Apparatus and method used in the assembly of fibre optic cables

Apparatus for assembling a fibre optic structure of longitudinally extending constituent members upon the surface of a central strength filament, said apparatus comprising:

• a laying-up unit located in a laying-up station along a feed path for the filament for laying up said members upon the surface of the filament as it is passed through said laying-up station;
• member feeding means upstream of the laying-up unit to pass the members to the laying-up unit while providing an amount of slack in the members;
• and
• tension reducing means for the laid-up members and disposed downstream of the laying-up unit, said tension reducing means comprising an inner tubular member defining an inner passage disposed along the feed path for movement through the inner passage of the filament carrying the laid-up members, an outer tubular member defining with the inner tubular member an annular spacing surrounding the passage, and a fluid inlet port to admit fluid under pressure into the annular spacing, the two tubular members being joined to close the spacing at its end upstream of the feed path and being spaced at the downstream end of the spacing to define an annular outlet facing in the downstream direction and surrounding the inner passage for the flow of pressurized fluid from the spacing and downstream along the feedpath, the outer tubular member extending downstream beyond the inner tubular member to contain the pressurized fluid around the feed path as it flows from the spacing.