MACHINES FOR PRODUCING ENVELOPES

摘要

1342207 Making envelopes K H HONSEL 23 Feb 1972 [23 Feb 1971] 8373/72 Heading B5D In a machine for producing envelopes with two closure flaps 8, 9 provided with self-seal adhesive, Fig. 3, by folding adhesively coated and side folded blanks along fold lines I, II and III using co-operating rotatable folding tongs, such as 14, 141, and blades, such as 13-13111, a lower closure flap 8 of each blank is folded anticlockwise about the fold line I and then, in turn, the envelope back panel situated between fold lines I and II, and the portion of the blank between the fold line III and the long edge of the lower closure flap are folded clockwise about fold lines II and III respectively. In one embodiment, Fig. 4, the blank is fed, with its lower closure flap 8 leading between the nip of folding cylinders 10 and 11. Folding blades 13-13111 co-operating with tongs 14, 141 fold the blank about the fold line I. As the remainder of the blank passes between the nip of cylinders 10 and 11, further folding blades 16, 161 and folding tongs 15-15111 co-operate to fold the blank about folding line II. The folded flap 8 is pressed into contact with the adjacent back panel of the blank which in turn is pressed against the front panel by a pressure plate 16a and a pressure belt 17 which has a greater linear speed than the peripheral speed of the cylinder 10. The blank is then fed, fold line II first, into the nip of a further folding cylinder 12 and the cylinder 10. Suction means 20, 21 hold the lower closure flap and the back panel portions of the blank against the cylinder 12 as folding blades 19, 191 and tongs 18-18111 fold the blank about fold line III. Each completed envelope is then gripped on a drum 22a and then conveyed between belts 25, 26 to a cylinder 27 having grippers 28-28111. A table 29 receives the envelopes from the cylinder 27 in the orientation shown. In a further embodiment (Fig. 5) after being folded about lines I and II as before, each blank is gripped by a direction changing cylinder (38) and then by a folding cylinder (42) to be drawn into the nip of the folding cylinder (42) and a further folding cylinder (43). Co-operating blades (45, 451) and tongs (44-44111) of the cylinders (43 and 42) form the fold about the line III. The completed envelopes are then conveyed to and deposited on a table 29.