U.S. patent number RE35,075 [Application Number 08/207,822] was granted by the patent office on 1995-10-31 for extension for electrical junction box.
This patent grant is currently assigned to Condulet Adapter, Inc.. Invention is credited to Albert Lammens, Jr..
United States Patent |
RE35,075 |
Lammens, Jr. |
October 31, 1995 |
Extension for electrical junction box
Abstract
An extension box for electrical .[.condulets.]. .Iadd.CONDULET
boxes .Iaddend.or junction boxes can be used by itself as a basic
junction box in an electrical conduit system or as an auxiliary
junction box coupled to a basic junction box to increase the
interior volume of or extend a branch conduit system from the basic
junction box. The body of the extension box has coupling hubs
leading through the body walls to the body interior, for receiving
ends of electrical conduits. Complementary male and female coupling
formations are provided at the open front and back of the extension
box body to permit two or more extension boxes to be coupled in
stacked relation to a conventional junction box such as a
.[.condulet.]. .Iadd.CONDULET.Iaddend.. Removable covers close the
open back of the extension box.
Inventors: |
Lammens, Jr.; Albert (Covina,
CA) |
Assignee: |
Condulet Adapter, Inc. (Del
Mar, CA)
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Family
ID: |
46248420 |
Appl.
No.: |
08/207,822 |
Filed: |
March 7, 1994 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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517508 |
Apr 26, 1990 |
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372132 |
Jun 27, 1989 |
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155985 |
Feb 16, 1988 |
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Reissue of: |
736001 |
Jul 25, 1991 |
05169013 |
Dec 8, 1992 |
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Current U.S.
Class: |
220/3.2; 174/650;
220/3.94; 220/4.26 |
Current CPC
Class: |
H02G
3/083 (20130101); H02G 3/086 (20130101) |
Current International
Class: |
H02G
3/08 (20060101); H02G 003/08 () |
Field of
Search: |
;220/3.2,3.3,3.5,3.6,3.7,3.8,3.92,3.94,4.26,4.27 ;174/50,65R |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1063679 |
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Aug 1959 |
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DE |
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22719 |
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1892 |
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GB |
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Primary Examiner: Gerrity; Stephen F.
Attorney, Agent or Firm: Lyon & Lyon
Parent Case Text
BACKGROUND OF THE INVENTION
Continuing Application Information
This application is a Continuation-in-Part of U.S. Pat. Application
Ser. No. 07/517,508, filed Apr. 26, 1990 and now abandoned, which
in turn is a Continuation of U.S. Pat. Application Ser. No.
07/372,132, filed Jun. 27, 1989 and now abandoned, which in turn is
a Continuation of U.S. Pat. Application Ser. No. 07/155,985, filed
Feb. 16, 1988 and now abandoned.
Claims
What is claimed is:
1. An .[.electrical condulet.]. extension box .Iadd.for an
electrical junction box, .Iaddend.comprising:
a body having sides and ends and a front and a rear;
a shear force carrying rim extending from the front of an outer
perimeter of said body, said rim having an inner wall defining a
coupling opening;
a floor adjacent to and surrounded by said rim, connected to said
body and extending generally perpendicular to said rim, said floor
having front mounting holes and a central opening therethrough;
a boss extending from the rear of said body and having an outer
wall dimensioned to be engageable with the coupling opening, said
boss having rear mounting holes therethrough aligned with the front
mounting holes;
a flat gasket supported on the floor and within the rim; and
means for electrically connecting the front of the body to the rear
of the body.
2. The extension box of claim 1 wherein said rim and body are
substantially ovular.
3. The extension box of claim 1 further comprising at least one hub
extending through the body.
4. The extension box of claim 1 wherein the means for electrically
connecting comprises a conducting element extending from adjacent
the floor to adjacent the back of the body.
5. The extension box of claim 1 wherein the means for electrically
connecting comprises an electrically conducting material.
6. The extension box of claim 1 wherein the ends of the body are
rounded. .Iadd.
7. An extension box for an electrical junction box, comprising:
a body having sides and ends and a front and a rear;
a shear force carrying rim extending from the rim of an outer
perimeter of said body, said rim having an inner wall defining a
coupling opening;
a floor adjacent to and surrounded by said rim, connected to said
body and extending generally perpendicular to said rim, said floor
having front mounting holes and a central opening therethrough;
a boss extending from the rear of said body and having an outer
wall dimensioned to be engageable with the coupling opening, said
boss having rear mounting holes therethrough aligned with the front
mounting holes; and
means for electrically connecting the front of the body to the rear
of the body. .Iaddend. .Iadd.8. The extension box of claim 7
wherein said rim and body are substantially ovular. .Iaddend.
.Iadd.9. The extension box of claim 7 further comprising at least
one hub extending through the body. .Iaddend. .Iadd.10. The
extension box of claim 7 wherein the means for electrically
connecting comprises a conducting element extending from adjacent
the floor to adjacent the back of the body. .Iaddend. .Iadd.11. The
extension box of claim 7 wherein the means for electrically
connecting comprises an electrically conducting material. .Iaddend.
.Iadd.12. The extension box of claim 7 wherein the ends of the body
are rounded. .Iaddend.
Description
FIELD OF THE INVENTION
The field of the invention is electrical junction boxes and
.[.condulet.]. .Iadd.CONDULET junction box .Iaddend.extensions.
.Iadd.CONDULET is a registered trademark of Cooper Industries,
Houston, Texas. .Iaddend.
Building codes require most electrical wiring to be enclosed in
electrical conduit which are coupled to one another by electrical
junction boxes. A typical junction box has a hollow body with at
least one open side, closed by a removable cover. The interior of
the box and conduit coupling hubs extending through the walls of
the box are accessible through the open side(s) of the box. Wires
extend through the conduit into the junction boxes where they are
commonly spliced or joined. Examples of prior electrical conduit
systems and junction boxes are described in U.S. Pat. Nos.
1,741,358; 2,208,558; and 2,398,782.
One widely used junction box for such an electrical conduit system
is .[.known as.]. a .[.condulet.]. .Iadd.CONDULET box.Iaddend.. A
.[.condulet.]. .Iadd.CONDULET box .Iaddend.has a generally oblong
body with one open longitudinal side and curved ends, and conduit
coupling hubs at various locations on the body. .[.Condulets.]. g
CONDULET boxes are assigned various type designations (e.g., C, LB,
LR, LL, T and X) depending on the number and locations of these
coupling hubs. .[.Condulet.]. .Iadd.CONDULET box
.Iaddend.specifications including dimensions, interior volume,
maximum number of conductors, etc. are set forth in Article 370 of
the National Electrical Code Hand Book, incorporated by reference
herein.
.[.Condulets.]. .Iadd.CONDULET boxes .Iaddend.have .[.condulet.].
bodies that form a separate portion of conduit or tubing system.
The inside of a .[.condulet.]. .Iadd.CONDULET box .Iaddend.body is
accessed through a removable cover. Larger cast or sheet metal
boxes are not classified as .[.condulets. Condulets .].
.Iadd.CONDULET boxes. CONDULET boxes .Iaddend.cannot be concealed
or buried underground. Under industry code, they must be above
ground or accessible underground, at all times. They can be
installed indoors or outdoors and in damp locations, are dust proof
and are coated inside and out to prevent corrosion.
.[.Condulet.]. .Iadd.CONDULET box .Iaddend.bodies have threaded
hubs and oblong bodies for ease of pulling wire. Oblong
.[.condulet.]. .Iadd.CONDULET box .Iaddend.bodies are designed for
straight wire pulls, angled wire pulls and Y wire pulls. The oblong
shape of a .[.condulet.]. .Iadd.CONDULET box .Iaddend.body
facilitates pulling wire through it without damaging the insulation
on the wire, by avoiding pulls over sharp corners.
A common problem with .[.condulets.]. .Iadd.CONDULET boxes
.Iaddend.is that they often have insufficient interior junction box
volume to satisfy code requirements. Electrical codes generally
require a certain minimum interior junction box volume per wire
connection in the box. Frequently the number of wire connections
which must be made within a junction box is so large that the box
volume per connection is less than that required by the code. In
addition, with known junction boxes, extending or doubling up an
electrical conduit system requires duplication of components and
supports and makes interconnections difficult or cumbersome.
Accordingly, it is an object of the invention to provide .[.a
condulet.]. .Iadd.an .Iaddend.extension box which is attachable to
a .[.condulet.]. .Iadd.CONDULET box .Iaddend.to provide additional
space for wiring connections.
It is a further object of the invention to provide such a
.[.condulet.]. .Iadd.CONDULET box .Iaddend.extension box which
allows for the expansion or multiplication of an existing
electrical conduit system without the need to cut into the conduit
pipes.
It is a further object of the invention to provide such a
.[.condulet.]. .Iadd.CONDULET box .Iaddend.extension box which is
stackable onto itself, as well as onto .[.condulets.].
.Iadd.CONDULET boxes.Iaddend..
It is a further object of the invention to provide a .[.condulet.].
.Iadd.CONDULET box .Iaddend.extension box which has a rim for
aligning a sealing gasket, aligning the extension box itself onto
another box, and which carries any shear forces.
.Iadd.Of course, the term CONDULET box as used herein is only
exemplary of the general descriptive class of electrical junction
boxes with which the present invention may be employed, and the
present invention is not in any way limited to use with junction
boxes on or in association with which the term CONDULET is used.
.Iaddend.
SUMMARY OF THE INVENTION
The present invention provides a .[.condulet.]. .Iadd.CONDULET box
.Iaddend.extension box which can be used by itself as a basic
junction box or .[.condulet.]. .Iadd.CONDULET box .Iaddend.in an
electrical conduit system, or as an extension box coupled to a
basic junction box or .[.condulet.]. .Iadd.CONDULET box .Iaddend.to
increase the interior volume of and/or extend a branch conduit
system from the basic junction box.
To these ends, an electrical .[.condulet.]. .Iadd.CONDULET box
.Iaddend.extension box includes a body having sides, ends, a front
and a rear. A rim extends from the front of the .[.condulet.].
.Iadd.CONDULET box .Iaddend.extension box body. A floor adjacent to
the rim is connected to the body and extends generally
perpendicular to the rim. The floor has an opening. Screws fasten a
cover to the rear of the body. The screws and body are preferably
made of metal or other electrically conductive material.
Alternatively, a conducting element such as a wire or braid may
extend across the extension box body, from front to back, and
preferably from the floor to the screws at the back of the body. A
boss or protrusion advantageously extends from the rear of the
extension box body, to form a male coupling member, configured to
engage and mate with the rim on the front of the extension box,
which may be used as a female coupling member. A gasket is provided
within the rim on the floor for sealing the box. One or more
coupling hubs pass through the extension box body. The body
advantageously has one or more conduit coupling hubs containing
axial openings for receiving within each hub one end of an
electrical conduit.
The complementary male and female coupling members or formations
provided on opposite open faces of the extension box permit two or
more of the present extension boxes to be coupled or stacked onto a
conventional junction box, such as a .[.condulet.].
.Iadd.CONDULET.Iaddend.. Removable covers close the open back (or
front) of the present .[.condulet.]. .Iadd.CONDULET box
.Iaddend.extension box.
When used as a basic junction box in an electrical conduit system,
the present .[.condulet.]. .Iadd.CONDULET box .Iaddend.extension
box may have one or more conduit coupling hubs arranged like the
coupling hubs of any conventional .[.condulet.]. .Iadd.CONDULET
box.Iaddend..
One or more of the present .[.condulet extension box.].
.Iadd.CONDULET box extension boxes .Iaddend.may also be coupled to
a basic conventional junction box, such as a .[.condulet.].
.Iadd.CONDULET .Iaddend.to either increase the effective interior
volume (to accommodate a large number of wire connections) or to
extend a branch conduit system from the basic junction box.
Preferably, the present .[.condulet.]. .Iadd.CONDULET box
.Iaddend.extension has an oblong shape similar to and is designed
to be coupled to a conventional .[.condulet.]. .Iadd.CONDULET
box.Iaddend..
The interiors of coupled junction boxes communicate through their
adjacent open faces (front and back) whereby wires may extend from
one box to another through these open faces. Each exposed open
front and back, if any, is sealed by a removable cover.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and features of the invention will become apparent
from the following detailed description taken in connection with
the accompanying drawings. It is to be understood, however, that
the drawings are designed for the purpose of illustration only and
are not intended as a definition of the limits of the
invention.
In the drawings, wherein similar reference characters denote
similar elements throughout the several views:
FIG. 1 is an exploded perspective front and side view of the
present .[.condulet.]. .Iadd.CONDULET box .Iaddend.extension
box;
FIG. 2 is an exploded perspective front view of the .[.condulet.].
.Iadd.CONDULET box .Iaddend.extension box of FIG. 1;
FIG. 3 is an enlarged section view taken along line 3--3 of FIG.
1;
FIG. 4 is an enlarged section view taken along line 4--4 of FIG.
1;
FIG. 5 is a side elevation view of the present box used by itself
as a basic junction box in an electrical conduit system;
FIG. 6 is an enlarged side elevation view in part section of the
present .[.condulet.]. .Iadd.CONDULET box .Iaddend.extension box
coupled to a conventional basic junction box (a .[.condulet.].
.Iadd.CONDULET box.Iaddend.) to extend a branch conduit system from
the basic box.
FIG. 7 is a side elevation in part section of the present condulet
extension box coupled to a conventional basic junction box (a
.[.condulet.]. .Iadd.CONDULET box.Iaddend.) to increase the
effective interior volume of the basic box to accommodate a large
number of wire connections;
FIG. 8 is a side elevation view in part section of two of the
present extension boxes coupled in stacked onto a conventional
junction box, such as a .[.condulet.]. .Iadd.CONDULET.Iaddend.;
FIG. 9 is a perspective view of the L.B. .[.condulet.].
.Iadd.CONDULET box .Iaddend.body shown in FIG. 6.
FIG. 10 is an enlarged section view fragment of the stack up of two
extension boxes as shown in FIG. 8; and
FIG. 11 is an alternate embodiment of the present extension box
having swingable links for adapting to varying covers.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to the drawings, and first to FIGS. 1-4 an electrical
.[.condulet.]. .Iadd.CONDULET box .Iaddend.extension box 10 has a
hollow body 12 with an open front 14, and an open back 16 through
which the body interior is accessible. The open front of the body
12 has a rim 18 for receiving or mating with the open back 16 of a
second electrical junction box so that the interiors of the two
boxes communicate through their adjacent open areas. The second
junction box may be a conventional electrical junction box, such as
a .[.condulet.]. .Iadd.CONDULET .Iaddend.as shown in FIGS. 6-8 or
another of the present extension boxes as shown in FIGS. 7 and 8.
The front 14 and back 16 of the extension box body 12 have
complementary female and male coupling formations generally
designated by 20.
The female coupling on the front of the extension box body 12 is
formed by the rim 18 and a floor 22 within the rim. The male
coupling is formed by a boss or projection 26 of the back of the
body 12. Two or more extension boxes may be assembled front to back
with one open back of each box facing an opposite open front of the
adjacent box and with their adjacent coupling formations mutually
interfit and aligned as shown in FIGS. 7 and 8. The rim 18 is sized
and shaped to receive with a close fit the open side of a
conventional junction box, such as a .[.condulet.]. .Iadd.CONDULET
.Iaddend.(FIGS. 6-8). The rim 18 and the floor 22 surround a front
opening 24 in the body 12. The boss or male coupling 26 surrounds a
back opening 28 at the back of the body 12.
The body 12 of the extension box 10 has an oblong shape similar to
the oblong shape of a conventional .[.condulet.]. .Iadd.CONDULET
box .Iaddend.such as the L.B. .[.condulet.]. .Iadd.CONDULET
.Iaddend.shown in FIG. 9. The longitudinal sides 30, 32 of the body
12 join with the opposite curved ends 34, 36. The body 12
preferably has four conduit coupling hubs 38 with intersecting
axes. Each hub 38 contains an axial opening 40 to the body interior
for receiving one end of an electrical conduit. The hub openings 40
are threaded for threaded connection to their conduits. Two of the
coupling hubs 38 are located at the centers of the longitudinal
body sides 30, 32 and on a common transverse axis of the body 12.
The remaining two coupling hubs 38 are located at the body ends 34,
36 on a common longitudinal axis of the body. The extension box may
of course have any number of coupling hubs arranged in any manner,
such as the various .[.condulet.]. .Iadd.CONDULET box
.Iaddend.coupling hub arrangements. Alternatively, if it is
intended solely for the purpose of increasing the interior wire
connection volume of a basic junction box, the extension box 10
need not have .[.no.]. coupling hubs.
FIG. 5 illustrates the present extension box 10 used by itself as a
basic junction box in an electrical conduit system 40. In this use,
the extension box coupling hubs 38 are coupled to wire conduits 42
of the conduit system. The wires within the conduits enter and are
joined within the extension box. The open front 14 and back 16 of
the box are closed by covers 44 which are secured to the box by
screws 46 threaded in holes 48 in the body. The covers are sealed
to the body by gaskets 50. The gasket 50 is self-aligning within
the rim 18 and on the screws 46 on the front of body 12. On the
back of the body 12, the gasket 50 is aligned and secured by screws
46. The gasket 50 seals the extension box body 12 against dust,
vapor and rain. However, the present .[.condulet.]. .Iadd.CONDULET
box .Iaddend.extension box 10 (as well as .[.condulets.].
.Iadd.CONDULET boxes .Iaddend.in general) are for use only in
accessible locations and not for underground or underwater
applications.
FIG. 6 illustrates use of the extension box 10 as an auxiliary
junction box which is secured to a basic junction box 52 of an
electrical conduit system to extend a branch conduit system from
the basic junction box. The basic junction box 52 shown is an
"L.B." .[.condulet.]. .Iadd.CONDULET box .Iaddend.and is shown
separately in FIG. 9. However, it could also be another extension
box 10 such as that illustrated in FIG. 5, or another style
.[.condulet.]. .Iadd.CONDULET box.Iaddend.. The "L.B."
.[.condulet.]. .Iadd.CONDULET box .Iaddend.has an oblong body 54
with an open back 56 and two right angle conduit coupling hubs 58
coupled to electrical conduits 60 of a basic conduit system 62. The
extension box 10 is disposed alongside or piggybacked on the
.[.condulet.]. .Iadd.CONDULET box .Iaddend.52 with the open back 56
of the .[.condulet.]. .Iadd.CONDULET box .Iaddend.set within the
rim 18 of the extension box. The rim 18 has an elongated shape
complementing or matching the shape of the open side of the
condulet body but slightly oversized. The rim 18, as shown in FIG.
6, is used to align and attach a first .[.condulet.].
.Iadd.CONDULET box .Iaddend.extension box 10 to a .[.condulet.].
.Iadd.CONDULET box .Iaddend.52 or to a second .[.condulet.].
.Iadd.CONDULET box .Iaddend.extension box. The rim 18 may be
continuous or discontinuous in the form of segments. The extension
box 10 is secured to the .[.condulet.]. .Iadd.CONDULET box
.Iaddend.52 by screws 64. The opposite open side 16 of the
extension junction box 10 is closed by a cover 66 which is secured
by screws 68 to the body 12 and sealed to the body by a gasket 70.
Screws 64 are accessed by first removing the cover 66.
FIG. 7 illustrates another use of the extension box 10 wherein it
increases the interior volume of a basic junction box 72 to
accommodate a large number of wire connections. As in FIG. 6, the
basic junction box 72 illustrated however is a conventional
.[.condulet.]. .Iadd.CONDULET box .Iaddend.with coaxial end
coupling hubs 74 coupled to wire conduits 76 of a basic conduit
system. The extension box 10 in FIG. 7 is secured over the back
side of the basic box 72 in the same manner as the extension box 10
in FIG. 7 are sealed by plugs 80, whereby the two boxes 10 and 72
effectively form a single larger box capable of accommodating a
large number of wire connections, as shown, while complying with
electrical code requirements which specify a minimum junction box
volume per connection.
In FIG. 8, a plurality of extension boxes 10 are stacked onto the
open back of a basic junction box 82 to function a auxiliary
junction boxes for extending branch conduit systems from and/or
increasing the effective interior wire connection volume of the
basic box. The illustrated basic junction box 82 is a
.[.condulet.]. .Iadd.CONDULET box .Iaddend.like that in FIG. 7
although the basic box could be another extension box. The
extension box 10 adjacent the basic box is secured to the latter
box in the same manner as the extension boxes 10 in FIGS. 6 and 7.
The adjacent extension boxes 10 are disposed with the open front 14
of one box and the opposite open back 16 of the adjacent box facing
one another and with the male coupling formation 20 of the one box
seating in the rim of female coupling formation 18 of the adjacent
box, as shown. The adjacent extension boxes are joined by screws
84, and the open back of the outermost extension box 10 is closed
by a cover 86.
As shown in FIGS. 6 and 8, the rim 18 provides 3 advantages:
1) It facilitates alignment and support of the extension box 10
onto the basic box 52 or 82. The electrician need only place the
extension box 10 over the open back of the basic box 52 or 82. In
marginally accessible locations or tight spaces, this can be done
with one hand. The rim, as shown in FIG. 6, allows the extension
box 10 to hang onto the basic box while the screws 64 or 84 are
installed. The rim also causes the screw holes in the extension box
to align with the screw holes in the basic box. Accordingly, the
rim obviates the need for the electrician to manually support and
align a .[.condulet.]. .Iadd.CONDULET box .Iaddend.and its screw
holes during installation.
2) The rim provides a structure for carrying shear forces between
boxes. As shown in FIG. 6, the boxes are supported on conduit
pipes. Tolerance build ups often cause a mismatch of alignment
between the boxes. This makes it difficult to install the
attachment screws 64 or 84. In the prior art, all shear force
between the boxes is necessarily carried only by the 2 screws
resulting in high shear stress on the screws and the possibility of
excessive strain, failure, stress enhanced corrosion, etc. The rim
18, when secured over a basic box 54 or 82, centers the screw holes
ideally with the screws placed only in tension when tightened. The
rim surrounds the basic box on all sides so that any plane shear
forces between the extension box 10 and basic box are carried by
the rim and not the screws. Of course, part of the effectiveness of
the rim's absorption of shear loads depends on the tolerances and
fit between the tim and basic box.
3) The rim centers, supports and aligns the gasket 50. During
installation, the gasket 50 need only be placed within the rim 18.
The rim holds and aligns the gasket so that the clearance holes in
the gasket align with the clearance holes in the .[.condulet.].
.Iadd.CONDULET box .Iaddend.extension box 10. This also simplifies
installation since the gasket need not be separately handled after
it is placed within the rim.
.[.Condulets.]. .Iadd.CONDULET boxes .Iaddend.are made of various
types of conductive material to provide grounding and reduce the
risk of electrical shock. The extension box 10 is also preferably
made of an electrically conductive material. Alternatively, an
electrically conducting element such as a metal braid, ribbon or
wire can be provided within a non-electrically conducting extension
box body 12 running from the front of the box (e.g., from the rim
14 or floor 22) to the back of the box (e.g., to the boss 20 at the
back of the extension box), to provide electrical conductivity
across a stack up of extension boxes.
As shown in FIG. 6, the metal screws 64 holding the extension box
10 to the .[.condulet.]. .Iadd.CONDULET box .Iaddend.52 not only
rigidly attach the two boxes together, but they also ground the two
boxes together by providing electrical conductivity or continuity
between the extension box .[.1.]. .Iadd.10 .Iaddend.and the
.[.condulet.]. .Iadd.CONDULET .Iaddend.box 52. When a cover is
attached to the extension box 10, as shown in FIG. 2, the cover is
grounded to the body 12 through the electrical path provided by the
screws 46 into the mounting holes 48 in the body. When the
extension boxes 10 are stacked, e.g., as shown in FIG. 8, the
screws 84 (together with the electrically conductive body or
conducting element) provide a continuous electrically conductive
path throughout the entire stack up. Since the metal screws pass
through the gasket 50, the gasket does not interfere with
electrical continuity.
The extension box 10, when attached to a .[.condulet.].
.Iadd.CONDULET box .Iaddend.52 in an existing conduit system 62
allows additional hubs to be added without cutting into the piping
or conduit system 60 or installing additional junction boxes or
.[.condulets.]. .Iadd.CONDULET boxes.Iaddend..
FIG. 11 shows an alternate embodiment of the extension box 100
having .[.boxes.]. .Iadd.bosses .Iaddend.102 extending from the
sides of the box. The bosses 102 have threaded holes 104. Links 106
are secured to the bosses 102 by screws 108. The links 106 have
threaded cover mounting holes 110 at one end. Some .[.condulets.].
.Iadd.CONDULET boxes .Iaddend.have covers with varying hole
patterns. The extension box 100 can use these covers by swinging
the links to the position where the holes 110 align with the holes
in the cover.
Many changes, modifications, variations and other uses and
applications of the subject invention .[.with.]. .Iadd.will
.Iaddend.become apparent to those skilled in the art after
considering this specification together with the accompanying
drawings and claims. All such changes, modifications, variations
and other uses and applications which do not depart from the spirit
and scope of the invention are deemed to be covered by the
invention which is limited only by the claims which follow.
* * * * *