Patent GB-977298-A (GB)
IPC: D21J1/16
Abstract: 977,298. Laminates and laminating; slitting. CORRUGATING TECHNICIANS Inc. Dec. 11, 1961 [Dec. 14, 1960], No. 44173/61. Headings B4B and B5N. [Also in Division B6] Laminating apparatus for making corrugated paper board having a paper layer on one or both sides of the corrugated layer is provided with devices for maintaining alignment of one of the edges of the constituent webs, the expense of trimming that edge of the product being thereby avoided. As shown, Figs. 1A and 1B, a paper web 10 drawn from a roll 11 passes around rollers 14A, 14B, 15, 18A and 18B, is corrugated by passage between heated fluted rollers 25 and is coated by a roller 26 with adhesive for the combining therewith of a plane paper web 20 supplied from a roller 21 and around rollers 24A, 24B and 27. The composite web 35, which is carried over rollers 28A, 28B, may be used as such or may be combined with a third web 30 of plane paper supplied from a roll 31 and around rollers 34, 36A and pressed by roller 36B to the free side of the web 35, the corrugations of which have been adhesive-coated by a roller 46 adjacent to pressing rollers 44, 47. The three-layer laminate 45 is consolidated by passing between a plate 48 and pressing rollers 49. The two- or three-layer products are slit by circular knives 65 adjustable, as by set-screws on a shaft 60 according to the width of product desired, and, as shown, three shafts such as 60 are carried between triangular frames 61 which are rotatable on control pivots to bring any pre-adjusted set of knives into operation as desired. The control mechanism for maintaining edge-alignment of the webs 10, 20 comprises sensing fingers 51-1, 51-2 bearing against the controlled edge of web 20 and composite web 35 respectively and connected to vacuum valves 50-1, 50-2 in which vacuum is maintained by an exhausting device 57A. The valves 50-1, 50-2, shown as 50 in Fig. 2, are laterally adjustable, to determine the position of the edges of the webs, along calibrated shafts 55 by screw and nut mechanism 53, 54, 56. Pneumatic lines V-1, V-2, Figs. 1A and 1B, connect the valves 50-1, 50-2 to hydraulic valves R-1, R-2 forming part of hydraulic circuits supplied by a pump 58A from a reservoir 59A. The circuit of valve R1 connects the valve to the near side of an hydraulic cylinder F-1 forming part of a device for displacing web 20, and to the far side of a similar device F-2 associated with composite web 35, the other sides of F1 and F2 being connected together. Thus lateral movement of web 20 affects the setting of valve R1 and produces corresponding movement of web 35. At the same time valve 50-2 is affected by movement of finger 51-2, changes the setting of valve R2, and creates movement of an hydraulic device FA, resulting in adjustment of roller 15, which supports web 10, about a pivot 16, thereby adjusting the position of the edge of the web. Similar mechanism, embodying sensing devices 51-3 and 51-4, hydraulic valve R3 and displacing means F-3, F-4, is provided to maintain alignment as between webs 35 and 30, movement of the webs resulting in actuation of a fourth valve R4 and adjustment of a laterally-movable bridge 40 carrying rollers 41. The bridge may also carry an alternative set of rollers 42. A further control mechanism comprising sensing finger 51-5, pneumatic valve 50-5 connected to hydraulic valve R-5, and hydraulic cylinder FC adjusts the knives 65 in relation to the controlled edge of the completed web by moving the frame members 61 laterally on rails 63. Limit switches 13, 23, 33 operating reversible electric motors, are provided to adjust the position of the rolls 11, 21, 31 to within the range of the edge control mechanism, and a rotary knife may be provided at the controlled edge to be brought into operation should the control on the knives 65 fail.