ZA200409748B - "An electrical distribution device". - Google Patents

Description

E«.2004/79748

THIS INVENTION relates to an electrical distribution device.

An electrical distribution device, as herein envisaged, comprises a devise that accommodates the distribution of electrical power from the secondary side of a transformer to two or more low voltage powered sub-circuits. The transformer typically transforms a high voltage alternating current supply e.g. 220 volts, supplied to its primary side, into a low voltage alternating or direct current power supply, e.g. between 6 volts and 50 volts supplied from its secondary side.

According to the invention there is provide an electrical distribution device, which includes a housing structure having walls that define an enclosed space, at least a part of at least one wall being displaceable to provide access into the enclosed space; a pair of input terminals located on the housing structure in a configuration in which the incoming power supply from the secondary side of a transformer can be connected thereto from the outside of the housing structure; and at least two pairs of output terminals located on the housing structure in a configuration in which each pair of output terminals can be connected to the respective conductors of a low voltage powered sub-circuit from the outside of the housing structure, the terminals of the pair of input terminals being connected to corresponding terminals of each pair of output terminals by wiring operatively housed in the housing structure .

The electrical distribution device thus provides a single device that can be used for distributing a low voltage alternating or direct current supply, as supplied from the secondary side of a transformer, to multiple low voltage powered sub-circuits, by suitable connection of the low voltage alternating or direct current supply from the secondary side of a transformer to the pair of input terminals and suitable connection of the low voltage powered sub-circuits to the pairs of output terminals.

According to one particular embodiment of the invention, the walls of the housing structure define a rectangular box-like structure. Also, the housing structure typically is formed of a synthetic plastics material, such as PVC, or the like, being manufactured by a conventional injection moulding process. It must be appreciated in this regard that the configuration of the housing structure is greatly variable and that the design thereof can be determined by particular requirements of the distribution device, in terms of intended applications of the device.

The pair of input terminals of the electrical distribution device may form part of a connector having contacts, electrically connected to the respective input terminals, to which the incoming power supply from the secondary side of a transformer can be connected to thereby be connected to the input terminals, the pair of input terminals thus being located on the inside of the housing structure and the contacts on the outside of the housing structure.

Still further, the pairs of output terminals of the electrical distribution device may form part of at least one terminal block in the form of a strip connector that is securely located on a wall of the housing structure, with the pairs of output terminals being located on the inside of the housing structure and pairs of contact terminals of the strip connector being located on the outside of the housing structure, each pair of contact terminals providing for connection of the respective conductors of a low voltage powered sub- circuit thereto and thereby connection to a pair of output terminals. One particular embodiment of the invention provides for the electrical distribution device to include pairs of output terminals that form part of two terminal blocks in the form of strip connectors, that are securely located on the same wall, or on different walls, of the housing structure.

It is envisaged in the above regard that the electrical distribution device may include any number of pairs of output terminals, for example, eight pairs of output terminals, or twelve pairs of output terminals. For an electrical distribution device that includes twelve pairs of terminals, the output terminals may form part of two terminal blocks that each incorporates six pairs of output terminals.

Further according to the invention, the electrical distribution device may include at least one electrical fuse that is operatively connected between the pair of input terminals and one of the pairs of output terminals, in line with the live terminals of the respective pairs of terminals. More particularly, the electrical distribution device may include an electrical fuse that is operatively connected between the pair of input terminals and each pair of output terminals in line with the live terminals of the respective pairs of terminals. The electrical fuses utilised either may have the same rating, or at least some of the electrical fuses may have different ratings, thus to accommodate different requirements.

Each electrical fuse of the electrical distribution device of the invention may be located in a space defined in a panel mounted fuse holder which is mounted on a wall of the housing structure in a configuration in which the fuse holder is disposed partially on the outside of the housing structure and partially on the inside of the housing structure, the portion of the fuse holder disposed partially on the outside of the housing structure including a removable screw cap that provides for replacement of a fuse located in the space defined in the fuse holder. For such a panel mounted fuse holder, the holder includes internal “wiring” that suitably connects connector formations thereof to a fuse located within the space within the fuse holder, the connector formations being located on the portion of the fuse holder disposed on the inside of the housing structure, permitting required connection between the pair of input terminals and each pair of output terminals, essentially by wiring located on the inside of the housing structure.

Each current line to a sub-circuit will thus have a fuse located in line therewith for safety purposes, the entire device being internally pre-wired and effectively sealed to ensure that the wiring cannot be easily interfered with.

The particular arrangement of the panel mounted fuse holders on a wall of the housing structure particularly is such that the line between the input terminals and the output terminals within which each fuse is operable is clearly apparent in relation to the arrangement of the output terminals with respect to the housing structure.

Still further according to the invention, the housing structure may be configured to be mounted on a support surface by securing one wall of the housing structure to the support surface, at least a part of the remaining walls of the housing structure being displaceable from the said wall, in order to provide access to the enclosed space defined by the housing structure.

Still further, the pair of input terminals of the electrical distribution device and each pair of output terminals may be associated with markings applied on the housing structure to indicate to which terminals live and neutral conductors must be connected, for use of the device.

It is envisaged that the circuitry of the electrical distribution device may include also additional functional components that can enhance the applications of the distribution device, additional components including, for example, a dimmer that can be used in association with lighting, or means to provide for variable low voltage supply to a low voltage powered sub-circuit. The above components also may be externally controllable via control means provided externally on the housing structure.

An electrical distribution device, in accordance with the invention, is described hereafter with reference to an example of such a device that is illustrated in the accompanying diagrammatic drawings. In the drawings:

Figure 1 illustrates schematically the layout and wiring of an electrical distribution device, in accordance with the invention;

Figure 2 shows an elevational front view of a particular embodiment of an electrical distribution device, in accordance with the invention;

Figure 3 shows a cross-sectional end view of the electrical distribution device of

Figure 2, along !lI-ll of Figure 2;

Figure 4 shows a schematic elevational front view of an alternative arrangement of the embodiment of the electrical distribution device, as shown in Figure 2; and

Figure 5 shows a schematic side view of the arrangement of the embodiment of the electrical distribution device, as shown in Figure 4.

Referring initially to Figure 1 of the drawings, an electrical distribution device is schematically illustrated and is designated generally by the reference numeral 10. The distribution device 10 includes a housing structure in the form of a box-like structure 12, a possible configuration of the box-like structure being described in more detail hereafter with reference to a specific embodiment of an electrical distribution device, which is illustrated in Figures 2 and 3 of the drawings.

The distribution device 10 includes a pair of input terminals 14 that are located at least partially within the space defined by the box-like structure 12, the terminals 14 permitting connection of conductor wires thereto at a location on the outside of the box- like structure 12, as is described in more detail hereafter.

The distribution device 10 includes also twelve pairs of output terminals 16 that are located in two groups of six, also at least partially within the space defined by the box- like structure 12, each pair of output terminals again permitting conductor wires to be connected thereto at a location on the outside of the box-like structure 12, as is described in more detail hereafter.

As is clearly illustrated in Figure 1 of the drawings, the distribution device 10 is pre- wired to provide for electrical connection of the pair of input terminals 14 to each pair of output terminals 16, the live wires extending from the pair of input terminals 14 to each pair of output terminals 16 having a fuse 18 connected in line therewith. It will be understood in this regard that the wiring can be provided for in many different configurations and, as such, this is not described in further detail herein.

The electrical distribution device 10 is particularly suitable for use between the secondary side of a transformer whereby, for example, a 220 volts alternating current power supply is transformed into a 12 volt direct current power supply, which is distributed to the output terminals 16 to permit connection to twelve different low voltage powered sub-circuits, each identified in Figure 1 by the numeral 20. The low voltage powered sub-circuits 20 are thus powered effectively by the 220 volts alternating current power supply via the transformer referred to. It must be understood in this regard that the electrical distribution device of the invention can be provided without fuses, where this is not required for the intended application of the distribution device, particularly in relation to the application of the sub-circuits to be electrically connected therewith.

By utilizing an electrical distribution device 10 in conjunction with the supply of low voltage power to a plurality of sub-circuits 20 from a power supply provided by the secondary side of a transformer, any malfunctioning within a sub-circuit connected to the distribution device will merely result in the relevant fuse to burn through, thus disabling the particular sub-circuit without affecting any one of the other sub-circuits. It is suggested in this regard by the Applicant that in conventional situations where a plurality of low voltage powered sub-circuits are connected to the secondary side of a transformer, where this connection usually is directly with the transformer, malfunctioning of any individual sub-circuit can cause damage to other sub-circuits also, as well as possibly to the transformer. This potential problem is thus effectively alleviated with the use of the electrical distribution device of the invention, as defined and described above.

Referring now particularly to Figures 2 and 3 of the drawings, a particular embodiment of an electrical distribution device, in accordance with the invention, is designated generally by the reference numeral 30. The distribution device 30 includes a housing structure in the form of a box-like structure 32, the box-like structure 32 including a base part 34, which has a plurality of holes 36 formed in a main wall 37 thereof, which permits securing to a support surface such as a support wall, particularly with securing screws, or the like. The box-like structure 32 also includes a carrier part 38, the base part 34 and the carrier part 38 defining surrounding side walls, 40 and 42 respectively, the side walls 42 of the carrier part being slidably receivable within the side walls 40 of the base part, as is clearly illustrated in Figure 3 of the drawings, to thereby provide for the location of the carrier part 38 with respect to the base part 34. Complementary clipping formations 44 provide for the secure location of the carrier part with respect to the base part, while still permitting displacement of the carrier part in order to provide access into the internal space 46 defined within the box-like structure 32. Clearly,

additional securing means may act between the base part 34 and the carrier part 38, in order to control access into the space 46.

The side wall 42.1, that defines one end of the carrier part 38 of the box-like structure 32, has a connector 48 securely located within an aperture provided therefor, the connector 48 defining a pair of contacts 50 on the outside of the box-like structure 32 and a pair of input terminals 52 on the inside of the box-like structure 32, particularly within the space 46. Each contact 50 is electrically connected to an input terminal 52 and by connecting conductor wires from the secondary side of a transformer to the contacts 50, these conductor wires are effectively connected to the input terminals 52.

The side walls 42.2 of the box-like structure 32 each have a terminal block in the form of a strip connector 54 securely located with respect thereto within apertures defined in these walls. Each strip connector includes six pairs of input terminals located on the operative inside of the box-like structure 32 and six pairs of contact terminals located on the operative outside of the box-like structure 32, the contact terminals clearly permitting connection to the wires of a low voltage powered sub-circuit, as herein envisaged.

The operative front wall 56 has twelve panel mounted fuse holders 58 securely located therein, each panel mounted fuse holder including a body portion disposed on the operative outside of the box-like structure 32 and a body portion on the operative inside of the box-like structure 32. Each panel mounted fuse holder 58 carries a fuse (not shown) therein and has a screw cap 60 that permits replacement of the fuse. It will be understood that the input terminals 52, the output terminals as provided by the strip connectors 54 and the fuses carried by the panel mounted fuse holders 58 are electrically connected to one another in the configuration as shown in Figure 1 of the drawings, thus providing an electrical distribution device having the functionality of the electrical distribution device 10 as described with reference to Figure 1 of the drawings.

Vee2004/9748

As is clearly apparent from Figure 2 of the drawings, the location of the panel mounted fuse holders 58 is such that their association with a particular pair of output terminals is clearly apparent, thus facilitating identification of a burnt-through fuse, in use of the device.

Referring now to Figures 4 and 5 of the drawings, an alternative arrangement of the device 30 as shown in Figures 2 and 3 is schematically illustrated and is designated by the numeral 70. The electrical distribution device 70 particularly has a strip connector including four pairs of input terminals and four pairs of contact terminals located on each side thereof. Insofar as the features of the arrangement of the device 70 for the remainder are clearly apparent, and/or speak for themselves, these are not described further herein.

It will be appreciated that the electrical distribution devices 30 and 70 are completely pre-wired devices which can be effectively sealed once mounted on a support surface and which provide for connection of wire conductors thereto on the operative outside thereof. It is thus ensured that tampering with internal wiring cannot occur. It will be understood in this regard also that the exact configuration of the electrical distribution device of the invention is greatly variable, both in relation to the configuration of the housing structure thereof and in relation to the configuration of the electrical components and parts thereof, in terms of their location with respect to the housing structure and in terms of the wiring of these components and parts with respect to one another.

Claims (15)

1. An electrical distribution device, which includes a housing structure having walls that define an enclosed space, at least a part of at least one wall being displaceable to provide access into the enclosed space; a pair of input terminals located on the housing structure in a configuration in which the incoming power supply from the secondary side of a transformer can be connected thereto from the outside of the housing structure; and at least two pairs of output terminals located on the housing structure in a configuration in which each pair of output terminals can be connected to the respective conductors of a low voltage powered sub-circuit from the outside of the housing structure, the terminals of the pair of input terminals being connected to corresponding terminals of each pair of output terminals by wiring operatively housed in the housing structure.

2. An electrical distribution device as claimed in Claim 1, in which the walls of the housing structure define a rectangular box-like structure.

3. An electrical distribution device as claimed in Claim 1 or Claim 2, in which the pair of input terminals forms part of a connector having contacts, electrically connected to the respective input terminals, to which the incoming power supply from the secondary side of a transformer can be connected to thereby be connected to the input terminals, the pair of input terminals being located on the inside of the housing structure and the contacts being located on the outside of the housing structure.

4. An electrical distribution device as claimed in anyone of the preceding claims, in which the pairs of output terminals form part of at least one terminal block in the form of a strip connector that is securely located on a wall of the housing structure, with the pairs of output terminals being located on the inside of the housing structure and pairs of contact terminals of the strip connector being located on the outside of the housing structure, each pair of contact terminals providing for connection of the respective conductors of a low voltage powered sub-circuit thereto and thereby connection to a pair of output terminals.

5. An electrical distribution device as claimed in Claim 4, in which the pairs of output terminals form part of two terminal blocks in the form of strip connectors securely located on a wall of the housing structure.

6. An electrical distribution device as claimed in any one of the preceding claims, which includes at least one electrical fuse that is operatively connected between the pair of input terminals and one of the pairs of output terminals, in line with the live terminals of the respective pairs of terminals.

7. An electrical distribution device as claimed in Claim 6, which includes an electrical fuse that is operatively connected between the pair of input terminals and each pair of output terminals in line with the live terminals of the respective pairs of terminals.

8. An electrical distribution device as claimed in Claim 7, in which the electrical fuses have the same rating.

9. An electrical distribution device as claimed in Claim 7, in which at least some of the electrical fuses have different ratings to accommodate different requirements.

10. An electrical distribution device as claimed in anyone of Claims 6 to 9, in which each electrical fuse is located in a space defined in a panel mounted fuse holder which is mounted on a wall of the housing structure in a configuration in which the fuse holder is disposed partially on the outside of the housing structure and partially on the inside of the housing structure, the portion of the fuse holder disposed partially on the outside of the housing structure including a removable screw cap that provides for replacement of a fuse located in the space defined in the fuse holder.

11. An electrical distribution device as claimed in Claim 10, in which the arrangement of the panel mounted fuse holders on a wall of the housing structure is such that the line between the input terminals and the output terminals within which each fuse is operable is clearly apparent in relation to the arrangement of the output terminals with respect to the housing structure.

12. An electrical distribution device as claimed in any one of the preceding claims, in which the housing structure is configured to be mounted on a support surface by securing one wall of the housing structure to the support surface, at least a part of the remaining walls of the housing structure been displaceable from the said wall in order to provide access to the enclosed space defined by the housing structure.

13. An electrical distribution device as claimed in anyone of the preceding claims, in which the housing structure is formed of a synthetic plastics material.

14. An electrical distribution device as claimed in anyone of the preceding claims, in which the pair of input terminals and each pair of output terminals are associated with markings applied on the housing structure to indicate to which terminals live and neutral conductors must be connected, for use of the device.

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15. An electrical distribution device substantially as described in the specification with reference to and as illustrated in the accompanying drawings. DATED THIS 30™ DAY OF NOVEMBER 2004 ADAMS & ADAMS APPLICANTS PATENT ATTORNEYS