Information
-
Patent Grant
-
6297454
-
Patent Number
6,297,454
-
Date Filed
Thursday, December 2, 199924 years ago
-
Date Issued
Tuesday, October 2, 200122 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Reichard; Dean A.
- Mayo, III; William H.
Agents
- Conte; Robert F. I.
- Lee, Mann, Smith, McWilliams, Sweeney & Ohlson
-
CPC
-
US Classifications
Field of Search
US
- 174 110 R
- 174 113 R
- 174 113 C
- 174 120 R
- 174 113 AS
-
International Classifications
-
Abstract
A cable separator spline and a cable containing the cable separator spline in its core. The spline extends longitudinally and has a plurality of spaced longitudinally extending open pockets in which cables, such as twisted pair cables, can be placed and form part of the core. A cross-section of the spline has a major axis and a minor axis with the major axis being longer than the minor axis. At least one and preferably at least two pockets are on the major axis, and at least one and preferably at least two pockets are on the minor axis. The core containing the twisted pair cables in the pockets can of course be shielded and jacketed, just jacketed or any other desired cable construction that would benefit from the use of my elongated separator spline.
Description
FIELD OF THE INVENTION
The present invention relates to a separator filler or spline. More particularly the present invention relates to the separator filler or spline having four pockets with each pocket having a cross-sectional area that is less than the envelope area of a pair of cables adapted to be placed in each pocket.
BACKGROUND OF THE INVENTION
The most popular separator fillers or splines are generally based on a circular cross-section wherein each pocket generally has a cross-sectional area that is greater than the cross-sectional envelope area of the twisted pair cable that is to be placed in the pocket. This type of spline generally has less flexibility and undesirable to skew degradation.
SUMMARY OF THE INVENTION
The oval envelope provided by my spline has an acceptable NEXT performance and good flexibility. Therefore, it is an object of the present invention to provide a cable separator filler or spline having a plurality and preferably four opened pockets for separating a plurality of cable pairs, preferably one cable pair for each pocket. Preferably when there are an even number of pockets, the pockets are diametrically opposite each other. When there are four pockets, the first and second pockets are diametrically opposite each other and third and fourth pockets are diametrically opposite each other. In a cross-sectional plane of the spline the diametric distance between the ends of the first and second pockets is greater than the diametric distance of the ends of the group of the third and fourth pockets to provide an oval envelope for the spline. All of the pockets have a cross-sectional area that is less than the envelope cross-sectional area of the cable pair that is to be placed in the respective pockets. The longitudinal axis of each of the pockets are all substantially parallel to each other.
A cable manufactured using the spline of my invention generally uses an oval envelope spline having four pockets and has a twisted pair cable in each pocket. The long lay twisted pair cables are both preferably in the pockets on the major axis of the oval envelope. The short lay twisted pair cables are both in the pockets on the minor axis of the oval envelope. In this embodiment the core components are comprised of the elongated separator spline and the four twisted pair cables. The core can of course be shielded and jacketed, just jacketed or any other desired cable construction that would benefit from the use of my elongated separator spline.
With my elongated separator spline long and short lay twisted pairs can be ideally placed for maximum electrical advantages. Short lay pairs, which have the best flexibility can be placed across the minor axis of the separator spline. Short lays typically have improved NEXT and the close proximity to one another does little to worsen NEXT. The long lay pairs can be placed across the major axis where bending strain is minimized. This overall cable design will bend across the minor axis based on the fact that the “column” will collapse across its minimum integral bending moment axis. The use of my elongated separator spline also improves skew over a similar round design because two unique cabling lay factors are in practice when the twisted pairs are cabled (minor and major axis). This helps compensate for the pair lengths between the long and short lay pairs equalizing the final conductor lengths which also tends to improve attenuation delta from the minimum lay pair to the maximum lay pair. My spline may be “metalized”, or coated with any form of metallic material that will preserve its exterior shape, and substantially improve NEXT while still enhancing the attenuation delta and skew of pairs.
Generally alien NEXT is minimized since the cables “oval” will provide air spacing between parallel cables of any other type. Also there are economies in my spline over the generally used cylindrical splines in that less filler material generally is used in my elongated separator spline than in a round design for equal performance.
The present invention and the advantages thereof will become more apparent upon consideration of the following detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a perspective view of the elongated separator spline of my invention.
FIG. 2
is a cross-sectional view taken along lines
2
—
2
of FIG.
1
.
FIG. 3
is the same as
FIG. 2
except having a shaded portion to define a cross-sectional area.
FIG. 4
is a cross-section of a twisted pair cable to be used with the spline of FIG.
1
.
FIG. 5
is perspective view of a cable utilizing my elongated separator spline.
FIG. 6
is a cross-section view taken along lines
6
—
6
of FIG.
5
.
FIG. 7
is a perspective view of another cable utilizing my elongated separator spline.
FIG. 8
is a perspective view of still another cable utilizing my elongated separator spline.
FIG. 9
is a perspective view of a further cable utilizing my elongated separator spline.
DETAILED DESCRIPTION
The following description taken in conjunction with the drawings will further explain the inventive features of my elongated separator spline and cables utilizing my elongated separator spline.
Referring to
FIGS. 1 and 2
, my elongated separator spline
20
has along its cross-sectional plane a major axis
21
and a minor axis
22
. In the preferred embodiment, the minor axis
22
is perpendicular to the major axis
21
. The preferred elongated separator spline
20
is shown with four cable pockets
23
,
24
,
26
, and
27
. Other oval configurations could have more all less pockets. The pockets
23
and
24
are on the major axis
21
and pockets
27
and
26
are on the minor axis
22
. In a preferred embodiment, pockets
23
and
24
have the same cross-sectional area as each other and pockets
26
and
27
have the same cross-sectional area as each other. If desired, they can all have the same cross-sectional area. The cross-sectional area of the pockets as shown in FIG.
3
. These are indicated by the shaded areas
28
and
29
.
FIG. 4
illustrates a cross-section of a twisted pair cable
30
having a pair of conductors
35
with appropriate insulation
35
(
a
). The cable
30
has a circular envelope
31
. The cross-sectional area of the twisted pair circular envelope
31
is greater than the cross-sectional area of any of the pockets.
Each of the pockets
23
and
24
have a depth
32
and each of the pockets
26
and
27
have a depth
33
. The depths
32
and
33
of the pockets is less than the diameter
34
of the twisted pair envelope
31
. The cross-sectional depth
32
of the pockets
23
and
24
is less than the cross-sectional depth
33
of the pockets
26
and
27
. In a preferred embodiment, each of the cross-sectional areas
28
and
29
is 25% to 75% of the cross-sectional area of the envelope
31
. The preferred elongated separator spline
20
has four longitudinally extending pockets
23
,
24
,
26
and
27
of two different sizes. However, if it is desired, the sizes of the pocket can all be different depending upon the size of the cables that are to be placed in the pockets. The size of the pockets will scale up or down based on the size of the cable, i.e.,
30
(
FIG. 4
) to be placed in the pocket. If desired, the pockets may even have a depth which is greater than the diameter of the cable pair envelope. The present embodiment's major axis
21
, when measured from the inside bases of the pockets
23
and
24
, has a length
36
of 0.050 in. to about 0.100 in. The minor axis, when measured from the inside bases of the pockets
26
and
27
, has a length
37
of about 0.010 in. to about 0.030 in. The preferred material for the elongated separator spline is any suitable solid or foamed polymer or copolymer depending on the needs of the user for crush resistance, breaking strength, gel fillings, safety, and the need for flame and smoke resistance. In many applications the material will be a polyethylene.
Referring to
FIGS. 5 and 6
, there is shown a cable
40
, having as its core
44
my elongated separator spline
20
with major axis pockets
23
and
24
each containing a twisted pair cable
42
having a long lay of about 0.5 in. to about 1.5 in. and with minor axis pockets
26
and
27
each containing a twisted pair cable
41
having a short lay of about 0.25 in. to about 0.75 in. The core which contains the elongated separator spline
20
and the cables
41
and
42
in the pockets as shown in
FIGS. 5 and 6
, is surrounded by a jacket
43
which was extruded thereover. The jacket
43
can be any suitable jacket material normally utilized such as anyone of the following which also may be foamed on non-foamed i.e. polyvinyl chloride, fluorinated polymers, polyethylene, the flame retardant compositions, etc. The twisted pair cables
41
and
42
are the same construction as the twisted pair cable
30
.
Referring to
FIG. 7
there is shown a cable
50
having the same construction as the cable
40
except it has shield
51
wrapped around the core
44
. The shield
51
may be any suitable shield such as an aluminum tape, BELDFOIL, DUOFOIL, or any suitable metal tape. The shield
51
is generally laterally wrapped around the core
44
and then the jacket
43
is extruded around the shield. Although the shield is shown as a lateral wrapped tape, it can be a helically wound tape. A drain wire (not shown ) can be inserted into the cable
50
if desired.
Referring to
FIG. 8
, there is shown a cable
60
using a drain wire
61
. The cable
60
has the same construction as the cable
50
except in this embodiment of the drain wire
61
is helically wrapped around the lateral shield
51
for the dual purpose of being a drain wire and to hold the lateral shield
51
in place. The jacket
43
is then extruded over the shield
51
and drain wire
61
.
Referring to
FIG. 9
, there is shown still another cable
70
having the same construction as the cable
50
except it uses a drain wire
71
having a gentle wrap around the lateral shield
51
. The jacket
43
is then extruded over the shield
51
and drain wire
71
.
The drain wires
61
and
71
are generally made with tinned copper, tinned aluminum, etc.
The size of the twisted pair cables
41
and
42
are generally about 24 AWG. to about 22 AWG.
The conductors
35
for the twisted pair cables are generally copper, tinned copper, or an appropriate bronze and these are generally insulated with a foamed on non-foamed insulation
35
(
a
) of polyethylene, polypropylene, fluorinated ethylene propylene, tetrafluoroethylene, polyvinyl chloride, etc.
Although I have described my elongated spline as having four pockets, the spline may have more or less pockets.
It will, of course, be appreciated that the embodiments which have just been described have been given by way of illustration, and the invention is not limited to the precise embodiments described herein. Various changes and modifications may be effected by one skilled in the art at without departing from the scope or spirit of the invention as defined in the appended claims.
Claims
- 1. A communication cable separator spline comprising:a longitudinally extending spline having a plurality of spaced longitudinally extending open pockets, a cross-section of said spline having a major axis and a minor axis, at least one pocket being on the major axis, at least one pocket being on the minor axis, and each of said pockets have a cross-sectional area which is 75% or less than a cross-sectional area of a circular envelope of an insulated cable to be placed in said pockets.
- 2. The spline of claim 1 wherein,said major axis is substantially perpendicular to said minor axis, and each of said pockets longitudinally extending substantially parallel to each other.
- 3. The spline of claim 1 wherein,said spline has first, second, third, and fourth spaced longitudinally extending open pockets, a cross-section of said spline having a major axis and a minor axis, said first and second pockets having substantially the same cross-sectional area, and said third and fourth pockets having substantially the same cross-sectional area.
- 4. The spline of claim 3 wherein,said major axis is substantially perpendicular to said minor axis, said third and fourth pockets having substantially the same cross-sectional area, and said first, second, third, and fourth pockets longitudinally extending substantially parallel to each other.
- 5. The spline of claim 4, whereinsaid first and second pockets having a depth greater than a depth of said third and fourth pockets, and each of said pockets have a cross-sectional area of about 25% to 75% the cross-sectional area of the circular envelope of the cable to be placed in said pockets.
- 6. A communication cable comprising:a cable core surrounded by a jacket, said cable core having a longitudinally extending spline having first, second, third, and fourth spaced longitudinally extending open pockets for separating four twisted pair cables, a cross-section of said spline having a major axis and a minor axis, said major axis being substantially perpendicular to said minor axis, said first and second pockets been diametrically spaced from each other and being on the major axis, a first twisted pair cable having a pair of conductors with each conductor having insulation thereon and having a long lay and being in each of said first and second pockets, said third and fourth pockets been diametrically spaced from each other and being on the minor axis, a second twisted pair cable having a pair of conductors with each conductor having insulation thereon and having a short lay and being in each of said third and fourth pockets, said first and second pockets having substantially the same cross-sectional area, said third and fourth pockets having substantially the same cross-sectional area, each of said first, second, third, and fourth pockets longitudinally extending substantially parallel to each other, said first and second pockets having a depth greater than a depth of said third and fourth pockets, and each of said first, second, third, and fourth pockets having a cross-sectional area which is 25% to 75% of the cross-sectional area of a circular envelope of the twisted pair cable in said pockets.
- 7. A communication cable comprising:a cable core surrounding by a jacket, said cable core having a longitudinally extending spline having a plurality of spaced longitudinally extending open pockets, a cross section of said spline having a major axis and a minor axis, at least one pocket being on the major axis, at least one pocket being on the minor axis, and at least one insulated cable in at least two of said pockets wherein a ratio of the length of the major axis to the length of the minor axis is from 0.100:0.010 to 0.050:0.030.
- 8. The communication cable of claim 7 wherein,said major axis is substantially perpendicular to said minor axis, and each of said pockets longitudinally extending substantially parallel to each other.
- 9. The communication cable of claim 8 wherein,each of said pockets have a cross-sectional area which is 75% or less than a cross-sectional area of a circular envelope of the cable in said pocket.
- 10. The communication cable of claim 9, whereina shield surrounds said core and said jacket surrounds the shielded core.
- 11. The communication cable of claim 8 wherein,said spline has first, second, third, and fourth spaced longitudinally extending open pockets, a cross-section of said spline having a major axis and a minor axis, said first and second pockets having substantially the same cross-sectional area, and said third and fourth pockets having substantially the same cross-sectional area.
- 12. The communication cable of claim 11, whereina shield surrounds said core and said jacket surrounds the shielded core.
- 13. The communication cable of claim 11 wherein,said major axis is substantially perpendicular to said minor axis, said third and fourth pockets having substantially the same cross-sectional area, said first, second, third, and fourth pockets longitudinally extending substantially parallel to each other, a twisted pair cable having a pair of conductors with each conductor having insulation thereon and having a cross-sectional area of a circular envelope and being in each of said pockets, and each of said pockets having a cross-sectional area which is 75% or less than the cross-sectional area of the circular envelope of the twisted pair cable in said pockets.
- 14. The communication cable of claim 13, wherein a ratio of the length of the major axis to the length of the minor axis is from 0.100:0.010 to 0.050:0.030.
- 15. The communication cable of claim 13, whereinsaid first and second pockets having a depth greater than a depth of said third and fourth pockets, and each of said pockets have a cross-sectional area of about 25% to 75% the cross-sectional area of the circular envelope of the cable in said pockets.
- 16. The communication cable of claim 15, wherein a ratio of the length of the major axis to the length of the minor axis is from 0.100:0.010 to 0.050:0.030.
- 17. The communication cable of claim 15, whereina shield surrounds said core and said jacket surrounds the shielded core.
- 18. The communication cable of claim 17, wherein a ratio of the length of the major axis to the length of the minor axis is from 0.100:0.010 to 0.050:0.030.
- 19. A communication cable separator spline comprising:a longitudinally extending spline having a plurality of spaced longitudinally extending open pockets, a cross-section of said spline having a major axis having a length and a minor axis having a length, a ratio of the length of the major axis to the length of the minor axis is from 0.100:0.010 to 0.050:0.030, at least one pocket being on the major axis, and at least one pocket being on the minor axis.
- 20. The spline of claim 19 wherein,said major axis is substantially perpendicular to said minor axis, each of said pockets longitudinally extending substantially parallel to each other, and each of said pockets have a cross-sectional area which is 75% or less than a cross-sectional area of a circular envelope of a cable to be placed in said pockets.
- 21. The spline of claim 20, whereinsaid first and second pockets having a depth greater than a depth of said third and fourth pockets, and each of said pockets have a cross-sectional area of about 25% to 75% the cross-sectional area of the circular envelope of the cable to be placed in said pockets.
- 22. The spline of claim 19 wherein,said spline has first, second, third, and fourth spaced longitudinally extending open pockets, a cross-section of said spline having a major axis and a minor axis, said first and second pockets having substantially the same cross-sectional area, and said third and fourth pockets having substantially the same cross-sectional area.
US Referenced Citations (7)
Foreign Referenced Citations (1)
Number |
Date |
Country |
404332406A |
Nov 1992 |
JP |