Patent GB-1286312-A (GB)
Title: Apparatus and method for working on sheet material
IPC: B65H45/101
Filed: 1969-10-28
Abstract: 1286312 Cutting apparatus GERBER GARMENT TECHNOLOGY 28 Oct 1969 [5 May 1969] 52720/69 Heading B4B [Also in Divisions D1-D2] An apparatus for cutting a lay-up of sheet material 14 comprises a material support means 38, a piece of substantially air-impervious sheet material 96 adapted to overlie at least a portion of the exposed surface of the lay-up when spread over the supporting surface, and means 45, 46 for producing a vacuum under the piece of airimpervious sheet material and which acts on the air-impervious sheet to pull it toward the supporting surface so as to compress the lay-up of sheet material between it and the supporting surface. The apparatus includes a cutting tool, e.g. a reciprocable knife blade 19 driven by a drive unit 76 which is mounted for transverse movement on a carriage 78 which is movable longitudinally of a table 12 by means of a motor 84 and rack-and-pinion drive 86, 72. The table 12 includes a support 20 on which is mounted a perforated plate 32, e.g. of expanded metal, partitions 34 being located beneath the plate and support to form spaced chambers 36. A bed 38 of a penetrable material, e.g. of a cellular polyethylene is mounted on the plate 32. A valve member 50 is mounted in each chamber 36, the separate valve members being actuated by cam surfaces 86, Fig. 1, on the carriage 78 so as to allow the chambers to be connected to a vacuum source via a duct 46 and pipe 47. The bed 38 is made porous either by means of an open cellular structure or by means of holes 44 provided therein. Before a cutting operation, layers of material e.g. fabric, is fed from a roll 64, Fig. 1, which is mounted on a carriage 73 moved back and forth across the table, each successive layer being held by suction as the valves 50 are actuated by means of cam surfaces 74 on the carriage 73. After the material has been laid on the table, a sheet 96 of a non-porous material, e.g. plastics, is placed over the fabric so that as the cutter carriage 78 is moved along the table a suction is drawn through the fabric material which, due to the sheet of non-porous material, is compressed into a relatively rigid condition thereby facilitating cutting. In addition to the sheet 96, endless belts 90 of a non-porous material are mounted on rollers carried by the carriage 78 so as to move in contact with the fabric material; the belts are movable upwardly to accommodate different thicknesses of material. In a modification a single endless belt may be used (Fig. 9, not shown). In further modifications, the cutter is moved in the transverse direction only, the fabric material together with the penetrable bed (106, Fig. 5) being moved longitudinally by means of endless belts (112, 114, 116), the belt 112 being made porous so as to permit a vacuum to be drawn through the fabric material; instead of the cutter being of a reciprocating- blade type, it may be replaced by an endlessband type (Figs. 6 and 7). In the modification shown in Fig. 8, the bed of penetrable material 260 is mounted on a porous drum 258 within which a vacuum is applied.