NZ780189A - Electrical wall box and cover - Google Patents

Abstract

Disclosed is an electrical device comprising: a base for mounting to a surface; and a cover for covering at least a portion of the base; wherein the cover comprises a first part of a locking mechanism and the base comprises a second part of the locking mechanism which when engaged, lock the cover to the base, and wherein the first part and the second part of the locking mechanism are caused to engage to lock the cover to the base upon connecting the cover to the base. Also disclosed is a cover, a base and a method for using the electrical device. the base, and wherein the first part and the second part of the locking mechanism are caused to engage to lock the cover to the base upon connecting the cover to the base. Also disclosed is a cover, a base and a method for using the electrical device.

Description

ELECTRICAL WALL BOX AND COVER CAL FIELD The present application relates to ical gs, and in some examples, electrical housings for receiving a conduit.

INCORPORATION BY REFERENCE The entire content of each of the following Australian Provisional Patent Applications filed on 25 September 2020: - “Wall Box Cable Connection” No. 2020903469 - “Wall Box With Socket Cover” No. 2020903468 - “Wall Box Conduit Connection System And Method” No. 2020903465 is hereby incorporated by reference.

PRIORITY This application claims priority from lian Provisional Patent Application No 3464 entitled “Electrical Wall Box and Cover” filed on 25 September 2020. The entire content of this Provisional Patent Application is hereby incorporated by reference.

BACKGROUND In the electrical industry, it is often necessary to provide electrical power to one or more components housed within a housing. In such cases, the housing es an aperture through which a conduit carrying electrically-conductive wires can be passed to allow the electrical wires to be connected to the components therein.

A particular example of such a scenario is in the use of mounting blocks to provide a power socket/outlet at a new location. In such situations, the power-carrying wires are provided from a power source such as mains or supply power (e.g. from a wall outlet) encased in a nonconductive conduit, and directed towards a ng block which is an electrical housing which can be mounted to a new surface (e.g. within a cupboard). The conduit is received within the mounting block through an aperture and the wires connected to respective terminals of the socket, before the socket plate is mounted to the mounting block. Many of these wall box arrangements comprise a base and a cover to cover the base. In some nments, the wall box is susceptible to being d or ged by passers by, or moving machinery, or in some cases, where the wall box is mounted underneath a horizontal surface, the cover may fall off.

This may expose some of the electrical wires within the box and may present a safety .

The arrangements disclosed address at least one of the antages of current arrangements.

SUMMARY According to a first aspect, there is provided an electrical device comprising: a base for mounting to a surface; and a cover for covering at least a portion of the base; n the cover comprises a first part of a g mechanism and the base comprises a second part of the locking mechanism which when engaged, lock the cover to the base, and wherein the first part and the second part of the g mechanism are caused to engage to lock the cover to the base upon connecting the cover to the base.

According to a second aspect, there is provided a cover for connection to a base of an electrical device, the cover comprising a first part of a locking mechanism for engaging with a second part of the locking mechanism, the second part ed on the base and wherein the cover is deformable to allow movement of the first part relative to the second part of the locking mechanism when the two parts are engaged.

According to a third aspect, there is provided a base for connection to a cover of the second aspect, the base comprising a second part of a locking mechanism, the second part comprising: a channel for receiving the first part; and at least one protrusion extending over at least a part of the channel, for engaging with the first part of the locking mechanism.

According to a fourth aspect, there is provided an electrical device comprising: a base for mounting to a surface; and a cover for covering at least a portion of the base; wherein the cover ses a first part of a locking mechanism and the base comprises a second part of the locking mechanism which when d, lock the cover to the base, and wherein the first part and the second part of the locking mechanism are caused to disengage to unlock the cover from the base upon deforming the cover or the base. ing to a fifth aspect, there is provided a method of ing a cover from a base of an electrical device, the method comprising: deforming the cover to cause a first part of a locking ism to disengage from a second part of the locking mechanism disposed on the base; and sliding the cover from the base.

BRIEF DESCRIPTION OF DRAWINGS Embodiments of the various aspects described herein will be detailed with reference to the accompanying drawings in which: Figure 1 – shows an example of an electrical , such as a wall box, comprising a cover and a base according to some aspects; Figure 2 – shows a side view of the electrical device of Figure 1 with the cover connected to the base; Figure 3 – shows a rear view of the electrical device of Figure 2 showing the g mechanism; Figure 4A – shows the arrangement of Figure 4A with pressure applied by a user to the sides of the cover; Figure 4B – shows the shows the arrangement of Figure 4A with the top of the cover deforming (raising) due to the pressure applied; Figure 4C - shows a side view of the arrangement of Figure 4B with the locking mechanism parts disengaged to unlock and allow removal of the cover; Figure 5A – shows a front ctive view of a general embodiment of a base unit according to one aspect described herein; Figure 5B – shows a rear view of the base unit of Figure 5A; Figure 6 – shows a side view of an ical system according to an aspect described herein; Figure 7 – shows an embodiment of a base unit or grid plate and a cover unit or face plate according to an aspect described herein; Figure 8 – shows an example of the base unit or grid plate for Figure 6 and exchangeable cover units or face plates according to an aspect described herein; Figure 9A – shows another example of a cover or face plate that may be used; Figure 9B – shows another example of a base or grid plate that may be used with the cover of Figure 9A; Figure 10 – shows an ment of an electrical device, in the form of a wall box, according to another aspect; Figure 11 – shows an embodiment of the base of the wall box of Figure 10; Figure 12A – shows an ment of the base of Figure 11 in which the base is made up of a base part and a frame or grid; Figure 12B – shows an embodiment of a cover for use with the base of Figure 12A; Figure 13 – shows a rear perspective view of the base of Figures 11 and 12A, showing an embodiment of a second part of a locking mechanism; Figure 14A – shows a rear perspective view of an embodiment of the cover of Figure 11B showing a first part of the locking ism; Figure 14B – shows a rear view of the cover of Figure 14A showing the T-shape of the first part; Figure 15A – shows a rear view of the wall box with the cover locked to the base via the locking mechanism; Figure 15B – shows a close-up perspective cross-sectional view of the locking mechanism; Figure 15C – shows a side sectional view of the locking mechanism; Figure 16A – shows a side cross-sectional view of the locking mechanism at a first stage of the locking/unlocking s; Figure 16B – shows a rear view of the arrangement of Figure 16A; Figure 17A – shows a side cross-sectional view of the locking mechanism at a second stage of the locking/unlocking process; Figure 17B – shows a rear view of the arrangement of Figure 17A; Figure 18A – shows a side cross-sectional view of the locking mechanism at a third stage of the locking/unlocking process; Figure 18B – shows a rear view of the arrangement of Figure 18A; Figure 19A – shows a side cross-sectional view of the g mechanism at a fourth stage of the locking/unlocking process, in the locked position; Figure 19B – shows a rear view of the arrangement of Figure 19A; Figure 20A – shows a side cross-sectional view of the locking mechanism at a fifth stage of the locking/unlocking process in an unlocked position; Figure 20B – shows a rear view of the arrangement of Figure 20A; Figure 21A – shows a side cross-sectional view of the locking mechanism at a sixth stage of the locking/unlocking process; Figure 21B – shows a rear view of the arrangement of Figure 21A; Figure 22 – shows a path of the first part of the locking mechanism through the second locking ism according to one embodiment; Figure 23 – shows a path of the first part of the locking mechanism through the second locking mechanism according to another embodiment; Figure 24 – shows a path of the first part of the locking mechanism through the second locking mechanism according to another embodiment; Figure 25 – shows a path of the first part of the locking mechanism h the second locking mechanism according to yet another embodiment; Figure 26 – shows another ment of the electrical device as a wall box; Figure 27 – is a art of a method of g a cover to a base; and Figure 28 – is a flowchart of a method of unlocking a cover from a base.

DESCRIPTION OF EMBODIMENTS Figure 1 shows an embodiment of an electrical device 300 to which s described herein may be applied. In some embodiments, electrical device 300 is a wall box. In some aspects, the wall box 300 comprises a base 100 and a cover 200 which in use, is slid over the base to e the arrangement.

Figure 1 also shows the provision of a locking mechanism 40, which in some aspects, comprises a first part 41 disposed on the cover 200, and a second part 42, ed on the base 100, for locking the cover 200 to the base 100.

As seen in Figure 1, the first and second locking parts 41, 42 are engaged, as the cover 200 is slid over the base 100, and as will be described in more detail below.

Figure 2 shows the cover 200 and the base 100 connected and locked together via the engaged first and second parts 41, 42. This arrangement prevents the cover 200 from being removed from the base 100.

Figure 3 shows a rear view of the electrical device 300, in the connected and locked arrangement of Figure 2. ing to one aspect described herein, cover 200 is deformable, such that upon application of a force or pressure by a user on the cover 200, the cover is deformed or distorted such as to change the relative positions between the first part 41 and the second part 42 so as to disengage them from each other, thereby unlocking the locking mechanism.

Figure 4A shows the application of pressure (see arrows) into the sides of the cover 200, causing the top part of the cover 200 to rise up, lifting with it, first part 41, thereby disengaging the two arts to unlock the cover 200 from the base 100, as seen in Figure 4B.

This allows the cover 200 to be slid away and removed from base 100, as shown in Figure 4C.

In some embodiments, the deformation of the cover may be accomplished by other means including applying internal upward pressure to the cover top by ing a river or other tool through the rocker entry aperture once the rocker is removed.

In some aspects, the electrical device 300 is a grid and face plate arrangement of a surface-mounted switch and/or General Power Outlet (GPO), as described in more detail with respect to Figures 5A to 9B.

Figure 5A shows a front perspective view of a general embodiment of base unit 100 and Figure 5B shows a rear perspective view of the base unit 100 of Figure 5A. In one aspect, the base unit 100 comprises a mounting region 110 for mounting the base unit 100 to the surface. In some embodiments, the e is a wall. In some other ments, the surface is a floor. In some other embodiments, the e is a wall of a box or other enclosure. In other ments, the surface is a frame for supporting the base unit.

In some embodiments, the mounting region 110 is itself a surface which will come into contact with the surface to which the base unit 100 is to be d. In other embodiments, the mounting region 110 is a pin, tab or other connector.

As shown in Figure 5A, base unit 100 also comprises a base connector 120 for connecting the base unit to a cover unit 200 as will be bed in more detail below. The base connector is shown generically in Figure 5A but can take on any form that allows connection of the cover unit to the base unit 100. Such forms include a recess for receiving a protrusion from the cover unit, a protrusion for being received in a corresponding recess in the cover unit, a clipping arrangement, or a magnet for attracting and retaining a region of the cover unit. In other embodiments, the base connector is an adhesive, or a loop-hook connector such as a t sold under the trade mark Velcro® by Velcro Industries B.V. In this embodiment, base connector 120 can be either the loop component of the connector or the hook component.

Base unit 100 also comprises a base supply power input 130 for electrically connecting the base unit 100 to a supply or mains power supply (see Figure 5A). In some countries, the mains, or supply power is provided as an alternating current (AC) electrical signal of about 240V (for example between about 220V and 260V) and about 50Hz frequency. In other countries, mains or supply power is provided as an AC signal of n about 100V and 130V. Some systems use a frequency of about 50Hz while others use a frequency of about 60Hz. Some supply power systems are single phase and others may be three-phase. It will be understood that any electrical power that would be considered to be supply or mains power can be used.

In some embodiments, base unit 100 will also comprise a base power output 150 (see Figure 5A) for providing output power to the cover unit 200 when cover unit 200 is connected to base unit 100.

Base power output 150 can be provided by any suitable means including a direct plug/socket arrangement with a recess provided in base unit 100 leading to conductive elements which make ical connection with a corresponding electrically conductive element of a cover unit power input 210 (see below), or can be provided by a radiating element that transfers power from base unit 100 to cover unit 200 by induction or other means. An example of this embodiment is described in more detail below. Any other form of power er can also be used.

In some embodiments, base power output 150 and base connector 120 can be provided by the same element. In one such embodiment, the connection of cover power input to the base power output 150 will also provide sufficient support to retain cover unit 200 to base unit 100 without a further additional base connector 120 or other connection arrangement.

In some embodiments, base unit 100 will also se a power converter 140 which converts the supply input power received at the base supply power 130 input to the output power provided by the base power output 150 to provide useable power to the cover unit 200 when in In some embodiments, the base power output will be shielded or otherwise protected so that no electrically-live element is easily accessible by a user when the base unit 100 is led.

In some embodiments, the default state of the base power output is to an OFF state and is electrically isolated from the mains or supply power, and/or from the output of the power ter 140. In such an embodiment, only when the cover unit 200 is in place will the base power outlet be ically connected to the mains or supply power and/or the output of the power converter 140.

Figure 6 shows an embodiment of base unit 100 and cover unit 200 connected together, with base unit 100 mounted to a surface 40 (e.g. a wall), and mains or source power 50 ted to the base supply power 130 input.

In other embodiments, base unit 100 also comprises a base switch ace 160 for interfacing with a switch element of the cover unit 200, to allow actuation of a switch on the cover unit 200 to be effected on the base unit 100. Figure 7 shows a base unit 100 with base switch interface 160. In some embodiments, base switch interface 160 is an electrical interface such as a radio ncy (RF) receiver for receiving RF signals from a switch on the cover unit 200 when actuated. In some embodiments, base switch interface 160 is an infrared (IR) er for receiving IR signals from a switch of cover unit 200. In other embodiments, base switch interface 160 is a component of a touch switch which actuates upon a user touching or neartouching a corresponding switch element on the cover unit 200. An e of such a touch switch arrangement is described in PCT patent application no. 2011/001675 (published In other embodiments, base switch interface 160 is a mechanical interface for engaging with a switch element or a cover switch ace of cover unit 200 as is described in more detail in Australian Patent Application No. 2015275225 previously incorporated by nce in its entirety.

Figure 3 shows a general representation of the components of an ment of a switch assembly, connected to base unit 100 according to one aspect. Broadly, in this aspect, switch assembly 500 comprises two sub-assemblies, being base unit switch part 510 and operational part 1200. As shown in Figure 7, base unit switch part 510 comprises a functional part 1000 and a base switch interface 160.Operational part 1200 is for actuation by a user and for controlling the functional part 1000, via the base switch interface 160, for interfacing the functional part 1000 and the operational part 1200.

It will be noted that the operational part 1200 is not fixed to the base switch interface 160 or the functional part 1000 and is able to move freely with respect thereto as discussed in more detail in Australian Patent Application No. 2015275225 previously referred to, as well as Australian Patent Application No 2015275227 entitled “Switch Assembly, System and Method”, Australian Patent ation No 2015275234 entitled “Push Button Switch Assembly, and Operational Part”; and Australian Patent Application No 2015275233 entitled “Switch Assembly with Rotatable ional Part”, all previously incorporated by reference in their entirety.

It will be understood that there can be any combination of different operational parts 1200 and plates or cover units 200. For example, a switch assembly 500 with a small dolly 1201B might be converted to a switch assembly with a big dolly 1201B by replacing the operational part 1200 with a small dolly as described above. In r example, a switch assembly with a round push-button switch might be converted to a switch assembly with a square push-button/rocker switch by changing the ional part and the plate. In another combination, as shown in Figure 4, the appearance of system 300 may be changed completely by changing the existing plate or cover unit 200 with a plate or cover unit 200’ of a different type. In one embodiment, the user ace 1201 can be used, or a different user interface 1201 can be used. In the example of Figure 8, the switch interface 1201 is changed from a round dolly 1201B to a square dolly 1201B’.

Figure 9A shows a perspective view of an electrical system 300 according to some embodiments, and in this example, a general power outlet (GPO). Shown there is cover unit 200 (in this case a face plate), with power sockets 111, and switch user interfaces 1201, 1201’, in this example being switch rockers.

Face plate 200 covers base unit 100 (in this case, a grid plate as shown in Figure 9B), as will be tood by the person d in the art.

The locking mechanism 40 may be applied to any of these arrangements to lock the cover or face plate 200 to the base unit 100. In these embodiments, the cover 200 may support the first part 41 of the locking mechanism, and the base 100 may support the second part 42 of the locking mechanism.

Figure 10 shows an embodiment of electrical device 300 as a wall box, with cover 200 and switches 1201B and sockets 111.

Figure 11 shows a base 100, to which the cover 200 is connected.

Figure 12A shows an embodiment of the base 100 of Figure 11 in which the base 100 comprises a base part 110 for mounting to a surface, and a frame or grid 155. In these embodiments, the frame or grid 155 support the sockets 111 and switch interfaces 160 usly described with reference to Figure 7 for example.

Figure 12B shows an embodiment of the cover 200 for connection to the base 100 of Figures 11 and 12A. The means of connection of the frame or grid 155 to the base part 110 can be any suitable means, including by way of clips or friction-fit.

Figure 13 shows a rear perspective view of a base 100 (in this embodiment, base part 110) of Figure 12A. Seen in this view is second part 42 of locking mechanism 40. In this ment, second part 42 comprises a channel 42a in the surface of base part 110, with at least one (in this embodiment, two) protrusions 42b, which extend at least partially, over the channel 42a.

Figure 14A shows a rear ctive view of an embodiment of cover 200, showing the first part 41 of the locking mechanism 40. In this embodiment, as also highlighted in Figure 14B, the first part 41 comprises a “T-shaped” portion 41a, the e of which will be described in more detail below.

Figure 15A shows a rear view of connected cover 200 and base 100, g the locking mechanism 40. Figure 15B shows close-up cross-section of the engagement of Figure 15A. In particular, it can be seen that a part of the T-shaped portion 41a is engaged with protrusion 42b of the second part 42 of the g mechanism 40, such that any backwards force on cover 200 is opposed by the protrusion 42b, thereby g the cover 200 to the base 100.

Figure 15C shows a side view of this engagement, showing T-shaped portion 41a engaged with protrusion 42b to resist a force imparted on the cover 200 to remove it from base To disengage T-shaped portion 41a from sion 42b, a force or re is applied to the sides of cover 200 as previously described with reference to Figures 4A and 4B to cause cover 200 to be ed, causing the T-shaped portion 41a of first part 41 to move upwards and disengage from the second part 42, thereby unlocking the cover 200 from the base 100, and allowing it to be removed from the base 100.

Figures 16A to 21B show this process over a number of stages. Figure 16A shows the cover 200 about to be slid over the base 100. Figure 16B shows a rear view of this arrangement.

As the cover moves forward (to the right in the view of Figure 16A), the first part 41, and in particular, the T-shaped portion 41a of locking mechanism 40, enters channel 42a of second part 42, as shown in Figure 17A.This may be accomplished by a number of methods, including the natural resiliency of the cover, or the angle at which the user slides the cover, or the user g down on the cover over the first part 41. In other embodiments, the protrusion(s) 42b or other driving element may encounter the first part 41 and is shaped so as to drive first part 41 down into the channel 42a as the cover 200 is slid over the base 100. Figure 17B shows the T- shaped portion 41a below the level of protrusion 42b of the second part 42.

As the cover 200 continues to be slid over the base 100, the T-shaped portion 41a slides underneath the protrusion(s) 42b as shown in s 18A and 18B. As the cover 200 is slid all the way over the base 100, and past the protrusion(s) 42b, the T-shaped portion 41a “pops” s, due to the resiliency of the material of the cover 200, so as to lie “behind” the protrusion(s) 42b, thereby locking the cover 200 to the base 100 as shown in Figures 19A and This reduces the risk of the cover 200 being accidentally removed from the base, and requires concerted and intended action to unlock the cover 200 from the base 100 and remove it.

When a user wishes to remove the cover 200 from the base 100, the user applies pressure to the sides of the cover 200 as previously bed, causing the first part 41 to rise above the protrusion(s) 42b as shown in Figures 20A and 20B, thus unlocking the cover 200 from the base 100, and as shown in Figures 21A and 21B, allows the cover 200 to be slid backwards and removed from the base 100.

It will be appreciated that the force or pressure applied to the cover to deform it to cause the locking parts to disengage may be applied in various ways, including applying a “pulling force” on the top of the cover above the first part 41, or applying a pushing force below the cover 200 to cause the entire cover 200 to shift s slightly.

While the locking process has been described above with reference to one embodiment, it will be appreciated that the same, or different embodiments may provide for a different process. Figures 22 to 25 show various different possible paths or processes for the locking and unlocking to occur.

In Figure 22, the path shown is as that described above with reference to Figures 16A to 21B. In Figure 23, a different path is shown, in which the g path is the same as in Figure 22, but the unlocking path is the reverse. In this ment, when unlocking the cover 200, rd pressure is applied to the cover 200 above the first part 41, to cause the T-shaped portion 41a to again drop down below the sion(s) 42b and into the channel 42a, to allow the cover 200 to be slid away from the base 100.

Figure 24 shows another path that is the reverse of the path of Figure 22. In this embodiment, the cover 200 is slid over the base 100 such that the first part 41 remains above the second part 42 until the first part 41 reaches the end of the protrusion(s) 42b, at which time the first part 41 drops down in front of the second part 42 to lock the cover to the base. The ng down action can be created by a number of means, including the l resiliency of the cover 200. To unlock the cover 200 from the base 100, downward pressure is applied to the cover above the first part 41, causing it to enter the channel 42a and be withdrawn therethrough, as in the unlocking path of Figure 23.

Figure 25 shows a path that is a combination of the locking path of Figure 24 and the unlocking path of Figure 22.

Figure 26 shows another embodiment of an electrical device 300 as a wall box, having a single socket 111 and switch 1201B. It will be appreciated that any combination of sockets, no sockets, switches, no switches and other elements may be provided.

Figure 27 shows a art of a method according to one , of locking a cover 200 to a base 100. As shown in step 800, the cover 200is simply slid over the base 100 to cause the first part 41 of locking ism 40 on cover 200 to engage with second part 42 of locking mechanism 40 on the base 100 to lock cover to base.

Figure 28 shows a flowchart of a method of unlocking a cover 200 from a base 100 according to one aspect. As shown in step 900, the cover 200 is deformed to cause the first part 41 of the g mechanism 40 on the cover 200 to disengage with second part 42 of the locking mechanism 40 on base 100 to unlock cover from base and then in step 910, the cover 200 is slid from the base 100 to thereby remove the cover 200 from the base100.

] It will be appreciated that many variations of the embodiments detailed above are possible, For example, the first part 41 of the locking mechanism 40 may be provided with an “L-shaped” or “J-shaped” portion rather than a ped” portion, so that there is only one element that interacts with a corresponding sion 42b of the second part 42. In other embodiments, the second part 42 can have only one sion to engage with the first part 41. In other ments still, the channel and protrusions 42b may be provided on the cover 200 where the material is sufficiently thick, and the T-shaped, L-shaped, J-shaped or other-shaped portion may be provided on the base. In other embodiments still, where the base 100 comprises a base part 110 and a frame or grid 155, the second part 42 of the locking mechanism may be provided on either the base part 110, or the frame or grid 155, or may be distributed over both parts.

Throughout the specification and the claims that follow, unless the context requires otherwise, the words “comprise” and “include” and variations such as “comprising” and “including” will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers.

] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement of any form of suggestion that such prior art forms part of the common general knowledge.

It will be appreciated by those skilled in the art that the invention is not restricted in its use to the particular application bed. r is the present invention restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that the invention is not limited to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims.

Claims (13)

1. An electrical device comprising: a base for mounting to a e; and a cover for covering at least a portion of the base; wherein the cover comprises a first part of a locking mechanism and the base comprises a second part of the locking mechanism which when d, lock the cover to the base, and wherein the first part and the second part of the locking mechanism are caused to engage to lock the cover to the base upon connecting the cover to the base.

2. An electrical device as claimed in claim 1 wherein at least a portion of the cover is deformable such that upon deformation the first part and the second part of the g mechanism disengage to unlock the cover from the base.

3. An electrical device as claimed in any one of claims 1 or 2 wherein the second part of the g mechanism comprises: a channel in the base for ing at least a portion of the first part; and at least one protrusion protruding over at least a portion of the channel; wherein in use, as the cover is ted to the base, the at least a portion of the first part of the locking mechanism is received within the channel and slides between a floor of the channel and the protrusion, and then once the at least a portion of the first part of the locking mechanism passes beyond the protrusion, the first part engages with the protrusion to thereby lock the cover to the base.

4. An electrical device as claimed in claim 3 wherein the first part comprises a ed portion for being received between the protruding part and the floor of the channel.

5. A cover for connection to a base of an electrical device, the cover sing a first part of a locking mechanism for engaging with a second part of the locking mechanism, the second part disposed on the base and wherein the cover is deformable to allow movement of the first part relative to the second part of the locking mechanism when the two parts are engaged.

6. A cover as claimed in claim 5 wherein the first part of the locking mechanism comprises a T-shaped portion for being received in the channel of the base and engaging with a protrusion of the second part.

7. A base for tion to a cover as claimed in any one claims 5 or 6, the base comprising a second part of a locking mechanism, the second part comprising: a channel for receiving the first part; and at least one protrusion extending over at least a part of the channel, for ng with the first part of the locking ism.

8. An electrical device comprising: a base for mounting to a surface; and a cover for covering at least a portion of the base; wherein the cover comprises a first part of a locking mechanism and the base comprises a second part of the locking mechanism which when engaged, lock the cover to the base, and n the first part and the second part of the locking mechanism are caused to disengage to unlock the cover from the base upon deforming the cover or the base.

9. A method of unlocking a cover from a base of an electrical device, the method comprising: deforming the cover to cause a first part of a locking ism to disengage from a second part of the locking mechanism disposed on the base; and sliding the cover from the base.

10. An electrical device as claimed in any one of claims 1 to 4 n the electrical device is a wall box.

11. A cover as claimed in any one of claims 5 and 6 wherein the cover is a cover of a wall

12. A cover as claimed in any one of claims 5 and 6 n the cover is a face plate.

13. A base as claimed in claim 7 wherein the base is a grid plate.