GB1416937A - Machines for producing non-woven nettings - Google Patents

Abstract

1416937 Non-woven nets E SOLBECK 9 Feb 1973 [9 Feb 1972] 6609/73 Heading D1R Planar net fabrics are produced by slitting tubular nets. Warp threads 17 are conveyed by flexible tubes 18 to concentric rings 15, 16 having radially aligned grooves which space the warp threads uniformly around the circumference of heating cylinders 8. One or as shown two weft threads 21, 22 are helically wound about the tubular array of upwardly moving warp 17 by rotating thread guide 29. Autogeneous bonding is achieved if thermoplastic threads are used, alternatively glass or other threads may be precoated with thermoplastic adhesive. The tubular fabric with its rectangular mesh is then cooled by passing over first cooling ring 12 which supplies cold air from fans 13 and second cooling ring 14, through which coolant is circulated. The tubular net is longitudinally slit into two or possibly more curved sections by hot wires 30 or by rotating knives. The characterising feature of the method is that the curved nets are simultaneously made planar and bent through 180‹ and collected on rolls 46, thus reducing the height of the apparatus. Each net passes over a hollow tube 35 which is curved so as to lie in a projection of the cylindrical surface of heater 8 and is also curved symmetrically so that its ends lie below slitting means 30 whilst its center is its furthest point above said slitting means. The outer portions of the curved nets 17a are also guided by tubes 38. The upward curvature of guide tube 35 increases the path of the center portion 17b so that it travels the same distance as the outer portions 17a of the net which are moved away from the axis of the net forming machine to render the slit net planar. As each warp moves the same distance the mesh remains rectangular and strain on the bonds is minimised. Final planarity is achieved by passage over guide roll 42 which is bowed upwardly and outwardly and comprises a rubber sheath 51 journalled at intervals on curved shaft 52 each end of which is connected by a universal joint 53 to a stub shaft 54. The net is drawn through the nip of rolls 43, 44 and wound up upon storage roll 46. The orientation of guide tubes 35, 38 may be adjusted by means of turnbuckle mechanisms 37 which vary the length of guide tube 38 and struts 36, 41. Similar adjustment may be made to the orientation of guide rolls 42.