GROOVED SPACER FOR OPTICAL CABLE

• Main Authors: IMADA EIJI, HARA MASAMI, KAMIKURA YASUHIRO
• Format: Patent
• Language: English
• Published: 05.03.1999
• Edition: 6
• Subjects: OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

PROBLEM TO BE SOLVED: To make it possible to embody an optical cable which is light, is easy to bend and has good mechanical characteristics by consisting a thermoplastic resin layer of a foamed thermoplastic resin and satisfying a specific relation between the expansion rate thereof and the min. spacings between the adjacent grooves thereof. SOLUTION: The grooved spacer 1 is provided with the thermoplastic resin layer 3 around its central tension member 2. Plural pieces of coated optical fiber-housing grooves 4 are formed at equal intervals circumferentially on the outer periphery of this thermoplastic resin layer 3. The thermoplastic resin layer 3 comprises a foamed thermoplastic resin. The expansion rate of the thermoplastic resin is desirable to be made high in order to make such optical cable easy to bend and light, but mechanical strength is insufficient if the expansion rate is made too high. The min. spacings of the adjacent grooves of the grooved spacer 1 affect the mechanical strength as well. When the expansion rate of the thermoplastic resins defined as A% and the min. spacings of the adjacent grooves are defined as t(mm), t/A>=0.02 is satisfied. As a result, the optical cable which is light, is easy to bend and has the good mechanical characteristics may be embodied.