Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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The present invention relates generally to electrical
connectors and pertain~, more ~peciically, to an electrical
connector for providing a connection, in the field, be$ween
high voltage shielded electrical cables.
S In recent years concern for maintaining the natural ;~
environment has caused electric utility companies to use
underground installations instead of above ground high ten-
sion wires for power distribution. To facilitate the con-
struction and in~tallation of such underground power di~tri-
bution systems it often becomes necessary to interconnect,
;~ in the field, the high voltage shielded electrical cables
used in these installations. Various types of connectors
have been developed for use in such systems, each attempting ~;~
to reduce the number of components and the time required to ~;~
make a sati~factory connection.
One su~h connector is described in U.S. Patent No.
3,656,0 Rand inaludes an elastomeric housing slidably fitted
over the joined ends of a pair of high volta~e cables. This
connector further includes a pair of so-called adaptor tubes
or~ sleeves positioned resPectively over the insulating ~acket
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on each cable and received within the opposed end positions
~of the housing. The adaptor sleeves are used to accommodate ;
varying insulation diameters thus permitting the connect~r
to be used with varying sizefl cables utilizing a minimum
~25 number of component connector parts. The connector fuxther
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includes a pair of rings affixed to the lnsulating jacket of
the cable at the terminus of the insulating ~acket fore re-
straining the adaptor sleeves agflinst slidable movement towa~d
~` the cable ends when the elastomeric housing is s]idably fitted
thereover, and further includes a separate spring member in
engagement between the crimp barrel joining the cable ends
and the interior of the elastomeric housing for the purpose
of conveying heat away from the crimp barrel into and through
the elastomeric housing.
In an attempt to still further reduce the number of
parts in such connectors~ it has been proposed to threadedly
mount the restraining rings on or near the opposed ends of
the crimp barrel and utilize such rings for conveying heat
away from the crimp barrel. An example of this connector
arrangement is described in United States Patent No. 3,691~ 291
(Ta;) issued September 12~ 1972. However~ even with the latter
construction it has been found that when the barrel is joined ~ ;
to the two cable cores as by compression crimping5 for
example, it is possible to distort the screw threads on the
ends of the barrel sufficient to prevent complete displace~
ment of the threadedly mounted rings and produce a gap be-
tween the rings and the termini of the adaptor sleeves.
This~ in turn, permits undesirable movement of the adaptor
sleeves toward the cable core termini.
In still another known connector arrangement as
described for example, in United States Patent No. 3,485,935
(Kreager) issued December 23~ 1969~ a pair of separate spring
packets are disposed respectively on the cable cores be~ -
tween th~ insulating jackets thereof and the crimp barrel
joining the cable cores and which packets might conceivably
convey heat away from the jlmcture of the cable cores to
and through the connector housing. However,
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3uch ability to transfer haat is limited by the ~pringy
nature of the packet and in any event, such means would be
ineffective to sufficiently restrain axial movement of any
adaptor sleeves used in conjunction with this form ~f con-
:~5 nector.
Against the foregoing background, it i~ an object
of the present invention to provide an improved high voltage
splice connector for high voltage shielded electrical connec-
tors.
Another object of the present invention is to pro- :
vide an improved electrical connector with a minimum number
of parts capable of ready assembly in the field to establish
a reliable connection between high voltage shielded electri~
cal cables. ~ :
A further object of the present invention is to
provide an improve~ connector for high voltage shielded ~:~
cable~ including means for efficiently conveying heat away
from the junction of a plurality of joined cables and serv~
ing the dual function of restraining axial movement of any
20 adaptor sleeves positioned over the insulating jacket o a :
particular cable toward said junction.
According to the present invention there is pro~
vided in an electrical connector having component parts cap-
able of being assembled in the field at termini of high vol-
tage shielded electrical cables for providing a splice connec-
; tlon between first and second such cables, said cables each
having a conductive core surrounded by an insulating jacket
within a conducti~e shield, the shield of each cable termi-
nating æhort of the cable terminus to expose a portion of the
; 30 insulating jacket between the terminus and the termination
of the shield, and the insulating jacket terminating short
of the cable terminus to expose the conductive core between
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the terminus and the termination of the insulating jacket,
~ the combination comprising:
:- a) a pair of sleeves of elastomeric materialr said
sleeves having a conducting portion and an insulating portion, ~ ~-
S one of said sleeves adapted to be secured on each of the cable
ends wlth said conducting portion of eac:h sleeve overlapping
in electrical engagement with thP shield of the respective
cable and qaid insulating portion of each sleeve in engage~
ment with the insulating jacket of the respective cable;
b) connector means for joining the ends of said con-
ductive cores together
c) a housing adapted to overlie said sleeves and said
connector means, said housing having an insulating portion
i and a conducting portion, said conducting portion forming a
15 conductive path bridging said conducting portions of said ~;
. .,
pair of sleeves, said housing insulating portion being in ::
', engagement with said insulating portion of each o~ said pair
of sleeves, said housing defining a chamber surrounding the
connector means; and ;;~
d) a pair of retaining means for precluding axial move- :
ment of said sleeves towards the cable termini and for pro-
viding a thermally conductive path extending between each of
said conductive cores and said housing~ each of said retain~
ing means being adapted to be affixed directly onto one of
said conductive cores in abutting relation with one of said
sleeves and a corresponding insulating jacket.
~ According to a further aspect of the invention there
`1 ~ is pro~ided in a housing for terminating a high voltage cable
having a conductive core surrounded by an insulating jacket
within a conductive shield~ wherein a portion of said conduc-
tive shield is removed to expose a portion of said insulating
jacket and a portion of said insulating jacket is removed to
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expose a portion of said conductive core, said housing in-
cluding a portion adapted to overlie the exposed portion of
said conductive core and an insulating portion and a conduct-
ing portion, an adaptor sleeve having an insulating portion
S in engagement w.ith said housing insulating portion and said
cable insulating jacket and having a conducting portion form- :
ing an electrical path between the conducting portion of said
housing and said conductive cable shield, a retaining means
comprising an annular-shaped member adapted to be directly
affixed onto said conductive core and engage said portion of
said housing adapted to overlie said conductive core, said
retaining means being in abuttiny relationship with the termi-
nation of said insulating jacket and said adaptor sleeve for
precluding axial movement of said adaptor sleeve towards the
terminus of said conductive core, said retaining means being
adapted to provide a thermally conductive path between said
conductive core and said housing.
: Still other objects and advantages of the present
invention will be more apparent from a study of the following
detailed description of the invention with reference to the
; accompan,ving drawing.
Figure 1 is a longitudinal cross-sectional view of
: a fully assembled splice connector according to one prefer-
red form of the present invention;
Figure 2 is an enlarged fragmentary view in cross-
section of the portion of Figure 1 indicated by the broken
circle ~n Figure l;
Figure 3 is a front view in elevation of a preferred :~
~orm of retaining means according to the present invention;
and
Figure 4 is a cross-sectional view taken substan-
tially along line 4-4 of Figure 3.
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Referring now to the drawing, and initially to
Figures 1 and 2 thereof, there is shown one preferred em-
bodimen~ of the pre~sent invention in the form of a splice
connector generally ind.icated by referance numeral 10. The
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splice connector tO i9 Gf the type normally used to form a
waterproof ~oint between a pair of high voltage shielded
electrical cables 12 and 14 in an underground power distri
bution system. Each of the cables t2 and 14 has a centrally
disposed, electrically conductive core 16 surrounded by an
insulating jacket 18 which itself lies within an external
conductive shield 20.
In order to effect a splice connection between the
terminal ends of the cables 12, 14, the housing member 21 is
slîpped over the terminus of one of the cables, say cable 12
and is moved along the cable away from the terminus thereof.
Such movement of the housing member 2t along the cable 12 is
accomplished with little or no resistance since the housing
member 21 is provided with an axially extending internal
bore 23 having an internal diameter considerably larger than
the overall external diameter of the cable. A portion of the
conductive shield 20 is removed so as to expose a portion 22
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of the insulating jacket 18 between each cable termlnus and
the termination 24 of the shield 20. A portion of the in-
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sulating jacket 18 i9 also removed from each of the cables
, 12 and 14 thereby exposing a portion of the electrically
conductive cores 16.
A pair of adaptor sleeves 26 are then slipped over
the terminal ends of each of the cables 12, 14 respectively~
in a direction away from the terminus thereof and positioned
; on each cable substantlally as shown in Figures 1 and 2~ i.e., ~ -
1 with one end 38 of the sleeve in align~ent with the end 40
;~ of the insulating jacket lB.
The adaptor sleeves 26 are preferably fabricated of
an elastomeric material and include a first sleeve portion 28
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of an electrically insulating elastomer, and a second sleeve
portion 30 of an electrically conductive ela~tomer axially
related to and integral with the fir~t sleeve portion 28.
; The ~leeve portions 28 and 30 are preferably molded together
so that the ~leeve portions are contiguous and ~oined together
in a single assembly, the juncture 32 between the sleeve
portions being continuous and void-free. Preferably, the
` compounds of the sleeve portions are based upon the same
polymer to assure strong bonding. An ethylene-propylene
terpolymer, available under DuPont's registered trademark
NORDEL, is an example of a polymer which has been success-
fully used for this purpose. Insulating NORDEL is used for
the first sleeve portion Z8 and conductive NORDEL is used for
the second sleeve portion 30. Alternativelyr the second
sleeve portion 3G may be in the form of a conductive coating,
especially in locations of relatively thin cross-section~
applied to the first sleeve portion 28. For the purposes
of the instant description, the term "elastomer" is meant
to include such coating.
Each adaptor sleeve 26 is provided with an internal
bore 34 which extends axially from end 36 to end 38 of the
sleeve 26 through hoth the first and second sleeve portions
28 and 30, the bore 34 being resiliently dilatable by virtue
of the resilient nature of the elastomeric sleeve material
permitting the sleeve 26 to overlap and snugly engage both
~he insulating jacket 18 and the conductive shield 20 on each
- cable 12, 14. Thus, the conductive portion 30 provided at
the end 36 of sleeve 26 will be in intimate overlapping
electrical engagement with the conductive shield 20 whereas
the insulating portion 28 of sleeve 26 will merely be in
intimate gripping contact with the exposed portion 22 of
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insulatlng ~acket 18 ~hen installed on the ends o the aable~
12 and 14. In this regard, and as menti.oned above, each of
; tha cables i~ in~e.rted into a correspondling sleeve 26 until
- the termlnu~ or end 38 of ~he sleeve 26 i8 alignad ~ub~tan-
tially ~lush with the terminus or end 4CI of thc cable ln~ulat-
ing jacket 18. It will be noted that each sleeve ~6 ha~ an
~ external ~urface 42 common to both portions 28 and 30.
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; Once the adaptor s~eeves 26 are in proper po3ition ~;
upon their rsspective cables, a retainer shown in the form of
~ 10 a retaining collar or ring 44 is slipped over the terminu~
of each cable, urged into an abutting relati~n~hip with the
~lush ends 38 and 40 of each sleeve and insulating jacket, .
re~pectively, and af~ixed to the conductive core 16 o~ each
aable, respectlvely (~ee Fig. 2).
: 15Each retaining ring 44 i~ preferably a~ixed to the
~ core 16 by fastener mean~ shown in the form of a conventional .
:~ screw 46 whlch upon threaded engagement with cooperating nut
48 cau~es the upper portion of the ring 44 to ~lex sllghtly
relative to the lower portion of the ring 44 about the narrow
~ 20 section 49 de~ined by the elongated ~lot 50 provided therein
~ee Pig. 3). Each sleeve 26 i5 thu~ poqitively held in en~
j gagemen* with itB respective cable core 16 and retained against
: movement toward the cable terminus by the retaining ring 44. :~
.. The retaining ring 44 is fur~her provided with arcuate-~haped -~
`:~ 25 ridge~S2 and 54 for protruding into and di~p~aaing a portion
o~ the slee~e end 38 thus posi~ively re~ainin~ the ~leeve 26 . ~:
. in po~itio~ and preventing the ~leeve frem sliding ~ver the
retainlng rlng during ins~allation ~f the housing as will be .. -.~ .
: explained hereina~ter. ~he arcuat~ ~haped ridge~ 52, 54
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~l 30 ~urther improve tha ability o~ the ring 44 to tran~f~r heat .: :
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~rom the core 16 through housing 21 via sleeve 26.
With particular reference to Figs. 3 and 4, each
retaining ring 44 is preferably annular-shaped substantially
as shown, and is fabricated from a material which is both
a relatively good electrical and thermal conductor, such as
for example, aluminum, copper, or hrass or any sui~able epoxy
rasin. The retaining ring is also provided with a centrally
disposed bore 58 which preerably has a diameter generally
equal to the diameter of the cable conductive core 16. The ~:
aforementioned elongated slot 50 extends in a straight line
: from a portion of the outer peripheral edge 60 through the
bore 58 terminating at a point proximate to but spaced in-
wardly from a diametrically opposed portion of the peripheral
edge 60, thus providing the previously described flexure m~ans
in the form of reduced section 49. The reduced or necked-
down section 49 enables the bore 50 to be increased and/or
decreased thereby enabling the retainer ring 44 to be affixed
to a cable core 16 despite dimensional tolerances between
the diameter of the bore 58 and the diameter of the core 16.
The arcuate-shaped ridges 52 and 54 are disposed proximate
the peripheral edge 60 of the retaining ring 44 and function
.to retain the sleeves 26 in position, as noted above~ The
outer periphery 60 of the preferred embodiment of theire~
taining ring 44 is provided with a stepped portion 62 whiah,
in turn, is provided with a through bore 64 extending toward
. and communicating with elongated slot 50, ànd is adapted to
receive the screw 46 as shown most clearly in Fig. 2. A
second stepped portion 66 is also provided in the outer peri-
phery 60 of the retaining ring and includes a similax through
bore 68 in alignment with through bore 64 and is alsv adapted
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. to receive the screw 46. The second stepped portion 66
:~ furthermore defines a bearing surface 70 for the nut 48 and is
adapted to recei~e nut 48 without any portion thereof extend-
ing beyond the outer periphery 60 of the retainincJ .-ing 44.
Threadedly engaging the screw 46 with the nut 48 after the
screw has been inserted into bores 64 and 68 causes relative ~
displacement of the upper and lower portions of the ring 44 ~?
as viewed in Fig. 3 and consequently, a decrease in the di-
ameter of bore 58; thus, when the nut 48 is sufficiently
tightened relative to screw 46, the retaining ring 44 will
be positively and securely affixed to the conductive core 16 :~
- in the position shown, and a good electrical and thermal
path between the core 16 and the housing 21 will be created. ~
j It is contemplated that the retaining ring 44 will .
; 15 be manufactured by a conventional molding or die casting
process thus, the periphery thereof 60 is provided with a
slight slope to facilitate removal from the die or cavity
of the mold. - ~:
Alternative means or affixing the retaining means : ~ .
j 20 onto the core 16, such as for example, by omitting the second ;~
stepped portion 6~ from the retaining ring 44 and providing
a threaded surface interiorly of through bore 68 so that the
screw 46 may be threadedly engaged directly therein, that is, ~ ;
`~ in the lower portion of the ring 44, to enable relative . ~ ~
i;; 25 flexure o ~he upper and lower portions of the ring 44 and ;~:
: to ~irmly and positively secure the ring to the cable core 16, ~ ;
~:1 are considered within the contemplation of the present inven~
tion. -.
~- After securing the retaining rings 44 to the cable
; 30 cores 15r the bared ends of the conductive cores 16 are then
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electrically connected together by mean~ o an electriaal
connector element preferabl~ in the form of the usual tubu}ar
metallic contact or connector 72 having a longitudinal aper-
ture 7~ divided by a transverse wall 76 to establi~h a pair
S of ferrules 78. Thus, eaah conductive core 16 i~ in~erted
into it~ respective ~errule 78 and the contact 72 i~ crimped
in a conventional manner with a tool suited therefor (not
shown) at 80 and 82 to affix the contact 72 to the conductors
16 in a well known manner. It willlbe appreciated t:hat by
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virtue of the retainer ring~ 44 being mounted directly on
the cable cores other known forms of cable core connection
means may he used with the present invention ~uch a~l, weld-
ing, soldering, and 90 on.
It will be noted that the~housing member 21 shown
in Figures 1 and 2 comprlses a composite construction fabrl-
,
cated of elastomeric material. The composite structure - ~
preferably includes a central portion 84 of an electrically ~ `
insulating elastomer and outer and inner portions 86 and 88,
respectively, of an elëctrically conductive ela~tomer. The
central, outer and inner portions 84, 86 and 88, respectively, ~-
are preferably molded together, such as by molding the innex
portion first, then moldiny the central portion around the
inner portion and then molding the outer portion around the
; central portion to form the composite housing member, ~o
that housing member 21 is an integral structure having con-
tiguous inner and outer portions joined in a single assembly.
The junctures between the inner, central and outer portions
are aontinuous and void-free to enable electrical stresses
- to be kept within control along the length of the housing
member 21. The housing member 21 is preferably fabricated
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of the ~ame materials employed in the fabrication o~ the
adaptor sleeves 26.
The .relative dimen~lons o~ thQ central, outer, and
inner portions 84, 86 and 8R x~spectively, are ~uch that aa
the housing member 21 is moved from the~ cable 12 toward the
~ cable terminu~ over the ~l~eves ~.6, met:allic contact 72, and
: , into position over cable 14 a~ shown in Fig. 1, the internal ~:~
bore 23 o the housing is resiliently clilated to formly grlp
the external surface 42 of each sleeve Z6 in watertight :~
rela~ionship therewith and make electrical contact between
the outer conducting portion 86 and the sleeve conducting
portion 30. The central in~ulating portion 84 of the hou~ing
~ 21 makes contaat with the sleeve insulating portion 28 of
,~: each sleeve 26 and the lnner conducting portion B8 of the
housing ~1 make~ electrical and thermal contact wi~h outer
peripheral surface of the pair of retaining ring~ 44 thus
. maintaining a continuous thermal path from the oonductive
core 16 to the housing member 21 and providing an e~uipoten- ~
tial path or chamber 90 ~urxounding the air remaining between :~ ;
the cable conductive core 16, contact membar 72, and the : ~ .
' hou3ing member 21. The continuou~ thermal path thu~ pro- ;
vided facilitates the conduction of heat generated at the
cable te~mini across the gap between the connector 7~ and
the hou~ing member 21, thereby increasing the e~ective ~ ~`
capacity of the ~plice connection 10. At the same time,
since the retaining ring 44 is electrically conductive any
deleterious voltage potential diference between the inner
conducting portion 8~ of the housing 21, the contac~ 72 and
the conductiv0 core 16 is eliminated.
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~ 30 Alternatively, the inner conducting portion 88 of
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the housing 21 may be provided by an additional tubular- ;
shaped member, not shown, bridging the insulating ~acket~ 18
of the cables 12 and 14 and in intimate electrical and
thermal contact with khe outer peripheries 60 o~ the re-
taining rings 44 as well as the inner bore 23 of the hous-
ing 21. While it is contemplated that the housing member 21
is ko be fabricated in the form of a unitar~ housing, it has
been found that a pair of complementary cooperating housing
members as disclosed in the aforementioned United States
Patent No. 3,656,084 may be employed in~tead without de-
parting from the invention.
The combination o the housing 21 with the cor- -
responding adaptor sleeves 26 enahles ready assembly in the
field sinae the sleeves 26 are easily placed in proper posi-
tion upon ths cables by hand without damage to the cable and
especially to the shield thereof. The greater forces needed
to pull the housing 21 over the sleeves 26 are easily applied
to the larger diameter housing member. The sleeves 26 being
secured against movement in resp~nse to such pulling forces
by virtue of the retaining rings 44 being afixed to the
conductive cable core 16, can withstand such pulling forces
and the pulling forces need not he applie~ to the more
delicate conductive shield 20. In addition, as is well
known in the art, cables of different diameters may be
accommodatea without changing the size or configuration of
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- the housing 21 by merely providing adaptor sleeves 26 having
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internal bores of various diameters while maintalnin~ the ~-
external surfaces 42 of the sleeves 26 at the same diameter.
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It has been found that movement of the hou~ing 21
to its proper position as shown in Fig. 1, may be fclcili~ated
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by increa~ing the diameter or ~ore of t:he inner or central
region of the conducting portion 88 relative to the hou~lng
hore 23 with the longitudinal dimension of such increased
bore portion being substantiall~ equal to the longitudinal
~imension of the metallic contact 72 50 as to extend sub-
stantially coextenslve therewith when t:he hou~ing 21 1
located in the position shown in Fig. 1.
Although a pre~erred embodlmen~ has been desarlbed
above, it wlll be under~tood that many variations and modi-
fication~ hereof may occur to those ~killed in the art with-
out departing from the principles of the invention. For
example, the pre~ent lnvention may he employefl ln making a
connsation batween three high volta~e shielde~ aables ln a
~o-called T-splice b~ modification of the hou~ing member ~nd
~! 15 the metallic contact or connector member to permit three
wire~ or cable cores to be Joined together in~tea~ of two.
Other modifications or variation~ will occur to those of
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ordinary ~kill in the art. Accordingly, it is desired that
the 6ubject invention be limited onl~ by the spirit and
scope of the appended claims.
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