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| United States Patent | 4729064 |
| Link to this page | http://www.wikipatents.com/4729064.html |
| Inventor(s) | Singer, Jr.; Loren A. (Minneapolis, MN) |
| Abstract | A distribution frame comprising interconnect block modules for use in
telecommunications is disclosed. The frame is front accessible for both
wiring and test access. The structure incorporates a reversible wire guide
to facilitate wiring of a module from either the right or left hand side
of a particular mounting bracket. The individual modules incorporate an
overload protector element which utilizes a printed circuit board as a
primary contact structure. The individual modules also use split cylinder
insulation displacement connectors which are readily accessible from the
front of the module and terminate in spring fingers which make contact to
the overload protector elements. |
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Title Information  |
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Drawing from US Patent 4729064 |
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Modular interconnect block with protector structure |
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| Publication Date |
March 1, 1988 |
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| Filing Date |
March 4, 1985 |
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Title Information  |
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References  |
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| *references marked with an asterisk below are user-added references |
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U.S. References |
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| | Reference | Relevancy | Comments | Reference | Relevancy | Comments | 3226669
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|      Your vote accepted [0 after 0 votes] | | 4504883 Uchida 361/119 Mar,1985 |      Your vote accepted [0 after 0 votes] | | 4286836 Rumps 439/406 Sep,1981 |      Your vote accepted [0 after 0 votes] | | 4283105 Ferrill 439/406 Aug,1981 |      Your vote accepted [0 after 0 votes] | | 4255009 Clark 439/398 Mar,1981 |      Your vote accepted [0 after 0 votes] | | 4241970 Rider, Jr. 439/403 Dec,1980 |      Your vote accepted [0 after 0 votes] | | 4236778 Hughes 439/406 Dec,1980 |      Your vote accepted [0 after 0 votes] | | 4210370 Mortimer 303/118.1 Jul,1980 |      Your vote accepted [0 after 0 votes] | | 4163596 Aysta 439/405 Aug,1979 |      Your vote accepted [0 after 0 votes] | | 4160574 DeRoss 439/406 Jul,1979 |      Your vote accepted [0 after 0 votes] | | 4159158 Weidler 439/398 Jun,1979 |      Your vote accepted [0 after 0 votes] | | 4150867 Knickerbocker 439/402 Apr,1979 |      Your vote accepted [0 after 0 votes] | | 4146755 Causse 361/92 Mar,1979 |      Your vote accepted [0 after 0 votes] | | 4057692 DeBortoli 361/7 Nov,1977 |      Your vote accepted [0 after 0 votes] | | 3964816 Narozny 439/397 Jun,1976 |      Your vote accepted [0 after 0 votes] | | 3936133 Splitt 439/54 Feb,1976 |      Your vote accepted [0 after 0 votes] | | 3860318 Reavis, Jr. 439/406 Jan,1975 |      Your vote accepted [0 after 0 votes] | | 3778750 Caveney 439/392 Dec,1973 |      Your vote accepted [0 after 0 votes] | | 3760328 Georgopulos 379/27.01 Sep,1973 |      Your vote accepted [0 after 0 votes] | | | | | |
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| Reasonable Royalty |
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Market Review  |
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Technical Review  |
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Claims  |
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What is claimed is:
1. A distribution frame module, comprising:
(a) a generally rectangular module block having a front face with a
plurality of first apertures and a plurality of second apertures in close
proximity to each of the first apertures and a plurality of third
apertures which are in open communication with said first apertures;
(b) a plurality of wire connectors mounted in recessed position in the
second apertures, said connectors each having a wire terminating end and a
spring contact finger end, the spring contact finger end including a
spring contact finger; and
(c) an overload protector element having an external contact, the element
being mounted in recessed position in one of the first apertures with said
external contact extending into a recessed position in one of the third
apertures to contact at least one of said spring contact fingers also
extending into the recessed position in said one of the third apertures.
2. The module of claim 1, further including wire guide means, the wire
guide means comprising a generally rectangular structure with passageways
for entry of wires along one side thereof and exits along an adjacent
generally transverse side, to facilitate wiring entry and connection of
the block, the wire guide means being mounted to one side of the block.
3. The module of claim 2, wherein the wire guide means is reversible in
assembly to the block.
4. The module of claim 2, wherein the passageways for entry have individual
strain relief means, said passageways being formed to have a lower portion
at an obtuse angle to the exit side of the wire guide means.
5. A distribution frame wherein electrical lines forming portions of an
electrical network are interconnected at said frame, said frame
comprising:
means for protecting said network from transient electrical signals:
means for connecting said lines to said protecting means;
a module with a front face, said module including means for holding said
protecting means and said connecting means said module further including
means for accessing said protecting means and said connecting means
through said front face, said module also including means for routing said
lines from behind said front face to said connecting means;
a bracket which supports said module;
means for grounding said protecting means to said bracket; and
means for attaching said grounding means to said bracket;
whereby said electrical lins are kept behind said front face while said
protecting means and said connecting means are accessed through said front
face.
6. A distribution frame in accordance with claim 5 wherein said module
includes a pair of spaced-apart legs with slots therein and wherein said
bracket includes a pair of spaced-apart tabs for insertion into said
slots, said grounding means including means for contacting said tabs.
7. A distribution frame in accordance with claim 6 wherein said grounding
means includes a strip and a mounting first clip attached thereto, said
first clip receiving said protecting means, said grounding means further
including second mounting clips connecting to said bracket.
8. A distribution frame in accordance with claim 7 wherein said attaching
means includes an aperture in each of said tabs of said bracket and said
second clips of said grounding means each include a projection fitting
into one of said apertures.
9. The distribution frame in accordance with claim 5 wherein said
protecting means includes a circuit board having means for shunting to
ground when heated, said protecting means further including first and
second cover members which fit on at least portions of opposite sides of
said circuit board, said circuit board having contacts extending beyond
said first and second cover members, one of said contacts being received
by said grounding means and another of said contacts being in electrical
contact with said connecting means.
10. The distribution frame in accordance with claim 9 wherein said
connecting means includes a plurality of connectors having a cylindrical
portion from which spring fingers extend, at least one of said spring
fingers contacting said circuit board, said cylindrical portion including
means for contacting and retaining at least one of said electrical lines.
11. The distribution frame in accordance with claim 5 wherein said module
includes a body and a body cover, said module further including a front
cover and means for holding said body, said body cover and said front
cover together, said grounding means being held between said body and said
body cover, said module also accepting said connecting means, said
protecting means being retained by said grounding means.
12. The distribution frame in accordance with claim 11 wherein said module
includes an aperture and a wire distribution recess, said aperture opening
into said recess, said aperture and said recess receiving a plurality of
electrical lines, said module further including a plurality of wire guide
grooves leading from said recess to said connecting means.
13. The distribution frame in accordance with claim 12 wherein said wire
guide grooves include means for relieving strain on said wire extending
therealong.
14. The distribution frame in accordance with claim 11 including a wire
guide and means for attaching said wire guide to said module, said wire
guide providing a plurality of channels which guide said electrical lines
to said connecting means.
15. The distribution frame in accordance with claim 14 wherein said wire
guide includes means for relieving strain on said guided lines.
16. A module for mounting on a bracket of a distribution frame, said module
interconnecting first wires from an incoming feed cable to second wires
from distribution lines, said module comprising:
means for interconnecting a pair of said first wires with a pair of said
second wires, said interconnecting means including means for protecting
said first wires of said incoming feed cable and said second wires of said
distribution lines from harmful signals;
means for grounding said protecting means; and
a primary structure having a front face and a rear, first and second
opposite sides, and first and second opposite ends, said primary structure
holding said interconnecting means and said grounding means, said primary
structure further including first means for routing said first wires of
said feed cable, said first routing means including a recess and an
opening communicating with said recess, said first routing means further
including a plurality of grooves communicating between said recess and
said interconnecting means, said primary structure also including second
means for routing said second wires of said distribution lines to said
interconnecting means.
17. The module in accordance with claim 16 wherein said first routing means
further includes means for relieving strain on said first wires, said
strain relieving means being formed in a portion of said grooves.
18. The module in accordance with claim 16 wherein said second routing
means includes a wire guide having a plurality of passageways extending
from the first end of said primary structure toward the front face of said
primary structure.
19. The module in accordance with claim 18 wherein said second routing
means includes a wall with an edge along said first end of said primary
structure, said second routing means further including means for relieving
strain on said second wires being guided through the passageways, said
strain relieving means including a recess formed between a bulb-shaped
projection and an arrow-shape projection in said wall at said first end.
20. The module in accordance with claim 16 wherein said primary structure
includes a body and a body cover, said primary structure further including
a top cover and means for holding said body, said body cover and said top
cover together, said body cover including an offset portion, said primary
structure also including a wire guide and means for attaching said wire
guide between said offset portion and said top cover.
21. The module in accordance with claim 20 wherein said front cover
includes a plurality of apertures receiving said interconnecting means,
and wherein said wire guide includes a plurality of passageways extending
from the first end of said primary structure to the top cover, said
passageways meeting with said apertures to provide guides for said second
wires from said first end to said connecting means.
22. The module in accordance with claim 21 wherein the first end of said
wire guide includes an end portion which extends beyond the first end of
said body and said body cover, said end portion including means for
relieving strain on said second wires guided by said wire guide, said end
portion including a straight section and an outwardly angled section to
facilitate passage of said second wires through said wire guide.
23. A module for mounting to a bracket of a distribution frame, said module
interconnecting first wires from an incoming feed cable to second wires
from distribution lines, said module comprising:
means for protecting said first wires of said incoming feed cable and said
second wires of said distribution lines from a transient signal carried
along the other, said protecting means including a circuit board having
means for shunting to ground when sufficiently heated, said protecting
means further including means for covering at least portions of opposite
sides of said circuit board, said circuit board having contacts extending
beyond said covering means;
means for connecting a pair of first wires with a pair of second wires,
said connecting means including four connectors spaced about said
protecting means, each of said connectors including a spring finger for
contacting one of said contacts on said circuit board, each of said
connectors further including means for retaining at least one of said
lines;
means for grounding said protecting means;
a primary structure having a front face and a rear, first and second
opposite sides, and first and second opposite ends, said primary structure
holding said protecting means, said interconnecting means, and said
grounding means, said primary structure further including first means for
routing said first wires of said feed cable and second means for routing
said second wires of said distribution lines, said first routing means
including an aperture and a wire distribution recess, said aperture
opening into said recess, said first routing means further including a
plurality of wire grooves leading from said recess to at least two of said
connectors, said wire grooves including first means for relieving strain
on said first wires extending therealong, said second routing means
including a plurality of passageways extending from the first end of said
primary structure to a different two of said connectors, said second
routing means further including second means for relieving strain on said
second wires extending therealong. |
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Claims  |
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Description  |
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TECHNICAL FIELD OF THE INVENTION
The present invention pertains generally to the field of
telecommunications, and more particularly to the structure of distribution
frames comprising modular interconnect blocks for distributing or
cross-connecting incoming telecommunication lines, the blocks including
overload protectors and test access features for such lines.
BACKGROUND OF THE INVENTION
Distribution frames are widely used in the telecommunications industry to
interconnect equipment and distribution lines. Typical distribution frames
consist of a panel containing a number of connection terminals, such as
wire wrapped post or insulation displacement terminals. The terminals are
mounted on panels of flat sheet metal members such that the lines entering
or leaving a particular distribution frame may be connected directly to
the terminals. Typically the distribution lines and the equipment lines
are connected to the rear side of the panel, while the cross-connection
lines between the terminals are connected from the front side.
Distribution frames conventional in the prior art also include "protection"
for operators and equipment. This may be provided either by overvoltage
protection circuits or overcurrent protection circuits which are wired
between the equipment and distribution lines to protect against transfer
from the distribution lines to equipment or equipment operators
environmental hazards such as lightning, the effects of which would
otherwise be routed directly to electrical equipment interfaced with the
lines on the distribution frames.
Distribution frames of this type have many disadvantages. One is that
typically it is difficult to access and test individual lines either in
the distribution line direction or the equipment direction from the front
of the distribution frame panel. Another disadvantage is that many such
systems must be wired from one side of the panel and then cross-connected
from the other side, making access to the panel durring the wiring process
difficult and cumbersome. Third, overvoltage protector devices in the
prior art are often expensive to fabricate, and subject to reliability
problems. Fourth, systems in the prior art typically have different
connection terminals, one set for incoming and outgoing leads and another
set for cross-connect functions, which adds to expense and complexity.
Fifth, many frames currently on the market comprise large panels, as
opposed to a modular approach.
SUMMARY OF THE INVENTION
In response to the above-identified disadvantages of typical distribution
frames, the present invention is directed to a distribution frame made
from a number of interconnect block modules, each of which has equipment
leads, distribution leads, and cross-connect leads connected to front
access terminals. This promotes both simplicity and cost effectiveness in
wiring and testing.
According to one aspect of the invention, a plurality of modules fasten
readily into an associated bracket structure. Each of the modules includes
a plurality of individual circuit protector devices which insert from a
front face thereof. Immediately adjacent the circuit protector structure
is a plurality of insulation displacement terminals, each of which has an
associated spring contact extension which makes contact with the overload
protector. The contact between one of these terminals and the protector
may be broken by a probe insertable into an aperture in the front face of
the module. The probe flexes a finger-like spring contact extension of the
terminal away from the protector contact, at the same time allowing
electrical contact with the individual contact extension for test
purposes.
According to another aspect of the invention, the individual modules have
wire guide structure which provides individual channels for wires to allow
front access to both equipment and distribution line connections. The wire
guide structure further provides for strain relief.
According to still another aspect of the invention, each protection device
includes a two-part cylindrical protector cover, having a printed circuit
board therein, the ends of which extend outward from the protector cover.
The printed circuit board has printed conductors which connect with the
insulation displacement connector contact extensions. The board holds an
overvoltage or overcurrent protector, encapsulated by the protector cover.
The board extends on opposite sides of the protector, one end contacting a
ground clip, and the other end connecting with the associated contact
extensions of the terminals.
The resulting system is compact, cost effective, and provides ready front
access both for purposes of testing and wiring. These and other salient
features of this invention, together with other advantages which result
from various classes of embodiments, are described in more detail in the
following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing one form of bracket for use with a
number of modules of the present invention, one of which is shown
assembled to the bracket;
FIG. 2 is an exploded perspective view of the structure of FIG. 1 showing
various details of construction;
FIG. 3 is an exploded perspective view of a protector element constructed
according to one embodiment of the present invention;
FIG. 4 is a plan view of a module constructed according to the invention as
shown in FIG. 1;
FIG. 5 is a side elevation with portions broken away and shown in
cross-section to illustrate use of the module shown in FIGS. 1 and 4;
FIG. 6 is a sectional view taken generally along lines 6--6 as shown in
FIG. 4;
FIG. 7 is a side elevation of the module as shown in FIGS. 4 and 5 from the
side opposite that which is shown in FIG. 5;
FIG. 8 is a sectional view showing a portion of the mounting structure of
the module;
FIG. 9 is a sectional view taken along lines 9--9 of FIG. 4;
FIG. 10 is a sectional view taken along the lines 10--10 of FIG. 4;
FIG. 11 is an enlarged view of a section of the strain relief of the wire
guide structure shown in FIG. 5;
FIGS. 12 and 13 are sectional views illustrating the test access features
of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
A particular preferred embodiment of a distribution frame including
interconnect block modules according to the present invention is shown in
the drawings. With reference particularly to FIG. 1, there appear portions
of the distribution frame generally designated with reference numeral 10.
Distribution frame 10 is made up of a U-shaped mounting bracket 12, with
the legs of the U having individual pairs of mounting tabs, two pairs of
which are labeled 14, 14, and 16, 16 respectively. Each pair of mounting
tabs accepts an individual interconnect block module 20, so that bracket
12 is configured to accept a total of 10 interconnect block modules 20.
Module 20 is a structure having a pair of individual mounting legs 22, 22,
each of which has a slot or recess into which an associated mounting tab
from bracket 12 fits. As exemplified by the pair of mounting tabs 14, each
mounting tab has a locking aperture 24. Each locking aperture 24
cooperates with a locking clip structure shown in more detail and
described herein-after with reference to FIG. 8.
Each module 20 has a front face 28 on which connections to distribution
lines and equipment are made. Front face 28 also accepts individual
protector elements, as shown more particularly in FIG. 2.
Front face 28 is a portion of a front cover 36 as shown. Front cover 36 is
generally rectangular in shape and has two aperture ears 38 at opposite
ends thereof to facilitate assembly of module 20. Front cover 36 is
provided with a plurality of circularly cylindrical apertures 40. Each of
these apertures is sized to accept an associated overload protector
element 32. Immediately adjacent each aperture 40 are pairs of terminal or
connector apertures 42 and 44.
In the embodiment shown each of these apertures provides access to a wire
connector, both for purposes of wiring and testing. An individual one of
said connectors is labeled with reference numeral 46, and is shown in FIG.
2. This connector is often referred to as a split cylinder insulation
displacement connector, and contains an upper cylindrical portion 48
functioning as a wire terminating end, as well as a spring contact finger
end 49 which includes a pair of contact extensions or spring fingers 50
which extend longitudinally downward therefrom. The upper cylindrical
portion of connector 46 is preferably configured to accept more than one
wire. An example of such structure is shown in U.S. Pat. No. 4,624,521.
Front cover 36 is fitted over module body 54. Module body 54 is structured
to accept twenty pair of connectors 46 across its length. Front cover 36
and body 54 also mate with a body cover 58 to form a closed structure.
Body 54 has an assembly lug 60 at each end thereof. Body cover 58 likewise
has an assembly lug 62 at each end thereof. Lugs 60 and 62 are captured
within the aperture of each of ears 38 in assembly as front cover 36 fits
over body cover 58 and module body 54.
The lower part of module body 54 is provided with an irregularly shaped
recess which supports a ground strip 64 and a pair of mounting clips 66.
Mounting clips 66 may, in a certain class of preferred embodiments, be
spot welded to metallic rectangular ground strip 64. Also attached to
ground strip 64 are a plurality of metal grounding clips 68. Each of
grounding clips 68 attaches to an associated grounding terminal on
overload protector element 32 when it is inserted fully into module 20.
Although two grounding clips are shown in FIG. 2, there would ordinarily
be ten grounding clips spaced offset with respect to the center of ground
strip 64 but longitudinally across the length of strip 64.
Also shown in FIG. 2 is a connecting wire guide 72, which, together with
cover 36, body 54, and body cover 58 make up the primary structure of
module 20. It is contemplated that elements 36, 54, 58 and 72 would
typically be molded from plastic or other suitable non-conductive
material.
Connecting wire guide 72 is basically a rectangular structure with the
exception of a strain relief configuration 74 along the right edge as
shown in FIG. 2. In use, wires from equipment to module body 54 initially
pass through strain relief 74 at the right side of guide 72 then through a
closed rectangular section passageway to any one of a number of
longitudinally spaced wire exits 76 (see also FIG. 5). Wire guide 72 has
two elongate assembly projections 78 along its bottom closed edge.
Assembly projections 78 mate with assembly grooves 82 to lock wire guide
structure 72 as part of the module. A side edge 83 fits flush against a
lower surface 84 of cover 36 so that guide 72 is captivated between an
offset portion 86 of body cover 58 and front cover 36. As shown more
particularly in FIG. 4, front cover 36 has individual wire exit extensions
90 which register with wire exits 76 to provide a continuous passageway
for wire up through front face 28 of cover 36.
As shown in FIG. 5, each passageway 94 is typically capable of directing
two connecting wires and each has a horizontal portion which runs
horizontally and has an arcuate bend portion which gently directs the
wires upwardly to wire exit 76. Also shown in partial section in FIG. 5 is
a portion of front cover 36. Front cover 36, as previously mentioned has a
plurality of wire exit extensions 90 which guide the wires upwardly and
out front face 28. The details of construction of the strain relief of
wire guide 72 are shown more particularly in the enlarged view of FIG. 11
taken in combination with the view of FIG. 5. In FIG. 5, a pair of wires
are shown connected in the right most passageway of wire guide 72. The
connection of these wires 97 to each of a pair of connectors 46 is
protected by means of individual strain relief elements 96. Strain relief
elements 96, in the particular embodiment shown, include a central
arrowshaped projection 100 for each passageway. On each side of the
arrow-shaped projections 100, there is a corresponding bulb-shaped
projection 104. The arrow-shaped outer end of projection 100 and the
bulb-shaped outer end of projection 104 combine to create a narrow
passageway which captivates an individual wire placed through the narrow
entry and into a recess, an example of which is labeled recess 106 in FIG.
11. It will be noted that the strain relief side of wire guide 72 has a
straight section 103 followed by a segment 105 which is angled outward.
This is to facilitate easy connection and passage of wires through the
wire guide. In addition, there are strain relief elements formed on both
the front and back walls 95 of wire guide 72 as appears clearly in FIG. 2.
This permits wire guide 72 to be reversed in a left to right direction so
that wires may enter from either side of mounting bracket 12 to a
particular module.
FIG. 7 shows the reverse side of module body 54, and structure which
provides a mechanism for wiring the reverse side of module 20. In FIG. 7,
there is shown a wire feed aperture 112, which receives wires 113 from an
incoming feed cable 115 for routing to appropriate connection terminals.
Aperture 112 feeds into a wire distribution recess 116 which is generally
trapezoidal in shape and provides a space for individual wires to feed to
each of a plurality of wire guide grooves 118. In a typical structure of
the type shown in FIG. 7, with ten protectors, there are twenty individual
wire guide grooves 118. Although in the fully wired condition each of
these grooves is filled, in the example shown in FIG. 7, only two wires
are fed through aperture 112 across distribution recess 116 and into a
pair of wire guide grooves upwardly for connection to connectors 46. The
reverse side of body 54 as shown in FIG. 7 also includes narrowed sections
120 and 124 at opposite ends of wire guide grooves 118 to provide strain
relief for the wires.
In FIG. 4 of the drawings, associated with each of apertures 40 are four
individual contacts or connectors 46. One pair of connectors 46 accepts
connecting wires from wire exit extensions 90, while the opposite pair
accepts wires from wire guide grooves 118. In use, wire is guided through
the guideways on each of the sides of module 20 including the strain
relief sections, and across the tops of split cylinder connectors 46. A
connection tool 200 having a tip (see FIG. 9) is used to perform wire
cutoff, insulation displacement and wire to connector connection in the
same operation.
Also shown in FIG. 4 are the ends of four overload protector elements 32,
two each at the ends of front face 28. A pair of cross-shaped apertures
130 are formed on opposed sides of each of apertures 40. As shown in FIG.
10, when an overload protector element 32 is placed in one of apertures
40, the portions of the printed circuit board 150 which extend beyond the
cylindrical cover of element 32 slide into elongate cross shaped apertures
130 and downward into the module to make appropriate contact with
grounding clips 68 and connector spring fingers 50. Cross shaped apertures
130 are also used for the purpose of what is typically referred to in the
art as "break access" testing. This is a testing procedure in which a
break in the circuit is made as part of the testing of equipment or of
testing the condition of a distribution line.
As shown in FIG. 3, a first protector cover half 136 is formed to mate with
a second protector cover half 140 to form a cover which is generally
circularly cylindrical in shape. Cover halves 136 and 140 have recesses
144 and 146, respectively, which accept a printed circuit board element
150. At one end of protector cover half 136 is a protector handle 154
which allows ready insertion and removal. At the opposite end of cover
half 136 is a truncated cone shaped end 156. Printed circuit board 150
includes a conventional overload protection device, which in the
embodiment shown is a gas over-voltage protection device having a gas
discharge element 160. Alternatively, over-current protection could be
incorporated on printed circuit board 150. In the embodiment shown, the
element 160 senses an over-voltage cond | | |