Patent GB-640990-A (GB)
Title: Improvements in or relating to filled bag closing machines
IPC: B65B7/08
Filed: 1947-07-29
Abstract: 640,990. Packing. CONSOLIDATED PACKAGING MACHINERY CORPORATION. July 29, 1947, No. 20411. Convention date, June 23, 1943. [Class 94(i)] A filled bag closing machine for forming a filled paper bag into an extremely slack package, includes means for forming a transverse tuck in the collapsed unfilled mouth portion of the bag, means for forming a transverse tuck in the bag neck only above the tuck and means for releasing the tuck subsequent to the formation of the closure to return the bag to slack-filled condition. The closure is effected by stages at stations A, B, C, D, and E, (Fig. 1, not shown) the bags being conveyed to succeeding stations by means of a pusher provided at each station, and held in a stationary position during the time necessary for operation of all the stations. At station A gusseted 'side walls of the bag are tucked inwardly and the front and rear walls collapsed thereupon by a pair of plates. Forming tuck in bag mouth (Fig. 2). A bag 14 is moved along a table 12 by a pusher so that the upstanding collapsed mouth part (shown dotted at 64) is located between two spaced plates 46, 48. By means of cam mechanism (not shown) a tucker blade 42 carried by a carriage pivotally supported by links 26, 28, is moved horizontally from the dotted line position 44 to that shown in full lines so as to form a transverse tuck 43 in the neck of the bag between the blade 42 and a rod, the bent-round end 56 of which is secured to a bracket 60. The bag mouth is thus shortened from the height shown in dotted lines at 64 to that in full lines at 66. Creasing, trimming and forming first fold. The tuck 43 is maintained throughout the remainder of the closing operation by means of a retaining blade 68 (Fig. 3) which is in vertical and horizontal alignment with the forward position of the tucking blade 42 and extends the length of the rest of the machine, as does the bar 56. At station C (Fig. 3) the end of the bag is trimmed by means of fixed and movable shearing blades 78, 73 respectively and provided with a crease line 72 by means of a creasing die 76 carried by a pivoted arm 74 and co-operating with a stationary die 70. A curved folding blade 84 is then moved forwardly in an arcuate path to fold the bag along crease line 72 over an elongated guide rail 86, as seen in Fig. 4 (not shown). The creasing, trimming and folding mechanism is actuated by cam mechanism (not shown) and if desired the bag mouth may be provided with a second transverse crease as described in Specification 639,582. Glueing and forming final closure. Between stations C and D the bag is traversed past a glue-applying wheel (Fig. 5, not shown) which applies a band of adhesive to the bag neck (as at 90 in Fig. 6) and a plug of adhesive to the edges of the lip of the bag (as at 92, Fig. 6). At station D further adhesive is applied by a glue blade 94 which is projected into contact with the upper half of the tuck 43 which is supported by the retaining blade 68. A finger 96 acts to retain the lip within the fold formed when a folding shoe 98 having a channel portion 100 moves to the left towards the position of Fig. 7 (not shown). The glue blade 94 and finger 96 remain in position to ensure the correct location of the lower fold line until just before a horizontal portion 102 of the shoe 98 is brought into contact with the upper surface of the closure, when they are withdrawn. Drying adhesive. The next movement of the conveyer pushes the bag 14 to the position shown in Fig. 9, the horizontally disposed bag closure being slid beneath the curved edge 108 of a guide shoe 106 and between a pair of horizontal gripping members 110, 112. The upper member 110 comprises a plate 126 with a flange 128 and is pivotally supported at the end of a lever 114 which is urged downwardly by a spring 124 acting through a rod 116 so as to grip the bag closure and support the bag while in the drier. The drier E (Fig. 1, not shown) comprises a plurality of gripping members 110, 112 with levers 114 arranged radially of a wheel like structure supported for rotation on a central shaft. Cam and follower mechanism (not shown) is provided to raise the levers 114 against the springs 124 to permit insertion of a bag closure and to permit the bag to drop into a shoot after completion of one revolution. Each bag is thus in turn delivered to and removed from the drier the number of gripping units being arranged to permit setting of the adhesive during the time of one substantially complete revolution of the wheel. In order to ensure rapid and uniform discharge of the bags into the shoot, when the gripping members are released, the lower member 112 consists of an anvil plate 134 pivotally supported in parallel relationship with a spoke part 132 which is fixed relative to the wheel. Thus the plate 134 has perforated ears 138 (Fig. 10) through which extends a rod 136, and a spring 140 (Fig. 9) tends to hold the plate 134 in a horizontal position. When the upper gripping member is raised, however, the weight of the bag will cause slight rotation of the plate 134 about rod 136 against the action of the spring 140, and this action eliminates the tendency of the bags to continue hanging from the plate due to the inherent stiffness of paper. An adjustably mounted stationary cam 142 serves to level the upper gripping member just prior to and in order to facilitate the entry of the bag thereunder.