Improved Electrical Wiring Box Assembly
Field of Invention
[001] The present invention relates to electrical wiring boxes. More
particularly, the present invention relates to an improved electrical
wiring box assembly which provides adjustable fitting for top plate.
Background of the invention
(0021 Electrical wiring connections being made are required to be
placed safely, such that they do not create an electrical hazard. Further,
it is desirable that the wiring connections are resistant to dirt and are
aesthetically pleasing. Wiring boxes are utilized for this purpose so
that connections and instruments are placed safely in a desired
manner.
[003] Such placement of connections therefore require a base and a
top. The base is the electrical wiring box. Top plate is used on the
surface which can be designed to hold various type of electrical
fittings on it such as switches, power points, sockets, single phase
starters, circuit breakers etc.
[004] A wiring box for electrical fittings is typically used either on
the surface of a wall or is inserted and fixed inside the wall. When
being fixed inside the wall, a cavity is created in the wall
corresponding to the size of the wiring box which needs to placed
therein.
e
[OOS] Wiring boxes are therefore the enclosures with which
wiring connections are placed and typically hidden w i t h the wall
cavity or recess. As explained, such boxes may be placed on the
surface of the wall also, where it is not possible to create a recess in
the wall or otherwise if so desired.
(0061 Electrical wiring boxes currently available are typically made
of metal. Prior art is available providing for electrical boxes made of
other materials such as PVC/plastic/polycarbonate. Electrical wiring
boxes made of plastic have some inherent advantages such as being
rust resistant, being shock proof etc. Yet plastic wiring boxes have not
been made available on a large scale because of the following reasons:
1) moulding a plastic electrical wiring box is difficult;
2) cost is relatively hlgh; and
3) structural stability and strength issues.
[007] Generally, wiring boxes are placed inside the walls at the time
of construction of the wall however they can be placed at a later stage
as well which would require a difficult process of breaking the wall to
create the cavity or recess. In such cases it is possible that such cavity
may not properly match with the size of the wiring box
[OOS] Some of structural issues faced by plastic electrical wiring
boxes are:
1) they may not hold fmly against the cement 1 mortar of the wall;
2) problem of breakage of the side wall of the box when tightening the
top plate screws;
3) problem of breakage of screw cavity when tightening the top plate
to the base;
4) fomation/moulding of breakable knockout ports; and
5) unevenlimproper threads for receiving the screws.
[009] Additionally, a problem faced by electrical wiring boxes
whether made of plastic or metal is that if the cavity / recess in the
wall is not sized properly, which is not very unusual, the top plate will
not fit properly or evenly on the box. Ths would give an uneven look
and is aesthetically not pleasing apart from the problem of dust and
insects going inside the box fiom the gap available. An improperly
fitted top plate could also be a shock hazard.
[OlO] In light of the above-mentioned disadvantages, there is a need
for an electrical wiring box whlch would provide high strength, long
life, resistance to shock, and most importantly an adjustable system
for installing the top plate which would not require the wall to be cut
or broken for the box to be reinstalled neither would one have to look
at skewed or slanted electrical fittings which are aesthetically not
pleasing apart from the fact that they could be fire and shock hazard.
Summary of the invention
[Oll] An improved electrical wiring box is provided. In various
@ embodiments of the present invention, the electrical wiring box has
improved configurations for mounting inside the recess of the wall
and provides an adjustable system for fixing of top plate over the
wiring box. Due to adjustable top plate mounting system, wiring box
does not require to be broken out of the cemented wall or reinstalled in
case the box has not been installed at a right angle. Ths prevents
leaving any gap or having a slanted top plate which could be a fire and
shock hazard.
[012] The present invention utilizes a sliding arrangement
comprising of a rail type flange, a support bar, a plastic insert with a
metal nut moulded inside the insert. The plastic insert rests on the rail
type flange and is held in its place by the support bar while still being
movable over the sliding arrangement.
[013] The top plate which acts as a flame for mounting the
electrical termination devices such as switches, sockets, voice and data
connectors etc. is tightened over the electrical wiring box using screws
which are received by the metal nut 1 threading moulded inside the
plastic insert.
[014] The moveable insert over the rail type flange is used to adjust
fixing of the top plate over the wiring box. In the event the wiring box
has not been mounted at a right angle in the recess of the wall, the
inserts can be sled up or down over the rail type flange at the time of
tightening of the top plate screws so that the top plate is mounted
perfectly over the box in spite of the wrong installation of the box
itself. This prevents using the option of breaking the wall to take the
box out to reinstall it properly or otherwise having the electrical
termination equipments being installed in a slanted manner over the
top plate, leaving a gap between the plate and the box which could be
possible fire and shock hazard.
[015] The present invention also comprises of extensions on the
sides of base plate of the wiring box which can hold the box fmly in
place while being mounted inside the cavity I recess of the wall by
cement / mortar or any other material.
Brief description of accompanying drawings
(0161 Fig. 1 provides a perspective view of the improved electrical
wiring box
[017] Fig. 2 shows the plastic insert in various views namely:
Fig 2(a): Perspective view of the insert
Fig 2(b): Side view of the insert showing thicker top portion and
projection at the bottom of the lower portion corresponding with
the support bar of the wiring box
Fig 2(c): Top view of the insert showing the metal nut /
threadmg moulded inside the insert
Fig 2(d): Bottom view of the insert
[018] Fig. 3 shows the section 1 side view of the wiring box
0 [019] Fig. 4 shows the top view of the wiring box as described
Detailed description of the invention
[020] The following disclosure is provided in order to enable a
person having ordinary skill in the art to practice the invention.
Exemplary embodiments are provided only for illustrative purposes
and various modifications will be readily apparent to persons skilled
in the art. The general principles defined herein may be applied to
other embodiments and applications without departing fiom the spirit
and scope of the invention. Also, the terminology and phraseology
used is for the purpose of describing exemplary embodiments and
should not be considered limiting. Thus, the present invention is to be
accorded the widest scope encompassing numerous alternatives,
modifications and equivalents consistent with the principles and
features disclosed. For purpose of clarity, details relating to technical
material that is known in the technical fields related to the invention
have not been described in detail so as not to unnecessarily obscure
the present invention.
10211 The present invention would now be discussed in context of
embodiments as illustrated in the accompanying drawings.
[022] The present invention is an improved electical wiring box 11
whch is utilized as the base for the top plate, housing one or more of
electrical fittings 1 electrical termination devices such as switches,
sockets, power points, circuit breakers etc. The present invention in its
0 different configurations can also be utilized concealed within the floor
in industrial settings for foot initiated operations.
[023] Referring to Fig 1, an improved electrical wiring box 11
formed in accordance with the present invention is shown. The body
of the electrical wiring box is similar to conventional wiring boxes
used for electrical fittings and installations. The wiring box shown in
Fig 1 is rectangular shaped having a base 17 and four side walls 18,
however any shape box may be used.
[024] The wiring box 11 is preferably moulded fiom plastic
however a metal body structure may also be utilized by spot welding
sheet metal pieces together in a conventional manner known in the
industry. A plastic moulded box has some inherent advantages,
primarily, the plastic body provides more durability and long life to
the box, the body is rust proof and shock proof.
(0251 In an embodiment of the invention, the body of the electrical
wiring box 11 can be moulded out of materials such as U-PVC, Nylon,
Polycarbonate, Noryl or similar material which would provide to the
electrical wiring box 11 the quality of being flame retardant.
10261 The four side walls 18 of the wiring box 11 define a fiont
opening whch will face outwardly fiom the wall or floor surface
when the box is installed. The wiring box 11 shown in Fig 1 is adapted
for mounting electrical fixtures, such as a switch and / or an electrical
socket / receptacles.
0
[027] In an embodiment of the invention, the electrical wiring box
11 may be employed in any configuration to accommodate a wide
variety of electric termination components including voice and data
connectors.
[028] In another embodiment of the invention, the wiring box 11
includes knock-out ports 12 for receiving electrical wires, cables and
conduits through any side of the box 11. The box 11 is placed within
the recess of the wall and one or more wires, cables or conduits are
then fed througlr the knock-out ports 12 of the box and are connected
to the box 11 by conventional electric cable connectors.
[029] In yet another embodiment of the invention, the knock-out
ports 12 are slightly thinner than the rest of the electrical wiring box
body. This configuration would render the knock-out ports 12 more
easily shearable from the wiring box 11.
[030] In an embodiment of the invention, the wiring box includes a
sliding arrangement 19 comprising of rail type adjustment flanges 13
on at least two opposing side walls 18 extending inwardly fiom the
inside surface of the side walls 18 forming a closed rectangular loop.
Synthetic fiber / plastic insert 14 rests on the rail type adjustment
flange 13. Inserts include metal nut 15 with internal screw threading
moulded within the inserts 14 for receiving the screws of the top
plate / switch plate.
@ [031] Figure 2 shows the insert 14 in various views. Referring to
Fig. 2(b), the insert 14 has an inverted L shape with the top portion 21
slightly thicker than the lower portion 22 since the metal nut 15 is
moulded inside this top portion 21. At the bottom of the lower portion
22 a projection 1 extension 23 is present which corresponds with the
support bar 31 of the wiring box. The corresponding projections of the
insert 14 and the support bar 31 on the wiring box 11 keep the insert
14 moveable yet fixed over the sliding arrangement 19.
[032] In an embodiment of the invention, the metal nut 15 moulded
inside the plastic insert 14 is of brass or any other similar metal whch
provides strength and anti-rust properties to the metal screw threading.
10331 The plastic insert 14 with the moulded metal nut 15 can be
easily replaced if in case the insert breaks while tightening the top
plate to the wiring box assembly 11. Plastics with high tensile strength
is preferred for moulding of the insert 14 such as Nylon 6 or similar
material which has high strength, stability and rigidity. Anti rust metal
nut moulded inside the high tensile plastic of the insert 14 makes sure
that the insert 14 would be able to bear the load of tightening the
screw with a screw driver. The insert 14 can be pushed in place over
the sliding arrangement 19 and the insert then stays in place over the
flange 13. This way the entire unit would not require to be replaced
due to breakage of the plastic insert 14 for any reason.
[034] The insert 14 rests on the rail type flange 13 of the sliding
arrangement 19. The rail type flange 13 is moulded continuously with
0 the side walls 18. In other words, there is no joint between the side
wall 18 of the box body 11 and the rail type flange 13 and because of
that any pressure put on insert 14 while tightening the screws is
dispersed to the side walls 18 through the rail type flange 13. Thls
mechanism prevents the insert 14 from breakage due to pressure
applied by a screw driver.
[035] In an embodiment of the invention, a protective cover is
provided over the inserts 14 on the sliding arrangement 19 to prevent
concrete I cement 1 mortar or any other building material from
entering the threading of the moulded metal nut 15 during the
preparation of the wall. Once the wall is complete, the protective
cover is removed and the insert 14 can now be adjusted to bring the
top plate in level with the upper surface of the finished wall.
[036] In another embodiment of the invention, the base plate 17 of
the wiring box 11 is provided with at least two millimetre extensions
16 on at least two opposing sides of the base plate 17 and preferably
all sides. The extensions help the box 11 to be held firmly in position
and prevents the box 11 from moving once it is placed w i t h the
recess of the wall and covered on the sides by pouring cement /
mortar.
[037] Sitting on top of the electrical wiring box 11 is the top plate
whch acts as a fiame for the electrical fittings. Such top plates are
manufactured in standard sizes by companies producing electrical
termination devices such as switches, sockets, data and voice
0 connectors etc. The top plate is provided with through holes which
receive the screws tightened on to the moulded nuts 15 on the inserts
14 of the wiring box 11. The electrical wiring box 11 of the present
invention can be manufactured in various sizes so as to be compatible
with the standard sizes of the top plates 1 cover plates of different
manufacturers.
(0381 The top plate is tightened on to the electrical wiring box 11
using screws whch are received by the metal nut 15 moulded within
the plastic inserts 14. Electrical fittings and devices can then be
mounted within the frame of the top plate using screws whlch are
received by the top plate. The sides of the top plate are then covered
by a cover plate to prevent dirt fiom entering the box from through
holes. Such cover plates are also manufactured by companies
producing electrical termination devices in corresponding standard
sizes.
[039] In an exemplary embodiment of the invention, if the top plate
does not sit properly on the wiring box 11 due to slant arrangement or
improper fixing of the wiring box 11 within the wall, the inserts 14
can be appropriately sled up or down on the sliding arrangement 19
before tightening the screws over the inserts 14 to adjust the top plate
to fit properly on the wiring box 11 such that it is positioned parallely
on the surface without leaving any gap and 1 or resting in a slanted
position.
[040] Having thus described a few particular embodiments of the
0 invention, various alterations, modifications, and improvements will
readily occur to those skilled in the art. Such alteration, modifications,
and improvements as are made obvious by this disclosure are intended
to be part of this description though not expressly stated herein, and
are intended to be within the spirit and scope of the invention.
Accordingly, the foregoing description is by way of example only, and
not limiting. The invention is limited only as defined in the following
claims.

We claim:
1. An improved electrical wiring box assembly comprising:
a plastic or metal box having a base plate and four side walls
defining the front opening;
one or more knock-out ports on at least one side wall of the
box for receiving cables, wires or conduits; and
a sliding arrangement on at least two opposing side walls,
below the fi-ont opening of the box, wherein the sliding arrangement is
formed so as to provide adjustable fitting for fixing a top plate.over
the box.
2. The wiring box assembly as claimed in claim 1 wherein the sliding
arrangement comprises:
a rail type flange formed continuously (joint-less) with the
side wall of the box body;
a plastic insert resting on the rail type flange;
a metal nut moulded inside the upper portion of the plastic
insert with internal screw threading; and
a support bar moulded in the side wall of box below the rail
type flange, keeping the insert enclosed over the rail type flange and
movable over the sliding arrangement.
3. The wiring box assembly as claimed in claim 1 wherein the base
plate of the box body has extensions of at least two millimetre on at
least two opposing sides of the box, further wherein the extensions are
provided to hold the wiring box fmly in position during placement of
the box inside a recess.
4. The wiring box assembly as claimed in claim 1 wherein the top of
the insert is covered by a removable protective cover, fwther wherein
the protective cover is provided to prevent extraneous materials such
as dirt or cement fiom entering and damaging the internal screw
threading of the metal nut moulded inside the insert.