| 摘要 |
<p>1458380 Roller extrusion die UNIROYAL Inc 19 Nov 1973 [20 Nov 1972] 53577/73 Heading B5A An elastomeric material tyre tread blank, having feathered edges, is extruded from an outlet 126, Figs. 2 and 3, of the same shape, defined between the cylindrical surface of a driven roller 116 and the downstream end of a stationary surface 120 of a member 122, which defines with the roller 116 a passage 125 which tapers towards the outlet, the material being delivered to the passage 125 from a screw extruder, along a passage whose width increases in the direction parallel to the axis of the roller, and whose transverse thickness decreases. The driven rotation of the roller 116 enhances the extrusion pressure of a screw 106. The elastomeric material may comprise synthetic rubber, or natural rubber which may be blended with synthetic rubber or synthetic resin, or a synthetic elastomeric resin. The member 122 is replaceably mounted for cleaning, and is vertically adjustable to vary the clearance to the roller 116 on which it bears at each side at bearing members 123. The roller 116 is cooled by water circulated along a helical passage 136, via inlet passages 140, 138, and outlet passages 144, 142, and is rotated via a belt and pulley drive to a variable speed gear-box. The passage of increasing width and decreasing thickness, Figs. 7-14 (not shown), is of constant depth across its width, Fig. 15, at section 15-15, Fig. 2, at the location of delivery to the roller 116. In the Fig. 2 embodiment, the surface 120 is arcuate or linear in the extrusion direction, and a surface 118 upstream thereof which is arcuately curved in the extrusion direction, is also curved arcuately in the transverse direction, Fig. 4 (not shown), to provide a smaller depth towards the centre of the passage which it defines with the roller 116. In the Fig. 17 embodiment (not shown) the material is delivered from a vertically oriented extrusion band, and the surface of the roller is cleaned downstream of the outlet by a threadedly adjustable blade. In the Fig. 18 embodiment (not shown) the material is delivered upwardly to a passage defined between a lower stationary die surface, and an upper roller.</p> |
