GB2555081A

GB2555081A - Protective cover plate and dry wall board marker

Info

Publication number: GB2555081A
Application number: GB1613760.6A
Authority: GB
Inventors: Harris Dean
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-08-10
Filing date: 2016-08-10
Publication date: 2018-04-25

Abstract

A protective cover plate which fits into the open side of an electrical wall outlet back box, in order to allow plastering without exposing the contents of the box to damage, has a flat rectangular surface and four upstanding side walls at an angle of 90° or more. A marker plate which attaches to the flat surface of the said cover plate contains upward pointing spikes (15, Fig 10) so that wall board which is placed over the said outlet box is marked by the said spikes for the purpose of locating the cut out position. An alternative cover plate is resilient and is held by a friction fit.

Description

(71) Applicant(s):

Dean Harris

Iverlay Walk, STOURBRIDGE, West Midlands, DY9 0YJ, United Kingdom (72) Inventor(s):

Dean Harris (51) INT CL:

H02G 3/12 (2006.01) E04F 21/04 (2006.01) (56) Documents Cited:

GB 2444260 A GB 1344590 A

DE 007335836 U DE 003528965 A1

DE 002036320 A1 (58) Field of Search:

INT CL E04F, H02G

Other: Online: WPI, EPODOC (74) Agent and/or Address for Service:

Black Country Inventors Club 31 Ambrose Crescent, KINGSWINFORD, West Midlands, DY6 7RE, United Kingdom (54) Title of the Invention: Protective cover plate and dry wall board marker

Abstract Title: Protective cover plate and marker plate for use when plastering (57) A protective cover plate which fits into the open side of an electrical wall outlet back box, in order to allow plastering without exposing the contents of the box to damage, has a flat rectangular surface and four upstanding side walls at an angle of 90° or more. A marker plate which attaches to the flat surface of the said cover plate contains upward pointing spikes (15, Fig 10) so that wall board which is placed over the said outlet box is marked by the said spikes for the purpose of locating the cut out position. An alternative cover plate is resilient and is held by a friction fit.

Figure 7

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Figure 7

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Figure 9

Figure 10

PROTECTIVE COVER PLATE AND DRYWALL BOARD MARKER

The present invention relates to apparatus for covering the front open side of an electrical wall outlet box before a finishing plaster coating is applied to the wall upon which the box is mounted. Included in the present invention is a marker plate which is used in conjunction with the Protective Cover Plate to assist in establishing the exact location of the said electrical wall box when fitting dry wall lining board.

This invention is more particularly for use by those employed that part of the electrical installation industry which is closely associated with the building trade in situations where plastering and electrical fitting are taking place at the same location.

Where building work is taking place, either in new build or refurbishment situations, electrical installation work is usually carried out in stages. Initially during a stage known as “first fix” the task of installing electrical cables and their associated wall outlet boxes is carried out. These wall outlet boxes are also known as knockout boxes or KO boxes.

At the first fix stage it is frequently the case that the walls in the building are not finished. That is to say that they are not plastered or dry wall lining board has not yet been fitted and skimmed with finishing plaster. At this stage the electrical cables are installed, the unfinished walls are covered with suitable cable protective means, the wall socket outlet boxes and switch outlet boxes are fitted and the cables are fed into the wall boxes and left unterminated.

It is usual that when the first fix is completed, the walls are then finished with base and top coats of plaster or lined with dry wall boarding and then finished with a plaster skim.

There then follows a second stage known as “second fix” and this is where the electrician connects the electrical accessories such as wall sockets and switch plates to the wires which were left unconnected during first fix. The electrical installation is then powered up and tested for electrical performance and insulation resistance.

Various problems frequently occur following first fix and before second fix.

These problems arise from the work carried out by operatives employed to apply the finish to the walls. Plasterers frequently fill the wall outlet boxes with plaster since they are simply concerned with finishing the wall and not the electrics. They often damage the insulation of the electrical cables with their finishing tools. They can also cause damage to the outlet box and cables when fitting a dry wall lining board since it is difficult for them to judge the exact location of an outlet box when covering it with dry wall lining board. Certain pressure is often applied to cause an impression of the box in the board so then a suitable aperture may be cut in the board or holes are made in the board to allow access to the wall socket causing damage to the cables in the box behind the board.

When the electrician arrives to carry out second fix the plaster overfill is easily seen but it takes time to remove this plaster without causing further damage to the cables. Damage to the cabled insulation is less easily seen and may often be found only when carrying out insulation tests. Rectification work then has to be carried out and new cables may have to be installed.

The present invention is intended to provide a solution to the damage occurring between first and second fix by sealing the wall box in such a way that the 10 plastering can be carried out over the box. This makes the plasterer’s job easier since there is no obstacle to overcome, no damage can occur to the cables and the plasterer can then simply skim a flat wall. Because of the colouration, the box is easily visible under the drying plaster and a simple tap will crack the plaster around the wall box and the protective plate can then be removed exposing the clean wall box and preserving the integrity of the cables.

Examples of typical prior art are : US2008/0047731 which is a plate intended as a marker plate to enable the installer of drywall boarding to locate the correct position of the wall box. This plate functions well as a marker plate but not as a protective cover plate as presented in the present invention.

GB2457520 describes a safety shield for a wall box. This invention attempts to provide a solution to the problem described herein but does not facilitate the plastering in the same way as does the present invention.

In this specification the terms, electrical outlet box, electrical wall outlet box, switch outlet box, box, wall box, knockout box and KO box all have the same meaning.

According to a first aspect of the invention there is provided a protective cover plate, intended for mounting within an electrical wall knock out box. The shape of the said plate resembles a shallow rectangular tray which has a base and four raised sides. Each of the four sides is set at an angle of ninety degrees or an angle greater than ninety degrees with respect to the base to which they are attached.

The said plate has holes provided at the edge of the base of the tray which correspond with the fixing screw positions provided in the knock out box to which the plate is intended to be attached. These are the screw provisions which normally accept fixing screws which are used to secure the wall switch plate or socket which will eventually be attached to the knock out box.

In a preferred embodiment the said plate is made from a resilient material so that when the sides are set at an angle greater than ninety degrees to the base, the long edges of the sides which are not attached to the base contact the sides of the receiving knock out box to make a friction fit.

In a further preferred embodiment the corners of the said plate are cut away so as to create 4 further edges to the base to which nothing is attached. These four further edges are in addition to the four edges to which the sides are attached.

In a further embodiment the said plate is a flat plate made from a resilient material which is for example, foam rubber or plastic and has no raised sides. In this embodiment the plate is designed to fit into the knock out box and remain in place either by being a friction fit or is secured by suitable means which can include fixing screws.

The depth of the wall box which is to receive the cover plate is irrelevant. There are various depths depending on the accessory to be eventually installed. For 10 example light switches require a shallow box compared to socket outlets, but the present invention cover plate fit is exactly the same for all depths of wall box.

In addition, the width of the wall box can vary beyond the examples given in this specification. For example, for 3 or 4 gang switches or sockets the present invention is simply produced in extended width to fit such boxes.

In a second aspect of the invention there is provided a flat rectangular marker plate which is intended to be inserted on top of the aforementioned cover plate.

This flat rectangular marker plate is equipped with one or more marker spikes and in a preferred version there is one at each corner so that when in position on top of the said protective plate and a dry wall lining board is placed over the plate, four marks are made by the said spikes on the said board indicating the position of the knock out box relative to the dry wall board. This marker plate is secured into position by any suitable means including magnetic means.

The invention will now be more particularly described with reference to the drawings in which: Figure 1. Is a typical wall box or knock out box

Figure 2. Is a two gang wall box

Figure 3. show a typical embodiment of the present invention

Figure 4 Is an expanded view of the bottom right hand corner of figure 3

Figure 5. is a cross section of the plate at point AA in Figure 3

Figure 6. Is identical to figure 3 but extended to fit a wider wall box

Figure 7 Shows a wall box fitted with a cover plate in accordance with the present invention.

Figure 8 shows how the wall box would appear when fitted with a plate in accordance with the present invention and after dry wall boarding has been added but before the final plaster skim.

Figure 9 Illustrates the marker plate

Figure 10 Isa cross section of the marker plate in Figure 9

Referring now to figure 1 this illustrates a typical commercial wall or knock out box. This is a hollow box open on one side so that side edges 1 are exposed.

The box has knock out holes 2, for cable entry, fixing holes 5 and accessory fixing screw points 3,4, and 6. Point 3 is adjustable. The only visible parts of this box once it is installed are the inside and the edges 1. Figure 2 is a similar box in a two or three gang version. The depth of the box will vary according to the requirements of the accessory which it is intended to receive.

Figure 3 is an illustration of the invention consisting of a flat plate with a base 7 and four sides 8a to 8d. There are four side walls or edges 8a,b,c,d, which are folded as illustrated in figure 5. The angle C (figure5) between the edge of the each said side wall which is attached to the base and the base of the plate is 90 degrees or in a preferred version is greater than 90 degrees. The distance between the longest edge of each side wall, which edge is attached to the base of the plate and the second longest edge 9, as illustrated is approximately equivalent to the distance between the surface of the fixing lug 6 and the edge 1 of the box (in figures 1 and 2) less the thickness of the plate. Provision is made in the base of the plate for fixing screws to pass through the plate at 12 which screws would be attached to lugs 3 and 4 in figure 1.

Figure 4 shows an expanded view of the corners. In a preferred embodiment the corner of the base is cut away providing a short edge 10 of any suitable length at each corner. The side walls 8 may also be further trimmed along their shortest sides 11, so that Angles B which can be 90 degrees may also be less than 90 degrees.

For the sake of clarity, figure 5 which has been referred to before in this specification is a cross sectional view of the plate shown in figure 3 taken at point AA. Also Figure 6 shows a plate with all the same features and functions of the plate shown in figure 3 but is extended for use in a two or three gang wall box.

When the cover plate is mounted within the wall box it will appear as illustrated in figure 7 and when the walls finishing is applied the sides and back of the box will no longer be visible as illustrated in figure 8.

Figure 9 shows a second aspect of the invention which is a marker plate intended for use in conjunction with the cover plate. In use this plate is placed on top of the cover plate. This marker plate is cut away at 14 to avoid the fixing screws securing the cover plate. A spike or spikes 15, are attached to the surface of the marker plate so that when wall board is placed over the box marks are made on the wall board which indicate where the wall box is located and a suitable hole may then be cut in the wall board. Removable fixing of the marker plate to the cover plate is by any suitable means, but in a preferred embodiment, magnetic attachment means 16, is employed and this may be any suitable number of magnets. This marker plate is essentially flat and that is illustrated in the cross sectional drawing which is figure 10.

Further embodiments are envisaged which are not illustrated where the cover plate consists of a piece of foam rubber or plastic which is an interference fit within the wall box and the thickness of the said further embodiment is equal to the distance between the lugs 3 and 4 and 6 and the edge of the wall box 1 as illustrated in figure 1. This embodiment can simply be placed into the wall box, it can be secured by any suitable means but in a preferred embodiment the natural resilience of the material will keep the plate in place.

Claims

5 1. A protective cover plate intended in use to fit into to the open side of an electrical wall knockout box the said plate consisting of a flat rectangular surface with four raised side walls which side walls are in use set at an angle of 90 degrees or greater than 90 degrees to the exposed side of the flat rectangular surface of the said cover plate.
2. A protective cover plate as claimed in claim 1 which is made from a suitable resilient material so that in use when the said raised sides are set at an angle of more than 90 degrees to the exposed flat rectangular surface of the said flat plaate the long edges of the said sides which are

15 not attached to the flat plate will contact the sides of the said knockout box which is receiving the cover plate.
3. A protective cover plate as claimed in claim 1 or 2 with provision for fixing screws by mean of holes in the flat surface of the cover plate which

20 correspond to elements in the said knockout box intended to receive fixing screws.
4. A cover place as described in any previous claim in which the corners of the flat rectangular surface of the plate are cut away so as to create 4 25 further edges to the said plate in addition to the 4 edges to which the said sides are attached.

5. A flat rectangular marker plate for use with a cover plate as described in any previous claim the said marker plate consisting of a flat rectangular
5 plate intended in use to be places against the exposed surface of the said cover plate with one or more spikes attached to the said marker plate which spikes in use extend from the exposed surface of the said marker plate

10
6. A marker plate as described in claim 5 which in use is retained in place by any suitable means including magnetic means.
7. A cover place as made from a resilient material which is a friction fit into the receiving knockout box which plate may have provision for fixing

15 screws.

Intellectual

Property

Office

Application No: GB1613760.6 Examiner: Paul Nicholls