Patent GB-109130-A (GB)
Title: Method of Folding Paper for and Machine for Making Block-bottomed or Square-bottomed Bags.
IPC: B31B29/00
Filed: 1916-10-04
Abstract: 109,130. Bibby & Baron, and Denman, W. Oct. 4, 1916. Paper bags, making.-In a machine for making squarebottomed bags, the first fold a<8>, Fig. 34, for the tube length, and' the folds a<5>, a<7> for the first half-diamond are formed simultaneously; after forming the second fold a<10> to complete the tube length, the second half-diamond is formed and the first half-diamond is completed simultaneously, and devices such as the guides described below are provided for turning over the folds a<13>, a<14>, Fig. 10, to complete the bag. In the machine shown, a web a, Fig. 4, guided by rollers b<1> - - b<3> is fed by rollers f, f<1>, c, c<1> and is cut into lengths by a rotating knife d and a fixed knife d<1>. Guidewires c<2>, c<5>, f<2>, f<5> and lips c<6> are provided. The device for forming the fold a<8>, and the first halt-diamond consists ot a plate g provided with a triangular flap g<5>. Fig. 17, hinged at g<6>, the edge g<5x> of the flap coinciding with the edge g<x> of the plate when the flap is turned down. The plate g is mounted on an arm g' operated by a cam g<4>, a finger g<7> on the flat engaging a camslot which lifts and depresses the flap as the plate is moving to the right and left respectively. Initially, the plate g is at the right, Fig. 4, with the flap raised, and as each sheet is advanced by the rollers f, f<1>, means such as counterweighted fingers. f<6> turn the end of the sheet towards the flap. As the plate moves to the left, the flap is depressed, and a device such as a cam-operated arm h tucks the sheet between the plate and the flap. the folds a<8>, a<7>, a<5>, Fig. 34, being formed or determined by the forward edge of the plate, the edges g<5>, g<3x>, and the arm h respectively. The folds are completed by rollers i, i<1>. The first and second half-diamonds may be formed while the sheet is passing along a single plane, but are preferably formed while the sheet is passing along two different planes, which may be superposed or, as shown, at right-angles. The second fold a<10> may be formed by a vertically reciprocating dipper which transfers the sheet to rollers i<1>, i<5>. The sheet is thus turned into the vertical plane, as shown at A, Fig. 10, and is fed along between a plate l and a. bar I' by pairs of rollers k, k<x> - - k<5>, k<5x>. The device for forming the second half-diamond and completing the first consists of a triangular flap m<1>, Fig. 10, hinged at m<2> to a plate m, the inclined edge m<x> of the plate and the edge m<1x> of the flap coinciding when the flap is turned down. The plate m moves on the plate l and is constrained by the engagement of pins m<7>, m<8> with slots m<4>, m<5> in the plate l. An arm n, rocked intermittently by gearing, is slotted to engage a pin m<6> which enters a slot m<3> in the plate l and is secured to a slide mounted on the plate m and formed with teeth gearing with the hinge-pin. In operation, the plate m and flap m<1> enter the slightly gaping end A, Fig. 10, of the bag, and the slot m<3> then causes the flap to open outwards against the bar f<1>, the bottom of the bag being given the form shown at B. The bag is completed by turning over the folds a<13>, a<14>, preferably by means of ploughs q, q<1> which co-operate with depending arms p<2> on a plate p. The completed bag C is delivered to conveying or aasembling mechanism. A mutilated roller b. Fig. 4, applies dabs of paste near to the side edge of the sheet, and a roller t<1> applies a line of paste a<3>, Fig. 34. The leading edge of the sheet, after passing through the rollers i, i<1>, is lifted against the roller t<1> bv a frame secured to a shaft which is rocked periodically by a connexion to the cam shaft. The roller t<1> is operated by ratchet gearing timed so that the roller is rotated when the dipper is rising. The rollers k - - k<5x> are acted upon by springs adjustable in boxes r formed on a frame which is supported by bars r<2>, r<3>.