Patent GB-1238259-A (GB)
IPC: B31F1/28
Filed: 1969-02-28
Abstract: 1,238,259. Laminates. S & S CORRUGATED PAPER MACHINERY CO. Inc. 28 Feb., 1969, No. 10772/69. Heading B5N. In a continuous process for the production of a composite web, e.g. in the production of corrugated paper board, by advancing freshly glued travelling webs linearly while supported from below by a heated support means and engaged from above by the lower flight of a travelling belt and applying force acting downwardly against the lower flight which is transmitted therethrough to urge the webs into intimate contact with the support means, the rate of heat transfer from the support to the travelling webs is controlled by controlling the magnitude of the force acting downwardly against the lower flight, the magnitude of the force being increased as the speed of the travelling webs increases. In apparatus 10 comprising a heating section 11 and pulling section 12, the corrugated web 13 being fed in the direction indicated by the arrow A and meeting backing web 14 are supported from below in section 11 by a series of steam chests 15, 16 and 17 fixedly supported on frame members 45 and subjected to downward pressure by pressure rollers 61, 62, 63 and 64 on the lower flight of belt 20 mounted movably in plates A B and C so that an increasing number of the rollers are in their active position engaging the lower flight of belt 20 with an increase in speed of movement of the webs. In the pulling section 12 the composite web 13, 14 is drawn through the apparatus between the upper flight of belt 18 and the lower flight of belt 20 which are driven by variable-speed motor 23 acting through bevel gear means 24 and gears 25 and 26. The apparatus is provided with vertically movable horizontal frame members extending longitudinally of the heating section 11 and lifter bars 43 and 44 extending transverse to the path of movement of the webs 13 and 14 and secured at their ends to the movable frame members so as to be movable up and down therewith so that when the frame members are in their highest position the bars 43 and 44 move above the upper surfaces of steam chests 15, 16 and 17 and lift the web 13, 14 clear of the steam chests to prevent excessive heating of the web 13, 14 and belt 20 when drive motor 23 is stopped. Plates A, B and C are also mounted to the movable frame members so that when the frame members are in their lowermost position all four rollers 61, 62, 63 and 64 rest against the lower flight of belt 20 and as the frame members rise first the roller 64 is lifted in its slot so that it does not exert downward pressure on belt 20 and then the rollers 63, 62 and 61 are raised in order. The lifting mechanism for the movable frame members is controlled by switches connected in circuit with solenoids, each switch opening at a different preselected speed of operation for drive motor 23 and closing to actuate its associated solenoid and fluid-actuated power cylinder associated therewith, the rod of which is caused to move through a predetermined distance to cause frame members engaging vertically movable frame members to move horizontally, and vertically movable frame members to be lifted a predetermined amount.