Note: Descriptions are shown in the official language in which they were submitted.
1 307578
UNIYERSAL BRACKET F~R_SUPPORTING AN~ CTRICAL ~0
The present inven'cion relates to a bracket for
supporting an electrical box in a hollow wall structure.
More specifically, the present invention provides a bracket
that can be adapted to hold electrical boxes of most
standard sizes to fit recessed within hollow wall
structures of different depths.
Most interior wall structures are hollow and consist
of a stud skeleton with wallboard coverings. The studs in
non-combustible wall structures are made of thin flexible
sheet ~letal and the rigidity of the walls is achieved by
attaching stiff wall boards to both sides of the studs.
Electrical boxes for outlets, switches and the like
are attached at one side to a stud, but on the other side-
they require some type of support within the hollow wall
structure, otherwise the box can move, pivoting about the
supported side. Brackets are, therefore, provided to
support the free side of the box and hold it rigid so that
pushing an electrical plug into an outlet or pulling a plug
from an outlet does not move the electrical box within the
wall structure.
Universal support brackets may be provided to support
the box at the side opposite from the stud. Examples of
- such brackets are disclosed in co~pending Canadian patent
applications serial number 523,966 and 523,967 filed in the
name of William Nattel. These braokets all provide a stop
to prevent the boxes being pulled out oP the wall. In some
cases, they also provide tabs to prevent the box being
pushed into the hollow space within the wall area.
However, these tabs which are bent to suit a particular
size of box, do not always provide a positive attachment
and sometimes during installation, the tabs may not have
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been bent to the correct position which can permit them to
slide off the backside of the box. If this occurs, then
the brackets do not provide a positive attachment for
holding the side of the box.
It is an aim of the present invention to provide a
~ support bracket that positively attaches to one side of
;~; different sizes of electrical boxes and hold the box
rigidly within the wall structure preventing it ~rom either
being pushed in or pulled out. The bracket positions the
electrical box so that it is either flush with or recessed
from the outside surface of the wall, supported on one side
by the support bracket and on the other side by a stud
within the wall structure.
It is another aim of the invention to provide a
universal support bracket for positively attaching to one
side of electrical boxes of different depths and fit within
different depths of hollow wall structures.
The present invention provides a universal support
bracket for attaching different sizes of electrical boxes
in hollow wall structures of different depths, the wall
structure being formed with a plurality of studs spaced
apart with a wall board covering, the bracke~ comprising: a
flat elongate strip of sheet material; one end of the strip
having a~ least one tab extending in the plane of the
strip, the tab adapted to be bent to form a hook means for
engaging a side wall of an electrical box, an arm having a
first flange at the one end of the strip substantially
perpendicular to the strip; a plurality of locking tongues
spaced apart at intervals on each side of the strip, each
of the tongues having a locking portion facing the one end
of the strip, and a bend line such that at least one of the
; tongues may be bent so the locking portion L its into a slot
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provided in the electrical box, the other en~ of the strip
.~ having a second flange bent perpendicular to the strip, and
at least one bend line across the strip such that a portion
of the strip adjacent the-other end may be bent
substantially perpendicular to the strip to accommodate a
different depth of hollow wall structure.
In another embodiment, two tabs are provided, one on
each side of the arm having the first flange at the one
end, two tabs are adapted to be bent on the bend line to
form a hook for engaging a side wall of an electrical box.
In a further embodiment, two locking tongues, one on
each side of the strip, are provided for an electrical box
of a certain size, the two locking tongues have bend lines
where the two locking tongues may be bent so the locking
positions fit into slots provided in the electrical box.
Referring now to the drawings:
FIG 1 is a plan view of one embodiment of a support
bracket;
FIG 2 is a side view of the support bracket shown in
FIG 1;
FIG 3 is an isometrio view of the support braoket
shown in FIG 1 with hook portions at one end bent out,
FIG ~ is an isometric view of an electri.cal box
~ showing slots on the baok side adjaoent one edge for the
: 25 locking tongues of the support bracket to engage;
FIG 5 is a side view of the bracket shown in FIG 1
holding one side of an electrical box recessed in a wall
structure;
FIG 6 is a side view of the bracket shown in FIG 1
holding one side of a shallower electrical box recessed in
a thinner wall structure than FIG 5.
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One embodimenk of ~ universal support brac~et 10 is
illustrated in FIGS 1 2 and 3. Bracket 10 is preferably
stamped out of sheet metal and has a flat elongate strip 12
extending down to two si~ilar flat portions 14 having a
bend 16 as shown in FIG 1 to allow the flat portions 14 to
to form two hooks. The hooks are to hold one edge of the
side of an electrical box. FIG 3 shows the two portions 14
ben~ to about 90, ready for engaging a side of an
- electrical box.
In between the two flat portions 14 is an arm 18
raised from the elongate strip 12 and divided from the two
side portions 14 by grooves 20. At the end of the arm 18
is a first flange 22 which is used for positioning the
bracket within the wall structure and rests on the inside
surface of a wallboard.
At the other end of the strip, a second flange 24
extends substantially perpendicular from the end of the
strip 12 on the same side as the first flange 22. The
bracket is arranged to fit within a wall structure having a
stud the same thickness as the distance between the first
flange 22 and the second flange 24. A bend line 26 is
~; illustrated partway down the strip 12 and if a smaller stud
is provided in the wall structure, then the bracket may be
bent at this bend line 26 providing another flange which
~' 25 supports the bracket on ~he insides of the two wall boards.
The strip may be bent about the bend line 26 by means of
pliers.
Whereas one bend line 26 is shown in FIG 1, two or
more bend lines may be provided in the strip 12 to fit
different wall structures. There are generally two sizes
of studs or channels used in the construction of a wall
structure, a 3 5/8" stud and a 2 1/2" stud.
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Two pairs o~ locking tongues 30 and 32 are provided
on each side of the strip 12 with bend lines 34 in line
with the strip 12. One tongue on each side of the strip
forms a pair of tongues and each tongue has a notch 3~ for
engagement into a slot on the back surface of an electrioal
box as will be illustrated herea~ter. The pair o~ tabs 30
are for a deeper box than the pair of tabs 32. Whereas two
sets of tabs are shown herein, more than two sets of tabs
could be provided if required. A reinforcing rib 38 is
shown in the approximate center of the strip 12 extending
from the bend line 26 towards the first flange 22.
FIG 4 illustrates one example of an electrical box 40
with sides 42 and a back 44. Two slots 45 are located in
the back surface 44 adjaoent to one edge of a side 42 and
this is the side upon which the bracket 10 is to be
mounted. FIG 5 illustrates a bracket 10 holding an
; electrical box 40 between two wall boards 46. One side of
the box is attached to a steel stud 47 by a stud strap 48
attached to the box 40 which wraps around the stud 47 and
positions the box 40. Other types of attachment devices
such as screws and the like may be used. In this
embodiment, the stud 47 is 3 5/8 inches deep. The box 40 is
provided in the recessed position with a box cover 49
positioned over the open electrical box 40. To install a
bracket 10 to a box 40, the pair of locking tongues 30
may be prebent at right angles or are bent in the field
either by a pair of pliers or other suitable means with the
ends of the tongues 30 placed in the slots 45 in the back
surface 44 of the box 40. The two tab portions 14 which
also may be prebent to about 90 as shown in FIG 3, are
then bent into a hook form as shown in FIG 5 over the edge
of the box side so that the bracket 10 is attached to the
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box 40 by means of the locking tongues 30 and the hook
portion 14 of the two tabs. This is a positive location
'~ and the bracket 10 can only be removed by bending the two
hook portions 14 straight. Thus there is no possibility
for the bracket 10 separating from the box 40.
FIG 6 illustrates another installation of a smaller
electrical box 40 in a thinner wall structure. The pair of
locking tongues 32 are bent and placed in slots 45 in the
back surface 44 of the electrical box 40. The stud 47 is
2 1/2 inches deep and, therefore, the strip 12 is bent on
the bend line 26 as shown in FIG 3 so ~hat the bent portion
of the strip forms the flange to rest against the inside
surface of the wall board 46.
It is preferred that the bracket 10 is pressed out of
sheet steel to produce the bracket illustrated in FIGS 1, 2
; and 3 ready for installation.
Various changes may be made to the embodiments
described herein without departing from the scope of the
present invention which is limited only by the following
claims.
