Fiber optic cable systems and kits and methods for terminating the same

Abstract

A fiber optic cable system includes a fiber optic main cable having a strength member and a plurality of optical fibers extending therein within an outer cable sheath. A flexible longitudinally extending inner housing is positioned proximate the plurality of optical fibers on a section of the main cable having-the outer cable sheath removed. At least one fiber optic drop cable has at least one optical fiber having an end portion extending outwardly from an end of the drop cable. The end portion is spliced together with an end portion of a corresponding at least one severed end portion of one of the plurality of optical fibers of the main cable to define at least one spliced together fiber portion coupling at least one of the plurality of optical fibers of the main cable to a corresponding one of the at least one fiber of the drop cable. A longitudinally extending outer protective housing extends over the section of the main cable having the outer cable sheath removed and the inner housing and the strength member. The outer protective housing has a first opening receiving the main cable and a second opening, longitudinally displaced from the first opening, receiving the main cable and at least one of the openings receiving the drop cable or cables.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating an optical fiber cable to be preterminated according to some embodiments of the present invention;

FIG. 2 is a perspective view of an inner housing of a fiber optic cable system according to some embodiments of the present invention on the optical fiber cable of FIG. 1;

FIG. 3A is a perspective view of the inner housing of FIG. 2 secured to the optical fiber cable of FIG. 1 according to some embodiments of the present invention;

FIG. 3B is a perspective view of a portion of the inner housing shown in FIG. 3A;

FIG. 4A is perspective view of an inner liner of a fiber optic cable system positioned over the inner housing of FIGS. 3A and 3B according to some embodiments of the present invention;

FIG. 4B is a cross sectioned perspective view of the arrangement of shown in FIG. 4A;

FIG. 5 is perspective view of the arrangement of FIG. 4A with environmental sealant on ends thereof according to some embodiments of the present invention;

FIG. 6 is a perspective view of a fiber optic cable system according to some embodiments of the present invention;

FIG. 7 is a flowchart illustrating operations for terminating an optical fiber according to some embodiments of the present invention;

FIG. 8 is an exploded perspective view of an cable termination arrangement according to further embodiments of the present invention on the optical fiber cable of FIG. 1;

FIGS. 9A and 9B are perspective views of the cable termination arrangement of FIG. 8 with a segment of the inner liner removed and with the apparatus secured to the optical fiber cable of FIG. 1 according to further embodiments of the present invention;

FIG. 10 is a cross sectioned perspective view of the cable termination arrangement of FIG. 8 according to further embodiments of the present invention; and

FIG. 11 is perspective view of the arrangement of FIG. 8 with environmental sealant on ends thereof according to further embodiments of the present invention.

Claims

1. A fiber optic cable system comprising: a fiber optic main cable having a strength member and a plurality of optical fibers extending therein within an outer cable sheath;a flexible longitudinally extending inner housing positioned proximate the plurality of optical fibers on a section of the main cable having the outer cable sheath removed;a fiber optic drop cable having at least one optical fiber having an end portion extending outwardly from an end of the drop cable, the end portion of the at least one optical fiber of said drop cable being spliced together with an end portion of a corresponding at least one severed end portion of one of the plurality of optical fibers of the main cable to define at least one spliced together fiber portion coupling at least one of the plurality of optical fibers of the main cable to a corresponding one of the at least one fiber of the drop cable; anda longitudinally extending outer protective housing extending over the section of the main cable having the outer cable sheath removed and the inner housing and the strength member, the outer protective housing having a first opening receiving the main cable and a second opening, longitudinally displaced from the first opening, receiving the the main-cable and wherein at least one of the first opening and the second opening receive the drop cable.

2. The fiber optic cable system of claim 1, wherein the inner housing is positioned around the plurality of optical fibers and between the plurality of optical fibers and the strength member and wherein the at least one spliced together fiber portion is positioned within the inner housing and wherein the plurality of optical fibers are positioned in a central core tube of the main cable longitudinally extending along a central axis of the main cable and wherein a length of the central core tube is removed in the section of the main cable having the outer cable sheath removed so that at least a portion of the at least one spliced together fiber portion is positioned at a position radially displaced from the central axis by a distance of no more than half an outer diameter of the central core tube.

3. The fiber optic cable system of claim 2, wherein the at least one spliced together fiber portion is located so that the at least one spliced together fiber portion is positioned in the inner housing at a position radially displaced from the central axis by a distance of no more that about half an outer diameter of the outer sheath.

4. The fiber optic cable system of claim 1, wherein the inner housing is positioned between the plurality of optical fibers and the strength member and wherein the plurality of optical fibers are positioned in a central core tube of the main cable longitudinally extending along a central axis of the main cable and wherein a length of the central core tube is removed in the section of the main cable having the outer cable sheath removed.

5. The fiber optic cable system of claim 4, further comprising a flexible longitudinally extending inner liner positioned around the inner housing and between the inner housing and the strength member, wherein the inner liner has a crush resistance in a radial direction relative to the central axis of the main cable greater than a crush resistance of the inner housing.

6. The fiber optic cable system of claim 5, wherein the strength member comprises a pair of strength members and wherein the pair of strength members is positioned proximate substantially opposing sides of the inner liner so that the fiber optic cable system is more resistant to bending about a first transverse axis extending between the pair of strength members than along a second transverse axis orthogonal to the first transverse axis.

7. The fiber optic cable system of claim 6, further comprising a plurality of protective housings at predetermined positions along the main cable and wherein the main cable with the protective housings thereon is wound around a cable spool with the second transverse axis oriented to facilitate wrapping of the main cable around the spool.

8. The fiber optic cable system of claim 6 wherein the inner liner comprises a longitudinally slit polymeric flex conduit.

9. The fiber optic cable system of claim 8, further comprising a first cutout on each end of the flex conduit that receive and position a first of the pair of strength members extending therebetween and a second cutout on each end of the flex conduit positioned substantially 180° from the first cutout that receive and position a second of the pair of strength members extending therebetween.

10. The fiber optic cable system of claim 9, wherein a greater longitudinal length of the outer sheath is removed than of the central core tube to expose a segment of the central core tube at each end of the section of the main cable having the outer cable sheath removed and wherein the cable system further comprises: a first attachment member coupling a first end of the inner housing to one of the exposed segments of the central core tube;a second attachment member coupling a second end of the inner housing to the other of the exposed segments of the central core tube and coupling the drop cable to the main cable; andan environmental sealant surrounding each of the exposed segments of the core tube, wherein the environmental sealant and the attachment members are positioned in the outer protective housing.

11. The fiber optic cable system of claim 10, wherein the drop cable further includes a buffer tube extending outwardly from the end of the drop cable with the at least one optical fiber therein and wherein the second attachment member couples the buffer tube of the drop cable to the central core tube of the main cable.

12. The fiber optic cable system of claim 10, wherein the first and second attachment members comprise tie wraps and wherein the environmental sealant comprises hot melt adhesive and wherein the outer protective housing comprises heatshrink and wherein the plurality of optical fibers of the main cable and the at least one optical fiber of the drop cable comprise ribbon cables.

13. The fiber optic cable system of claim 12, wherein the inner housing comprises: an inner wall positioned between the at least one optical fiber of the drop cable and the at least one spliced together fiber portion and uncut ones of the plurality of optical fibers of the main cable extending across the section of the main cable having the outer cable sheath removed, the inner wall having a connector member on a first longitudinally extending end thereof;a first wrap around outer wall extending from a second end of the central wall displaced from the connector member and having a mating connector member on a second end thereof coupled to the connector member to define a first chamber around the uncut ones of the plurality of optical fibers of the main cable;a second wrap around outer wall extending from the second end of the central wall and having a mating connector member on a second end thereof coupled to the connector member to define a second chamber around the at least one optical fiber of the drop cable and the at least one spliced together fiber portion; andtie-down extension members extending from at least one of the outer walls on longitudinally displaced ends of the inner housing and extending over the exposed segments of the central core tube, wherein the tie-wraps couple the extension members to the respective exposed segments of the central core tube.

14. The fiber optic cable system of claim 4, wherein the inner housing comprises: an inner wall positioned between the at least one optical fiber of the drop cable and the at least one spliced together fiber portion and uncut ones of the plurality of optical fibers of the main cable extending across the section of the main cable having the outer cable sheath removed, the central wall having a connector member on a first longitudinally extending end thereof;a first wrap around outer wall extending from a second end of the central wall displaced from the connector member and having a mating connector member on a second end thereof coupled to the connector member to define a first chamber around the uncut ones of the plurality of optical fibers of the main cable; anda second wrap around outer wall extending from the second end of the central wall and having a mating connector member on a second end thereof coupled to the connector member to define a second chamber around the at least one optical fiber of the drop cable and the at least one spliced together fiber portion.

15. The fiber optic cable system of claim 1, wherein the cable system comprises a factory preterminated optical fiber cable having a plurality of drop cables spliced to the main cable in inner housings positioned at a plurality of predetermined longitudinal positions on the cable.

16. The fiber optic cable system of claim 1, further comprising a second fiber optic drop cable having at least one optical fiber having an end portion extending outwardly from an end of the second drop cable, the end portion of the at least one optical fiber of said second drop cable being spliced together with an end portion of a corresponding at least one severed end portion of one of the plurality of optical fibers of the main cable within the inner housing to define at least one second spliced together fiber portion coupling at least one of the plurality of optical fibers of the main cable to a corresponding one of the at least one fiber of the second drop cable.

17. The fiber optic cable system of claim 1, wherein the inner housing comprises a longitudinally extending dividing wall positioned between uncut ones of the plurality of optical fibers and the at least one spliced together fiber portion.

18. The fiber optic cable system of claim 17, further comprising a flexible longitudinally extending inner liner positioned around the inner housing and between the plurality of optical fibers and the at least one spliced together fiber portion and the strength member and wherein the inner liner includes positioning surfaces therein configured to receive the inner housing.

19. The fiber optic cable system of claim 18, wherein the inner liner further comprises guide members extending laterally therefrom that are configured to receive and position the strength member extending longitudinally proximate an outer surface of the inner liner.

20. The fiber optic cable system of claim 18, wherein the inner liner includes: a longitudinally extending first segment having a connecting member thereon;a longitudinally extending second segment having a mating connecting member thereon configured to receive the connecting member of the first segment to couple the first segment and the second segment in a position extending around the inner housing, the plurality of optical fibers and the at least one spliced together fiber portion.

21. A kit for use in factory preterminating at least one optical fiber of a fiber optic drop cable to a corresponding one of a plurality of optical fibers extending within an outer cable sheath of a fiber optic main cable, the kit comprising: a flexible longitudinally extending inner housing configured to be positioned proximate the plurality of optical fibers on a section of the main cable having the outer cable sheath removed and between uncut ones of the plurality of optical fibers and at least one spliced together fiber portion coupling at least one of the plurality of optical fibers of the main cable to a corresponding one of the at least one fiber of the drop cable; anda longitudinally extending outer protective housing configured to extend over the section of the main cable having the outer cable sheath removed and the inner housing and the strength member, the outer protective housing having a first opening configured to receive the main cable and a second opening, longitudinally displaced from the first opening, configured to receive the drop cable and the main cable.

22. The kit of claim 21, wherein the inner housing is configured to be positioned around the plurality of optical fibers and between the plurality of optical fibers and the strength member of the main cable.

23. The kit of claim 21, wherein the inner housing comprises: an inner wall configured to be positioned between the at least one optical fiber of the drop cable and the at least one spliced together fiber portion and uncut ones of the plurality of optical fibers of the main cable extending across the section of the main cable having the outer cable sheath removed, the central wall having a connector member on a first longitudinally extending end thereof;a first wrap around outer wall extending from a second end of the central wall displaced from the connector member and having a mating connector member on a second end thereof configured to be coupled to the connector member to define a first chamber around the uncut ones of the plurality of optical fibers of the main cable; anda second wrap around outer wall extending from the second end of the central wall and having a mating connector member on a second end thereof configured to be coupled to the connector member to define a second chamber around the at least one optical fiber of the drop cable and the at least one spliced together fiber portion.

24. The kit of claim 21, further comprising a flexible longitudinally extending inner liner configured to be positioned around the inner housing and between the inner housing and the strength member, wherein the inner liner has a crush resistance in a radial direction relative to a central axis of the main cable greater than a crush resistance of the inner housing.

25. The kit of claim 21, wherein the inner liner comprises a longitudinally slit polymeric flex conduit and wherein the outer protective housing comprises tubular heatshrink.

26. The kit of claim 21, further comprising a first cutout on each end of the flex conduit configured to receive and position a first of a pair of strength members of the main cable extending therebetween and a second cutout on each end of the flex conduit positioned substantially 180° from the first cutout that are configured to receive and position a second of the pair of strength members extending therebetween.

27. A method of factory terminating an optical fiber cable, comprising: determining a number of longitudinally offset predetermined termination points to be provided on the optical fiber cable, wherein the number is greater than one;sliding a number of tubular outer protective housings onto the optical fiber cable over a first end of the optical fiber cable, wherein the number of tubular outer protective housings is at least equal to the number of termination points;removing the outer cable sheath- from a section of the optical fiber cable corresponding to a first of the termination points to expose a portion of a fiber protection tube of the optical fiber cable;removing a length of the exposed fiber protection tube to expose a plurality of optical fibers of the optical fiber cable;severing an exposed one of the plurality of optical fibers;splicing the severed optical fiber of the optical fiber cable to an optical fiber of another optical fiber cable to provide a splice;sliding one of the tubular outer protective housings over the section of the optical fiber cable having the outer cable sheath removed; andsecuring the outer protective housing to the optical fiber cable to provide an environmental closure around the inner housing with the optical fiber cable extending from respective longitudinally displaced ends of the outer protective housing and the another optical fiber cable extending from at least one of the ends of the outer protective housing.

28. The method of claim 27, wherein splicing the severed optical fiber is followed by: positioning the splice in a location proximate the removed length of the exposed fiber protection tube;positioning an inner housing proximate the exposed plurality of optical fibers of the optical fiber cable and the splice;securing longitudinally displaced ends of the positioned inner housing to respective un-removed exposed portions of the fiber protection tube extending from the optical fiber cable adjacent the section of the optical fiber cable having the outer cable sheath removed; andrepeating removing the outer cable sheath, removing a length of the exposed central core tube, severing an exposed one of the plurality of optical fibers, splicing the severed optical fiber, splicing the severed optical fiber, positioning the splice, positioning the inner housing, securing longitudinally displaced ends, sliding one of the tubular outer protective housings and securing the outer protective housing at additional ones of the predetermined termination points to splice additional optical fiber cables to the optical fiber cable.

29. The method of claim 28, wherein positioning the inner housing comprises positioning the inner housing around the exposed plurality of optical fibers of the optical fiber cable and the splice and between the plurality of optical fibers and the splice and an exposed strength member of the optical fiber cable.

30. The method of claim 27, wherein sliding one of the tubular outer protective housings is preceded by positioning an inner liner around the inner housing and between the inner housing and the strength member.

31. The method of claim 27, wherein the outer protective housing comprises heatshrink and wherein securing the outer protective housing comprises heating the heatshrink.