GB1263791A - Extrusion apparatus and articles produced therefrom - Google Patents

Abstract

1,263,791. Extruding ribbed products. J. H. LEMELSON. 20 Jan., 1969, No. 3130/69. Heading B5A. [Also in Divisions B3, F2, H1 and H2] In the production of ribbed sheets, tubes and coated cores by extrusion, the extruder is provided with an extrusion orifice and co-operating stop elements such that the product may be provided with at least two ribs extending along predetermined portions of the product. In the embodiment of Fig. 1, a sheet 127 having ribs 128 is formed by vertical reciprocation of blades 121 in front of projections (126<SP>1</SP>), Fig. 2 (not shown), of orifice (126). This orifice may be varied laterally during extrusion by movement thereacross of shutters (121<SP>1</SP>) or (121<SP>1</SP>a). By suitably reciprocating one or more of blades 121 various extrudates may be produced including sheets having bosses (141), Fig. 7 (not shown), hinge like members (137) and (143), Figs. 8 and 9 (not shown), and in each case the ribs on the sheet may be grooved as at (128s<SP>1</SP>), Fig. 3 (not shown), either by further blades attached to blades 121 or by machining downstream of the die orifice. The ribbed sheet (127<SP>1</SP>), Fig. 3 (not shown), may received beam supports (125<SP>1</SP>) at gaps (130) or be folded thereat to form a container. The gaps may be formed by milling, with or without the use of blades 121. A circular disposition of blades 121 allows production of a finned tube (130<SP>1</SP>), see Fig. 10 (not reproduced). The apparatus of Figs. 5, 6 (not shown), in which die member (30<SP>11</SP>) is vertically reciprocable, may produce open netting or a sheet having superposed ribs in the form of a net as well as the ribbed sheet of Fig. 3 (not shown) with integrally formed beam supports (125<SP>1</SP>). Support plate (63) may be covered with a fluorocarbon slip agent. Further embodiments describe the coating of cores, which may comprise one or more rigid or flexible wires, rods or tubes possibly delivered directly from a further extrusion machine. In the embodiment of Fig. 11, a core 157 is provided with coverings 154<SP>1</SP> by reciprocation of blades 155, 155<SP>1</SP>. Any coating on the core between coverings 154<SP>1</SP> may be removed by wire brushes, cutters or grinding wheels 171, 171<SP>1</SP>. The covering and/or core is cut by a knife 168. Various products are shown in Figs. 12-16 (not reproduced) including an easily bendable wire (165), Fig. 15, having a covering (166). In the apparatus of Fig. 19 a plurality of electrical conductors 306 are embedded in plastics, actuation of a blade mechanism 315a-1 &c. (315b-1 &c.), Fig. 18 (not shown), for each conductor, determining the length of covering therefor and also being capable of severing a conductor when required. The conductors are forwarded by wheels 307 supplemented by guides 30511, see also Fig. 20 (not reproduced). Alternatively they may be forwarded by shaped piston-rods (342, 343), Fig. 21 (not shown), rapidly oscillated by hydraulic or electric means, e.g. magnetostrictive vibrators. In a further modification, Fig. 22 (not shown), the conductors are cut by blades (328) within the extrusion head. This last embodiment also discloses cams (333) which move to support blades (332) during cutting and blocking actions. Post-extrusion operations may include longitudinal slitting as at 352-1, Fig. 19, more than one sheet may be extruded with conductors embedded therein, with the sheets being subsequently laminated together. Generally, by suitable oscillation of the blades the ribs may be decorated, e.g. by providing teeth like those of a spur gear. Further, the blades may be rotatable as well as reciprocable to act as movable circular saw blades. All operations of the extruder may be programmed, the implementation of the programme being dependent on feedback signals indicative of the speed of extrusion.