IMAGE FORMING APPARATUS CAPABLE OF DOUBLE-SIDED RECORDING

PROBLEM TO BE SOLVED: To provide a recording paper conveyance device for an image forming apparatus capable of double-sided recording that ensures a satisfactory quality image by controlling loops in a recording paper, which arise due to driving speed differences when a plurality of rollers, such as a fixing roller, a transport roller, a paper ejection roller, and an inverting roller, are driven with a common driving source. SOLUTION: The plurality of rollers, e.g., the fixing roller 15, the transport roller 19, the paper ejection roller 17, and the inverting roller 18, are fitted in a single unit and are driven by the common driving source. This eliminates the need for loop control, until the leading end of the usable maximum recording paper (the longest paper) reaches the fixing roller 15. After the start of a fixing process by a fixing device FX, loop control is exerted for the longest paper, until the trailing end of the longest paper passes along the transport roller 19. A difference ΔL1, between the counter resist roller 13 and the transport roller 19 in the amount of transport, is held as a loop. In order that the loop LP 1 be held so as to prevent troubles, such as bending of recording papers in a conveyance path, the loop LP1 is maintained at the difference ΔL1 to the amount of transport or smaller. COPYRIGHT: (C)2008,JPO&INPIT