| 摘要 |
<p>939,588. Extruding nets. E. I. DU PONT DE NEMOURS & CO. Nov. 21, 1961 [Nov. 25, 1960], No. 41530/61. Class 87(2). Plastic net-like structures consisting of more than two layers of parallel homogenous strands, e.g. 34a, 35a, 36a, Fig. 7, are manufactured by extruding the plastic from three or more dies 31, 32, 33, Fig. 8, moving relative to each other. When two or more sets of dies are in register, integrally extruded intersections are formed, either unitary, 37, Fig. 7, or multiple, 39, Fig. 9. The netlike structures may be either sheets, when the dies have a reciprocatory movement, Fig. 8, or tubular, when the dies have a rotary movement. Figs. 1 and 2 show an apparatus for manufacturing a tubular net. Plastic is fed through tube 1 into the cavities 1a and 1b and is extruded at the base of the assembly through the grooves (shown dotted) in the rotating parts 4 and 5, and through the grooves 12 of the stationary port 8. Specification 836,555 is referred to.</p> |
