Note: Descriptions are shown in the official language in which they were submitted.
CA 02028500 1997-10-06
63632-1301
ENVIRONMENTALLY SEALED PEDESTAL
Background of the Invention
This invention relates to the telecommunication arts and
more specifically to an apparatus and method for sealing a
reenterable splice enclosure and related service connections in a
reenterable protective housing to protect both splices and service
connections against detrimental environmental effects.
Dependency upon telecommunications and data
communications presses the technology to provide consistent high
quality communications with minimal down time. A key to providing
high quality communications with minimal down time is the
protection of installations at critical points and provision for
quick and efficient in-field repairs.
1
X428500
In the delivery of telecommunication services it is
common to install multi-carrier primary cables to provide
communication service to a predetermined area. The primary
cable consists of a number of individual binder groups
consisting of multiple line pairs. At specific points along
the primary cable, connections must be made to route
individual wire pairs to end user locations. Primary cables
are typically very long continuous cables and are not
conveniently manufacturable with specific lengths between
predetermined break off points. Specific binder groups are
extracted from the primary cables and their line pairs are
spliced to a secondary cable. The secondary cable is joined
to a service cable at a terminal block. The service cable is
then routed to an end user location.
The splice connection between the secondary cable
and the primary cable wire pairs and the terminal block
connections must be protected from the environment since
moisture, oxygen, chemicals (both natural environmental and
man-made pollutants) and the accumulation of dust and dirt
may individually or cumulatively act to damage the splice and
terminal block connections. Typically, prior art
telecommunications housings protect a portion of primary
cable and connections in what is referred to as a "pedestal".
A pedestal has an elongated sleeve-like cover structure
having a closed end and an open end which is positioned over
the splice connections and terminal block. To protect the
splice connections and the terminal block from detrimental
environmental effects, the open end of the pedestal cover
must be sealed relative to the pedestal and relative to
entering and exiting cables.
Current pedestal sealing technology can be yet
further improved to improve telecommunications quality, to
minimize down time for or field service repairs to improve
accessibility for field servicing and to improve the
reliability of the installation following field service or
repairs. For example, in one typical prior art arrangement,
-2-
2azs5ao
the seal which seals the pedestal cover to its base is the
only reenterable seal for both the splice connections and the
service connections. The problem with this sealing
arrangement is that access to splice connections is not
required every time a worker works on the service
connections. The splice connections may be sealed with tape,
sealants and the like and hence are difficult to access.
When only the service connections need to be accessed but not
the splice connections, the splice connections are
nonetheless exposed unnecessarily, thereby potentially
decreasing their integrity. Since the splice and service
connections are extremely important to the integrity of the
system it is desirable to avoid unnecessary exposure of
either.
Another example of a prior art pedestal arrangement
is shown in U.S. Patent 4,902,855 to Smith. In this prior
art arrangement, the cables are inserted into a pedestal and
the open end is sealed. Sealing is accomplished through a
labor intensive tape wrapping process. This method forms a
seal which is inherently non-uniform thereby creating
potential for problems with the fit inside of the pedestal
and/or any circumferential compression fitting or clamp used
to engage and seal the structure. Further, depending upon
the type of tape used, ground wires may have to be separately
wrapped prior to incorporation into the common seal. The
sealing arrangement formed is then inserted into the open end
of the pedestal and a shrink tubing is positioned and shrunk
around the outside of the dome to retain the sealing member
therein. Alternatively, a clamp may be used, as shown in the
above-mentioned patent to Smith.
As mentioned above, this type of prior art sealing
system is inherently extremely time consuming and material
intensive. Further, this system risks cutting or otherwise
damaging cable jackets in attempting to remove the shrink
tubing as well as the sealing member when repairing or
modifying splice connections. Additionally, sufficient
-3-
~o~s~oo
supplies such as tapes and shrink tubing must always be on
hand to avoid further delays when installing or repairing
splice connections.
Other prior art arrangements make use of grommet
like members, which must be carefully cut to size and fitted
with the cables and which require additional lubricants for
installation. These grommets must be press fitted within a
bulkhead opening and circumferencially or radially compressed
about a cable or cables for sealing. This arrangement may
also require additional taping of cables and the application
of additional viscous sealants. This arrangement does not
permit easy re-entry once the enclosure is sealed. Nor can
the sealing materials, grommets, etc. be reused after
reentry, rather, the entire above-described process must be
repeated employing a new grommet or grommets and other
materials.
Several problems arise with the prior art in the
installation of the pedestal. Primary cables are typically
laid in the ground by a cable-laying contractor. This
contractor also brings out a loop of cable at each location
where a pedestal is to be installed. After the cables have
been laid, the telecommunications company provides a skilled
installer to form the appropriate cable splices and
connections required at each pedestal location. Each
pedestal location may be very complex and require a
substantial number of cable splices and connections. It can
be seen that the division of labor regarding the installation
of the cable and the connection of the cable is quite
well-defined.
However, some prior art pedestal designs require
completion of all of the splice connections upon initial
installation of the pedestal base and protective dome. It
would be preferable to provide an apparatus which would
permit initial installation of the pedestal base and dome by
-4-
CA 02028500 1997-10-06
63632-1301
the cable-layer, leaving the removal of the cable sheath and
splicing for the qualified technician.
This problem with some prior art designs occurs because
of the nature of the primary cables. Primary cables may include
hundreds of small individual wires which are quite flexible but
which are surrounded by a relatively rigid protective sheath.
When a pedestal is installed, typically there is a base, a
bulkhead, and a dome portion. In the above-mentioned prior art
design, the bulkhead and base member are an integral piece. The
sheath-covered cable is typically much too rigid to insert the
loop brought up by the contractor through an aperture formed
through the bulkhead to receive the cable. Thus, the prior art
design requires the stripping of the sheath from the cable by the
skilled technician in order to install the pedestal, since
allowing the relatively unskilled cable-installer perform the
sheath-stripping operation could cause damage thereto.
The complications discussed above are further increased
due to the nature of the underground communications cable network.
The pedestals are typically the most conveniently available access
node to the cable network, and therefore are extremely important
in the integrity and operation of the network as a whole. If the
pedestal is installed by the cable-laying contractor, the primary
cable may be damaged due to the lack of training and skill in such
technically precise operations. If the connection technician is
left to install the pedestal the loop of primary cable protruding
from the ground is left unprotected until the pedestal is
installed. Further, the connection technician's time is not
5
CA 02028500 1997-10-06
63632-1301
economically spend in the manual, relatively unskilled job of
installing the base of the pedestal thereby increasing
telecommunications costs due to labor inefficiencies.
5a
2028 00
Objects and Summary of the Invention
It is an object of the present invention to provide
an easily enterable and resealable pedestal type enclosure
for protecting sealed cable connections retained therein.
Another object of the present invention is to
provide a sealing apparatus which facilitates ease of access
to the connections for providing efficient access and
resealing of the enclosure.
A more specific object of the present invention is
to provide a reusable sealing member which is axially
compressed to create sealing forces between an opening and
cables projecting therethrough, without the use of additional
sealants, taping, or the like.
Briefly, and in accordance with the foregoing, the
present invention comprises a sealed reenterable protective
housing for protecting telecommunications equipment from
detrimental environmental effects and containing a
reenterable splice enclosure. The protective housing
includes a base portion, a bulkhead member mounted to said
base portion, a dome member selectively attachable to the
bulkhead member and sealing means for selectively sealing the
dome member to the bulkhead member. The dome is selectively
reenterable for accessing the contents thereof while
maintaining the splice enclosure in a sealed condition. The
splice enclosure is selectively disengageable from the
bulkhead member for providing reenterable access to splice
connection retained therein.
Brief Description of the Drawings
The organization and manner of the operation of the
invention, together with further objects and advantages
thereof may be understood best by reference to the following
-6-
2025500
description taken in connection with the accompanying
drawings wherein like reference numerals identify like
elements and in which:
FIG. 1 is partially broken away side view of an
environmentally sealed pedestal which is constructed in
accordance with the present invention;
FIG. 2 is a partially broken away side view of the
environmentally sealed pedestal rotated approximately 90°
from the view illustrated in FIG. 1;
FIG. 3 is an enlarged cross-sectional view of the
environmentally sealed pedestal taken approximately along
line 3-3 in FIG. l;
FIG. 4 is a plan view of a cable sealing plate or
compression member as shown in FIG. 3;
FIG. 5 is a side view of the cable sealing plate
shown in FIG. 4;
FIG. 6 is a front view of a bulkhead used in the
environmentally sealed pedestal of the present invention;
FIG. 7 is a side view of the bulkhead as shown in
FIG. 6;
FIG. 8 is a plan view of a splice sealing member
employed in a reenterable splice enclosure portion of the
present invention;
FIG. 9 is a cross-sectional view of the splice
sealing member taken approximately along line 9-9 in FIG. 8;
FIG. 10 is a cross-sectional view of the splice
sealing member taken approximately along line l0-l0 in FIG.
8;
2028500
FIG. 11 is a plan view of a service cable sealing
member;
FIG. 12 is a partial cross-sectional view taken
approximately along line 12-12 of FIG. 11;
FIG. 13 is a partial cross-sectional view taken
approximately along 13-13 in FIG. 11;
FIG. 14 is an exploded perspective view of the
environmentally sealed pedestal of the present invention;
FIG. 15 is a partial, cross-sectional view of the
environmentally sealed pedestal taken approximately along
line 15-15 in Fig. 2; and
FIG. 16 is a partial, cross-sectional view of the
environmentally sealed pedestal taken along line 16-16 in
FIG. 1.
Detailed Description of the Illustrated Embodiment
While this invention may be susceptible to
embodiment in different forms, specific embodiments of the
present invention are shown in the drawings and will be
described herein in detail with the understanding that such
disclosure is to be considered an exemplification of the
principals of the invention, and is not intended to limit the
invention to the embodiments illustrated and described
herein.
It should be noted that dimensional relationships
between members of the illustrated embodiment may vary in
practice or may have been varied in the illustrations to
emphasize certain features of the invention.
_g-
202850
A reenterable protective housing or environmentally
sealed pedestal 20, is illustrated in FIGS. 1 and 2. The
housing or pedestal 20 is used to protect telecommunications
equipment 22 from detrimental environmental effects. A
primary cable 24 is buried beneath the surface of the ground
26 to protect the cables from the surrounding environment as
well as to remove the cables from sight for aesthetic
purposes. At a position along the primary cable 24 where it
is determined that service drops or cables 28 and/or a field
cable 29 must be run from the primary cable 24, a loop 30 is
formed in the primary cable 24. The pedestal 20 is installed
to contain the looped portion 30 as well as splice
connections 31 made thereto and any additional
telecommunications equipment 22 necessary for distribution of
communications from the pedestal 20 to the service cable 28
and/or field cable 29.
The pedestal 20 includes a base portion 32, a
separate bulkhead member 34 which is removably attachable to
the base portion 32, and a hollow dome member 36 having an
open end 38 releaseably sealable with the bulkhead member 34.
The base portion 32 is preferably formed of metal and extends
a distance below the surface of the ground 26 providing
support for the pedestal 20, protection of the primary cables
24 and loop 30 passing through and into the pedestal 20, and
a potential ground path to the surrounding area. An
environmentally sealed primary compartment 40 is formed
inside of the dome 36 when the dome 36 is sealed to the
bulkhead 34. A wire-routing and connecting portion 42 and a
sealed reenterable splice enclosure 44 are positioned inside
of the primary compartment 40 and operatively attach to the
bulkhead 34. The loop portion 30 of the primary cable 24 is
positioned inside of the reenterable splice enclosure 44 and
splice connections 31 are made to selected wires of the
primary cable 24. A secondary cable 48 and/or a field cable
29 which have been spliced to the primary cable 24 pass out
of the splice enclosure 44. The secondary cable 48 connects
to the service cable 28 at the connecting portion 42. The
_g_
202850
field cable exits through the bulkhead 34 and base 32 to be
terminated or connected elsewhere. The splice enclosure 44
is attached to the bulkhead 34 in a reenterably sealed
fashion so that even when the dome 36 is removed from the
bulkhead 34 the splice connections 31 contained inside of the
splice enclosure 44 are protected from detrimental
environmental effects.
The secondary cable 48 extend out of the splice
enclosure 44 and its individual wires connect to a rear side
50 of the connecting portion 42 (as better shown in FIG. 2).
In the preferred embodiment as illustrated, the connecting
portion 42 includes a rigid plate member 42a which can be
configured to accept one or more terminal blocks 52 of any of
a broad range of configurations and is mounted on a bracket
54. The organization of the terminal blocks 52 permits
attachment of the secondary cable 48 connections to the rear
side 50 of the terminal blocks 52 and connection of the
service cables 28 to a front side 56 of the terminal blocks
52. The service cables 28 connected to the front side 56 of
the terminal blocks 52 extend out of the primary compartment
40 through a service cable aperture 58 formed through the
bulkhead 34 and are routed out through the base portion 32 to
predetermined locations.
The bracket 54 is formed to permit pivotal movement
for selective positioning of the connecting portion 42 when
the dome 36 is removed from the bulkhead 34. For example,
when the dome 36 is removed from the bulkhead 34 the
connecting portion 42 may be moved away from the splice
enclosure 44 generally pivoting downwardly away therefrom
about a pivot pin 60. Selective positioning of the
connecting portion 42 permits complete access to the looped
portion 30 of the primary cable 24, the splice connections 31
and secondary cable 48 retained inside of the splice
enclosure 44. Such access permits efficient operation on the
contents of the splice enclosure 44 as well as connections on
the rear side 50 of the connecting portion 42.
-10-
CA 02028500 1997-10-06
63632-1301
Importantly, and as will be described in further detail
hereinafter, the splice enclosure 44 is sealed to the bulkhead 34
independently of a seal between the dome member 36 and the
bulkhead 34. Such independent sealing permits access to the
primary compartment 40 to operate on the connecting portion 42
without disturbing or exposing the contents of the splice
enclosure 44 to detrimental environmental effects. Further,
selective positioning of the connecting portion 42 further
prevents disturbance of the splice enclosure 44 when the
connecting portion 42 is operated upon.
The pedestal 20 is cross-sectioned along line 3-3 in
FIG. 1 resulting in the view (enlarged) as illustrated in FIG. 3.
It should be noted that cables passing through the bulkhead have
been omitted from FIG. 3 in the interest of clarity. The splice
enclosure 44, connecting portion 42 and bracket 54, and a
compression member or sealing plate 62 are positioned relative to
the bulkhead member 34 to provide efficient access to all of the
components retained in the primary compartment 40.
With further reference to FIGS. 6, 7 and 14, the
interrelationship of the components of the pedestal 20 will be
described in further detail. While different configurations may
be employed in forming the mating or engageable components of the
pedestal 20, the preferred embodiment shown in FIG. 14 shows these
components as being generally circular in shape, while the
components employed in the splice enclosure 44 are generally oval.
As shown in FIG. 14, the primary cables 24 project upwardly
through the base portion 32 and extend through a splice connection
11
CA 02028500 1997-10-06
63632-1301
aperture 64 and are aligned projecting through a surrounding
projecting funnel-shaped aperture 66 integrally formed with the
bulkhead member 34. The looped portion 30 of the primary cables
24 has a portion of an outer jacket 67 removed so that splice
connections 31 may be made with the secondary cables 48. As shown
in FIG. 3, the primary cables 24 and the secondary cables 48
extend through the splice connection aperture 64
lla
zo~s~oo
and are sealed therein by splice connection sealing means
68.
The splice connection sealing means 68 includes a
first resilient sealing member 70 and a two piece shell
member 72. The two piece shell member 72 is formed with a
first half portion 72a and a second half or portion 72b. The
first portion 72a is formed with a hinge portion 72c which
hingedly engages a hinge pin 72d formed in the second portion
72b. Once the hinge portion 72c and the hinge pin 72d are
engaged, the two shell portions 72a, 72b are retainably
engaged by fastener 72f projecting through apertures 72g
formed through flanges 72h opposite the hinge portions 72c,
72d. The first and second portions 72a, 72b form an oval or
circular inner surface or receptacle 72e when joined. The
first resilient sealing member 70 is retained in the
receptacle 72e and is longitudinally or axially compressed
therein between the shell member 72 and a seal neck portion
74.
Sealing of the primary cable 24 and the secondary
cables 48 in the splice connection aperture 64 and projecting
funnel-shaped aperture 66 is accomplished by engaging a
channel 73 formed inside the receptacle 72e of the shell
member 72 with a flange 71 cooperatively formed on the
projecting funnel-shaped aperture 66 and positioning first
resilient sealing member 70 inside the receptacle 72e formed
between the two pieces 72a, 72b of the shell 72. As shown
in FIG. 8, primary and secondary cable apertures 76, 78 and
ground strap apertures 79 are formed through the first
resilient sealing member 70 permitting passage of the primary
and secondary cables 24, 48 and a ground bus 79a (shown in
FIG. 1) therethrough.
A seal neck portion 74 of the splice enclosure 44
is formed with a central aperture 80 through which the
primary and secondary cables 24,48 pass. The seal neck
portion 74 is positioned on top of the first resilient
-12-
zozs~oo
sealing member 70 retained in the shell member 72. The seal
neck 74 is forcibly pressed into the assembled shell 72 so as
to axially compress the sealing member 70 retained therein.
The seal neck portion 74 is attached by means of fasteners 82
inserted through apertures 82a on the sealing neck 74 and
apertured flanges 82b on shell 72. Engagement of the sealing
neck 74 to the shell member 72 maintains axial compression on
the first resilient sealing member 70 retained therebetween
to form a secure releaseable seal between the sealing member
70 and the cables 24, 48 passing therethrough as well as
between the sealing member 70 and projecting funnel-shaped
aperture 66, seal neck portion 74, and the shell member 72.
A suitable cooperating flange 75 may also be provided on the
seal neck 74 to promote correct engagement with shell 72.
With the splice connection sealing means 68
attached to the bulkhead 34 the splice enclosure 44 is
attached thereto for sealing the splice connections retained
therein. A seal is created between an upper sleeve or cover
portion 81 of the splice enclosure 44 and its seal neck
portion 74 by a gasket member 84 positioned therebetween.
The gasket member 84 is positioned and retained in a groove
86 formed on the seal neck base portion 74. The cover 81 is
formed with a spline aperture 88 for receiving a spline 90
therethrough. A spline receiving groove 92 is formed on the
seal neck portion 74 for receiving the spline member 90 when
the cover 81 is positioned over the seal neck portion 74. A
complementary aligned spline receiving groove 92a is formed
on an inner surface of the cover 81. Spline member 90 is
inserted through the spline aperture 88 to engage the spline
receiving grooves 92, 92a formed on the seal neck portion 74
and on the inside of the cover 81 to retain the cover 81 on
the seal neck portion 74.
With reference to FIG. 14, once the spline 90 has
been fully inserted through the spline aperture 88 and the
receiving grooves 92, 92a, a slot 154 formed through a tab
portion 156 formed on the end of the spline 90 defines a
-13-
20285x0
hasp-like structure which may be engaged with a staple or
locking tab 158 formed on the outside of the cover 81.
Engagement of the slot 154 with the staple may be retained by
a further securing device or lock attached to the staple 158
to prevent unintended or unauthorized release of the cover 81
from the seal neck portion 74.
When the splice enclosure 44 is positioned and
engaged as described hereinabove, the splice connections 31
retained therein are protected from detrimental environmental
effects. The cover member 81 may be selectively removed and
reattached as necessary in an extremely efficient manner
without complications such as requiring additional sealing
materials or special tools.
A similar sealing operation is employed to seal the
secondary cables 48 and the service cables 28 passing through
the service cable aperture 58 formed in the bulkhead 34.
Service cable sealing means 94 are employed to seal the
service cables 28 and the secondary cables 48. The service
cable sealing means 94 include the above-mentioned
compression member 62 and a second resilient sealing member
96.' The second resilient sealing member 96 is shown in
greater detail in FIGS. 11, 12, and 13. FIG. 11 illustrates
secondary cable apertures 98, respective service cable and
aerial drop wire apertures 100 and 102 and ground wire
aperture 150 formed in the sealing member 96.
As shown in FIGS. 12 and 13, the apertures 98, 100
are formed with flexible annular frustoconical rings 104
circumferentially lining the inside surface of each of the
apertures 98, 100. The flexible annular rings 104 project
upwardly and inwardly from the surfaces of the apertures 98,
100 at an angle of approximately 45 degrees, and terminate in
rounded inner edges. The flexible annular form of the rings
104 resiliently accommodates irregularities on the outside of
the cables as well as a range of diameters to assure a secure
seal. Other means of accommodating the irregularities of the
-14-
2028500
outside of the cable or different cable sizes may be employed
than those shown in FIGS. 12 and 13, without departing from
the invention.
Similarly, the primary and secondary cable
apertures 76, 78 formed through the first sealing member 70
are circumferentially formed with flexible annular rings 105
having a similar configuration and achieving the same
function as described with regard to the second resilient
sealing member 96. The sealing action of the flexible
annular rings 104, 105 on the insides of the respective
apertures assures a secure seal between the apertures and the
cables passing therethrough when the sealing member 70 is
compressed axially.
The second resilient sealing member 96 is
positioned inside a recess 59 in the bulkhead 34 which
surrounds the service cable apertures 58. The sealing member
96 is compressed by the compression member 62 positioned
thereabove towards the recess 59 in the bulkhead member 34 by
fasteners 106 inserted through apertures 107 and engaged with
bores 108 formed in the bulkhead 34. As shown in FIG. 15 the
compression member 62 engages a top surface 112 of the second
resilient sealing member 96, which is positioned in the
recess 59. A flange portion 109 is formed with fastener
receiving apertures 107 therethrough to promote axial
compression and alignment of the sealing member 96. It
should be noted that the apertures 98, 100, 102 and 150
formed through the second resilient sealing member 96 align
with the apertures 58 and also with the corresponding
apertures 99, 101, 103 and 151 formed through the compression
member 62.
The sealing members 70, 96 described herein above
are composed of a material chosen to provide sealing of the
pedestal 20 over a range of environmental stress factors
including exposure to moisture, temperature, pressure and
certain chemicals. The material chosen should provide
-15-
CA 02028500 2000-03-20
~.
63632-1301
optimum hydrolytic stability, low water absorption, resistance to
dry heat aging, have a low compression set, and also be resistant
to pollution chemicals commonly found in surface soil water
tables. Ideally, the material should not vary appreciably from
its initial properties when subjected to such stress factors in
the field. Preferably, the material should provide acceptable
sealing characteristics at approximately 70°F and maintain
acceptable sealing properties over a full range of temperatures
from -40oF to +140oF.
For example, a preferred set of criteria for sufficient
sealing include a minimum tensile strength of the material of
substantially on the order of 70 psi; a minimum elongation of at
least substantially on the order of 300$; minimum tear resistance
of substantially on the order of 10 lbf/in; and compression set
measured 30 minutes after release of compression, after 8 days at
70°F under 25$ compression of no more than about 2.5$, no more
than about 1.3$, and no more than about 0.8$, respectively,
measured 1 hour, 24 hours and 7 days, respectively, after release
of compression at the end of the 8 days. Preferably, at least the
first and second resilient sealing members 70, 96 are formed of a
polyether or polyester based polyurethane with a Shore A hardness
of 5 to 40, but preferably on the order of A7 to A20. An example
of a material satisfying these criteria is designated as Dexthane~
200 which is a material made by Dexter/Hysol Corporation of
Seabrook, New Hampshire. Another material satisfying most of the
foregoing criteria is designated as Dexthane 400 which is a
material made by Dexter/Hysol Corporation of Seabrook, New
*Trademark
16
CA 02028500 2000-03-20
63632-1301
Hampshire. While Dexthane 400 satisfies most of the foregoing
criteria, it has a nominal hardness of 40 Shore A. Therefore, the
Dexthane 200 material is preferred.
As shown in FIGS. 1, 2, 3 and 14, the bracket 54
comprises mounting members 114 insertable in sockets 160 in the
bulkhead 34. The frame 42a has a base 116 which is attached to
the mounting member 114 by a pivot pin 60 pivotally inserted in an
aperture 116a formed therethrough. As mentioned above, the plate
member 42a may have one or more terminal blocks 52 attached
thereto. The plate member 42a and attached terminal blocks 52 can
pivot about pivot pin 60 forwardly away from the splice enclosure
44 to permit access to the back 50 of the plate member 42a as well
as to permit more open access to the contents of the splice
enclosure 44 when operations are to be affected thereon. The
degree of movement of the plate 42a is limited by a pin 116b
anchored to bracket 54 and inserted through the arcuate slot 116c
formed in its base portion 116. The slot 116c as shown in
*Trademark
16a
2028500
FIG. 16 permits movement through a range of approximately 45°
although other ranges of movement may be achieved by
appropriately modifying the slot 116c.
The bracket 54 is formed of a conductive metal and
includes terminal lugs 117 for electrically joining all of
the ground straps and or ground bars in the pedestal. At
least one further lug 119 is provided to receive ground bus
79a, which projects through apertures 150 and 151, and an
aligned one of apertures 58 into the pedestal base 32.
Pedestal base is provided with a ground lug 123 for receiving
ground bus 79a inside of base 132 and lug 123 also projects
through the base 32 to be connected to further grounding
means if desired.
The dome member 36 attaches to the bulkhead member
34 independently of the splice enclosure 44. A dome flange
122 is formed on the open end 38 of the dome member 36 and is
alignable and engageable with a cooperatively formed bulkhead
flange 124 formed on a peripheral surface 126 of the bulkhead
member 34. A perimeter sealing member 128 is retained on the
bulkhead member 34 abutting the bulkhead flange 124 and is
engageable with the dome flange 122 for sealing the dome 36
to the bulkhead member 34. Selective attachment means such
as a V-band clamp 130 engages both the dome flange 122 and
the bulkhead flange 124 forming a seal with the perimeter
sealing member 128 positioned therebetween.
The spring clip band 130 is formed with a channel
132 which engages the dome flange 122 and the bulkhead flange
124. Initial positioning of the dome member 36 on a radially
reduced shoulder 34a of the,bulkhead 34 permits ease of
installation when the spring clip band 130 is initially
engaged with the bulkhead member 34 and the dome member 36 in
preparation for sealing. The V-band clamp 130 operates with
an over center locking clip 134 which draws opposite ends of
the V-band clamp 130 towards each other to decrease the
circumference of the V-band clamp 130 thereby pressing
-17-
CA 02028500 1997-10-06
- 18 -
together flanges 122, 124 at their generally flared or bevelled
outer surfaces, thereby compressing the sealing member 128
therebetween.
FIGS. 15 and 16 are cross-sectional views taken along
lines 15-15 in FIG. 2 and line 16-16 of FIG. l, respectively. It
should be noted that cables passing through the bulkhead have been
omitted from FIGS. 15 and 16 in the interest of clarity. As shown
in FIG. 15, the bulkhead 34 is in the assembled state as
illustrated in FIGS. 1 and 2. The dome 36 is releasably engaged
with the bulkhead 34 by means of the V-band clamp 130 engaging the
dome flange 122 and the bulkhead flange 124. The engagement
between the dome 36 and the bulkhead 34 is sealed by the sealing
member 128 positioned therebetween. A reduced diameter portion
34b of the bulkhead member 34 is inserted into the base member 32
in a sleeve-like manner and retained thereon by rivets 162 (shown
in FIG. 16) inserted through aligned rivet bores 163, 164 formed
through the base 32 and the bulkhead 34. The connecting portion
42 attached to the base member 116 and the attachment 114 is
engaged with the slots 160 formed in the bulkhead 34.
FIGS. 14, 15 and 16 illustrate the sealing and
engagement of the components comprising the pedestal 20. As shown
in FIGS. 15 and 16, the cover 81 is positioned over the sealing
neck member 74. The cover 81 is retained on the neck member 74 by
the spline 90 inserted through the spline groove 92 formed on the
neck 74 and the cooperatively formed cover spline groove 92a
formed on an inside surface 168 of the cover 81. Sealing of the
cover 81 against the neck member 74 is effected by the O-ring 84
18
CA 02028500 1997-10-06
63632-1301
retained in the O-ring groove 86 formed on the neck member 74
compressed against the inside surface 168 of the cover 81. The
neck member 74 is engaged with the assembled split shell 72 such
that a downwardly facing edge 170 (FIG. 16) compresses the first
resilient sealing member 70 retained inside the receptacle 72e of
the split shell 72. With reference to FIG. 14, a fastener 82 is
inserted through aperture 82a formed through the flange 75 on the
neck 74. A corresponding flange and aperture (see FIG.
18a
2028500
3) are formed for receiving a fastener on the opposite side
of the neck 74 but are not shown in FIG. 14 due to the angle
of the perspective.
The fasteners 82 inserted through the apertures 82a
of the flange 75 are engaged with the apertured flanges 82b
formed on the split shell portions 72a, 72b. Engagement of
the neck 74 with the assembled split shell 72 axially
compresses the first resilient sealing member 70
therebetween. Likewise, the sealing plate 62 axially
compresses the second resilient sealing member 96 positioned
in the recess 59.
Turning again to FIG. 14, temporary mounting clips
175 are shown for use in attaching the dome 36 to the base 32
prior to installation of the bulkhead 34. The mounting clips
175 have forward legs 176 and a rear leg 177 defining a slot
178 therebetween. The slot 178 is positioned over an edge
180 of the base 32 with the forward legs 176 inside the base
32 and the rear leg 177 positioned on the outside of the base
32. With reference to FIGS. 15 and 16, a top portion 179 of
the temporary clip 175 has a cross-section substantially
identical to that of the bulkhead flange 124. The rear leg
177 is formed with an aperture therethrough (not shown) for
receiving a temporary plastic rivet 182 which is inserted
through the aperture 164 formed through the base portion 32.
Thus retained on the base portion 32, the clips 175
may be engaged by the ring clamp 130 to attach the dome 36 to
the base 32 prior to installation of the bulkhead 34. The
ability to install the present invention without installing
the bulkhead 34 is highly advantageous. For example, when
the primary cable 24 is buried beneath the ground 26, it is
extended above the ground in a loop 30 for splicing the
appropriate connections thereto. However, installation of
the primary cable 24 (as noted in the Background of the
Invention hereinabove) is carried out by a cable-laying
contractor who may not have the requisite training to provide
-19-
208500
the required cable connections. Since the necessary
connections can be highly technical and require substantial
training, special telecommunication technicians make the
necessary connections. However, since the sheath 67 covering
the primary cable 24 is generally rigid and rather
inflexible, the sheath 67 must be removed in order to insert
the cable through the neck aperture 64.
Therefore, using the present invention, the
cable-laying contractor may install the entire pedestal 20
except for the bulkhead member 34 and the necessary
connections. This permits allocation of the tasks, manual
tasks to the contractor and technical tasks to the connection
technician, and protects the primary cable 24 extending above
the ground surface 26. When the connection technician
arrives to make the requisite splice connections 31 to the
primary cable 24 and the terminal block connections, the dome
36 is removed from the base 32. Once the dome is removed,
the temporary clips 175 are also removed and the sheath 67 on
the loop portion 30 is removed. Once the sheath is removed,
the cable is flexible enough to be inserted through the
aperture 64 in the bulkhead 34. Once the loop 30 is inserted
through the aperture 64 of the bulkhead 34, the bulkhead 34
is attached to the base portion 32 using the permanent rivets
162 inserted through the apertures 164.
While particular embodiments of the present
invention have been shown and described in detail herein, it
may be obvious to those skilled in the art that changes and
modifications of the present invention in its various
aspects, may be made without departing from the invention and
its broader aspects, some of which changes and modifications
being matter of routine engineering or design and others
being apparent after study. As such, the scope of the
invention should not be limited by the particular embodiments
and specific constructions described herein, but should be
defined by the appended claims and equivalents thereof.
Accordingly, the aim of the appended claims is to cover all
-20-
2028500
such changes and modifications as fall within the true spirit
and scope of the invention.
-21-
