1 within the ring r 2 along the discharge channel 52 it must be noted that the eleventh individual sheet b 11 is still in the unprinted condition preceding the input section 28 and the individual sheet b 6 as well as the following individual sheets b 7 b 8 b 9 have not yet past through the connecting channel 48 fig2 shows an operating phase wherein the first individual sheet b 1 at the shunt w 2 is threaded in between the individual sheets b 6 and b 7 and is conveyed upward in the connecting channel 48 as mentioned the individual sheets b 1 through b 11 are conveyed with a speed higher than the transfer printing speed after leaving the printing unit d 1 being conveyed to the printing unit d 2 as a result thereof the distance between the individual sheets increases this distance is utilized in the invention for threading the individual sheets in that derive from the printing unit d 2 and are arranged at the start of the group fig2 shows the operating condition wherein the individual sheet b 1 is conveyed in the direction of the first printing unit d 1 after leaving the turnover w 3 the individual sheet b 6 by contrast has been conveyed in.