摘要 |
901,774. Drawing glass fibres. JOHNSMANVILLE FIBER GLASS Inc. Aug. 9, 1960, No. 27518/60. Class 56. Apparatus comprising a container for molten glass with a projection having an orifice from which a fibre can be drawn has a heat-reflective shield member to reduce radiant heat transfer from the bottom of the container to the end of the projection. Thus, hollow metal projections 75, Fig. 5, may be inserted in or made integral with the container 74 made of metal or clay refractory. A circular metal container may be heated by induction, a refractory one by gas. The reflective shield 73 is apertured to fit the projections. The shield is of precious metal, e.g. gold, silver, platinum-rhodium alloy, or of aluminium or metal-coated asbestos. The projections may be in circular rows in a circular container, the shield 73 being annular and, if required, water-cooled at its periphery. The projections may, however, be arranged rectangularly on a rectangular container heated by passage of a current, the shield 73 then being supported without touching the projections and being in sections around groups of projections. Alternatively each projection may have its own tubular shield supported on the projection (Fig. 7) or separately or formed integrally (Fig. 8). When the projections are arranged rectangularly the shields may be intersecting plates between adjacent rows of projections and parallel to their axes. A solenoid-operated device controls the feed of glass to the container preferably in the form of marbles. Separate drawn fibres are gathered to form a single thread.
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