GB978042A - Glass fibre mat and method and apparatus for its manufacture - Google Patents

Abstract

978, 042. Wadding; forming fibrous mats; agglutinated fibrous sheet materials. OWENS-CORNING FIBERGLAS CORPORATION. Sept. 27, 1963 [Oct. 18, 1962(4)], No. 38249/63. Headings D1N and D1R. A glass fibre mat, Fig. 7, comprises a band 62 of glass fibres laid in zig-zag form from one side of the mat to the other successively in the direction of the length of the mat, the band 102 comprising a plurality of parallel strips each formed of a strand a, b, c, d of glass fibres arranged along the band in substantially flat overlying loops. The band 102 tapers towards the side edges from the longitudinal centre line thereof. Continuous glass filaments 23, Fig. .1, are drawn through the orifices of bushings 21, 22 depending from glass melting tanks (not shown) and size is applied thereto by applicators 25. The filaments from each bushing are then grouped together to form a set of six strands individually segregated as they travel within six grooves in a gathering shoe 27. The sets of strands 29, 30 pass under grooved aligning shoes 31, around idler wheels 33 and around pull wheels 35, 36 driven by motors 37, 38. The shoes 31 may be given a slight traversing motion to slowly shift the strand position on the wheel 35, 36 to help keep them clean of size and distribute the wearing action of the . strands. The wheels 35, 36 are similarly constructed but relatively reversed in position and each carries on an independently mounted oscillating back plate thereof a spoke wheel 39, 40, respectively, to project the strands tangentially therefrom. The back plate 42 of the wheel 36 is oscillated by an arm 43 driven by a fluid cylinder 52 through a link rod 54 and a triangular link 45 pivoting on a bar 47 on a base 49 and the back plate 41 of the wheel 35 is driven by an arm 57 through a connecting assembly 55 including a turnbuckle 56. The groups 58, 59 of strands from each wheel 35, 36 are accumulated in a mat 60 on a conveyer 61 of carbon steel chain construction. Adjustable shields 62, 63 define the edges of the mat 60. To prevent adherence of the strands to the shields 62, 63 nozzles 62n, 63n feed water on to the upper surface of strips 62s, 63s of open-cell foam or cotton rag material to uniformly distribute a water film flowing down the shield surfaces. Preferably twelve pull wheels arranged in six pairs are provided but they need not all be utilised. Twelve or up to thirty stands may be provided in a set drawn from each pull wheel. A shaft 67, Fig. 3, carrying the wheel 35 on a threaded stud 71 is driven from the motor 37 by toothed pulleys 64, 66 and a segmented belt 65. The wheel 35 is formed with slots 81 through which fingers 83 of the spoke wheel 39 successively project. The wheel 39 is synchronously driven with the wheel 35 through pulleys 89, 91 and a belt 93, the pulley 89 being mounted on a hub 73 carrying the main body of the wheel 35. The shaft 87 of the wheel 39 is carried by a back plate 41 oscillated by the cylinder 52 as described above. A shroud ring 85 curtails air flow into the interior of the wheel 35 and a baffle 95 lies beneath the slots 81 except in the region of the wheel 39. In a modification, Fig. 12, a spoke wheel 101 is driven from a pull wheel 100 by meshing gears 103, 104, 105. In a further modification, Fig. 13, a pull wheel 107 has an internal gear ring 111 mounted therein to engage a gear 112 integral with a spoke wheel 109. Each idler wheel 33 has a body 114, Fig. 14, having transverse grooves 117 therein which contain cylindrical graphite inserts 118 secured therein so that the strands have only point contact with the wheel 33. Alternatively, the wheel may be formed of metal with alternate grooves and rounded ridges. A strand deflecting device 133, Fig. 17, comprising a mesh or screen cylinder which is reciprocated synchronously with the spoke wheel 140 may be provided to cause the filaments in the strands to fuzz or disperse to some extent. A deflector 133 may be used only to disperse the strands on the top and bottom layers of the mat. Accumulation and drying of the size on the pull wheel 132 may be prevented by a nozzle 146 directing a light mist of water thereon. The strands are guided on to the pull wheel 132 from the furnace bushings by a shoe 127 which is slidable on a flat bar 130. The size applied by the applicators 25 may be water or may be a primary binder and a powdered synthetic resin may be subsequently applied. A composite mat 70, Fig. 15, passes on the conveyer 61 under an infra-red radiator 72 to partially remove moisture from the mat. The radiator 72 may include a ceramic honeycomb heated by a gas flame or electrically energized bulbs or nickel chrome rods. The mat 70 then passes onto a conveyer 74, 79 spray dry binder particles 75 upwardly to gravitate downwardly on to the mat 70. Particles not caught by the mat pass through mesh openings of the conveyer 74 into an exhaust compartment 81. The binder is the cured in an oven. Specification 770,535 is referred to.