초록 ▼

An inner duct is disclosed which can fit inside a duct and extend along a length thereof for receiving communication cable, particularly a light-guide cable. The inner duct has a continuous side wall with protruding ribs on the inside and outside surfaces to maintain an effective supply of lubricant

An inner duct is disclosed which can fit inside a duct and extend along a length thereof for receiving communication cable, particularly a light-guide cable. The inner duct has a continuous side wall with protruding ribs on the inside and outside surfaces to maintain an effective supply of lubricant during the installation of the inner duct and cable in the inner duct. The ribs on the inside surface of the inner duct guide the cable during the placement operation. It is preferred to install a plurality of inner ducts into a duct during which the ribs on the inner duct interlock with one another to prevent spiraling. The ribs also facilitate the dissipation of heat due to friction and ambient sources of heat.

대표청구항 ▼

A method for installing a transmission cable in a selected length of a duct comprising the steps of: selecting a length of an inner duct which can fit inside said duct, said inner duct having a wall surface with protruding ribs extending in the direction of the length of the inner duct, installing t

A method for installing a transmission cable in a selected length of a duct comprising the steps of: selecting a length of an inner duct which can fit inside said duct, said inner duct having a wall surface with protruding ribs extending in the direction of the length of the inner duct, installing the inner duct inside the duct to extend along the length thereof, and installing a transmission cable in said inner duct.