GB1209938A - Bag-making machines incorporating means for checking the bag closures - Google Patents

Abstract

1,209,938. Discarding from bag-making machines. WINDMOLLER & HOLSCHER. 24 Nov., 1967 [28 Nov., 1966], No. 53644/67. Addition to 1,122,788. Heading B5D. [Also in Division G1] Discard from a bag-making machine of bags with improperly formed block-bottoms is controlled by means checking the inclined edges 192, 199 (Fig. 6) of the bag bottoms. The edges may be checked by mechanical feelers, by photo-cells, which may co-operate with reflectors which slide under the portions 192b at the flaps, or by beta waves from a cobalt source. In the machine described, the bags move transversely, as indicated by the arrow 189, and photo-cell checking devices 185, 186, 194, 195 are arranged for occlusion or exposure at moments correlated with the exposure or occlusion of corresponding photo-cells 187, 198, 193, 200 detecting the leading and trailing sides of the bags. Operation of the photo-cells associated with the leading inclined edge 192 by passage of the trailing edge 199 is prevented by cam-operated switches synchronized with the bag conveyer. Further detectors (162), (163), (Fig. 1, not shown) detecting opposite ends of the bag sides detect a bag incorrectly oriented in its passage through the machine. When improper folding results in the difference in thickness between opposite halves 229 231 (Fig. 9) of a bottom being greater than normal, this may be detected by rollers 223, 224 which tilt about a central shaft to cause an arm 236 to release a switch 238. To facilitate adjustment of the checking devices for different sizes and shapes of bag, they may be mounted in sets on carriers which are moved conjointly laterally of the conveying path by oppositely handed lead screws. The detectors such as 187 (Fig. 6) detecting the bag sides may be movable in the direction of conveyance, and scales may be provided for all the adjustments to indicate the corresponding bag dimensions.