Optical fibre introduction by blowing into tubular passageway - employs viscous drag on surface of fibre in region downstream from pressure gradient generated by venturi

摘要

The blowing head (3) comprises an elongated tube (4) whose downstream end communicates with the passageway (2) into which an optical fibre member (1) is to be blown. A source of gas (pref. compressed air) is connected to a side arm (5) upstream from a venturi constriction (6) into which a hypodermic tube (7) extends with adjustment by a collet chuck (8). A pair of downstream lateral vent tubes (9) discharge adjustable amts. of air to atmos. through control valves (10) and silencers (11). The flow of air into the hypodermic tube (7) assists movement of the fibre (1) through it into the passageway (2).