| 摘要 |
<p>1280528 Coating cores by extrusion INDUSTRIE PIRELLI SpA 15 July 1969 [2 Aug 1968] 35461/69 Heading B5A A band of uncured elastomeric material having embedded therein a plurality of longitudinally extending parallel reinforcing wires is formed using an extrusion die head 1 comprising inlets 16, 17 for the elastomeric material, guide tubes 20 for the reinforcing wires and an extrusion orifice 18. In the embodiment shown, inlets 16, 17 communicate with screw impellers (2<SP>1</SP>, 2) respectively, Fig. 1 (not shown), and the wires (3) are fed from bobbins (4) on a shaft (5). In an alternative arrangement, Figs. 3 and 4 (not shown), die head 1 is fed via a single inlet (32) from an extruder (25) having a central outlet (31) and a single screw (26) having flights (27, 28) of opposite hand. Orifice 18 is preferably shaped to compensate for pressure differences across the orifices, and as shown, has a lesser depth at either end. The distances between guide tubes 20 need not be constant. In a modification, not shown, a single extruder delivers elastomeric material via an inlet located in the wall opposite the extrusion orifice, the wires following a non- linear path through the die head.</p> |
