Title:
OPTICAL CABLE
Document Type and Number:
Japanese Patent JPH01270016
Kind Code:
A
Abstract:
PURPOSE:To suppress the strain of optical fibers generated by cable bending to a small level by providing spiral grooves to the respective outside circumferences of the fibers of the optical fiber units doubled and twisted around a central tensile body, housing plural tape-like coated fiber therein and satisfying specific conditions. CONSTITUTION:All the grooved fiber bodies 2 of the units 10 having the central tensile body 1 in the center of the units have five spiral grooves on the outside circumferences and the optical coated fiber tapes 3 are housed in the respective grooves. The equiv. coefft. of elasticity in the longitudinal direction of the grooved fibers 2 with the constitution constituting in winding an top winding tape 5 on the outside circumference of the assembly formed by doubling and twisting 5 pieces of these units 10 on the outside circumference of the central tensile body 7 and armoring a sheath 6 on the outside circumference is designated as E and the sectional area thereof as A and these are so specified as the attain EA>=6.0X10<4>kg. The strain generated in the optical fibers by cable bending is thereby suppressed to the small level and the transmission characteristic and mechanical characteristics of the optical cable are improved. Particularly the long-term reliability of the optical fiber strength is assured.
Inventors:
NISHIMURA AKIRA
FUCHIGAMI KENYA
FUCHIGAMI KENYA
Application Number:
JP9960188A
Publication Date:
October 27, 1989
Filing Date:
April 22, 1988
Export Citation:
Assignee:
SUMITOMO ELECTRIC INDUSTRIES
NIPPON TELEGRAPH & TELEPHONE
NIPPON TELEGRAPH & TELEPHONE
International Classes:
G02B6/44; (IPC1-7): G02B6/44
Attorney, Agent or Firm:
Kugoro Tamamushi