Patent GB-901276-A (GB)
Title: Improvements in or relating to the manufacture of envelopes or the like
IPC: B31B70/00
Filed: 1960-04-11
Abstract: 901,276. Folding envelope blanks. WINKLER, R., and DœNNEBIER, K. April 11 1960 [Dec. 16, 1959], No. 12777/60. Class 94(2). Relates to machines for folding the closing flaps of envelopes and comprises apparatus for reversing the motion of a rapidly moving stream of envelopes provided with means for stopping an envelope conveyed in the stream in one direction, means for slowing the movement of the envelope before it reaches the stop means and means for accelerating the envelope in the opposite direction towards a pair of folding rollers. A slot 13 is formed between guide ledges 10 and 11, the former being secured to a transverse member 6 and the latter to the upper ends of the guide ledges 10 through spacers 12. The stop is in the form of a rail 14, in the slot 13, secured to a bearing block 21. A shaft 32, rotatable in the bearing block 21, has cams 33 which act on leaf springs 43 secured to a rail 23. An envelope 8<SP>1</SP>, folded except for its closing flap, runs over guide ledges 47 between rollers 3 and 4 and thence with its bottom-flap fold foremost into the slot 13 towards the stop rail 14. The ends of the leaf springs 43 are then moving upwards from the extreme position 43<SP>1</SP>, since the shaft 32 is driven from a pinion (not shown) in the envelope machine, and the envelope is slowed down as the springs flex back so that it strikes with reduced speed against the stop rail 14 when the springs reach their highest position 43<SP>11</SP>. The roller 4 grips the closing flap of the envelope just behind the crease line with suction holes 4<SP>1</SP> and as it is drawn between rollers 4, 5 the cams 33 allow the leaf springs 43 to flex back and accelerate the movement of the envelope. With its closing flap folded between the rollers 4, 5 the envelope is delivered in the direction F. Soft rubber strips 46 act as vibration dampers for the leaf springs and allow the envelope to come into contact with the stop rail 14 over its whole width. The machine may be adjusted according to the height and format of the envelope by moving the bearing block 21 relatively to an angle member 18, on which it is mounted, the movement being accomplished by means of knurled nuts 26, and by altering the position of the angle member 18, which is clamped to a rail 16 by screws 19, 20. The bearing block 21 engages round the rail 16 and angle member 18 and is clamped by rails 23, 25 screwed to the rail 16. The bearing block 21 is locked to the rail 16 and angle member 18 by a knurled screw 28. The drive connection from the envelope machine is maintained, in spite of the adjustment, by an arrangement comprising plates 36, 41 the ends of which are pivoted together by a bolt 37. The other end of the plate 36 is pivotally mounted on a sleeve surrounding the shaft 32 and the other end of the plate 41 is concentric with the pinion on the envelope machine. This pinion meshes with a gearwheel 39 rotatable on the bolt 37 and the gearwheel 39 in turn meshes with a gear-wheel on the shaft 32. In a modification the cam drive may be dispensed with and to kinetic energy in the moving envelope relied on to flex the leaf springs.