MACHINE FOR MAKING CONCERTINA FOLDS WITH REVERSIBLE ROLLERS AND MEANS FOR REVERSING SAME

摘要

A machine for folding strips of sheet material for example paper or cardboard or the like in a concertina-like manner. It comprises a plane member for the sliding of the strip of sheet material which is to be folded and a device suitable to prevent the returning of the strip. The device is arranged at the end of the plane member towards which the strip slides. It further comprises a pair of folding members consisting of a first roller means and a pair of second rollers parallel to and tangentially engaged with the first roller means. The second rollers are rotatably supported at the outlet of said non-returning device so as to lie above and below the strip respectively and cooperate with said first roller means so as to grip the strip alternately and form the folds. Inversion means are provided to drive the rollers alternately in opposite directions and photoelectric members are positioned to actuate the inversion means according to the position of the folded sheet material. Another photoelectric device detects the trailing end of the sheet and causes ejection of the folded sheet.