Abstrict A structure for mounting an exit sign to a standard wall-mounted
electrical junction box. The structure is constituted of a separate
plate which is adapted to be fastened to the back cover of an exit
sign so as to form a mounting structure adapted for facilitating
the attachment of the exit sign to a wall-mounted electrical junction
box.
Claims What is claimed is:
1. A mounting arrangement for fastening an electrical fixture having
a housing and a planar back cover for said housing to an electrical
junction box which is located in a wall, said back cover having
a centrally located aperture, and latching means arranged about
the perimeter of said aperture; said mounting arrangement comprising:
a plate member positionable over said aperture, latching elements
on said plate member for engaging said latching means so as to fasten
said plate member to the back cover, said plate member including
a center opening for the passage therethrough of electrical wiring
extending from the electrical junction box; and a plurality of holes
extending through said plate member at predetermined locations to
facilitate insertion therethrough of fasteners for mounting said
plate member to said electrical junction box whereby the back cover
is positioned in closely spaced relationship with said electrical
junction box, said aperture in said back cover being circular, a
recessed annular surface portion within said back cover extending
about said aperture, and said latching means comprising resilient
clip elements extending from said recessed annular surface portion
and being located diametrically opposite each other.
2. A mounting arrangement as claimed in claim 1 wherein said plate
member comprises a circular plate having a diameter substantially
the size of the diameter of said aperture, and including a plurality
of radially outwardly extending coplanar flange portions spaced
about the circumference of said plate member so as to be positioned
in surface contact with said recessed annular surface portion in
the back cover.
3. A mounting arrangement as claimed in claim 2 wherein said latching
elements on said plate member comprising diametrically oppositely
located resilient snap elements adapted to latchingly engage into
said clip elements for securing and locking said plate member to
the inner surface of said back cover.
4. A mounting arrangement as claimed in claim 3 wherein said clip
elements include openings for latchingly receiving said resilient
snap elements on said plate member.
5. A mounting arrangement as claimed in claim 2 wherein said latching
elements on said plate member are located on at least some of the
flange portions of said plate member.
6. A mounting arrangement as claimed in claim 1 wherein said latching
means on said back cover and the latching elements on said plate
member are releasably engageable for the detaching of said plate
member from said electrical fixture.
7. A mounting arrangement as claimed in claim 1 wherein said plate
member comprises means for mounting an illumination canopy in said
electrical fixture.
8. A mounting arrangement as claimed in claim 1 wherein said plate
member comprises a blank mounting plate without holes therein for
closing the aperture in said back cover, said blank mounting plate
being a replacement for said electrical junction box mounting plate
member when the electrical
fixture is intended to be side-mounted or top-mounted.
9. A mounting arrangement as claimed in claim 1 wherein said electrical
fixture comprises an exit sign.
10. A mounting arrangement as claimed in claim 1 wherein said
housing is rectangular in shape, said back cover having a planar
back wall and said aperture being formed in the center of said back
wall.
11. A mounting arrangement as claimed in claim 1 wherein said
plurality of holes in said plate member each comprises an elongate
slotted hole to facilitate alignment thereof with fastening structure
in a wall-mounted electrical junction box.
Description BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a structure for mounting an exit
sign to a standard wall-mounted electrical junction box. More particularly,
the invention pertains to a structure constituted of a separate
mounting plate which is adapted to be fastened to the back wall
of an exit sign back cover so as to form a mounting structure adapted
for facilitating the attachment of the exit sign to a wall-mounted
electrical junction box.
The utilization of exit signs which may consist of essentially
rectangular box-like structures having housings with exit legends
illuminated by lighting fixtures arranged in canopies interiorly
of the exit sign is well known and widely employed in the particular
technology. In accordance with specific demands, exit signs may
be mounted on walls, wherein the rear surface or back wall of the
exit sign back cover is adapted to be located in surface contact
with the wall and fastened to a wall-mounted junction box, ordinarily
through the intermediary of screws or other suitable fastening devices,
and with electrical wires or conduits extending from the junction
box to the illuminating elements which are arranged within an exit
sign canopy. Alternatively, the exit sign may also be side mounted
or top mounted and; for example, suspended from a ceiling or extending
outwardly at a generally angular orientation from a wall; for instance,
such as at a right angle thereto.
Ordinarily, the back wall of the back cover of an exit sign housing
when adapted to be essentially flush-mounted to a standard wall-mounted
electrical junction box necessitates that a customer must push or
punch out so-called "knockouts" formed in the back cover
by means of suitable weakening lines, and which initially cover
one or more potential holes which must align with mounting holes
formed in the electrical junction box to facilitate the passage
therethrough of fastening elements. This particular type of assembling
procedure for the components is extremely time-consuming, and is
at times difficult to implement even by experienced electricians
or sign installers. Furthermore, in some instances, complicated
mounting structure must be attached to an exit sign housing or the
like, in which a exit sign canopy bracket structure is designed
to be attached to an electrical junction box mounting plate and
thereafter affixed thereto through the intermediary of suitable
fastener devices.
The foregoing types of exit sign structures and arrangements for
mounting such exit signs to junction boxes, particularly when mounting
the exit sign to a standard wall-mounted electrical junction box
in which the back cover of the exit sign is adapted to be essentially
flush with or closely extend against the wall surface having the
junction box mounted therein, is either difficult to install, or
requires structural components which may be complex and expensive
to manufacture.
2. Discussion of the Prior Art
Johnstone, U.S. Pat. No. 5272605 discloses an exit sign incorporating
a device comprising a canopy mounting bracket wherein, particularly
for top mounting of the exit sign, the canopy bracket is temporarily
fastened to an electric box mounting plate for a wall-mounted or
ceiling mounted electrical junction box. Resilient or spring capture
barb members on the canopy mounting bracket are engaged with the
mounting plate for a junction box in order to provide at least the
temporary fastening prior to the exit sign being permanently attached
to the junction box. This type of structure can also be applied
to side-mounted exit signs; however, it is difficult to install
and is not readily adapted for mounting an exit sign flush against
a wall having a wall-mounted standard junction box arranged therein.
Teisen-Simony, U.S. Pat. No. 4813197 discloses a plate mounting
system, such as for sign posting arrangements, wherein the plate
elements interengage by means of suitable fastener or connecting
elements. There is no disclosure of being able to mount an exit
sign to a standard wall-mounted electrical junction box through
the intermediary of a detachably mounted back plate fastened to
the back cover of the exit sign.
SUMMARY OF THE INVENTION
Accordingly, in order to improve upon the concepts and aspects
of mounting an exit sign on a wall, particularly to facilitate alignment
thereof with a standard wall-mounted electrical junction box, pursuant
to the present invention a back cover for the exit sign housing
includes a large circular aperture having a rim-like surface portion
extending thereabout which includes clip-type latching elements
arranged diagonally opposite each other adjacent the edge of the
circular aperture. In order to provide for the simple attachment
of the back cover of the exit sign housing to the wall-mounted electrical
junction box, there is provided a round junction box mounting plate
which includes radially outwardly extending annular flange portions
each equipped with snap-like latching elements adapted to engage
in openings formed in the clip-type elements on the back cover response
to being rotated through a small rotational angle, whereby the junction
mounting plate will be fixedly engaged on the back cover.
The junction box mounting plate may possess a central opening for
passage thereto of electrical wiring extending from the electrical
junction box which is mounted in the wall, and is provided with
junction box mounting holes dispersed about the perimeter of the
mounting plate which are adapted to be in alignment with mounting
holes in the electrical junction box such that screws or similar
fasteners can extend therethrough for attaching the junction mounting
plate and the back cover of the exit sign which is fastened thereto
to the electrical junction box.
As indicated, the junction box mounting plate which is adapted
to be fastened in position over the aperture formed in the wall
of the back cover for the exit housing has the mounting holes for
electrical junction box preformed therein, so as to obviate the
necessity for punching out of any knockouts, and enabling for ready
alignment with attachment holes of the electrical junction box which
is mounted in the wall.
Suitable canopy mounting and attaching structure may be provided
on the junction box mounting plate for attachment thereto of a canopy
when the exit sign is mounted on a wall-mounted electrical junction
box. The structure and functioning of the canopy mounting and fastening
structure is described in applicants' copending application Ser.
No. 09/124774 (Attorney Docket 740-134 US; 11059), the disclosure
of which is incorporated herein by reference.
When it is desired to have the exit sign either side mounted or
top mounted; in essence, when no electrical junction box mounted
in a wall is adapted to have the sign mounted in a flush relationship
thereon, but rather in which the exit sign is adapted to extend
outwardly from a wall or ceiling, instead of attaching a junction
box mounting plate to the back cover, there is provided a similarly
shaped but essentially blank plate which does not possess any openings
for the passage therethrough of electrical wiring, junction box
mounting holes or canopy mounting structure. In this instance, the
cooperating clip-like latching elements on the back cover and the
snap-like latching elements on the blank plate will merely fastened
the blank plate to the back cover so as to form a closure for the
aperture in the back cover.
Accordingly, it is an object of the present invention to provide
a novel mounting plate arrangement for attaching the back cover
of an exit sign to a standard wall-mounted electrical junction box.
Another object of the invention resides in the provision of a junction
box mounting plate which is adapted to be mounted so as to extend
over a large central aperture formed in the wall of a back cover
for an exit sign housing, and wherein interengageable latching elements
fasten the junction box mounting plate to the back cover so as to
lock these components to each other.
A more specific object of the invention resides in the provision
of a junction box mounting plate of the type described which is
adapted to be fastened to an exit sign back cover to extend over
a large central aperture formed in the wall of the back cover, and
wherein the junction box mounting plate has preformed holes formed
therein which will facilitate the attachment of the mounting plate
in conjunction with the back cover to a standard wall-mounted electrical
junction box.
A further object of the present invention resides in the provision
of a blank plate adapted to be latchingly fastened to the back cover
of the exit sign in lieu of a junction box mounting plate so as
to extend over the aperture in the back cover when it is intended
to either side mount or top mount the exit sign.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference may now be had to the following detailed description
of a preferred embodiment of the invention, taken in conjunction
with the accompanying drawings; in which:
FIG. 1 illustrates a perspective front and side view of the back
cover and housing frame of an exit sign in accordance with the present
pursuant to the invention;
FIG. 2 illustrates a front view of the back cover and housing frame
of FIG. 1;
FIG. 3 illustrates a rear view of the back cover and housing frame
of the exit sign of FIG. 1;
FIG. 4 illustrates a front view of a junction box mounting plate
pursuant to the invention which is adapted to be mounted on the
back cover of the exit sign;
FIG. 5 illustrates a blank mounting plate adapted to be mounted
on the back cover instead of the junction box mounting plate of
FIG. 4;
FIG. 6 illustrates a front view of the back cover of the exit sign,
shown with the junction box mounting plate of FIG. 4 being mounted
thereon;
FIG. 7 illustrates a rear view of the arrangement of FIG. 6; and
FIG. 8 illustrates a perspective view of the back cover and housing
frame for the exit sign as in FIG. 1 shown with the junction box
mounting plate of FIG. 4 being positioned thereon and fastened thereto.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
Referring now in particular to FIGS. 1 to 3 there is disclosed
the back cover 10 and housing frame 12 of an exit sign 14. The housing
frame is of an essentially rectangular peripheral configuration
having upper and lower walls 16 and 18 and side walls 20 and 22
so as to form an encompassing exit sign frame structure, as is well
known in the art. The housing frame 12 includes latching elements
24 adapted to engage complementary latching elements 26 on the upper
and lower flange structures 28 30 forming parts of the peripheral
ledge 32 of the back cover 10. The back wall 34 of the back cover
10 is of an essentially flat or planar configuration.
The housing frame 12 may also be provided with suitable latching
structures 36 at the forward edges of the upper and lower walls
16 18 for latching engagement with a front cover (not shown) of
the exit sign 14. Furthermore, suitable apertures 38 may be formed
in the upper housing wall 16 and apertures 40 in the one housing
side wall 20 which, as may be required, will enable the exit sign
14 to be, respectively, either top-mounted or side-mounted; in essence,
mounted either suspended from a ceiling or extending outwardly from
a wall surface. This type of exit sign mounting is known in the
technology, having reference to the above-mentioned U.S. Pat. No.
5272605.
In the present instance, in order to facilitate the mounting of
the back cover 10 on a standard wall-mounted electrical junction
box (not shown) which is normally mounted flush with or recessed
within a wall, rather than providing so-called "knockouts"
which have been heretofore incorporated in the back covers, and
which must be punched or pushed out to form openings in alignment
with mounting arrangements in the junction box, which is difficult
to implement, pursuant to the invention, the back wall 34 of the
back cover 10 is provided with a large centrally located round aperture
44. Extending about the aperture 44 is an annular recessed surface
portion 46 in the interior surface 48 of the back wall 34 and mounting
latching elements 50 52 for the attachment of a junction box mounting
plate 54 as described in detail hereinbelow.
The latching elements 50 52 are arranged diametrically opposite
each other on the surface of the annular recessed surface portion
46 adjacent the circumference of the round aperture 44. Each latching
element comprises an essentially C-shaped clip with the open end
of each clip facing along the circumference, and in which the outer
leg portion 56 of each latching element clip including a through-opening
58 for engaging a complementary latching element on the junction
box mounting plate 54.
When it is intended to mount the exit sign 14 with its back cover
10 flush against or close to a wall, in which the back cover 10
is to be fastened to a standard wall-mounted electrical junction
box (not shown), the junction box mounting plate 54 as shown in
FIG. 4 of the drawings, is adapted to be fastened to the back cover
so as to extend the aperture in the back wall 34 of the back cover
10 as shown in FIGS. 6 through 8 of the drawings.
As illustrated, the outer diameter 60 of the essentially round
and flat junction box mounting plate 54 is substantially equal to
the diameter of the aperture 44 in the center of the back cover
10 and wherein four (or more) coplanar arcuate tab portions 62
64 66 and 68 extend radially outwardly therefrom, each of which
subtends a short angular extent and is of a radial width substantially
equal to the radial width of the annular recessed surface portion
46 mounting the latching elements 50 52.
As shown in particular in drawing FIG. 4 two diametrically oppositely
located of the tabs 62 66 which each possess a radial width corresponding
essentially to the radial width of the recessed annular surface
portion 46 in the back cover 10 each include resilient snap elements
70 72 extending upwardly therefrom, which when the mounting plate
54 is positioned on the recessed surface portion 46 and rotated
within its plane, the snap elements come into latching engagement
with the openings 58 in the respective therewith associated clip
elements 50 52 formed on the back cover 10 so as to lock the junction
box mounting plate 54 into fixed engagement with the back cover
10 superimposed on aperture 44.
Proximate the snap elements 70 72 on the radially outward extending
tabs 62 66 of the junction box mounting plate 54 are electrical
wire retainer clips 74 76 which are adapted to engage electrical
wires which may be passed through a suitable center hole 78 formed
in the junction box mounting plate 54.
Inventively, the junction box mounting plate 54 is provided with
a plurality of junction box mounting holes 80 which may each be
of an elongate or slotted configuration, and which are suitably
spaced about the circumference of the junction box mounting plate
54 so as to allow for the insertion therethrough of suitable fastener
elements (not shown) for attaching the plate to an electrical wall-mounted
junction box (not shown).
The center region of the junction box mounting plate 54 may also
be provided with a plurality of slot structures 82 and bosses 84
arranged about the center hole 78 for the mounting of an exit sign
canopy, as is described in detail in the copending patent application
Ser. No. 09/124774 of the present applicants.
The foregoing arrangement facilitates the easy mounting of the
junction box mounting plate 54 of FIG. 4 on the recessed surface
portion of the back cover 10 of the exit sign 14 as shown in FIGS.
6 to 8 of the drawings, and eliminates the need for providing knockouts
in the back wall of the back cover 10. When it desired to remove
the mounting plate 54 from the back cover, pressure may be applied
through openings 90 as shown in FIG. 7 so as to disengage the latching
elements, and to then rotate the mounting plate 54 opposite to the
previous direction of rotation.
Once the exit sign 14 is mounted to the electrical junction box,
the latching elements 50 52 facilitate the back plate being locked
into place on the back cover. This prevents the exit sign from being
intentionally or accidentally disengaged from the back plate and
thus from the electrical junction box. The fasteners through which
the junction box mounting plate 54 is mechanically attached to the
electrical junction box must first be removed in order to remove
the exit sign from the wall.
In order to mount the exit sign 14 in a side-mounted or top-mounted
mode, in which the aperture in the back cover is to be closed in
the absence of a junction box behind the back cover 10 instead
of the junction box mounting plate 54 of FIG. 4 there is provided
a blank mounting plate 100 as shown in FIG. 5. This blank plate
has essentially the same overall dimensions and latching elements
70 72 as does the junction box mounting plate 54; in which elements
similar to those in plate 54 are identified by the same reference
numerals. The blank plate 100 eliminates all of the previous elements,
such as the junction box mounting holes, and any slot arrangements
or mounting arrangements for a canopy and the like.
When it is intended to mount the exit sign 14 as a side-mounted
or top-mounted unit, the junction box mounting plate 54 with the
apertures shown in FIG. 4 may be arranged in conjunction with a
canopy for mounting the exit sign to a junction box, whereas the
blank mounting plate 100 is positioned in the back cover 10 of the
exit sign 14.
Pursuant to another aspect, when it is adapted to provide a double-sided
exit sign 14; in effect, viewable from both sides thereof when either
side or top-mounted, in that instance, only the junction box mounting
plate 54 with the mounting holes as shown in FIG. 4 is employed
in conjunction with the canopy. The blank mounting plate 100 as
illustrated in FIG. 5 may then be readily discarded by a customer.
From the foregoing, it becomes readily apparent that the invention
is directed to a simple and inexpensive construction for mounting
an exit sign to a junction box through the intermediary of the inventive
junction box mounting plate 54 which may be utilized either mounted
on the back cover 10 of the exit sign 14 or optionally replaced
by a blank mounting plate 100 or in which the junction box mounting
plate 54 may be utilized for any intended side or top mounting of
the exit sign.
While there has been shown and described what are considered to
be preferred embodiments of the invention, it will, of course, be
understood that various modifications and changes in form or detail
could readily be made without departing from the spirit of the invention.
It is, therefore, intended that the invention be not limited to
the exact form and detail herein shown and described, nor to anything
less than the whole of the invention herein disclosed as hereinafter
claimed. |