NZ260196A - Domestic meter box: cables may be laid into box through open side - Google Patents

Description

260 '96 NEW ZEALAND PATENTS ACT, 1953 No.: 260196 Date: 28 March 1994 COMPLETE SPECIFICATION IMPROVEMENTS IN/OR RELATING TO ELECTRICAL JUNCTION BOXES AND/OR METHODS OF WIRING DOMESTIC INSTALLATIONS We, VYNCO INDUSTRIES NZ LIMITED, a New Zealand company, of 388 Tuam Street, Christchurch, New Zealand, hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- 0196 'This invention relates to electric junction boxes and/or methods of wiring domestic or similar capacity installations.

Daring the erection of a new house or other domestic dwelling, the wiring runs are laid in piace before the cladding is erected. The cable runs radiate from an electrical junction box to which the supply is connected.

With known designs of junction boxes, the cables have to enter the box through cable grommets or sleeves. Also some components of the junction box are pre-fitted in place and these can be targets for theft before the wiring is completed.

It is an object of the present invention to provide means of placing the ends of cable runs in a junction box ready for termination and a method of completing cable terminal connections in the junction box which will minimise the abovementioned disadvantages or which will provide the public with a useful choice.

Accordingly the present invention consists in an electrical junction box comprising a casing having a back and walls defining a space in which cable termination may be made, one wall or a significant section of one wall being omitted to allow cables to be laid into the box through this area, an earth and neutral bar assembly engageable with the casing to extend across the space left in the wall of the casing and in use is adapted to support an earth and neutral bar for earth and neutral termination of the cables.

In a further aspect the present invention consists in a method of wiring an electrical junction box comprising the steps of: fitting a casing in place having a base and walls defining a space for cable termination with one wall or a significant section of one wall omitted; laying the cable runs with the ends of the cables to be terminated finishing in the junction box and entering the junction box through the omitted wall or section of wall; fitting an earth and neutral bar assembly in the space through which the cables enter the junction box; completing the wiring of the junction box with the earth and neutral terminal bar supported on the earth and neutral bar assembly.

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

One preferred form of the invention will be described in which: Figure 1 is a perspective view of a junction box according to the present invention with the earth and neutral bar assembly omitted; 260196 Figure 2 is a detail of the top of the junction box and the earth and neutral bar assembly shown separated; Figure 3 is a detail in three isometric projections showing the earth and neutral bar assembly fitted in place; and Figure 4 is a detailed cross-section through the earth and neutral bar assembly.

In a preferred form of the invention, a junction box 1 is fabricated from a suitable material, preferably a plastics material, to have a generally rectangular configuration with a base 2, a bottom wall 3 and side walls 4 and 5. Return flanges 6 are provided at the top edge of the base 2 and of the side walls 4 and 5. Otherwise the top of the junction box is omitted. A mounting feature 7 is provided in the back of the box and return flanges 8 are provided on the front face of the box to receive the front panel of the completed junction box 1.

An earth and neutral bar assembly 9 is arranged to engage in the top of the junction box 1. The earth and neutral bar assembly 9 is illustrated in Figure 4 and detail of the earth and neutral bar assembly in place is illustrated in Figure 3.

The earth and neutral bar assembly 9 preferably is a section having a top 10 with two weakening grooves 11 and 12 on the lower surface thereof. The two weakening grooves 11 and 12 enable the section beyond the weakening grooves to be snapped off on installation. A shaped arm projects from the lower surface of the top 10 with a step 14 and an incline section 15 arranged in use to provide the mounting surface for the earth and neutral bar (not shown).

Mounting lugs 16 are located on the side walls 4 and 5 so that a mounting screw passing through the arm 13 will engage in the mounting lugs 16 to fasten the earth and neutral bar assembly in place.

In use the junction box 1 is fitted in place in the installation to be wired without the earth and neutral bar assembly. Cable runs are brought to the junction box casing with the cable ends laid in place. They may conveniently be looped around the mounting feature 7. The installation remains in this condition until the wiring is- ready to be completed.

When wiring is ready to be completed the earth and neutral bar assembly is fitted in place with the sections beyond the weakening grooves 11 or 12 being snapped off if necessary depending upon the amount of cabling to be terminated in the box. This provides a neat shape around the entering cables to ensure that there is an appropriate seal provided on the top of the junction box. e earth and neutral bar is mounted on the arm of shaped section 15 and the earth and neutral bar connections terminated in this bar.

The remaining electrical equipment for example miniature circuit breakers and other required fittings can be wired in place in the junction box on the front panel which will be attached to the front of the casing. A top is provided also of suitable plastics material.

In the preferred embodiment of the present invention the junction box has been shown with the top omitted. However it will be appreciated that the invention may be produced to operate with a side wall omitted or if there was some special reason even allowing a significant section of one of the walls to be omitted.

The present invention has a number of advantages. Once the junction box casing 1 has been fitted in place it is very easy for the ends of the cable run to be placed in the box and when so located there is no equipment in the junction box casing that would tempt theft.

The junction box according to the present invention allows the wiring to be completed with the installation of the neutral bar assembly in an effective and efficient manner. i i » r

Claims (8)

WHAT WE CLAIM IS: 260196

1. An electrical junction box comprising a casing having a back and walls defining a space in which cable termination may be made, one wall or a significant section of one wall being omitted to allow cables to be laid into the box through this area and an earth and neutral bar assembly engageable with the casing to extend across the space left in the wall of the casing and in use is adapted to support the earth and neutral bar for earth and neutral termination of the cables.

2. A junction box as claimed in claim 1 wherein the casing is rectangular with the top wall omitted and the side walls including mounting rests for the earth and neutral bar assembly.

3. An electrical junction box as claimed in claim 1 or claim 2 wherein the earth and neutral bar assembly has one or more sections which in use may be removed to adjust the width of the assembly.

4. An electrical junction box as claimed in claim 3 wherein the earth and neutral bar is an extruded member with one or more weakening grooves enabling the section beyond the weakening grooves to be snapped off.

5. An electrical junction box as claimed in any one of the preceding claims incorporating an arm projecting from the undersurface, in use said arm providing the mounting for the earth and neutral bar.

6. An electrical junction box when constructed, arranged and operable substantially as herein described with reference to the accompanying drawings.

7. A method of wiring an electrical junction box comprising the steps of fitting a casing in place having a base and walls defining a space for cable termination with one wall or a significant section of one wall omitted; laying the cable runs with the end of the cables to be terminated finishing in the junction box and entering the junction box through the omitted section of wall; fitting an earth and neutral bar assembly in the space through which the cables enter the junction box; completing the wiring of the junction box with the earth and neutral terminal bar supported on the earth and neutral bar assembly.

8. A method as claimed in claim 7 wherein the earth and neutral bar assembly is reduced in width depending upon the number of electrical cables entering the junction box. « « > r 260196 A method of wiring an electrical junction box when performed substantially as herein > described with reference to any example thereof. DOTED THIS IO^WDAY OFlT^AovcK A.J. PARK & SON PER AGENTS FOR THE APPLIGANTSL