GB1427827A - Extrusion of articles having a web and a pair of integral flanges - Google Patents

Abstract

1427827 Drawing and extruding metals DAVY-LOEWY Ltd 15 Oct 1974 [15 Oct 1973] 47969/73 Heading B3P [Also in Divisions B4-B5 and E1] An article comprising a web 38, Fig. 4, having a transverse integral flange 40, 42, at each end, is made by delivering material through a chamber 10, Fig. 2, defining the shape of the flange 40, and through the orifice 14 of a die 12 defining the shape of the stem, into a chamber 20 defining the shape of the flange 42, and then displacing the chamber 20 downwardly away from the die 12, Fig. 3, whilst continuing delivery through the orifice 14 to extrude the stem 38. Upon terminating movement of the chamber 20, delivery of material into the chamber 10, and extrusion, is terminated by obturating inlets 8 to the chamber 20 by the sliding of a shear plate 16, the flange 40 then being removed from chamber 10 upon movement apart of two parts of the die 12 defining the orifice 14, and recommenced movement of the chamber 20. The material may be delivered by injection directly into the chamber 10, or by injection through holes 28 into a chamber 4 from which delivery is then effected to the chamber 10, through the inlets 8, by displacement of a pressure plate 6 by a plurality of rams 7, actuated hydraulically, electrically, or mechanically. The shear plate 16 comprises holes 31, slidable into and out of alignment, with the inlets 8 by an hydraulic unit (17) Fig. 1 (not shown). The chamber 20 is defined in a member 18, displaceable upon a platform (not shown) to which it is keyed so that, after the article is formed and has been supported by a plate of corresponding shape, the article and member 18 are pivoted through 90 degrees for horizontal ejection of the article, Fig. 4, by an ejector plate 22 actuated by cylinders 24. The material may comprise metal, or plastics or, as in the described embodiments, glass reinforced cement or gypsum plastic, which is delivered as a slurry to the chamber 4 in which it may be de-watered or de-aired prior to extrusion. Whilst still deformable, the article may be further pressed or vacuum formed, The article may comprise a wall panel, Fig. 5 (not shown), or a staircase unit, Fig. 6.