| 摘要 |
1445567 Laminates SOLAR THOMSON ENG CO Ltd 26 July 1973 [11 Aug 1972] 37679/72 Heading B5N [Also in Division D1] A conveyer belt comprises a body of flexible plastics material or rubber having embedded therein at least two sheets of fabric which are coextensive longitudinally of the body and at least partly co-extensive laterally of the body and spaced apart in the direction of the thickness of the body, each of the sheets including a plurality of laterally extending flexble filaments arranged in two layers, the laterally extending filaments having a modulus of elasticity exceeding 104 lbs./in.<SP>2</SP> and a diameter exceeding 0À001 inch, the rubber or plastics material penetrating the fabric to bond with the filaments. The fabrics may be woven, non-woven or knitted but are preferably woven fabrics in which the filaments 10 are disposed in two layers having spacing strands 12 extending between the two layers and lacing strands 3 passing through the layers and around the filaments. The filaments are preferably in the form of yarns spun or twisted together, the twist and/or crimping of the filaments being kept to a minimum. The filaments which may be of metal, nylon or polyethylene terephthalate, may have a breaking stress of 50,000-100,000 lbs./sq. inch and an extension at break of 5-20%. The belt may be produced by treating the fabric with a bonding agent and then with a thin layer of rubber, applied by spread coating or calendering, calendering on a sheet of rubber which will constitute the external belt cover, placing the resulting assembly with the cover face down on a table, placing on it a further sheet of rubber and another piece of the assembly with the cover facing upwards, applying pressure by means of a press or rollers to effect bonding, and heat and pressure in a press to effect vulcanization. The transverse rigidity of the belt may be varied by including additional layers of fabric of different widths in the assembly, by decreasing the distance between the sheets from the centre towards the edges, by increasing the rigidity of the rubber between the sheets at various positions or by crimping the fabric sheets at selected positions. Pairs of projecting ribs may be provided near the edges of the belt for receiving rope, the belt being supported and driven by two rope circuits, one on each side of the belt. |
