Terminal housing for buried communication lines

An airtight, watertight, self-contained housing for buried communication lines, such as telephone lines comprising a main cable and service wires, includes a waterproof housing having a base, a ground stake for installing the housing in the ground, separate compartments formed in the housing below the base to separately receive main cable and service wires, a sealed inner splice chamber above the base, and a sealed outer terminal chamber above the base for enclosing the splice chamber and for containing a terminal block. Main cable passes through the base into the splice chamber which includes a support, an elastomeric seal forming a watertight seal between the main cable entering the splice chamber, and an opening to the chamber through the support. A waterproof inner cover joined to the support by a watertight seal forms the sealed splice chamber. The remaining area of the base has separate, removable screw-threaded plugs with O-ring seals to corresponding holes in the base, each for receiving a corresponding service wire. A service wire is installed by removing a sealed plug, passing the service wire through the hole for connection to the terminal block, and forming a watertight seal around the service wire with an elastomeric grommet. A waterproof outer cover is joined to the base by a watertight seal to form a sealed outer terminal chamber that encloses the terminal block and the sealed splice chamber. Another embodiment of the invention provides a terminal for service wire without use of the sealed inner splice chamber.

FIELD OF THE INVENTION 
This invention relates generally to pedestal and underground terminals for 
buried communication lines, such as telephone and television cables. More 
particularly, the invention relates to an airtight, watertight, 
self-contained terminal housing that is especially useful for the 
efficient installation and trouble-free long term maintenance of 
underground telephone lines. 
BACKGROUND OF THE INVENTION 
Although the present invention can be adapted to providing a terminal for 
buried communication lines of various types, the invention will be 
described with relation to its use as a terminal for buried telephone 
lines. 
In the installation of buried telephone lines, there is a need for a 
terminal that is completely reliable in withstanding adverse weather 
conditions. This includes protecting the buried telephone cable 
installation from water damage, including floods. Hot weather conditions 
prevalent in desert areas also can be a problem for buried telephone line 
terminals. Digital transmission, in particular, requires a dry environment 
inside the telephone terminal housing. 
There is also a need for a terminal for buried cable which is not subject 
to aging or deterioration and which can be immune not only to weather 
conditions described above, but also to salt spray, acid or alkali soils, 
insects, fertilizers, insecticides, or other hostile environments. 
One prior art terminal housing comprises a buried metal box. Loop cable 
passed to the inside of the box is taped to keep out moisture. This 
arrangement has proven unsatisfactory, especially because of its short 
useful life and the additional cost of phone installers to re-install the 
lines when problems arise in the field. 
In addition to protecting telephone line installations from weather 
conditions and other hostile environmental conditions, an underground 
terminal also should reduce installation time and cost initially and as 
further service lines are later connected at the terminal site. Simplicity 
in the installation procedure is particularly useful for service wires 
inasmuch as each service wire installation may, over a period of time, be 
the responsibility of different service personnel. 
The present invention provides a terminal for underground communication 
lines, such as telephone lines, in which the installation at the terminal 
is completely sealed from the environment. The invention is particularly 
characterized by being airtight and watertight to the extent that it meets 
the most stringent of industry imposed standards for long-term protection 
against water damage, heat, and other environmental hazards described 
above. The terminal also is easy to install, can be manufactured at a 
reasonable cost, and facilitates ease of later installation of service 
wire at the terminal site. 
SUMMARY OF THE INVENTION 
One embodiment of the invention comprises an airtight, watertight, 
self-contained housing for buried communication lines, such as telephone 
lines comprising a main cable and service wires. The terminal includes a 
waterproof housing having a base, means for installing the housing in the 
ground, separate compartments formed in the housing below the base to 
separately receive main cable and service wires, a sealed inner splice 
chamber above the base, and a sealed outer terminal chamber above the base 
for enclosing the splice chamber and for containing a terminal block. The 
main cable passes through the base and into the splice chamber which 
includes a support, an elastomeric seal forming a watertight seal between 
the main cable entering the splice chamber and an opening to the chamber 
through the support. A waterproof inner cover is joined to the support by 
a watertight seal to form the sealed splice chamber. The remaining area 
above the base has separate, removable, screw-threaded plugs with O-ring 
seals to corresponding holes in the base, each for receiving a 
corresponding service wire. A service wire is installed by removing the 
sealed plug, passing the service wire through the hole for connection to 
the service block, and forming a watertight seal in the hole around the 
service wire. A waterproof outer cover is joined to the base by a 
watertight seal to form a sealed outer terminal chamber that encloses the 
terminal block and service wire connections, while also enclosing the 
sealed splice chamber. 
Another embodiment of the invention provides a similar terminal that is 
airtight and watertight in sealing service wires extending through the 
base to a terminal block contained in a sealed housing. This embodiment of 
the invention does not contain the sealed splice chamber, and is useful in 
buried (handhole) applications. 
These and other aspects of the invention will be more fully understood by 
referring to the following detailed description and the accompanying 
drawings.

DETAILED DESCRIPTION 
As mentioned previously, the present invention is related to the connection 
of buried communication lines to a terminal installed in the ground. The 
terminal can be a pedestal-type terminal which extends above the ground so 
that access to underground cables and connections in the terminal can be 
readily made by the installer and later by service personnel. The 
invention can be considered an improvement over a previous pedestal-type 
terminal for buried communication lines disclosed in my U.S. Pat. No. 
3,435,124 which is incorporated herein by this reference. Although the 
terminal of this invention can have application to the termination of 
communication lines generally, the invention will be described below with 
respect to a preferred embodiment comprising a pedestal terminal for use 
in the installation and connection of underground telephone lines. More 
specifically, the invention will be described first with respect to a 
pedestal terminal for connection to buried telephone lines which include a 
main cable and separate service wires. The main cable comprises a bundle 
of separate, insulated wires contained in outer shielding which, in turn, 
are contained within an outer insulating jacket, as is familiar to those 
skilled in the art. The service wires are separate shielded wires 
installed one at a time by service personnel who come to the terminal site 
to make installation of service wires when individual service connections 
are required. 
Referring now to the drawings, FIG. 1 is an exploded view illustrating the 
principal system components of a pedestal terminal that provides 
connections for underground telephone lines which can include main cable 
and service wires. The pedestal terminal includes a waterproof housing of 
hard plastic which comprises a tubular outer shell 20 and a ground stake 
22 extending below the shell to provide a means for installing the housing 
in the ground. A circular base 24 extends above the shell and separates 
the ground from connections made internally within the terminal assembly. 
The shell contains a first chamber exposed to the ground below the base 
for receiving main cable as described below, and a separate second 
chamber, also exposed to the ground below the base, for receiving service 
wire as described below. The second chamber is closed by a ground skirt 
door 26. A terminal block 28 extends above the base 24 and includes 
terminal pair connections for service wire extending through the base as 
described below. The terminal block is mounted to a pair of metal supports 
30 projecting above the base and is hinged to these supports so that the 
bottom of the terminal block can pivot about an axis parallel to the base. 
The supports 30 for the terminal block include large openings providing a 
wire run 32. Service wire bond clamps 34 a c mounted in a spaced apart 
relation along a bonding 36 spaced above the base 24. Service wire 
entrance plugs 38 are sealed through the base 24 below the terminal block, 
and these will be described in more detail below. 
The terminal housing also includes a solid copper ground bar 40 projecting 
to the exterior of the housing through the wall of the shell and to the 
interior of the terminal housing. A circular support base 42, made of hard 
plastic integral with the base, projects above the base 24. An upright 
cable bundle support 44 is mounted to the support base 42 of the splice 
chamber. The cable support includes vertically spaced apart, adjustable 
bundle supports or support rungs 46. A terminal stub 48 is secured to the 
bundle support 44. The terminal stub 48 is a continuation of the terminal 
block 28 and enters the splice chamber through a sealed opening in the 
bottom of the support base 40. The wires from the terminal stub are 
connected to wires in a main loop cable in the splice chamber as described 
below. The support base 42 has an interior surface area, described below, 
providing communication to main cable installed through the base 42 for 
connection within the splice chamber as described below. Wires within the 
main cable are bundled and mounted to the adjustable bundle supports. Once 
installation of the main cable is completed, a tubular plastic resin mold 
50 is mounted over the base 42 of the splice housing. An elastomeric inner 
O-ring seal 52 is mounted to the support base 42 in a circular groove 54 
that surrounds the resin mold. An inner cover 56 is then placed over the 
bundle support 44, and mounted atop the inner O-ring seal 52. A flanged 
ring 58 at the base of the inner cover 56 rests on the inner O-ring seal 
52. An inner cover clamp 60 extends around the outer perimeter of the base 
42 and around the flanged ring 58 of the inner cover 56; and the inner 
cover clamp 60, when actuated, is contracted circumferentially around the 
bottom of the cover and the support base 42 to apply pressure through the 
inner O-ring seal 52 to form a watertight seal at the base of the cover 
56. This forms a sealed splice chamber above the base 24 of the housing 
and isolated from the terminal block 28. Bonding ribbons 62 and 63, 
projecting uprightly above the base 42, provide connections to cable 
shield bond clamps on the main cable as described below. 
Once the sealed inner splice chamber has been formed, a tubular hard 
plastic waterproof outer cover 64 is installed over the splice chamber and 
the terminal block 28. An elastomeric outer O-ring seal 66 is mounted to a 
circular groove 68 surrounding the base 24. A flanged ring 65 of the outer 
cover rests on top of the outer O-ring seal 66. An outer cover clamp 70 
then fits around the perimeter of the base, around the outer O-ring seal, 
and around the flanged lower portion of the outer cover. When the outer 
cover clamp 70 is actuated, it contracts circumferentially to apply 
pressure to the outer O-ring seal 66 to form a watertight seal at the base 
of the outer cover 64. 
The following FIGS. 2 through 16 are more detailed views illustrating steps 
in the process of installing main cable and service wires in the terminal. 
FIGS. 2 and 3 illustrate components of the splice chamber in which the 
circular base 42 is held spaced above the base 24 of the housing by a 
lower short riser 72. A circular rim 74 extends around the base on a side 
opposite the riser 72. The O-ring seal 52 is disposed in a circular recess 
around the outside of the circular rim 74. The inner bundle support 44 
with its adjustable support rungs 46 project above the base 42 inside the 
circular rim 74. The circular resin mold 50 can slide vertically along the 
bundle support and can rest on the inside portion of the base 42, inside 
the circular rim 74. Referring to FIG. 3, openings through the base 42 to 
the interior of the splice chamber include a main cable port 76 and a 
branch cable port 78. FIG. 3 also shows means for mounting the bonding 
ribbons 62 and 63 and the terminal stub 48, all of which are sealed by 
watertight seals through an elevated portion 80 of the base inside the 
splice chamber. A branch bonding ribbon is shown at 82 sealed in a 
watertight seal through the base 80. 
FIG. 4 illustrates a lower portion of the housing below the base 24 which 
includes a removable ground skirt section for easy access to multiple 
service wire entrances, each being sealed by a corresponding one of the 
service wire entrance plugs 38. This lower portion of the terminal housing 
includes the removable ground skirt door 26 which rotates open through 
legs 84 releasably disposed in corresponding slotted openings 86 in a 
partition which isolates a compartment for main cable from a compartment 
for service wire, both of which compartments are below the base 24. These 
compartments are exposed to the ground, and the main cable and service 
wires are installed by extending them up through their corresponding 
compartments into the splice chamber and terminal block chamber, 
respectively. 
The removable ground skirt door 26 includes a service wire gauge 90 for use 
in measuring the diameter of the service wire prior to installing the 
service wire in a manner described in more detail below. 
FIG. 5 shows the removable ground skirt door in its closed position, and 
also illustrates connection of the ground bar 40 to the service wire 
bonding bar 36. This figure also illustrates bonding provided with a 
carbon steel external bonding bar 92 installed in the splice chamber. The 
bonding bar 92 is a continuation of the ground bar 40 through the bonding 
bar 36. Field, office and branch bonding ribbons also are shown in the 
splice chamber. The field bond ribbon 62 is shown to the left of the 
office bond ribbon 63, and the branch bond ribbon is shown at 82. The 
field, office and branch bonding ribbons are connected to the bonding bar 
92 and installed into the splicing chamber. 
To install main cable in the terminal housing, a main cable loop or cable 
ends are exposed above the final grade of the ground at the terminal 
location. Cable preparation can follow standard procedures which can 
include scoring the outer sheath and shield above the final grade, 
removing the outer sheath and shield between scores, scoring the inner 
sheath about one inch above the outer sheath, removing the inner sheath 
between scores, and removing the core wrapper. Prior to installing the 
stake assembly 22 in the ground, the outer cover clamp 70 and outer cover 
clamp 64 are removed from the stake, together with the inner cover clamp 
60 and the inner cover 56 being removed from the splicing chamber support. 
The bundle support 44 is then removed from the splicing chamber support, 
and the resin mold 50 also is removed from the splicing chamber support. 
If a branching cable is required, the branch cable entrance plug is 
removed from the base of the splicing chamber. The looped cable or cable 
ends are then fed up through the main cable port 76 in the support base of 
the splice chamber. FIG. 7 best illustrates installation of the main cable 
which shows the main cable in the form of left and right cable sections 94 
and 96 with the insulated electrical conductors 98 of the spliced main 
cable sections extending upwardly above the base 42 and into the interior 
of the splice chamber. The terminal block can pivot down, away from the 
splice chamber, to provide good access for making splice connections in 
the splice chamber, as shown in FIG. 6. 
The main cable sections 94 and 96 are sealed through the base of the splice 
chamber in a watertight seal. The main cable port 76 to the splice chamber 
is oversized relative to the outside diameter of the cable sections, and 
the annulus surrounding the cable is sealed off with a main cable grommet 
100 shown best in FIG. 8. The grommet is preferably made from an 
elastomeric material such as a dense rubber and is in the form of a solid 
block shaped as a figure-eight to match the shape of the main cable port 
76. The sides of the block also are tapered to form a wedge shape so that 
the oversized grommet can be wedged down into the main cable entrance to 
seal around the outside of the cable. 
The grommet has two rounded sections 102, each with a radial split 104. 
Each rounded section of the grommet also has multiple series of circular 
slits 106 concentric with the center of each section (and 
therefore-concentric with the inner axis of the radial split). The 
concentric circular slit extend through most but not all of the depth of 
the block. The grommet is therefore impenetrable to water unless a central 
portion of the grommet is removed to fit around a cable. As shown best on 
the left side of FIG. 8, each radial split makes it possible to pull back 
opposite portions of the grommet on each side of the split to reveal the 
central portion of each rounded section 102 of the grommet. A measured 
portion of the grommet within a selected one of the circular slits can be 
removed to form cable entrances of desired diameters. The grommet enables 
the terminal to be installed on a looped cable or a single cable and still 
maintain a moisture-tight seal. The separate series of slits in the 
grommet are set to fit all cable sizes, and, in one embodiment, these 
cable sizes range from 0.4 inch through 1.2 inch diameter cables. The 
cable diameter is first measured using a measuring gauge that is related 
to the diameters of the concentric circular slits in the grommet. By 
measuring the diameter of each cable, it is then possible to determine the 
amount of rubber to be removed from the slitted region of the grommet so 
the grommet, when closed around the cable, will fit snugly around the 
cable. A measured gauge number indicating the smallest slit is located at 
the center of each grommet cable entrance, and by counting each slit from 
that number stopping at the number indicated on the measuring gauge allows 
the installer to remove the correct unwanted portion of the grommet with a 
pair of snips, so that a correctly fitted sealing grommet has a cable 
entrance hole nearest the cable diameter, yet which completely closes 
around the cable without undue force. The grommet rounded section 102 on 
the left side of FIG. 8 shows a portion of the grommet removed to seal 
around a cable of known diameter. 
As shown best in FIG. 9 once the sealing grommet is properly fitted around 
the main cable sections 94 and 96, the sealing grommet is then pushed into 
the main cable port until the sealing grommet is seated the surface 80 of 
the base 42. This can be done by applying downward pressure on the 
opposite rounded sections 102 of the sealing grommet to wedge it in the 
main cable port in the space around the cable sections 94 and 96. The 
bottom of the can be pushed downwardly in the main cable port to seat on 
an annular flanged shoulder (not shown) at the bottom of the main cable 
port. The cable shield is then bonded in the splice chamber by techniques 
known to those skilled in the art. This includes use of the bonding 
ribbons comprising the office, field and branch ribbons, which hook to 
cable shield bond clamps 103 in the splice chamber. Locations on the 
cables are selected for the cable shield bond clamps that will assure easy 
installation to the bonding ribbons. The bonding ribbons are formed and 
attached to correctly identify cables as shown in FIG. 10. 
Following bonding procedures, the bundle support 44 is replaced the support 
surface 80 of the splice chamber and cables are spliced as required. The 
main cable bundle is then wrapped around a bundle support rung. The resin 
mold 50 is then replaced on the base of the splice chamber. The resin mold 
accommodates, in one embodiment, approximately 30 fluid ounces of resin 
(without cables). The resin is poured into the space inside the resin mold 
and above the seals and over the ends of the cable sheaths so that when 
the resin cures, it will form a permanent airtight and watertight dam 
above the top of the sheath. This seals off the conductors inside the 
cable sheath. 
Following sealing of the splice chamber, the inner O-ring 52 is placed on 
the base 42, and the inner cover 56 is placed over the inner O-ring. The 
inner cover clamp 60 is then tightened to fasten the cover to the base 
forming a watertight seal. 
FIGS. 11 through 15 illustrate installation of service wire within the 
terminal block chamber of the housing. As shown best in FIG. 11, a number 
of the service wire entrance plugs 38 are located on the main base 24 of 
the housing below the terminal block 28 and exterior to the sealed splice 
chamber. To install a service wire, one of the service wire entrance plugs 
normally positioned in the base is removed, and the ground skirt door 26 
is opened to reveal the compartment within the housing below the base 
where service wire can be installed. Opening of the ground skirt door also 
reveals the service wire gauge which can be used to measure the outside 
diameter of the service wire being installed. The wire gauge has six 
tapered openings to measure service wire diameter. The service wire is 
inserted into the larger end of the tapered holes in the gauge, and the 
largest hole that the service wire will not easily pass through determines 
the correct size of the sealing grommet. Each tapered hole has a number 
that corresponds a number on an elastomeric sealing grommet and the 
correctly sized grommet, shown at 110 in FIG. 14, is then fitted around a 
corresponding service wire 112. The grommet is preferably made from the 
same material as the grommet 100 and also is tapered so that it can be 
wedged into the annular space between the service wire 112 and the inside 
of a service wire entrance port 114 extending through the base 24 of the 
housing. 
FIGS. 12 and 13 best illustrate detailed construction of the service wire 
entrance plug 38 which is used to normally seal off a service wire 
entrance port 114 through the base 24. The fastener assembly components 
are preferably made of hard plastic and include a plastic bolt having an 
externally threaded shaft 116 and a bolt head 118 with an annular upper 
surface that seats a resilient compressible O-ring 120. A cap nut 122 has 
a flanged portion with an annular lower rim 124 that rests against the top 
surface of the base 24. A tubular internally threaded shank 126 of the cap 
nut extends downwardly into the service wire entrance port 114. A hex 
section 128 at the top of the cap nut can be used with a hex wrench (not 
shown) for tightening the cap nut against the top of the base 24. Screw 
threaded engagement of the threads of the threaded bolt 116 with the cap 
nut draws the O-ring 120 into pressure contact with an annular rim 130 at 
the base of the service wire port 114. 
Thus, each service wire entrance plug assembly 38, when in its normal 
installed position as illustrated in FIG. 13, provides an airtight and 
watertight sealed base as a partition between the terminal block chamber 
and the portion of the terminal housing below the base 24. When installing 
the service wire 112 as shown in FIG. 14, the service wire entrance plug 
assembly 38 is first removed from the service wire entrance port 114, and 
the service wire is inserted up through the service wire port entrance 
114. The sealing grommet is placed around the service wire to slide down 
within about two inches of its final sealing location. The outside of the 
sealing surface of the sealing grommet and inside of the service wire 
entrance port are lubricated with a suitable lubricant, and the grommet is 
then pressed into the hole around the service wire. The sealing grommet 
then is pushed down farther into the hole approximately to a level 
slightly below the surface of the terminal base 24. The bottom of the 
grommet can seat on an annular shoulder 132 (see FIG. 13) at the base of 
the service wire entrance port through which the service wire is 
installed. Once the service wire is sealed through the service wire 
entrance port, the service wire sheath is removed and the shield of the 
service wire is secured to the bonding bar 36 with corresponding service 
wire bond clamps 34 as shown in FIG. 15. The service wires are then passed 
through the wire runs 32 and attached to the terminal block for 
termination as required. Other service wires passing to the terminal block 
chamber, but not connected to the terminal block, can be stored in the 
wire run provided as an integral part of the terminal block 28. 
Once the service wire terminations are completed, the outer O-ring 66 is 
seated in the circular groove 68 around the base 24, and the outer cover 
64 is then placed over the outer O-ring 66 and the outer clamp 70 is 
tightened to apply pressure through the outer O-ring 66 to form an 
airtight and watertight seal at the base of the outer cover 64. 
Thus, the invention provides a sealed inner splice chamber and a separate 
sealed outer chamber that is easily accessible for service wire 
connections to the terminal block. The outer chamber also provides a 
second additional seal for the permanently installed and sealed splice 
chamber. This maintains lower temperature levels in the more critical 
splice chamber than in the outer chamber which is useful in hot 
environments. The work of splicers and installers is separated, and any 
installations of service wire at a later date simply require removing the 
outer cover, sealing off a service wire passing into the terminal block 
chamber, connecting the service wire and replacing the outer cover. All 
connections of the service wires and main cable are inside completely 
sealed airtight and watertight chambers that can maintain the connections 
long term without being adversely affected by weather or environmental 
hazards. 
FIGS. 16 through 19 illustrate an alternative form of the invention which 
comprises a bracket mounted sealed terminal 140 for buried (handhole) 
telephone cable installations. FIG. 16 illustrates the terminal in its 
closed position, which includes a hard plastic waterproof hollow cover 142 
sealed to a circular base 144. The seal includes an O-ring mounted 
circular groove 145 surrounding the base 144 and a cover clamp 146 for 
tightening around the bottom of the cover 142 and the base to compress 
against the seal. This forms an airtight and watertight seal at the base 
of the closed cover. A circular metal ring 148 is affixed to and extends 
downwardly from the bottom of the base 144, and a metal terminal mounting 
bracket 150 is rigidly affixed to the metal ring 148. The terminal also 
includes a service wire gauge 152 held captive to the outer cover by a 
fixed line 154. 
FIG. 17 shows a terminal with its cover removed to expose the inside which 
includes a terminal block 156 with integral wire run and standard terminal 
connections mounted in an upright position above the base. The terminal 
connections on the terminal block 156 are adapted for connection to 
service wire extending from the area exposed to the ground below the base 
up through sealed openings in the base and to the terminal block. In a 
manner similar to the embodiment of FIGS. 1 through 15, a series of 
circumferentially spaced apart service wire entrance; plugs 158 seal off 
the service wire entrance ports 160 which extend through the base 144. 
These plugs use separate O-ring seals similar to those illustrated in 
FIGS. 12 and 13 to form an airtight and watertight seal through the base 
when no service wire is present in each service wire entrance port 160. 
Service wire is installed in a manner described previously and includes 
removing a service wire entrance plug to expose the service wire entrance 
port 160, pulling the service wire 162 upwardly through the service wire 
entrance port service wire 160, using the gauge 152 to determine the 
proper size of the sealing grommet, affixing the sealing grommet around 
the service wire 162 and press-fitting the grommet in the service wire 
entrance port 160 around the service wire to seal off the space between 
the service wire and the service wire entrance port. The bottom of the 
service wire entrance port includes an annular shoulder against which the 
seal is seated. FIG. 18 shows the top of a grommet 164 sealing off the 
service wire entrance port around the service wire 162. Following seating 
of the sealing grommet around the service wire, the wire is prepared by 
exposing a shielded section 166 which is attached to a bonding crown 168. 
The wires are then extended upwardly through a clamp 170 and to the 
terminal block 156 for connection. 
FIG. 19 illustrates installation of the bracket mounted terminal 140 in an 
underground utility housing 172, which includes a wall bracket 174 affixed 
inside the housing in an upright position. The terminal bracket bracket 
150 can be secured to an upper portion of the wall bracket 174 in a 
temporary upper position until installation is completed after which the 
terminal bracket can be moved to a lower position shown in FIG. 19 and 
rigidly affixed in that position inside the utility housing.