GB830436A - Methods and apparatus for cutting sheet material - Google Patents

Abstract

830,436. Cutting apparatus. DUTFIELD, W. H. Sept. 26, 1958 [June 28, 1957], No. 20547/57. Class 31(1). A method of cutting lengthwise a length of sheet material formed with a defined lengthwise cutting path comprises feeding the material past a knife carried by an arm which is pivotally mounted to allow movement of the knife transversely of the material and which also carries guide means which engage the said defined cutting path to maintain the knife in a position to cut the material along the said path. As shown, a length of warp fabric, Fig. 1, to form scarves is provided with gaps 4, 4a in the warp to define lengthwise cutting paths and the fabric is cut lengthwise along the gaps by means of a plurality of cutting devices 10 adjustably mounted on a bar 11 by means of clamping screws 24, Fig. 4. Each cutting device comprises a collar 17 keyed on the bar 11 and having secured thereto a channel piece 19 in which is rotatably mounted a tubular upright 13 which, intermediately of its length, is embraced by a rotatable ring 25 which carries a rearwardly extending projection 26 to which is secured by nuts and bolts 126 a pair of bars 27, 28 which together form an angularly adjustable arm. The arm 27, 28 supports a block 29, Fig. 5, in which is clamped a rod 31 forming part of a fitting 32 in which is secured a rod 35 about the axis of which a casing 37 constituting a knifesupport element is freely rotatable. The element 37 has rods 39, 40 welded thereto. The knife comprises a cutting blade holder 41 consisting of a hinge having leaves 42, 43 one, 42, of which is secured to the forward edge of the rod 40. A blade element 44 having a cutting edge 45 is clamped between the hinge leaves 42, 43 by means of a pivotally mounted U-shaped member 46 operable by a trigger 47. Each cutting device also includes a guide in the form of a metal plate 51 which is welded to the rod 39 so as to be disposed in the vertical plane containing the cutting edge 45 and is connected to the hinge leaf 42 by a strut 52. Excessive swinging movement of the arm 27, 28 of a cutting device relatively to an upright 13 is prevented by engagement of the ring 25 with a securing bolt 119, Fig. 4, while excessive swinging movement of the guide 51 and its associated blade holder 41 relatively to the arm 27, 28 is prevented by means of a cord 39a tied between the rod 39 and a hook on the arm 27, 28. The fabric is fed between guide bars 67 to tensioning rollers 63, 64 carried by pivotally mounted supports 65 and then under a bar 60 to the cutting devices from which it is drawn by a roller 61 driven by an electric motor 70 through the intermediary of a clutch which is operable by means of a pivotally mounted bar 100 connected to the clutch by means of a bell-crank 102. The fabric coming off the roller 61 in the form of separate strips is rolled on storage rollers 72, 73 mounted on shafts 74, 75 driven by means of belts and pulleys from a belt member 76 mounted on the shaft of the roller 61. The opposite edge portions of the fabric are guided around a bar 91 to a pair of rollers 92, 93.