PRODUCTION OF LONG SPAN NON-METALLIC OPTICAL CABLE

摘要

PURPOSE:To provide freely and exactly the quantity of sagging to a cable by producing the self-supporting cable opened with windows to provide sagging while rotating alternately a nipple for extrusion coating, die, and window opening key to the right and left. CONSTITUTION:The die 12 which is rotationally driven back and forth is provided to the die body 8. A suspension wire insertion hole 4 is provided at the center of the die 12. A cable core insertion hole 6 is provided alongside the same and a neck part forming hole 5 is provided between the same. A freely vertically movable forming key 7 for forming air windows 13 is provided to the neck part. A rod 10 of, for example, FRP which is used as the core wire of the suspension wire is inserted into the hole 4 and the optical fiber cable 11 is inserted into the hole 6. A molten coating material 9 is forced from the inside of the die 12 into the hole 4, the hole 5 and the hole 5 along with such insertion, then the cable is molded and extruded forward in the tumbler shape from the die 12. The tip of the key 7 plunges into the neck part when the key 7 ascends from the solid line position shown in the figure to the chain line position. The window 13 is thus formed.