PAPER FEEDING DEVICE,ELECTROPHOTOGRAPHIC PRESS AND DOUBLE-SIDED PRINTING METHOD

PROBLEM TO BE SOLVED: To reduce the pitch of a printing machine and efficiently conduct double-face printing in the collation job of a plurality of pages by conveying the second paper to a timing mechanism, changing the speed of the first paper, and feeding it in a process passage at the correct timing. SOLUTION: When the second paper approaches a re-timing nip, the re-timing nip is started by a clutch mechanism via the control of a machine control device 29, the first paper is returned to a process path at the front of a transfer section, and the double-face image is transferred on the second face of the paper. The second paper is stopped by the re-timing nip during the proper period for double-face printing. A slip conveying means in a double-face passage 100 allows a one-face copy paper to be delivered from the process passage, accelerated, and stopped to match timing while the second succeeding paper follows the same route for double-face copying, and double-face copying is implemented at the maximum productivity.