AU727632B2 - Electrical utility box - Google Patents

Description

1 Regulation 3.2

AUSTRALIA

PATENTS ACT, 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant: Actual Inventor: Address for service in Australia: Invention Title: PDL HOLDINGS LIMITED DAVID LANGMAN COOK A J PARK SON, Level 11, 60 Marcus Clarke Street, Canberra ACT 2601 ELECTRICAL UTILITY BOX The following statement is a full description of this invention, including the best method of performing it known to me/us -2- This invention relates to electrical utility boxes sometimes identified as junction boxes or switch boxes. The invention also relates to a method of assembling electrical utility boxes.

Electrical utility boxes used to house electrical components in an electrical installation, for example a domestic or commercial installation, have in the past been provided by a fabricated or moulded box and attached lid to define and secure in use the electrical fittings and installed wiring.

It is usual for electrical utility boxes to be required in a range of sizes. For moulded boxes the die costs to produce required dies to accommodate the range of utility.boxes is considerable.

It is an object of the present invention to provide an electric utility box and a method of assembling an electrical utility box which has a modular construction and can be produced by assembling common components with some variable parts to provide a range of different sized 13 utility boxes.

0 0 000 0 In accordance with a first aspect of the present invention, there is provided a method of 0. assembling an electrical utility box including the following steps: assembling a body of the electrical utility box by: providing two end members; providing a carcass having two edges which are engageable with respective ones of the end members, by selecting the carcass from 0000 a range of carcasses of various edge-to-edge dimensions; and providing on the carcass, mounting means for electrical fittings; providing a front of the electrical utility box, which corresponds to the dimensions of the body, the front having an aperture with a lid disposed 000 to removably cover the aperture, the location of the aperture corresponding to the location of the mounting means.

Preferably, the range of carcasses comprises a first carcass having a base dimension and other carcasses each of which has a dimension corresponding to the base dimension of a magnitude which is a different multiple of the magnitude of the base dimension. As such, the method of assembling the electrical utility box may include the further step of moulding each of the range of carcasses from a die having two die end portions and a die intermediate portion, by using the same two die end portions for the moulding of all of the carcasses in the range and using a different die intermediate portion for each carcass in the range.

It will be understood that "assembling" as used in the context of the present invention means the bringing together of the various parts and not limited to the carcass, the end portions and the front being fully fitted together. The two end members, the carcass and the front may be provided in kit form.

Preferably, the end members are moulded. In a preferred form of the invention, the method further includes the step of moulding each of the two end members from the same die. The carcass may be channel shaped.

The front may be assembled from two front side members and two front end members, by selecting the front side members from a range of front side members of different lengths. The front may be assembled with one or more substantially identical infill members by determining the number of infill members according to the length of the front side members.

The or each infill member preferably incorporate the aperture. The front side members may 10 comprise rails.

0*S@ o SIn accordance with a second aspect of the present invention, there is provided an electrical utility box including: a body assembled from two end members and a carcass having two edges which are engageable with respective ones of the end members, the carcass having been 15 selected from a range of carcasses of various edge-to-edge dimensions and being provided with mounting means for electrical fittings; and a front corresponding in dimensions to the S body, the front having an aperture with a lid disposed to removably cover the aperture, the location of the aperture corresponding to the location of the mounting means.

Preferably, the end members are moulded. More preferably the end members have frangible portions for cabling. Further, the end members may have a peripheral flange for flush mounting of the box against a wall surface. In one preferred embodiment of the invention, the 0O0 0* 0 end members have integrally formed support means for terminal blocks.

0 25 Advantageously, each of the two edges and its associated end member have complementary engagement means. The carcass is preferably channel shaped.

Preferably, the front includes two front end members and two front side members, the front side members having been selected from a range of front side members of different lengths.

The front may further include one or more substantially identical infill members, the number of infill members determined according to the length of the front side members. The or each infill member may incorporate the aperture.

Preferably, the front side members comprise rails. In a preferred form of the invention, each outer edge of the carcass and the adjacent edges of the two end members have locking tabs ,--dning an elongate gap therebetween in which one of the rail members is received.

-4- With this construction the incremental size in the utility box may be determined according to the edge-to edge dimension of modular infill panels.

This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

One preferred form of the invention will now be described with reference to the 15 accompanying drawings in which; Figure 1 is an exploded view of the body of a utility box designed to be surface mounted on a wall or similar support surface; Figure 2 is an exploded view of the body of a modified utility box suitable for flush mounting; 20 Figure 3 is an exploded view of a front panel and lid of a utility box which may be used on either embodiment of the body; Figure 4 is an exploded view of an alternative form of a front panel which may be used on either embodiment of the body; Figure 5 is an assembled view of the front panel of figure 4; 25 Figure 6 is a detailed view of figure 5; and Figure 7 is a perspective view of the front panel of figure 4 in assembled configuration together with a lid.

The electrical utility box is made up of a body 1 as shown in figure 1 or l a as shown in figure 2 and a front panel 30 and lid 31 as shown in figure 3 or the front panel 30a as shown in figures 4 to 6. The present invention allows the utility box to be assembled from a number of standard components with some variable components allowing a range of different sizes of utility boxes to be produced depending upon the user's requirements.

The body 1 of the utility box as illustrated in figure 1 has been designed for surface mounting and is made up of two moulded end caps 2 desirably each formed from the same mould. The shape of the end mouldings is designed to allow ready access for cabling and to this end, push out sections 3 are provided which allow the desired number of apertures to be formed in the moulding for cabling to enter and leave the utility box. The end caps are also designed to support the junction blocks 6. Blocks 4 are incorporated in the end cap 2 and are designed to support a terminal block or busbar mounting member Normally the junction block 6 or busbar connection will only be provided at one end of the completed body.

In figure 2 the end moulding 2a has an inclined face 7 with knock out panels 8 to allow the entry of cabling. The shape of the moulding 2a is designed to receive the terminal blocks 6a without the separate mounting. Thus the terminal blocks 6a are mounted directly in place on the support rib 9 in the end 2a. The end 2b is shown as a modified end with a similar inclined face 7 for the knock out panels but this end does not need to have the support ribs and mountings 9 for the terminal blocks.

As will be apparent, the design of the end caps can be varied provided the features necessary for convenience in installing componentry in the utility box are preserved and the options for surface mounting or flush mounting are also recognised. The end caps 2a and 2b have ribs 10 which abut against the cladding in the flush mounted model.

The other major component of the body is a carcass 11 which is a channel shaped carcass having opposite edges which correspond to engage with the end caps. This is desirably achieved by providing tongues 12 at the top edges of the carcass. The tongues are shaped to engage through the underside of apertures 13 in the end caps 2a,2b. The carcass 11 may be plain as illustrated in figure 1 for surface mounting or have included therein access points by knock out sections 14 as shown in Figure 2 for flush mounting.

Once the tongues 12 have been engaged in the apertures 13, the end caps are moved relative to the carcass to bring the base 15 of the carcass into engagement with the base 16 of the end caps. In the embodiment illustrated in Figure 1, four tongues 17 have been illustrated to engage in apertures 18. In the embodiment in Figure 2, two tongues 17a engage within the apertures 18a. The operating mode however is similar. Once the end caps are in position relative to the carcass they are held in place by a fixing screw 19.

While the means of attaching the end covers to the carcass is particularly convenient and structurally secure, other means of attachment could be provided, for example, by a greater utilisation of fixing screws.

It is also desirable for the body 1 in either configuration to have in place, means to receive electrical fittings. Thus mounting blocks 20 are provided which can engage within -6apertures 21. A clip-in form of engagement is desirable. The blocks 20 support a rail 22.

Preferably the rail 22 is shaped with the ends 23 arranged to engage in slots 24 in the blocks. The rail ends are pushed into engagement with the blocks 20 and when in place the blocks are pressed to clip into engagement in the carcass. This forms an easy means of assembly and in use forms a robust support for fittings such as fuses or switches 25 that are supported on the rail 22. In fact, the length of the switch components will have a bearing on the edge-to-edge dimension of the carcass.

The utility box may be completed by a front panel 30 and a lid 31 as shown in figure 3.

The front panel 30 is made up of two mouldings 32, again preferably each formed from the same mould. These mouldings are connected together by rails 33. The length of the rail will be selected to correspond with the selected carcass 11 so that an appropriate sized front is produced for the assembled body. A moulded infill panel 34 is supported on the :15 rails and has an aperture 35 through which may protrude the switches of fuses mounted on the rail 22.

00 With this type of configuration the smallest utility box would be provided with one infill panel but if a larger utility box was required two or more infill panels would be provided 20 with further rails 22. The modular sizes would thus be dependent upon the number of infill panels. While this is a preferred form of the invention it would be possible for the Sofront panels to be produced without using the modular infill panels as above described.

ooo 0 0• The lid 31 is a fabricated component to suit the size of utility box and is hingably engaged 25 with the assembled body and front panel.

Figure 4 illustrates an alternative form of a front panel 30a. As with the front panel the front panel 30a comprises two mouldings 32a and a moulded infill panel 34a.

Preferably, each of the two mouldings 32a are formed from the same mould. The mouldings 32a abut against opposite edges of the infill panel 34a and are joined in that disposition by two rails 33a. As can be seen from figure 4, each of the rails 33a extends across each of the three moulded components at adjacent outer edges of each of the moulded components.

The length of the rails 33a will be selected to correspond with the edge-to-edge dimension of the selected carcass so that a front panel of an appropriate size will be produced for the assembled body.

-7- The moulded infill panel 34a also includes an aperture 35a through which may protrude the switches of fuses mounted on the rail 22.

Figures 5 and 6 illustrate more clearly the nature of the connection made between the rails 33a and each of the moulded components 32a, 34a. Each of the mouldings 32a are provided with blocks 40a against the sides of which one end of each of the rails 33a abut.

Upright tabs 42a are also arranged in spaced aligned configuration at the outer edges of the infill panel 34a. Locking upright tabs 44a are also moulded on the infill panel 34a, each of which is aligned with the space between the three upright tabs 42a. The locking tabs 42a are spaced from the upright tabs 42a by an amount sufficient to permit each rail 33a to fit therebetween. At each adjacent edge of the mouldings 32a, further locking tabs 44a are also provided which align with the locking tabs 44a on the infill panel 34a.

It can be seen from figure 5 that in the assembled configuration, each of the rails 33a :15 passes between the aligned locking tabs 44a on the one side and the aligned upright tabs 42a on the other side. The blocks 40a provided on each of the mouldings 32a are also aligned with the upright tabs 42a on the other side of the rail 33a. As can be more clearly seen from the detailed view in figure 6, each of the locking tabs 44a includes a detent :*:portion 45a. Each of the locking tabs 44a has resilience and flexibility which allows the 20 locking tab 44a to flex as the rail 33a is pushed past the detent portion 45a. Once the rail 33a is inserted into place, the detent portion 45a prevents movement of the rail 33a out of the gap between the tabs 42a, 44a.

o:oo• Tenons 47a are also used to prevent longitudinal sliding movement of the rails 33a. As 25 can be seen from figure 4, each end of each of the rails 33a is provided with a slot 48a "which receives a respective tenon 47a. The assembled joint is shown most clearly in figure 6. Each of the tenons 47a are configured as part of the block 40a and are integrally moulded with the mouldings 32a.

Figure 7 shows the front view of the front panel 30a in assembled configuration. As with the previous embodiment, the front panel 30a has a central aperture 35a through which may protrude the switches of fuses mounted in the body 1/l a.

The front panel 30a also includes raised edge portions 48a on opposite side edges of the front panel 30a. A lid 3 la is received within the raised edged portions 48a so that the top surface of the lid 3 la is flush with the top surface of the raised edge portions 48a. The lid is comprised of two portions 51la and 52a. Each portion 51la, 52a is moulded with two pins on opposite side edges on respective ends of the lid 3 la. Each pin 53a engages in a -8complementary recess 54a provided on the front panel Further, adjacent each pin is a small detent 56a moulded into the side edge of the lid portion 5 1a/52a which engages with a corresponding slot 57a in the front panel 30a. The engagement of the detent 56a in the slot 57a maintains the lid portions 51 a/52a in closed configuration.

A further feature of the lid portions 5 la and 52a is the arrangement of rebate portions which are symmetrical about the meeting point of the two lid portions. These rebated portions 60a facilitate hand gripping of the lid portions 5 1a/52a to enable the user to open the lid portions 5 la/52a and access the switches of fuses mounted in the body.

It will therefore be seen from the above description that with standard dies to produce the end moulds for the body and the panel front the die costs are reduced and the size of utility 15 box required can be produced selecting and assembling the components as described with the variable components allowing the range of different sizes in the utility box to be S. accommodated.

Claims (28)

1. A method of assembling an electrical utility box including the following steps: assembling a body of the electrical utility box by: providing two end members; providing a carcass having two edges which are engageable with respective ones of the end members, by selecting the carcass from a range of carcasses of various edge-to-edge dimensions; and providing on the carcass, mounting means for electrical fittings; providing a front of the electrical utility box, which corresponds to the dimensions of the body, the front having an aperture with a lid disposed to removably cover the aperture, the 0 location of the aperture corresponding to the location of the mounting means. 0 0 •00oo 15

2. The method as claimed in claim 1 wherein the range of carcasses comprises a first carcass :0:0 having a base dimension and other carcasses each of which has a dimension corresponding 0 to the base dimension of a magnitude which is a different multiple of the magnitude of the base dimension. ]Q

3. The method as claimed in claim 2 further including the step of moulding each of the range of carcasses from a die having two die end portions and a die intermediate portion, the moulding being performed by using the same two die end portions for the moulding of all of the carcasses in the range and by using a different die intermediate portion for each carcass in the range.

4. The method as claimed in any one of the preceding claims wherein the two end members, the carcass and the front are provided in kit form.

The method as claimed in any one of claims 1 to 3 wherein the twvo end members, the carcass and the front are provided fully fitted together.

6. The method as claimed in any one of the preceding claims wherein the end members are moulded.

7. The method as claimed in any one of the preceding claims further including the step of .,,igulding each of the two end members from the same die.

8. The method as claimed in any one of the preceding claims wherein the carcass is channel shaped.

9. The method as claimed in any one of the preceding claims further including providing a plurality of apertures in the front and providing a corresponding number of mounting means on the carcass aligned with said apertures.

The method as claimed in any one of the preceding claims further including the step of assembling the front from two front side members and two front end members, by selecting the front side members from a range of front side members of different lengths. s

11. The method as claimed in claim 10 further including the step of assembling the front with *0 one or more substantially identical infill members by determining the number of infill 00000 members according to the length of the front side members. 000 0•

12. The method as claimed in claim 10 or claim 11 wherein the front side members comprise rails.

13. The method as claimed in claim 11 or 12 wherein the or each infill member incorporates 0000 0"2G one said aperture. 0 0 0900 S

14. An electrical utility box including: a body assembled from two end members and a carcass having two edges which are engageable with respective ones of the end members, the carcass having been selected from 25 a range of carcasses of various edge-to-edge dimensions and being provided with mounting .0 means for electrical fittings; and a front corresponding in dimensions to the body, the front having an aperture with a lid disposed to removably cover the aperture, the location of the aperture corresponding to the location of the mounting means.

The electrical utility box as claimed in claim 14 wherein the end members are moulded.

16. The electrical utility box as claimed in claim 15 wherein the end members have frangible portions for cabling.

17. The electrical utility box as claimed in claim 15 or 16 wherein the end members have a hpehe ral flange for flush mounting of the box against a wall surface. -11-

18. The electrical utility box as claimed in claim 17 wherein the end members have integrally formed support means for terminal blocks.

19. The electrical utility box as claimed in any one of claims 14 to 18 wherein each of the two edges and its associated end member have complementary engagement means.

The electrical utility box as claimed in any one of claims 14 to 19 wherein the carcass is channel shaped.

21. The electrical utility box as claimed in any one of claims 14 to 20 wherein a plurality of apertures are provided in the front and a corresponding number of mounting means are S provided on the carcass aligned with said apertures.

22. The electrical utility box as claimed in any one of claims 14 to 21 wherein the front' n includes two front end members and two front side members, the front side members having been selected from a range of front side members of various lengths.

23. The electrical utility box as claimed in claim 21 or 22 wherein the front further includes 20. one or more substantially identical infill members, the number of infill members determined according to the length of the front side members.

24. The electrical utility box as claimed in claim 23 wherein the or each infill member incorporates one said aperture.

25. The electrical utility box as claimed in any one of claims 22 to 24 wherein the front side members comprise rails.

26. The electrical utility box as claimed in claim 25 wherein each outer edge of the carcass and the adjacent edges of the two end members have locking tabs defining an elongate gap therebetween in which one of the rail members is received.

27. The electrical utility box substantially as hereinbefore described with reference to the accompanying figures.

28. A method of assembling an electrical utility box substantially as hereinbefore described r Rreference to the accompanying figures. Dated this] Day of/2000 By their Patent Attorneys A J PARK SON On be_ fifo )Arlpcant Pe:, K