Patent GB-640936-A (GB)
Title: Improvements in or relating to method and apparatus for sealing filled bags
IPC: B65B7/08
Filed: 1947-07-24
Abstract: 640,936. Sealing bag mouths. CONSOLIDATED PACKAGING MACHINERY CORPORATION. July 24,1947, No. 19882. Convention date, Feb. 2, 1940. [Class 94(i)] A method of sealing a filled bag comprises tucking the side walls of the unfilled mouth portion of a bag inwardly between the front and rear walls of the mouth portion, collapsing the front and rear walls upon the side walls, and inserting adhesive between the opposed inner edges of the collapsed bag mouth to seal the mouth in closed position. As applied to the bag closing machine described in U.S.A. Specification 2,175,557, the bag is supported at a preliminary folding station, Fig. 4, with its collapsed mouth portion 22 lying between longitudinal guide elements 23, 24. A male creasing die 26 carried by an arm 27 connected by linkage 29, 32 with a pivot shaft 33, supported by the frame, is reciprocated by the action of a link 34, pivotally connected with the links 29, 32 and operatively associated with a cam shaft (not shown). A fixed female creasing die 25 co-operates with the die 26. The frame 12 carries a blade 35 which co-operates with a movable blade 36, carried by a slide 37, reciprocated by the action of linkage 38, 40, 42, 43, operatively connected with suitable cam mechanism (not shown). A folding blade 46 has a downward extension 48 which is pivotally mounted on a pin 49 carried by the slide 37. A tension spring 50 is connected between a lug 51 on the slide 37 and the extension 48, and urges the slide 37 clockwise into the position shown in Fig. 4. An ear 52 carried by the extension 48 is slidable on a rod 53 between stops 55, 57. In operation of the folding mechanism, following inward movement of the creasing member 26 to form a crease 22a (Fig. 5) in the mouth 22, the slide 37 is reciprocated to cause the blade 36 to trim the edge of the mouth 22. Towards the end of the travel of the slide 37, the ear 52 strikes the stop 57 with an impact which results in counter-clockwise movement of the folding member 46, a downward extension 47 of which thus folds the mouth portion 22b about the guide element 24. In passing to a final folding station, by means of a conveyer (not shown), the outer end portion 22c and the portion 22d of the mouth 22, are engaged respectively by adhesive-carrying rollers 89, 90 (Fig. 7), which deposit strips of adhesive 94, 95 (Fig. 10) respectively. The glue at 95 is drawn into the mouth by capillary action. Adhesive 80 is transferred from a reservoir 79 to the rollers 89, 90, by respective roller trains 83, 81 and 84, 82. The rollers 81, 82 are carried on a stub shaft 77 driven by a chain drive (not shown) from a drive shaft of the machine and the rollers 83, 84 are driven by a belt drive 86 from the shaft 77. The rollers 89, 90 are driven by a belt drive 92 from the shaft carrying the rollers 83, 84. At the final folding station, a folding member 97, has an initial downward movement in which a channelled portion 99 thereon is guided (by means not shown) into engagement with the mouth 22. At the same time an adhesive carrying blade 96 moves in the direction of the arrow (Fig. 10) until its extremity reaches the apex of the angle formed between the bag shoulder and the mouth 22. The blade 96 in its return movement deposits adhesive on the bag shoulder and is followed by the folding member 97, a horizontal portion 100 of which engages the mouth 22 and turns it down and presses it against the adhesive-coated shoulder. In an alternative method (Figs. 15-17, not shown), adhesive is introduced from a nozzle into the opening of the bag mouth when it is held vertically and unfolded by the elements 23, 24. The nozzle may traverse the length of the fold or alternatively may be equal in length to the fold. Adhesive is then coated on the bag shoulder as before by a blade and the mouth is folded down by a member which is similar to the member 97 but has no channelled portion.