Patent GB-208051-A (GB)
Title: Improvements in machines for making paper bags
IPC: B31B3/28
Filed: 1923-02-09
Abstract: 208,051. Fricker, W. Feb. 9, 1923. Paper bags, making.-The invention relates to machines for making block-bottomed paper bags of a lined or unlined character by folding the sheet around a former. The mechanism is driven from the horizontal cam-shafts 1, 1<a> and 16, Fig. 1, and the vertical cam-shaft 107. Feeding. Two piles of blanks, one being for finings, are stacked on inclined tables 6 and sheets are removed one at a time by an oscillating suction device, pairs of sheets being pasted together before being folded. A pump 10 is secured to a side-frame 2 and its plunger-rod 11 is operated by a pivoted lever 12 carrying a roller 14 engaging a cam 15. The suction is regulated by a flat-faced valve-member 19 carried by a cylindrical member 22, Fig. 5, mounted on a rocking lever 23, driven by a rod 25 and cam 27. The orifices 17, 20, Fig. 8, in the seating 18 and valve 19 thus communicate as required. A tube 29b mounted on a sleeve 30<a> on a rod 30 is connected with the member 22 and carries a nozzle 36. An arm 37<a> mounted on the sleeve 30<a> carries a spring-mounted knife 38, so that as the suction device is moved towards the underside of a pile of blanks by means of the cam 34, the nozzle 36 secures the lowest sheet and the knife 38 perforates the sheet and forces back the remainder o.f the pile, to allow a blade 42 to separate the sheet from the pile. The blade 42 is mounted on a stub-axle 40 on the side frame 2 and is operated by the cam 49. The base of the blade 42 is provided with a curved portion 44, Fig. 3, which guides the sheet between rollers 45 carried by the blade and the driven roller 50, so that the sheet is carried on to an inclined plate 52. Pasting. Adhesive from a trough 58 is applied to one sheet A, Fig. 4, by means of a roller 63 and dabber 64, lines of paste being provided to secure one end of a lining sheet and for securing the edges of the outer sheet when it has been folded in tube form. The outer sheet A meets a lining sheet from the second feeding-device and the two sheets are pressed together by rollers 67, 68 and fed between guides 75, 76, which deliver them on to gauge-slips 81. Feeding sheets to former. Side-gauges 84, Fig. 11, guide the sheets on the slips 81, one gauge extending to the table 86. A spring finger 87 presses the sheet against this gauge and carriages 89 propelled by arms 96 and a cam 101 move the sheet forward. The rear edge of the sheet is engaged by the nose 93 and rollers 91 of the carriages 89 till the sheet is moved on to the table 86. Folding. The table 86 is raised by a shaft 102 carrying an arm 104 which engages a cam 106 on the vertical shaft 107, so that the sheets are held against a former 113. Surrounding the shaft 102 is a tube 14 carrying an arm 115 which engages a second cam 117 on the shaft 107. The upper end of the tube 114 carries plates 118, 119 which fold the sheet against the sides of the former 113. A pinion 108 on the shaft 107 engages pinions on four vertical shafts of which three only, 109 - - 111, Figs. 1 and 2, are shown. Folding plates 126, 127 are driven by cams on the shaft 16 to complete the folding of the paper round the former 113 and a roller 129 carried by an arm 128 presses the edges together. The former 113 is provided with two sets of rollers 130, 131, Fig. 14, which slightly project from the sides of the former. Rotary strippers 182, 133 on the shafts 110, 109 press the sides of the tube against the rollers 130 and move along the former. A second set of strippers combine with the rollers 131 to project a portion of the tube from the end of the former between side-plates 136, 137. Mounted on shafts 149, 151 are arms 153, 155 operated by cams 141, 143 on the shaft 16, stubs 161 - - 164 on these arms folding the end of the tube, as shown in Fig. 17. Known spring-controlled bellcrank flaps 165 - - 168 assist in folding the end. Additional strippers move the bag forward on the former. Flattening. Gusseters 178, Fig. 19, driven from a cam on the shaft 16 enter slots 140 in the side-plates 136, 137 to press the side walls of the bag inwards. Closing sectors 171, 172 operate to flatten the top and bottom of the tube and press the bottom against a presser 173 on an arm 174. This arm is driven from a cam 177, Fig. 1, by means of a lever 176 and shaft 175. A roller 189 flattens the bottom against the body of the bag. The tabs A<1>, A<2> at the end of the bag are left projecting and after paste has been applied to the bottom of the bag, they are pressed down by a plate 204 having lips 205, 206, as shown in Fig. 23. This plate is carried by a bar 207 operated by a cam 209. The bent flaps A<1>, A<2> are folded over plates 202, 203, Fig. 24, on which the bag is carried, by sliding plates 212, 213 operated by rods 214, 215 driven by a lever 218 and rod 219. The complete bag is then transferred by pressing rollers 229, 230 to a trough 234.