Abstract: A fibre optic cable (500, 700, 1420) comprises one or more fibre units (502, 1302). Each fibre unit comprises two or more optical fibres (506, 1306) embedded in a solid resin material (520, 1320) to form a coated fibre bundle and an extruded polymer sheath (524, 1324). The sheath (524, 1324) of each fibre unit is primarily polybutylene terephthalate (PBT), with a friction reducing additive such as polydimethylsiloxane (PDMS). The additive may be polythene based and/or polyacrylate based. The fibre unit may be applied in a pullback cable (500, 800, 1100), as a cable for pulling or pushing or as a blown fibre cable (502, 1302).

Abstract: A fibre optic cable (500, 700) comprises retractable fibre units (502) extending in parallel with one another within an extruded polymer tube (504). The fibre units are free to slide in the tube such that a selected fibre unit (702a) can be accessed and re-directed by forming an opening in a wall of the tube (504) and withdrawing the selected fibre unit through the opening (710). Each fibre unit comprises two or more optical fibres (506) embedded in a solid resin material (520) to form a coated fibre bundle and an extruded polymer sheath (524). The fibre optic cable is manufactured by feeding the fibre units through an extrusion head (602) by which the extruded tube (504) is formed. The sheath (524) of each fibre unit is primarily polyethylene. A lining (510) of the extruded polymer tube is formed by polymer other than polyethylene, for example polypropylene.

Abstract: A slip friction drive for powered roller conveyor apparatus which minimizes coupling of forces between the driving engagement and the bearing surfaces and additionally provides an adjusting means for compensating for the varying frictional forces caused by changing loads.

Abstract: A roller of the slip-type is comprised of a sleeve with an insert press fitted therein. The other end of the insert houses a bearing assembly, the inner and outer race of which are respectively keyed to a stationary support axle and to the insert. A driven element is loosely mounted about the insert but is pressed against the insert by a belt under tension which also engages one or more driven elements of adjacent rollers. The driven element is driven by an endless driving devices. When a counter-torque is experienced by the roller due to an impediment which is greater than the driving torque, slippage will occur between the driven element and the insert, and the article being carried by the conveyor will come to rest.