PLUG-IN ELECTRICAL ACCESSORIES

Abstract: An electrical accessory box with a complete suite of plug-in wiring accessories (socket outlets/receptacles, lighting switches, etc.) for use on a conventional conduit system that allows the wiring system within a building to be fully wired, connected and tested at an early stage in the construction. The devices would be fully interchangeable for differing national standards and easily replaced by non technical persons. The accessory range would cover all devices required within a building and be designed to comply with national and international standards.

Description: Plug-in Electrical Accessories The Description Technical Field The invention is a new type of electrical wiring accessory that provides early completion of the wiring within a building to allow full testing of the system by using a plug-in accessory. It also provides an adaptability that permits easy interchangability of outlets to suit differing national standards and outlet types. Background Art The problem in the installation of electrical accessories in buildings has always been that conduits and cables are installed early in the construction programme and then tested and connected to the accessory at the end. Should a failure of a cable occur, it will not be discovered until much later when it can often be difficult to access the conduit with all the other services and architectural finishes in place. The replacement of cables is generally quite time consuming. With the systems in use at present, the cables once installed are left loose or wound up in the accessory box where they are subject to damage. The accessory box is often filled with cement or plaster as the wall finishes are applied. In order to test and commission the wiring system the cables have to be terminated which means the accessories and luminaires have to be installed. This makes the testing of the complete lighting circuit very difficult; either the lamps are removed or, in the case of fluorescent luminaires, the lamp circuits are disconnected or, as normally happens the light switches are in the "off position. With the light switches off. the phase conductors to the luminaires, i.e. the switch lines, are not tested! Due to the testing and commissioning of the wiring system, the accessories themselves are normally installed before the final painting of walls. This often leads to the accessory being 'painted' along with the walls, sometimes requiring the accessory to be replaced or at the very least needing extensive cleaning. Some contractors try to cover the accessory with a tape to avoid the paint damage, but this is time consuming and not very successful. Once the building is in use. it will in time need repainting, and then the problem arises again. With the growing diversity of building tenant / owner nationalities in all countries there is sometimes a desire to have different accessory types (American, British, German, pattern of accessory). Changing the accessory type on the existing systems is not easy, and will generally need an electrician to carry out the work. The plug-in electrical accessory (the Invention) has been developed to overcome these problems. Disclosure of Invention The invention is an accessory box with a plug-in accessory plate for use on a conventional conduit system that overcomes all the problems noted in the background to the Invention and noted below. This device is a complete suite of electrical accessories that allows the wiring system within a building to be fully wired, connected and tested at an early stage in the construction. As stated earlier, in order to test and commission the wiring system the cables have to be terminated which means the accessories and luminaires have to be installed. This requires either the lamps to be removed or, in the case of fluorescent luminaires, the lamp circuits to be disconnected. What normally happens is the light switches are in put in the "'off position which means the phase conductors to the luminaires, i.e. the switch lines, are not tested. This can sometimes be a considerable percentage of the circuit wiring. The invention overcomes this by allowing all the circuit conductors to be installed and terminated without connecting the luminaires or the accessories, thus full testing can be carried out. All the finishes can be applied to the building and then the accessories plugged in, thus avoiding damage to the accessory by the finishes and visa versa. The accessory comprises three basic parts : a) the accessory box (Fig 3)which is installed with the conventional conduit system b) the accessory itself (Fig 6) which is a socket/outlet/receptacle, lighting switch, etc. c) a temporary cover plate (Fig 8) which can be replaced with a maintenance cover plate. The accessory box provides permanent termination of the wiring with plug-in facilities for the accessory. The accessory, which could be socket outlet, lighting switch, ceiling rose, or whatever, plugs into the accessory box providing connection to the external circuit. Upon completion of the room finishes, the accessory is simply plugged into the accessory box and is ready for use without any further installation required. If it is necessary to redecorate the room, it is a simple matter to unplug the accessory, fit the temporary cover plate, decorate, remove the cover plate and then plug the accessory back in. It does not need an electrician. If the decorating is to be done at night or the room has no windows then a maintenance cover plate (a plug-in lighting switch bypass) can be installed. This would be similar to the temporary cover plate and would inter-connect the wiring to keep the lighting on for as long as the device is in place. With 2-way and intermediate switching, removing one of the 2-way or intermediate switches would not affect the operation of the other, so there would be no need to by-pass the switch. If for any reason the accessory type, i.e. American pattern accessories, are required to be changed for say German pattern, it is only necessary to unplug one device and replace it with the other. The accessory range would cover all devices required within a building and would fully comply with national and international standards. All devices would be rated at 250V to allow for any national voltage. The Accessory Box (Fig 3) The accessory box is a moulded plastic box (1) arranged to connect to a standard conduit system (2) using a male bushing into a conduit coupler (3). The external sides of the box are flanged (4) to link another accessory box onto any of the four sides. This allows accessory boxes to be joined together to form multi-ganged arrangements up to any number in a matrix form. The flanges ensure that the alignment and spacing of a group of accessories is accurate and consistent. Fig. 5 shows typical elevations of the accessory box. These same flanges are used to provide fixation when the boxes are recessed into a block or concrete wall. They also act as 'wings' behind plasterboard in a dry partition to prevent the box pulling through. The box would have fixing holes (5) in the base, set to allow for minor re-alignment. Conduit entries are provided on each side; two on the top and bottom side (6) and one on the other two sides (7). Each box when joined to others, can interconnect to it's adjacent box through the conduit entry holes or they can be blanked off as necessary. This allows wiring devices of different voltage grades to be installed adjacent to each other and maintain segregation of the wiring as required by the national and international regulations. Inside and on each side of the box are the cable connection terminals (8). There are twelve terminals for low current devices rated at 10 amps and below such as light switches and controls and eight terminals for power outlets (and higher rated light switches) rated up to 20 amps. The terminal could be a barrel screw terminal as shown or any other type. Each of the terminals are connected to a live rail (9) which is encapsulated in a slot ( 10) that takes the leg of the accessory. The accessory when inserted in the slot (10) will connect it (Fig 6) to the cable system by the live rail (12) in the accessory being in pressure contact with the live rail (9) in the accessory box. Fig. 7 shows the detail of the live rail connection between the accessory and the accessory box. The fixing of the accessory to the accessory box is by sliding the legs (18) of the accessory into the live rail slots (10) of the box. When the accessory is pushed down on to the top of the box, a fixing clip (11) will hold the accessory in place. The accessory is removed by lifting the edge of the accessory with the flat blade of a screwdriver in the slot provided and disengaging it from the fixing clip. The Accessory (Fig 6) The arrangement shown in Fig 6 describes a typical socket outlet/receptacle for a British system. Variations on this would be used for the other types of outlet and also for direct cable connection to luminaires and appliances, etc. The accessory comprises two main parts; the wiring device (13) and the cover plate (14). The wiring device would be a standard design for each type of accessory. The cover plate, made of either plastic or metal, would be stylised to suit the architectural design and finish of the accessory and would be factory fixed to the wiring device. As a socket outlet, as shown in the drawings, the wiring device ( 13) is a plastic assembly incorporating a recess (15) for the spring clip (16) for the appliance plug (24) to connect to; and the live conductors (17) which become the live rail (12) which are connected to the accessory leg (18). The back of the leg is angled (19) to provide additional support for the live rail when under pressure from the contact with the live rail in the accessory box. When the accessory is a switch or other such device that interconnects parts of the fixed building wiring system, the wiring device will interconnect the appropriate live rails in the legs to make the necessary interconnections. The two live rails are arranged to have a slight interference fit when the accessory is inserted into the accessory box. Pressure is maintained, to ensure a positive contact between the two, by the inherent tension in the accessory leg due to the shape of the leg. The leading edge of the live rails (9 & 12) are shaped (21) to allow easy entry of the accessory leg (18) into the live rail slot (10) in the accessory box. The top section of the live rail is encapsulated in plastic (20) to prevent access to the accessory live rail (12) once the rail is in contact with the accessory box live rail (9). The earthing/grounding rail will be longer than the live rails to ensure positive earth connection before any live connections are made. For a power outlet, the plug-in facility will provide connections allowing it to be used for but not limited to a) a single phase socket outlet (live, neutral and earth), switched or unswitched b) a two phase socket outlet (live l,live 2. neutral and earth), switched or unswitched c) a three phase socket outlet (Red, Yellow and Blue phases, neutral and earth), switched or unswitched d) a 20 amp double pole switch (live and neutral supply; live and neutral load; and earth) e) a fused connection unit (live and neutral supply; live and neutral load; and earth), switched or unswitched. f) isolators and isolating switches up to 20 amp rating The connections are always in the same location irrespective of the type of accessory to enable complete interchangability (provided the circuit connections are available in the box). For a lighting device, the plug-in facility will provide connections allowing it to be used for but not limited to a) 1 way lighting switches b) 2-way lighting switches c) Intermediate lighting switches d) Lighting controls including dimmers and infra-red controls, etc. e) Ceiling roses f) Connection boxes to luminaires g) Switch by-passes for maintenance purposes The connections are always in the same location irrespective of the type of accessory to enable complete interchangability (provided the circuit connections are available in the box). For other devices, the plug-in facility can be provided in different configurations, allowing it to be used for a wide number of other connections including but not limited to a) HVAC controls b) Audio outlets c) Telephone outlets d) Data outlets e) TV and Radio outlets f) Clocks; both mains and central g) Others The accessory incorporates the switch, socket outlet, etc. connected internally to the plug-in legs which mate with the accessory box. Once plugged in the device is connected to the supply. The Temporary Cover Plate (Fig 8) Although the Temporary Cover Plate does not form part of the invention the description hereunder is added for completeness of the system. The temporary cover is a flat clip-on plastic cover that fits level with the top of the accessory box. This firstly protects the cabling inside and provides a surface level with the surrounding finishes to allow plastering and decoration to proceed without having the accessory fitted. The temporary cover (22) is a flat plastic cover that fits into the recess at the top of the accessory box. This also has legs (23) to align with the live rail slots (10) in the accessory box. These do not carry a live rail. The Maintenance Cover Plate Fig (8) For maintenance purposes and redecoration, a maintenance cover plate, similar to the temporary cover plate, complete with live rails would be used as a lighting switch bypass. The live rails would be interconnected to simulate a closed switch. Schedule of Element Numbers 1 Accessory Box 14 Cover plate 2 Conduit system 15 Spring clip recess 3 Conduit coupler 16 Spring clip 4 Accessory box flanges 17 Live conductors 5 Accessory box fixing holes 18 Accessory leg 6 Conduit entry hole 19 Angled support for the leg 7 Conduit entry hole 20 Encapsulation of accessory leg 8 Cable connection terminals 21 Shaped end of live rails 9 Accessory box live rail 22 Temporary Cover 10 Live rail slot 23 Legs of temporary Cover 11 Accessory fixing clip on the accessory box 24 13 Amp plug 12 Accessory live rail 25 Wall 13 Wiring device 26 Plaster Brief Description of Drawings The drawings have been produced to show the principle elements of the invention, sufficient to enable a manufacturer to develop the system to a production product. The system covers a large variation in types of electrical accessories, therefore, the drawings have only been produced to show one type. The principles of the invention do, however, apply equally to the other variations. Fig 1 shows the general arrangement of the invention with the two principle parts, viz. the accessory box and the accessory. The elevation indicates how the parts, including a plug- would fit together. Fig 2 shows a section of the complete assembly Fig 3 shows the detail of the accessory box based upon an accessory with a rating above 10 Amps, such as a socket outlet/receptacle. Fig 4 shows a section through the accessory box to show the arrangements for the 4 no. 20 Amp terminals. Fig 5 provides elevations of the accessory box indicating the arrangement of the flanges and the conduit entries. Fig 6 describes the accessory in detail based upon a British style 13 Amp socket outlet/receptacle. Fig 7 shows the detail of the live rail. Fig 8 shows the temporary cover plate. The maintenance cover plate is similar. Best Mode for Carrying Out the Invention The existing methods of plastic injection moulding and production of electrical wiring accessories would apply to the production of this invention. Industrial Applicability The domestic accessory market with the inventions adaptability for redecoration. Due to it's plug in facility it would also be easy to change the accessory to suit a change in interior decoration style or colour. The commercial market where there is a need to have the facility to interchange the accessories to have more than one nationality type of socket outlet to suit different equipment with moulded plugs. The contractor market where a) the ability to install the accessory box, terminate the wiring and test the cables at a very early stage in the installation would be a tremendous advantage. b) installing the accessory plates at the end of the project, when time is always critical, takes a matter of seconds per unit instead of 15-30 minutes for a conventional accessory. c) the accessory itself need not be installed until after the final decoration and perhaps not until immediately before hand-over of the building. This avoids damage to the accessory and reduces pilferage. d) changes made by the client during construction to the style and type of accessory required becomes only a problem of procurement - not installation. Plug-in Electrical Accessories The Drawings The following drawings descπbe. together with the foregoing text, the detail of the invennon Fig 1 The General Arrangement of the Invention Fig 2 Section of the Complete Assembly Fig 3 The Detail of the Accessory Box Fig 4 Section through the Accessory Fig 5 Elevations of the Accessory Box Fig 6 The Accessory Fig 7 Detail of the Live Rail Fig 8 The Temporary Cover Plate

Claims: Plug-in Electrical Accessories The Claims The invention is a complete suite of plug-in electπcal accessoπes for connection to fixed electπcal conduit systems and other systems commonly m use in buildings The invenϋon consists of accessory boxes, wiring accessoπes, and maintenance covers (Temporary covers for use with the invention are noted in the Description of the Invention but do not form part of the invention) The accessory box allows the fixed cabling in a building to be fully connected early in the construction process, without having the accessory installed This allows the fixed cabling to be tested much earlier than has been possible hitherto, and the accessory installed after final painting The invention's wiring accessoπes, such as socket outlets, switches and other electπcal devices, plug-rn to the accessory box and are designed for use with conventional appliance plugs, lighting circuits, etc Maintenance covers within the scope of the invention can be installed to replace the wiring accessory to provide continued use of specific circuits duπng building maintenance The plug-in electπcal accessoπes accordmg to Claim No 1 have a configuration of the accessory box arranged with a standard internal layout for the connections so as to permit the interchangability of wiring accessoπes of the same geneπc type and ratings The plug-m electπcal accessoπes, according to Claim No 1, have electπcal accessoπes specifically designed in accordance with the invention to accept appliance plugs commonly used in and around a building The plug-in electπcal accessoπes. accordmg to Claim No 1, have electπcal accessoπes specifically designed in accordance with the invention as switches and other electπcal control devices commonly used and around a building The plug-in electπcal accessoπes according to Claim No 1 allows for the simple plug-rn interchangability of the invention accessoπes complying with differing international standards The electπcal accessory box according to Claim No 1 incorporates a set of cable terminals embedded m the wall of the accessory box to allow the connection of the building ' s fixed winng system This enables the building wiπng to be tested pπor to the installation of the wiring accessory itself Embedded terminals accordmg to Claim No 6 are connected to an embedded live rail set m a shaped slot that is configured to prevent inadvertent touching of the live rail and to accept a leg of the accessory The electrical accessory, accordmg to Claim No 1, has a multiplicity of legs shaped to fit into the slots m the side walls of the accessory box and that has an embedded live rail to make contact with the live rail in the accessory box The plug-m electπcal accessoπes according to Claim No 8 have a live rail on each leg that when pushed into the accessory box, the live rail in the accessory box is under pressure from the accessory live rail due to the special profile of the accessory leg. This provides safe electπcal connection between the two live rails The plug-m electπcal accessoπes accordmg to Claim No 1 includes a mamtenance cover plate that permits switches to be bypassed duπng building maintenance Tins incorporates live rails as in Claims 8 and 9 that are permanently interconnected to bπdge out the switch circuit The accessory box according to Claim No 1 has specially arranged flanges on the four sides of the accessory box These are designed to allow boxes to be joined together to form multi-ganged arrangements up to any number in a matrix form and to maintain the correct oπentation of the boxes to ensure the correct wiring arrangement Each box can interconnect to its adjacent box through the conduit entry holes or they can be blanked off as necessary This allows wiring devices of different voltage grades to be mstalled adjacent to each other and mamtam segregation of the winng as required by the national and mtemational regulations. The flanges also ensure that the multi-ganged arrangement is correctly spaced and aligned to accept multiple accessoπes.

Inventors: DEBOECK PETER ANTHONY, DEBOECK, PETER, ANTHONY
Applicants: DEBOECK PETER ANTHONY, DEBOECK, PETER, ANTHONY
Application year: 2000
Main classification: H02G3
IPC codes: H02G3