Patent GB-191000881-A (GB)
Title: Improvements in Machines for Making Block Bottom Paper Bags.
Inventor: BOOTH FRANK
IPC: B31B3/32
Filed: 1910-01-13
Granted: 1911-01-13
Abstract: 881. Booth, F., and Mallaber, H. Jan. 13. Paper - bags, making. -In a machine for making block-bottomed bellows-sided bags, mandrels or formers 10, Fig. 10, are secured at right-angles to a vertical face-plate 9 which rotates intermittently and conveys the bag past the various folding and pasting devices. The cut blank, with or without a lining, is placed on the feed-table 44, and is fed forward into the machine bv reciprocating fingers 54. The blank, when in the machine, is supported by a fixed inclined plate 69, and by a spring-supported flap 45 pivoted to the front of the table 44. The former 10 moves from position 1 to position 2 and during the movement, one side of the bag paper is turned against the inner side of the former by a circular plate 84 fixed to the plate 69. Immediately this side is turned up, it is also folded over the top of the former and held there by a pivoted folder 87. After passing the flap 45, the free side of the paper hangs down in a sloping position while the edge is pasted by means of a revolving paster 99 which takes paste from a feeder 100. While it is being pasted, the edge of the paper is supported by a bar 104 carried by pivoted lever arms 105. One of these arms has a tailpiece lying in the path of that part of the bag paper which projects over the top of the former. Thus, if a blank is not fed into the machine, the tailpiece is engaged by the paper, and a counterweight holds the bar 104 out of the path of the paster 99. As the former moves on to position 3, the paper is folded round the outer side by a fixed curved plate 110. In position 3, the wrapping-operation is completed by rollers 113, which fold the paper over the top of the former and press the pasted edge. The folder 87 is momentarily moved out of the way of the rollers 113, and then resumes its position pressing the paper against the former. Also, while the former is in position 3, the paper is pressed against it by a weighted plate 144 and by spring plates. Immediately the wrapping-operation is completed, one side of the projecting ends of the paper is folded down by a device consisting of a plate 151, Fig. 26, jointed at 152 to the end of a small spring-supported lever which is pivoted in the end of a sliding rod 156. Two flap plates, which press out the ears of the bag, are pivoted beneath the sides of the plate, and are connected by a coiled spring 169 which also forms a paster for applying paste to the upstanding side 21 of the bag. The pressure of the plate causes the two plates to turn and press the wings outward. The former now moves forward to position 4, Fig. 10, and this movement folds down and presses the upstanding edge 21 of the bag by contact with a fixed plate. The pressure is maintained until the bag almost reaches position 5, whereupon the tabs are turned outwards by stationary curved guide plates 177, 178, are next pasted, and are then folded down against the bottom of the bag by stationary inclined plates 184, 185. While moving from position 5 to position 6, the edges of the bottom fold of the bag are pressed by resilient rollers, and at position 6 a plate 193 presses the bottom and maintains the pressure until the bag reaches position 7. The plate moves away, and the bag is removed from the formers by horizontally reciprocating strippers 195, which push it into a folding-box consisting of fixed top and bottom plates 226, 227, Fig. 37, each with a longitudinal groove 228. Folding-plates 230 pass through these grooves and press in the bellows side of the bag. The sides of the box move inwards as the sides are pressed in and collapse the bag. The bottom of the folded bag is pressed by a reciprocating tucker blade between two pressing-rollers which draw the bag from the box and deliver it from the machine.