of types of paper post-processing for recording paper transported from the apparatus main body after printing by the printing portion is finished, and a discharge portion to which recording paper is discharged after paper post-processing by the paper post-processing portion is finished, are disposed in a space of the apparatus main body formed by the original reading portion, the printing portion, and the feed portion, a control portion is provided that controls the paper post-processing portion according to print conditions selected when a print request is made, wherein in the paper post-processing portion, a punching unit provided with a hole-punching function is provided on the upstream side in the paper transport direction towards the printing portion, a stapling unit provided with a stapling function is provided on the downstream side, discharge rollers that discharge recording paper to the discharge portion are provided in the stapling unit, and the discharge rollers are provided with a shifter function, and the control portion performs control of the paper post-processing portion according to a print condition of whether to perform duplex print processing or to perform simplex print processing, a print condition of whether or not to perform shifter processing with the discharge rollers, a print condition of whether or not to perform hole-punch processing with the punching unit, and a print condition of whether or not to perform staple processing with the stapling unit, wherein in the stapling unit, in addition to the paper transport path that connects from the punching unit, a switchback path is formed that is used when performing duplex print processing, and a branching gate is provided at the branching position of the recording paper transport path and the switchback transport path, and the control portion, when staple processing is included in the selected print conditions, swings the branching gate several times when the trailing edge of the recording paper has separated from the discharge rollers that discharge the recording paper from the paper transport path to the stapling stage where staple processing is performed.