Image forming apparatus and controlling method thereof

摘要

In a one-face mode, a first sheet discharge portion 9 arranged on an upper face of an apparatus body 1, or a second sheet discharge portion 10 arranged in the apparatus body 1 so as to be freely opened and closed is opened, and a sheet forming an image on one surface thereof is discharged to this second sheet discharge portion 10. In a both-face mode, a sheet forming images on both surfaces thereof is conveyed to the first sheet discharge portion 9 through a sheet discharge path formed by closing the second sheet discharge portion 10. When it is detected in the both-face mode that the second sheet discharge portion 10 is opened on the basis of a detecting signal from a second sheet discharge portion open and close detecting portion S4, a controller controls the rotating direction of a forward and reverse rotatable conveying device 8 on the basis of timer information from a timer device at the detecting time and the sheet forming the image, on one surface thereof is conveyed to the first sheet discharge portion 9 or the second sheet discharge portion 10, or a both-face conveying portion 2.