Patent GB-1514315-A (GB)
Title: Method and apparatus for the continuous manufacture of a corrugated sheet of material
IPC: B31F1/24
Filed: 1975-07-18
Abstract: 1514315 Corrugating; pile fabrics Sprl LIMATEX 18 July 1975 30204/75 Headings D1K and D1S [Also in Division B5] A flexible sheet 1 is corrugated by forming the sheet into transverse folds and projecting it longitudinally between two walls defining a passage 82 having a height greater than the thickness of the sheet 1, the walls being longitudinally displaced in the direction of projection of the sheet 1 at a speed less than the linear speed of projection, downstream portions of the walls being displaced at speeds less than upstream portions, so as to cause packing of the folds inside the passage 82 along the length of the sheet. In one embodiment, Figs. 1 and 2, a sheet 1 of oriented fibres issuing from a card 2 is steamed by jets 6, sprayed with a powederd or liquid binding agent at 3 and passes between at least one set of rotating rollers 7, 8, which may be heated, to flatten the strip and to fix or pre-fix the fibres. At the transverse folding station 5, the passage 82 is defined by three sets 11, 12, 13 of endless belts each comprising a plurality of spaced narrow tapes, the tapes of successive belts being disposed in staggered array and interdigitated with one another so as to ensure the continuity of the passage. Rolls 50, 51 project the sheet 1 into the passage 82 and act between the tapes of the belts of the first set 11, annular peripheral grooves 53, 54, 55, 56 being provided to accommodate these tapes. The speed of projection of the sheet 1 into the passage 82 is greater than the speed of the belt set 11 which is greater than that of the belt set 12. The speed of movement of the set 13 and any subsequent set may be less than or equal to that of the set 12. In the direction of movement 4, the passage 82 may converge, e.g. by the convergence of the two belts of certain sets or by step changes with the facing portions of successive belts being parallel but closer together. In the embodiment of Fig. 1, the speeds of the belts of a single set are equal. The folds of the corrugated sheet 57 are fixed by passing the strip over a rotating roller 58 to open the folds to allow a binding agent 60 to be deposited therein. The roll 58 may have a rough surface or may be a perforated hollow cylinder connected to suction means 77. The sheet 57 is conveyed by a belt 61 through a heated tunnel 62 to set the binding agent and additional binding agent may be applied at 63 and set in a tunnel 64. In another embodiment, Fig. 3 textile backings 65, 66 are applied by rolls 71, 58, respectively, to the corrugated sheet. 57 as it emerges from the tunnel 82 and are coated with adhesive at 70, 68, respectively. The laminate is driven by belts 73, 74 through a heating tunnel 75 and is split along its thickness by a device 76 to form a synthetic fur or carpet. In a modification (not shown), the corrugated sheet is provided with a lower backing 66 only and the laminate is subjected to a fold fixing treatment similar to that of Fig. 1 In a further embodiment Fig. 4, (not shown) rotatable rolls (78), (79) are disposed downstream of the rolls (7), (8) and are reciprocated along their axes so as to impart to the oriented a zig-zag movement while keeping them parallel to one another. In the passage (82), the folds are flattened by running the belts so that the speed of the upper belt of each set exceeds that of the lower belt and the speed of each belt is less than that of the belt preceding it and greater than that of the belt following it. In other embodiments (not shown), if the fibres of the sheet are fusible, they are fixed without the use of a binding agent by localised fusion, e.g. using flame nozzles. The sheet may be a non-woven or woven fabric or a foamed plastics sheet. Glass fibres are specified.