| 摘要 |
PURPOSE:To reduce the force of friction for leading-out and leading-in of an optical fiber cable to extend the limit section length by allowing a magnetic attraction to act upon a tension member by a magnet, which is arranged above a protective pipe, to give buoyancy to the optical fiber cable. CONSTITUTION:Balance keeping devices 6 which arrange magnets 5 stably just above a protective pipe 3 of an optical fiber composite overhead earth wire 1 are used to arrange a row of magnets throughout the span of the optical fiber composite overhead earth wire 1 between supporting towers, and an already provided optical fiber cable 4 and a fresh optical fiber cable 12 are led out from and into the protective pipe 3 respectively simultaneously; and since tension member made of magnetic materials of the optical fiber cable 4 or 12 are attracted upward vertically by the magnetic force of each magnet, the optical fiber cable 4 or 12 is run and moved in the protective pipe 3 while receiving magnetic buoyancy to come up from the lower part of the inside peripheral face of the protective pipe 3.
|
