NZ585631A - A plastic connector for splicing together two sections of a wire mesh cable tray - Google Patents

Abstract

Disclosed is a cable tray connector which includes a body formed of plastics material. The body has a pair of parallel slots formed in a base surface of the body. Each slot in use receives a wire element of a wire mesh cable tray. The connector also includes a keeper plate adapted to co-operate with the base surface to close the slots, and means for retaining the keeper plate against the base surface.

Description

PATENTS FORM 5 Our Ref: 952624NZ PATENTS ACT 1953 Dated: 26 May 2010 COMPLETE SPECIFICATION A cable tray connector We, Cable Accessories (Australia) Pty. Ltd., an Australian company, ACN 002 184 616, of 8 Distribution Place, Seven Hills, New South Wales, 2147, Australia, 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: 0013E<2732484_1 ):IRG 1 la A CABLE TRAY CONNECTOR Technical Field The present invention relates to the field of electrical cable support systems, and in particular relates to a cable tray connector for joining cable trays.

Background of the Invention Cable trays are known for neatly supporting multiple electrical cables over extended distances. Cable trays are available in various different forms, including in sheet metal form or wire mesh form. Various different forms of connector have also previously been proposed for connecting individual lengths of the various forms of cable trays.

Wire mesh cable tray manufacturers have exploited various avenues for improvement of metallic connectors, with an emphasis on connectors that do not rely on the use of bolts. Different applications of cable trays have very specific requirements. Cable trays used for supporting low voltage distribution cables require the use of metallic connectors so as to provide an earth path to the tray system as specified in various local wiring rules. Cable trays made of specific metallic materials, particularly stainless steel as used in the food industry, require any metallic connector to be formed of the same material so as to avoid sacrificial corrosion. In other applications there is a requirement for colour coding so as to readily identify the types of cables located in the cable trays, and hence metallic connectors need to be powder-coated at significant expense.

All of these multiple and varying requirement for different applications of wire mesh cable trays results in the need for relatively extensive and expensive inventories of different types of cable connectors.

Object of the Invention It is the object of the present invention to substantially overcome or at least ameliorate the above disadvantage.

Summary of the Invention The present invention provides a cable tray connector comprising: a body formed of plastics material, said body having a pair of at least substantially parallel slots formed in a base surface of said body, each said slot for receiving a wire element of a wire mesh cable tray; AH22(2727204 l):PRW a keeper plate adapted to co-operate with said base surface to close said slots; and means for retaining said keeper plate against said base surface.

Typically, said means comprises a bolt extendable through an aperture provided in each of said body and said keeper plate and an associated nut threadingly engageable with said bolt.

In one form, said body is provided with two said pairs of slots, said pairs of slots being mutually substantially perpendicular.

Typically, one of said pairs of slots has a greater depth than the other of said pairs of slots.

Preferably, said body is provided with at least one projection extending from said base surface for engaging an associated recess in said keeper plate for locating said keeper plate with respect to said housing.

Typically, said body is provided with two said projections, located at opposing longitudinal ends of said base surface.

In a preferred form, said body is formed of a fibre reinforced plastics material.

Typically, said fibre reinforced plastics material is glass reinforced nylon.

Typically, said keeper plate is formed of plate metallic material.

In one form, said keeper plate is formed of steel plate material.

In another form, said steel plate material is stainless steel.

In one form, said keeper plate is zinc plated.

Brief Description of the Drawings Preferred embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings wherein: Figure 1 is an exploded isometric view of a cable tray connector according to a first embodiment; Figure 2 is an isometric view of the cable tray connector of Figure 1; Figure 3 is a plan view of the cable tray connector of Figure 1; Figure 4 is an inverse plan view of the cable tray connector of Figure 1; Figure 5 is an end elevation view of the cable tray connector of Figure 1; Figure 6 is a side elevation view of the cable tray connector of Figure 1; Figure 7 is a fragmentary isometric view of a cable tray connection utilising the cable tray connector of Figure 1; AH22(2727204 1):PRW 3 Figure 8 is an isometric view of a cable tray connector according to a second embodiment; Figure 9 is an fragmentary isometric view of a cable tray connection utilising the cable tray connector of Figure 8; Figure 10 is an isometric view of a cable tray connector according to a third embodiment; Figure 11 is a fragmentary isometric view of a cable tray connection utilising the cable tray connector of Figure 10.

Detailed Description of the Preferred Embodiments Referring to Figures 1 through 6 of the accompanying drawings, a cable tray connector 100 according to a first embodiment comprises a body 101, keeper plate 102, bolt 103 and nut 104.

The body 101 is formed of plastics material that may conveniently be formed of 15 a fibre reinforced plastics material such as glass reinforced nylon. The body 101 is typically integrally moulded. The body 101 has a first pair of at least substantially parallel slots 105 in a base surface 106 of the body 101. The first pair of slots 105 each extend across the lateral extent of the base surface 106 between the opposing side surfaces 107 of the body 101. The first pair of slots 105 are sized so as to receive 20 laterally extending end wires 2 of a pair of adjacent mesh cable trays 1 as depicted in Figure 7. The first pair of slots 105 are typically spaced about 20 to 30 mm apart so as to leave an equivalent gap between the two cable trays 1 being connected.

A second pair of at least substantially parallel slots 108 is formed in the base surface 106. The second pair of slots 108 extends substantially perpendicular to the first 25 pair of slots 105 along the longitudinal extent of the base surface 106 between opposing end surfaces 109 of the body 101. As depicted in Figure 7, the second pair of slots 108 are sized and spaced so as to receive the two outermost longitudinally extending wires 3 forming a side wall of each of the cable trays 1. These wires 3 are typically spaced about 25 mm apart. Given that the laterally extending wires 2 of the cable tray 1 here overlap 30 the longitudinally extending wires 3, the first pair of slots 105 are deeper than the second pair of slots 108 so as to allow for accommodation of both pairs of wires 2, 3. An aperture 110 extends through the thickness of the body 101 on to the base surface 106 for receipt of the shaft of the bolt 103. The body 101 is provided with two projections in the form of tabs 111 located at each longitudinal end of the base surface 106. It is envisaged, 35 however, that a single projection might alternately be provided.

AH22(2727204 1):PRW The keeper plate 102 is typically a flat plate that may be formed of any of various materials, depending upon the application. For applications where an earth path is required between adjacent cable trays 1, the keeper plate 102 would typically be formed of metallic plate material. In such applications where the cable trays 1 are formed of stainless steel, the keeper plate 102 will typically be formed of stainless steel plate material. For other applications with steel cable trays, the keeper plate 2 will typically be formed of plate steel material, and where the steel cable tray is zinc plated, the keeper plate 102 will also typically be zinc plated so as to avoid sacrificial corrosion. For applications where an earth path is not required, such as specific fibre optic applications, the keeper plate 102 might be formed of plastics material. The keeper plate 102 is configured to co-operate with the base surface 106 so as to close the slots 105, 108.

When wires 2, 3 of the cable trays 1 are located in these slots 105, 108 as depicted in Figure 7 and the keeper plate 102 is located over the base surface 106, the wires are locked within the respective slots. To assist in locating the keeper plate 102 in relation to the base surface 106, recesses 112 are formed in each end of the keeper plate 102 for engaging the projections 111 of the body 101. An aperture 113 is provided in the centre of the keeper plate 102. The keeper plate 102 can be inexpensively punched from raw plate material.

The bolt 103 and nut 104 form a means for retaining the keeper plate 102 against the base surface 106 and are operated in the usual manner to lock the keeper plate 102 in position against the base surface 106, thereby locking the wires 2, 3 of the cable trays 1 in position so as to form a rigid connection between the cable trays 1. By retaining both the laterally extending wires 2 and outermost longitudinally extending wires 3 of the cable trays 1, the connection formed is load bearing and can be formed mid-span between cable tray supports.

By forming a common body 101 for all applications and a simple, inexpensive, keeper plate 102 formed of various materials for different applications, relatively inexpensive inventories can be maintained to cover various applications.

Given that the longitudinally extending wires 4 of cable trays 1 that are formed in the base of the cable tray 1 are typically spaced approximately 50 mm apart, rather than 25 mm apart for the outermost wires 3, a cable connector 200 according to a second embodiment is provided, as depicted in Figure 8. Features of the cable connector 200 that are identical or equivalent to those of the cable connector are labelled with the same reference numerals, increased by 100. The cable connector 200 of the second embodiment is identical to the cable connector 100 of the first embodiment described AH22(2727204 1):PRW above, except that the body 201 and keeper plate 202 are broader, with the second pair of slots 208 being spaced further apart, here 50 mm to match the spacing of the longitudinally extending wires 4.

A cable connector 300 according to a third embodiment is depicted in Figures 10 and 11. Features of the cable connector 300 that are identical or equivalent to those of the cable connector 100 have reference numerals increased by 200. The cable connector 300 of the third embodiment is identical to the cable connector 100 of the first embodiment, except that it has a somewhat narrower body and omits the second pair of slots. This cable connector 300 is particularly suitable for joining non-collinearly aligned cable trays when making minor alignment or curve adjustments in a connected array of cable trays. Given that the cable tray connector 300 only connects one pair of wires 2, it is generally non-load bearing.

AH22(2727204 l):PRW

Claims (13)

I/WE CLAIM:

1. A cable tray connector comprising: a body formed of plastics material, said body having a pair of at least substantially parallel slots formed in a base surface of said body, each said slot for receiving a wire element of a wire mesh cable tray; a keeper plate adapted to co-operate with said base surface to close said slots; and means for retaining said keeper plate against said base surface.

2. The connector of claim 1, wherein said means comprises a bolt extendable through an aperture provided in each of said body and said keeper plate and an associated nut threadingly engageable with said bolt.

3. The connector of either one of claims 1 and 2, wherein said body is provided with two said pairs of slots, said pairs of slots being mutually substantially perpendicular.

4. The system of claim 3, wherein one of said pairs of slots has a greater depth than the other of said pairs of slots.

5. The system of any one of claims 1 to 4, wherein said body is provided with at least one projection extending from said base surface for engaging an associated recess in said keeper plate for locating said keeper plate with respect to said housing.

6. The connector of claim 5, wherein said body is provided with two said projections, located at opposing longitudinal ends of said base surface.

7. The connector of any of claims 1 to 6, wherein said body is formed of a fibre reinforced plastics material.

8. The connector of claim 7, wherein said fibre reinforced plastics material is glass reinforced nylon.

9. The connector of any one of claims 1 to 8, wherein said keeper plate is formed of plate metallic material. AH22(2727204 1):PRW 7

10. The connector of claim 9, wherein said keeper plate is formed of steel plate material. 5

11. The connector of claim 10, wherein said steel plate material is stainless steel.

12. The connector of claim 10, wherein said keeper plate is zinc plated. io

13. A cable tray connector substantially as hereinbefore described in relation to Figures 1 to 7, Figures 8 and 9, or Figures 10 and 11 of the accompanying drawings. Cable Accessories (Australia) Pty Ltd By the Attorneys for the Applicant SPRUSON & FERGUSON Per: AH22(2727204 l):PRW