PURPOSE: To achieve quick work, when using the picture image recorder in a copier in double speed mode, by arranging means for accelerating the sheet material at predetermined position in feeding system thereby accurately overlapping the sheet materials passed through indivigual picture image forming section.

CONSTITUTION: The transfer paper to be fed sequentially from copy paper storage sections F1, F2 will pass through independent paths aWf, hWl respectively to receive picture images at each picture image forming section 1, 2 including photosensitive drums D1, D2 and discharged to each stacker S1, S2. Here, a pair of rollers R1, R2 for accelerating the transfer paper are provided at the upstream of the confluence P of both paths f, l in the transfer paper discharge control section 3. Then a sheet of copy P1 in one copy group is accelerated to enlarge the interval against the following copy P3 to V1, and when said interval V1 exceeds over the length L of next copy P2 in the other copy group, the copy P2 is accelerated and inserted into the interval V1.