Modified pre-ferrulized communication cable assembly and installation method
Disclosed is a modified pre-ferrulized cable assembly that facilitates installation of an optical fiber communication cable through narrow cable guides having sharp bends. The pre-ferrulized cable assembly includes a communication cable having a free, front end, a semi-finished communication connector, and a suction plug. The invention further relates to efficient methods for installing the modified pre-ferrulized cable assembly through a cable guide.
1. A modified pre-ferrulized cable assembly that facilitates installation of an optical fiber communication cable through a cable guide, the modified pre-ferrulized cable assembly having a substantially rigid portion and comprising:
a communication cable having a free, front end, said communication cable comprising at least one cable sheath coaxially surrounding an optical fiber;
a semi-finished connector in communicative contact with said optical fiber, the semi-finished connector including a connecting element that fixedly surrounds said free, front end of said communication cable, the semi-finished connector at least partly defining a substantially rigid portion of the pre-ferrulized cable assembly; and
a plug assembly that is secured to the communication cable and/or the semi-finished connector, said plug assembly comprising a suction plug;
wherein, after said plug assembly is removed, said connecting element can be mechanically connected to a complementary connector to form a completed communication connector;
wherein said pre-ferrulized cable assembly is capable of passing through a cable guide bend defining a bend radius that is less than the predicted minimum bend radius R b according to the following equation:
R
b
=
(
1
2
l
)
2
+
(
D
-
d
)
2
2
(
D
-
d
)
wherein,
D is the inner diameter of the cable guide;
l is the maximum length of the substantially rigid portion of said pre-ferrulized cable assembly; and
d is the maximum diameter of the substantially rigid portion of said pre-ferrulized cable assembly.
2. A modified pre-ferrulized cable assembly according to claim 1 , wherein said pre-ferrulized cable assembly is capable of passing through a cable guide bend defining a bend radius that is less than about 75 percent of the predicted minimum bend radius R b according to the following equation:
R
b
=
(
1
2
l
)
2
+
(
D
-
d
)
2
2
(
D
-
d
)
wherein,
D is the inner diameter of the cable guide;
l is the maximum length of the substantially rigid portion of said pre-ferrulized cable assembly; and
d is the maximum diameter of the substantially rigid portion of said pre-ferrulized cable assembly.
3. A modified pre-ferrulized cable assembly according to claim 1 , wherein said pre-ferrulized cable assembly is capable of passing through a cable guide bend defining a bend radius that is less than about 50 percent of the predicted minimum bend radius R b according to the following equation:
R
b
=
(
1
2
l
)
2
+
(
D
-
d
)
2
2
(
D
-
d
)
wherein,
D is the inner diameter of the cable guide;
l is the maximum length of the substantially rigid portion of said pre-ferrulized cable assembly; and
d is the maximum diameter of the substantially rigid portion of said pre-ferrulized cable assembly.
4. A modified pre-ferrulized cable assembly according to claim 1 , wherein:
said communication cable comprises at least one cable sheath coaxially surrounding a plurality of optical fibers; and
said semi-finished connector is in communicative contact with at least one of said optical fibers.
5. A modified pre-ferrulized cable assembly according to claim 4 , wherein said semi-finished connector is in communicative contact with each of said optical fibers.
6. A modified pre-ferrulized cable assembly according to claim 1 , wherein at least one said cable sheath comprises a strain-relieving element.
7. A modified pre-ferrulized cable assembly according to claim 1 , wherein said semi-finished connector further comprises a spring element, said spring element positioned around said optical fiber between said connecting element and said at least one cable sheath.
8. A modified pre-ferrulized cable assembly according to claim 7 , wherein said spring element is retained by said connecting element and a retaining sleeve positioned around said optical fiber.
9. A modified pre-ferrulized cable assembly according to claim 1 , wherein said connecting element comprises at least one recess in its circumferential surface.
10. A modified pre-ferrulized cable assembly according to claim 9 , wherein said recess is a circular recess formed in the circumferential surface of said connecting element.
11. A modified pre-ferrulized cable assembly according to claim 1 , wherein said plug assembly further comprises a removable protective element that is positioned between said free, front end of said communication cable and said suction plug to thereby protect said semi-finished connector.
12. A modified pre-ferrulized cable assembly according to claim 1 , wherein the maximum diameter of the substantially rigid portion of said pre-ferrulized cable assembly is between about 60 and 95 percent of the inner diameter of said cable guide.
13. A modified pre-ferrulized cable assembly according to claim 1 , wherein the maximum diameter of the substantially rigid portion of said pre-ferrulized cable assembly is between about 70 and 85 percent of the inner diameter of said cable guide.
14. A modified pre-ferrulized cable assembly according to claim 1 , wherein the maximum diameter of said pre-ferrulized cable assembly is less than about 200 percent of the diameter of said communication cable.
15. A modified pre-ferrulized cable assembly according to claim 1 , wherein the maximum diameter of said pre-ferrulized cable assembly is less than about 150 percent of the diameter of said communication cable.
16. A modified pre-ferrulized cable assembly according to claim 1 , wherein the maximum diameter of said pre-ferrulized cable assembly is less than about 120 percent of the diameter of said communication cable.
17. A modified pre-ferrulized cable assembly according to claim 1 , wherein the diameter of the substantially rigid portion of said pre-ferrulized cable assembly is less than the diameter of said communication cable.
18. A modified pre-ferrulized cable assembly according to claim 1 , wherein the length of the substantially rigid portion of said pre-ferrulized cable assembly is less than about ten times its maximum diameter.
19. A modified pre-ferrulized cable assembly according to claim 1 , wherein the length of the substantially rigid portion of said pre-ferrulized cable assembly is less than about eight times its maximum diameter.
20. A modified pre-ferrulized cable assembly according to claim 1 , wherein the length of the substantially rigid portion of said pre-ferrulized cable assembly is less than about six times its maximum diameter.
21. A method of installing a modified pre-ferrulized cable assembly through a cable guide, comprising:
providing a semi-finished cable assembly comprising (i) an optical fiber communication cable having a free, front end and (ii) a semi-finished connector that is secured to the optical fiber communication cable, the semi-finished connector including a connecting element that fixedly surrounds the free, front end of the communication cable;
securing a plug assembly to the semi-finished cable assembly to form a modified pre-ferrulized cable assembly;
guiding the modified pre-ferrulized cable assembly through the cable guide from a starting point to an end point, the plug assembly causing localized deformation in the cable guide to facilitate movement of the semi-finished cable assembly through the cable guide;
thereafter, detaching the plug assembly from the modified pre-ferrulized cable assembly; and
mechanically securing a complementary connector to the connecting element thereby completing the communication connector.
22. A method of installing a modified pre-ferrulized cable assembly according to claim 21 , wherein the plug assembly comprises a suction plug for guiding the pre-ferrulized cable assembly through the cable guide.
23. A method of installing a modified pre-ferrulized cable assembly according to claim 22 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises the suction plug causing local deformation at a bend in the cable guide to facilitate movement of the semi-finished cable assembly through the cable guide.
24. A method of installing a modified pre-ferrulized cable assembly according to claim 22 , wherein the plug assembly further comprises a protective element for protecting the semi-finished connector.
25. A method of installing a modified pre-ferrulized cable assembly according to claim 21 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises blowing the modified pre-ferrulized cable assembly through the cable guide.
26. A method of installing a modified pre-ferrulized cable assembly according to claim 21 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises the plug assembly leading the pre-ferrulized cable assembly through a section of the cable guide that has (i) a substantially constant inner diameter of 3 millimeters or less and (ii) a bend radius of less than 75 millimeters.
27. A method of installing a modified pre-ferrulized cable assembly according to claim 26 , wherein the plug assembly leads the pre-ferrulized cable assembly through a section of the cable guide having an outside diameter of about 4 millimeters or more.
28. A method of installing a modified pre-ferrulized cable assembly according to claim 21 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises the plug assembly leading the pre-ferrulized cable assembly through a section of the cable guide that has (i) an inside diameter of about 3 millimeters or less and (ii) a bend radius of between about 35 millimeters and 55 millimeters.
29. A method of installing a modified pre-ferrulized cable assembly according to claim 21 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises the plug assembly leading the pre-ferrulized cable assembly through a section of the cable guide that has (i) an inside diameter of about 3 millimeters or less and (ii) a bend radius of less than about 35 millimeters.
30. A method of installing a modified pre-ferrulized cable assembly according to claim 21 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises the plug assembly leading the pre-ferrulized cable assembly through a section of the cable guide that has (i) a substantially constant inner diameter of about 3 millimeters or less and a substantially constant outer diameter of about 4 millimeters or more and (ii) a bend radius of between about 35 millimeters and 65 millimeters.
31. A method of installing a modified pre-ferrulized cable assembly according to claim 21 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises the plug assembly leading the pre-ferrulized cable assembly through a section of the cable guide that has (i) a substantially constant inner diameter of about 3.5 millimeters or less and (ii) a bend radius of less than 50 millimeters.
32. A method of installing a modified pre-ferrulized cable assembly according to claim 31 , wherein the plug assembly leads the pre-ferrulized cable assembly through a section of the cable guide having an outside diameter of about 5 millimeters or more.
33. A method of installing a modified pre-ferrulized cable assembly according to claim 21 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises the plug assembly leading the pre-ferrulized cable assembly through a section of the cable guide that has (i) a substantially constant inner diameter of about 4 millimeters or less and (ii) a bend radius of less than 35 millimeters.
34. A method of installing a modified pre-ferrulized cable assembly according to claim 33 , wherein the plug assembly leads the pre-ferrulized cable assembly through a section of the cable guide having an outside diameter of about 5 millimeters or more.
35. A method of installing a modified pre-ferrulized cable assembly according to claim 21 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises blowing the pre-ferrulized cable assembly through a cable guide bend that defines a bend radius that is less than the predicted minimum bend radius R b according to the following equation:
R
b
=
(
1
2
l
)
2
+
(
D
-
d
)
2
2
(
D
-
d
)
wherein,
D is the inner diameter of the cable guide;
l is the maximum length of the substantially rigid portion of the pre-ferrulized cable assembly; and
d is the maximum diameter of the substantially rigid portion of the pre-ferrulized cable assembly.
36. A method of installing a modified pre-ferrulized cable assembly through a cable guide, comprising:
providing a semi-finished cable assembly comprising (i) an optical fiber communication cable having a free, front end and (ii) a semi-finished connector that is secured to the optical fiber communication cable, the semi-finished connector including a connecting element that fixedly surrounds the free, front end of the communication cable;
securing a plug assembly to the semi-finished cable assembly to form a modified pre-ferrulized cable assembly;
guiding the modified pre-ferrulized cable assembly through the cable guide from a starting point to an end point, comprising:
blowing the pre-ferrulized cable assembly through a cable guide bend that defines a bend radius that is less than the predicted minimum bend radius R b according to the following equation:
R
b
=
(
1
2
l
)
2
+
(
D
-
d
)
2
2
(
D
-
d
)
wherein,
D is the inner diameter of the cable guide;
1 is the maximum length of the substantially rigid portion of the pre-ferrulized cable assembly; and
d is the maximum diameter of the substantially rigid portion of the pre-ferrulized cable assembly;
thereafter, detaching the plug assembly from the modified pre-ferrulized cable assembly; and
mechanically securing a complementary connector to the connecting element thereby completing the communication connector.
37. A method of installing a modified pre-ferrulized cable assembly according to claim 36 , wherein the plug assembly comprises a suction plug for guiding the pre-ferrulized cable assembly through the cable guide.
38. A method of installing a modified pre-ferrulized cable assembly according to claim 37 , wherein the plug assembly further comprises a protective element for protecting the semi-finished connector.
39. A method of installing a modified pre-ferrulized cable assembly according to claim 36 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises the plug assembly leading the pre-ferrulized cable assembly through a section of the cable guide that has (i) a substantially constant inner diameter of 3 millimeters or less and (ii) a bend radius of less than 75 millimeters.
40. A method of installing a modified pre-ferrulized cable assembly according to claim 36 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises the plug assembly leading the pre-ferrulized cable assembly through a section of the cable guide that has (i) a substantially constant inner diameter of about 3.5 millimeters or less and (ii) a bend radius of less than 50 millimeters.
41. A method of installing a modified pre-ferrulized cable assembly according to claim 36 , wherein the step of guiding the modified pre-ferrulized cable assembly through the cable guide comprises the plug assembly leading the pre-ferrulized cable assembly through a section of the cable guide that has (i) a substantially constant inner diameter of about 4 millimeters or less and (ii) a bend radius of less than 35 millimeters.
42. A modified pre-ferrulized cable assembly according to claim 1 , wherein said plug assembly is capable of causing local deformation in the cable guide to facilitate movement of the modified pre-ferrulized cable assembly through the cable guide.