Electrical receptacle box assembly

An electrical receptacle box assembly including an electrical receptacle box mounted on a wall stud having a relatively thin-walled major side surface prepared with a plurality of vertically spaced apart mounting holes in patterns of two. The electrical receptacle box is equipped with first and second bracket means, each engageable with a corresponding mounting hole. One of the bracket means includes a clip having a plurality of longitudinal fingers. One of the fingers is offset from the others so as to be engageable with a mounting hole in straddling relationship to an edge of the hole. The other fastener includes a linear portion extendible through the opposite mounting hole and connected to a side wall of the electrical receptacle box. The box is quickly and securely engageable with the wall stud preparatory to mounting electrical receptacles and eventual covering with wallboard.

BACKGROUND OF THE INVENTION 
The invention relates to the field of electrical receptacle boxes mountable 
on a generally vertical wall stud of the type having a thin-walled major 
side member, such as a metal wall stud commonly used in building 
construction. 
For considerations of durability, longevity and fire resistance, metal wall 
studs are commonplace in commercial and residential building construction. 
As compared to common wooden wall studs, special problems are presented 
when mounting certain equipment, such as electrical receptacle boxes to 
hold outlets, switches and the like because the metal wall stud is not as 
readily penetrable by common fasteners as is the wooden stud. In the prior 
art, various clips and clamps are used which forcibly engage an edge of 
the stud leaving a bulge when covered by wallboard. Screw fasteners are 
also used but are time consuming and in commercial building construction, 
conservation of time is a relevant factor in containing costs. 
SUMMARY OF THE INVENTION 
The present invention comprises an electrical receptacle box assembly 
including an electrical receptacle box mountable on a wall stud having a 
relatively thin-walled major side surface, such as a metal wall stud. The 
metal wall stud is prepared with a plurality of holes in patterns of two 
which are vertically spaced apart when the wall stud is in an upright 
orientation. The holes are oblong in shape with a horizontal major axis to 
provide elongate mounting edges. 
The electrical receptacle box is equipped with a side wall having 
vertically spaced apart bracket means or fasteners for assembly with first 
and second holes of a hole pattern. One of the fasteners is comprised as a 
clip having a plurality of fingers which straddle one of the edges of a 
mounting hole. The other fastener is comprised as either a prong or tine 
which is insertable through the mounting hole under slight spring 
deflection, or as a tab which receives a self-threading screw which passes 
through the tab and engages the hole edges. The box is quickly and 
securely assembled to the wall stud with a resultant savings of time. 
In those instances where a box is to be assembled on the interior surface 
of the major side wall member of a U-shaped metal wall stud, a spacer or 
extension member is provided. The extension member is mounted between the 
wall stud and the electical receptacle box to space the box outward of the 
stud.

DESCRIPTION OF PREFERRED EMBODIMENTS 
Referring to the drawings, there is shown in FIGS. 1 through 3 an 
electrical receptacle box assembly according to the invention indicated 
generally at 10 and including an electrical receptacle box 11 mounted on a 
generally upright wall stud 12. Wall stud 12 is of the variety having a 
relatively thin-walled major side member 14 with perpendicularly 
orientated end members 15, 16 and relatively short in-turned lips or 
flanges 17, as is characteristic of metal wall studs commonly used in 
building construction. Major side member 14 is prepared with a vertical 
row of linearly aligned mounting holes or openings 19 proximate one edge 
which are spaced apart in hole patterns of two, for purposes which will be 
described. A second row of mounting openings 20 can be provided proximate 
the oposite edge of major side member 14 to increase the versatility of 
the metal wall stud. The openings 19, 20 are oval or oblong with a major 
axis horizontally orientated when the metal wall stud is in the generally 
upright orientation as shown. 
Electrical receptacle box 11 includes a box-like housing formed of side 
walls 22-25 connected in perpendicular orientation and fixed to a back 
wall 26 with an open front. Circular knock-out members 28 can be provided 
to permit access to the interior of the housing by conduit or the like. 
Mounting lugs or members 29 extend inwardly from the wall edges for 
mounting electrical receptacles, such as the socket 30 shown in FIG. 1. 
A side wall 22 of box 11 carries longitudinally spaced apart first and 
second fastening means 32, 33 which engage a pattern of first and second 
holes 19A and 19B to hold the box to the wall stud 12. First fastening 
means 32 includes an outwardly offset shoulder 34 extended outward from 
one end of the side wall 22. A plurality of first, second and third 
fingers 36, 37, 38 are curved to extend longitudinally from the shoulder 
34 directed away from side wall 22. Intermediate resilient second finger 
37 is curved in a direction to be slightly outwardly offset or spaced 
apart from adjacent first and third fingers 36, 38 forming a wedge-shaped 
mouth or gap 40 (see FIG. 2) of sufficient maximum width to closely engage 
the edge of a mounting hole 19A as best seen in FIG. 3. As shown, inner 
finger 36 can extend the width of the side wall. The outer edge of the 
hole 19A is wedged in the diverging inner portion of the gap 40. The width 
of the intermediate finger 37 corresponds to, but is slightly less than, 
the width of the oblong hole 19. Gap 40 engages a relatively linear 
portion of the hole to inhibit rocking motion of the box 11. 
Opposite fastening means 33 includes linear means extended in perpendicular 
relationship to both the surface of the major side member of the wall stud 
and the major axis of the mounting holes for engagement with an edge of 
the second mounting hole 19B. An arm 42 extends longitudinally from the 
side wall 22 to a reverse curve spring loop 43, which terminates in a 
linear U-shaped tine or prong 44 extended in a direction perpendicular to 
the longitudinal axis of the wall stud 12 and the major axis of the 
mounting hole 19. Prong 44 is formed from the flat end of arm 42 and 
includes a flat base 46 and upwardly turned side walls 47. Longitudinally 
facing notches 48 are formed in the side walls 47 near the inner end of 
prong 44 and are of sufficient width for engagement of the edge of a 
mounting hole 19. The side walls 47 converge forwardly to form a tapered 
end for ease of insertion into a mounting hole. The width of base 46 
combined with the walls 47 corresponds to, but is slightly less than, the 
width of a mounting hole 19 along the major axis thereof. 
Laterally opposite fastening means 33 on the side wall 22 is an L-shaped 
stop member 50 comprised of a longitudinal member extended from the side 
wall 22 and an outwardly extended member 51 positioned to abut the surface 
of the major side member 14 of wall stud 12 when the prong 44 is 
positioned in one of the mounting holes. Stop member 50 inhibits rocking 
action of box 11 about a vertical axis. 
In use of the electrical receptacle box assembly of the invention, metal 
wall stud 12 is placed in a generally upright orientation in the usual 
process of building construction and has a plurality of hole patterns 
formed by the mounting holes 19. The builder selects a pair of mounting 
holes 19 according to the desired location of an electrical receptacle box 
and then mounts the box 11 accordingly. The box is mounted by inserting 
the intermediate finger 37 of the lower bracket means 32 through a 
mounting hole 19 whereby the edge of the hole is engaged in the gap 40. 
Prong 44 is then inserted in the corresponding opposite hole of the hole 
pattern. Spring loop 43 permits a degree of deflection of the prong 44 as 
it is inserted in a mounting hole 19. Prong 44 is inserted in the hole 19 
until the edge of the hole snaps into place in the notches 48 which engage 
the relatively linear edge portion of the mounting hole 19 and inhibit 
rocking motion. Extended member 51 mounted on stop member 50 further 
inhibits rocking motion whereby the box 11 is securely mounted to the wall 
stud 12 for mounting of receptacles 30 and the like and eventual covering 
by a suitable wallboard. 
Referring to FIGS. 4 through 7, there is shown an electrical receptacle box 
assembly according to another form of the invention indicated generally at 
54 and including an electrical receptacle box 55 mounted on a generally 
upright wall stud 56. Wall stud 56 is of the variety having a relatively 
thin-walled major side member 58 with perpendicularly orientated end 
members 59, 60 and relatively short, inwardly turned lips or flanges 61. 
Major side member 58 is prepared with a vertical row of linearly aligned 
mounting holes or openings 63 which are spaced apart in patterns of two 
for purposes of mounting the electrical receptacle box. A second row of 
mounting openings 64 can be provided along the opposite edge of the major 
side member 58. The openings 63, 64 are oval or oblong with a major axis 
horizontally orientated when the metal wall stud is in the generally 
upright orientation as shown. 
Electrical receptacle box 55 includes a box-like housing formed of side 
walls 66-69 connected in perpendicular orientation and fixed to a back 
wall 70 with an open front. Mounting lugs or members 72 are provided 
extending inwardly from the wall edges for mounting the electrical 
receptacles, such as the outlet socket 73 shown in FIG. 4. 
A side wall 66 of the box 55 carries first and second fastening means 75, 
76 to mount the electrical receptacle box to a pair of mounting holes. The 
first fastening means 75 is like that shown in FIG. 1 through 3 and 
includes an offset shoulder 78 angularly extended away from the side wall 
66. First, second and third fingers 79, 80 and 81 extend longitudinally 
from the shoulder 78. Intermediate second finger 80 is slightly offset 
from adjacent fingers 79, 81 forming a wedge-shaped gap 83 having a 
maximum width of sufficient dimension to closely engage the edge of a 
mounting hole. As shown in FIG. 6, the lower edge of a mounting hole 63 is 
engaged in the wedge 83 straddled by the intermediate finger 80 and the 
adjacent fingers 79, 81. The diverging configuration of the gap 83 wedges 
the upper edge of the mounting hole in place. The portion of the hole edge 
engaged in gap 83 is relatively linear resulting in a stable engagement. 
Second bracket means 76 includes a second shoulder 86 longitudinally 
extended from the side wall 66 with an offset portion terminating in a 
longitudinal flat tab or plate 86. Plate 86 has a mounting hole 88 which 
aligns with one of the mounting holes 63 on the wall stud 56 when the 
bracket means 75 is engaged in a corresponding opposite mounting hole. A 
linear fastener comprised as a screw 89 having a pointed shank 90 is 
threaded through the mounting hole 88 and through the mounting hole 63 on 
the wall stud 56. Shank 90 has a diameter near the head of screw 89 of 
sufficient width that the threads engage the edges of the mounting hole 63 
to hold the mounting plate 86 in place and secure the electrical 
receptacle box 55. 
In use of the assembly 54, one of the mounting holes 63 of a suitable 
pattern is selected and the intermediate finger 80 is placed through the 
hole, such that the edge of the hole is engaged in the wedge 83 defined 
between the intermediate finger 80 and adjacent side fingers 79, 81. The 
box is rotated to the point where the plate 86 comes into contact with the 
wall member 58 of the metal wall stud 56. Screw 89 is threaded through the 
opening 88 and mounting plate 86 and through the mounting hole 63 on the 
wall stud 56. The outer diameter of the threads of the screw are such that 
they engage the edge portions of the hole to hold the box in assembled 
relationship to the wall stud. Electrical receptacles are then mounted to 
the box preparatory to installation of wallboard. 
Occasionally, it is necessary or convenient to mount the electrical 
receptacle box on the interior of the metal wall stud or the surface of 
major side member 14 opposite that shown in FIG. 1. A spacer or extension 
member 93 is provided for such purpose. FIG. 11 shows the electrical 
receptacle box assembly components of FIG. 1 in assembly view, along with 
an extension member 93 and with metal wall stud 12 in reverse or turned 
around orientation in order to expose the inner surface of major side 
member 14. 
As shown in FIG. 7, extension member 93 is generally channel-shaped having 
a flat, thin-walled mounting surface or face 94 with a pair of oblong 
mounting holes 95 vertically spaced apart according to the mounting hole 
pattern of wall stud 12. Mounting holes 95 are positioned to accept the 
fastening means 32, 33 of electrical receptacle box 11 when extension 
member 93 is mounted on wall stud 12 with the face 94 in parallel 
relationship to the major side member 14. End legs 96, 97 extend in 
perpendicular relationship from the ends of the mounting face 94 toward 
the major side member 14 and are of a length approximating the depth of 
wall stud 12 between the flanges 17 and inner surface of major side member 
14. 
End legs 96, 97 carry first and second fastening means 98, 99 for mounting 
to mounting holes 20 located on major side member 14. First fastening 
means includes first, second and third spaced-apart fingers 101, 102, and 
103, longitudinally extended from the inner end of the first end leg 96. 
The fingers extend longitudinally inward with respect to the extension 
member 93, or upward as shown in FIG. 7. Intermediate finger 102 is 
outwardly offset with respect to adjacent fingers 101, 103 forming a gap 
105 of a width for engagement with a relatively linear portion of one of 
the mounting holes 20 on major side member 14 of wall stud 12. 
Second fastening means 99 includes a shoulder 106 curved inwardly from the 
end of second leg 97 forming a horizontal spring loop 107. A linear prong 
108 extends outward from spring loop 107 in a direction perpendicular to 
the axis of wall stud 12 and the major axis of mounting hole 20. Spring 
loop 107 allows a measure of resilient deflection of prong 108. Prong 108 
has downwardly turned side walls 110 that are outwardly convergent forming 
a tapered tip. Longitudinal notches 111 are formed in side walls 110 
toward an inner end of prong 108 and have a sufficient width for 
engagement of the edge of a mounting hole 20. The distance between the 
first and second fastening means 98, 99 is slightly less than the 
corresponding distance between mounting hole edges of a pair of holes 20 
forming a pattern. The finger 102 of the first fastening means 98 is 
inserted in a mounting hole 20 with the edge resting in the gap 105 as 
earlier described. Under slight spring deflection, prong 108 is inserted 
through the second hole of the pattern and moved inwardly until the 
notches 111 engage the edge of the hole to secure the extension member 93 
in place. Electrical receptacle box 11 is then mounted to the extension 
member 93 as though it were a portion of wall stud 12. The first and 
second fastening means 32, 33 engage the oblong mounting holes 95 located 
on the mounting face 94 to secure the box in place with the opening for 
the box clear of the wall stud 12 and accessible for mounting of 
electrical receptacles and eventual covering by a suitable wallboard. 
While there has been shown and described certain preferred embodiments of 
electrical receptacle boxes according to the invention, it will be 
apparent that deviations and changes can be had from the embodiments shown 
without departing from the scope and spirit of the invention.