| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an image forming apparatus that reduces the size of the apparatus by simplifying its structure. <P>SOLUTION: When a first-side printed medium on which an image is formed by an image forming section 9, turns on the detection signal of an ejection sensor 19, counting of time t1 is started using a timer. When the counted time t1 does not fall within a preset time range S or when the ejection sensor 19 remains on even when the time elapses beyond the time range S, a determination is made that a jam has occurred. When the counted time t1 falls within the time range S, counting of time t2 is started using another timer. When the counted time t2 does not fall in a preset time range T or when a paper feed sensor 6 is not turned on even when the time elapses beyond the time range T, it is determined that a jam has occurred in the middle of conveyance of the first-side printed medium in the direction of return. When the first-side printed medium passes through a conveyance path 30 within the time range T and the paper feed sensor 6 is turned on, printing on the second side of the first-side printed medium is controlled. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
