AU2006230765A1

AU2006230765A1 - Cable connection device

Info

Publication number: AU2006230765A1
Application number: AU2006230765A
Authority: AU
Inventors: Bruce James Ogden
Original assignee: CABLE ACCESSORIES AUSTRALIA PT
Current assignee: CABLE ACCESSORIES (AUSTRALIA) PTY Ltd
Priority date: 2005-10-25
Filing date: 2006-10-23
Publication date: 2007-05-10
Anticipated expiration: 2026-10-23
Also published as: AU2006230765B2

Description

S&FRef: 785352

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT In \o t\ Cc,

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Name and Address of Applicant Actual Inventor(s): Address for Service: Invention Title: Cable Accessories (Australia) Pty. Ltd., an Australian company, ACN 002 184 616, of 26 Derby Street, Silverwater, New South Wales, 2128, Australia Bruce James Ogden Spruson Ferguson St Martins Tower Level 31 Market Street Sydney NSW 2000 (CCN 3710000177) Cable connection device Associated Provisional Application Details: [33] Country:

AU

[31] Appl'n No(s): 2005905900 [32] Application Date: 25 Oct 2005 The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5845c

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SCABLE CONNECTION DEVICE 0 Field of the Invention 0 Cc The present invention relates to the field of cable connection devices, and particularly relates to, but is not limited to, a cable connection device for connecting an electrical power distribution house service cable to a consumer power cable.

INO Background of the Invention 0 Overhead electrical distribution mains house service cables provide mains electrical power from overhead power cables running along a street to individual

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Sconsumer buildings. These service cables are typically formed of single insulated XLPE C 10o aluminum conductors of various sizes, but typically not greater than 35 mm 2 in cross sectional area for electrical distribution authorities in Australia. This service cable is connected to a consumer or house side cable, typically at or adjacent the roof edge of the house or other building to which electricity is to be supplied. The consumer cable is typically either a single or double insulated stranded copper conductor of up to 25 mm 2 in cross sectional area.

A current form of cable connection device for forming the connection between the service cable and the consumer cable, typically referred to as a house service connector, is in the form of a conductive aluminum block having a single tunnel extending therethrough, forming a cable entry point at each end of the tunnel. One end of the tunnel is specifically configured to receive the aluminum service cable, bearing a series of teeth in the tunnel wall for piercing the insulation of the insulated service cable.

The opposing end of the tunnel has a smooth wall to accept the end of a stranded consumer cable that has been stripped of its insulation. Shear head bolts extend through the aluminum block into each opposing end of the tunnel so as to directly contact the cable located in each end of the tunnel.

At the service cable end, as the shear head bolt is tightened, the leading end of the shear head bolt drives the insulator cable into the insulation piercing teeth so as to make the required electrical connection, and further tends to tear out the insulation so as to provide some electrical connection between the aluminum conductor and the shear held bolt itself. At the consumer cable end, the shear head bolt bears against the bare stranded copper conductor, providing a pressure based electrical connection between the copper conductor, the aluminum block and the shear head bolt. The heads of the shear head bolts shear off when the predetermined required torque, and resultant pressure application, is achieved.

[R:\LIBLLJI91 2 These types of house service connectors suffer various problems including one Sof non-reversibility whereby care must be taken to ensure that the correct cable is inserted in the correct end of the connector, otherwise an inadequate or non-existent electrical connection will be provided. The connector also only provides a single electrical contact point for each cable, whereas multiple contact points are preferred to ensure the integrity IND of the electrical connection. The connector also provides no ability to confirm the quality of the electrical connection. Other problems include poor water sealing capability of the i house service connector, and potential corrosion resulting from water ingress and contact between dissimilar metals in the connection.

N 10 Object of the Invention It is the object of the present invention to overcome or substantially ameliorate at least one of the above disadvantages.

Summary of the Invention The present invention provides an electrical cable connection device comprising: a first clamp portion having a first clamping face; a second clamp portion having a second clamping face, said second clamping face opposing said first clamping face; a fastener extending between said first clamp portion and said second clamp portion and operable to draw said first clamping face toward said second clamping face; and a detent extending between said first clamping face and said second clamping face to inhibit relative movement of said first clamping face towards said second clamping face, said detent being displaceable from between said first clamping face and said second clamping face upon application of compressive force between said first clamping face and said second clamping face by operation of said fastener.

Typically, said connection device includes two said detents extending along opposing sides of said first clamp portion and said second clamp portion, said detents being arranged such that, upon application of said compressive force, said detents are urged outwardly from between said first and second clamping faces.

Typically, said detents each comprise an elongate detent member having opposing elongate detent faces defining a tapered cross section and each adapted to engage an edge of a respective one of said first clamping face and said second clamping face upon application of said compressive force.

The tapered cross section may be a semicircular cross section.

(R:\LIBLLI191 3 c Said connection device may further comprise a housing within which said first Sclamp portion and said second clamp portion are received.

Said detents may be formed integrally with said housing.

The said housing may comprise: a first wall extending across said first clamp portion, IO a second wall extending across said second clamp portion, two opposing side walls each extending between said first wall and said second wall adjacent a respective said side of said first clamp portion and said second clamp

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portion, 1- 0 an end wall, and an opening opposing said end wall and communicating with said tunnels for receipt of two electrical cables, said detents being integrally formed with said side walls.

The end wall of said housing may be light transmissive.

Typically, said first clamping face and said second clamping face are each provided with two longitudinally extending recesses each for receipt of an electrical cable, said recesses of said first clamping face opposing said recesses of said second clamping face so as to define two tunnels.

Each of said recesses may be provided with a plurality of teeth for piercing cable insulation.

The connection device may include two said fasteners.

Typically each of said fasteners extends between said tunnels.

The first clamp portion may comprise two separate clamp elements, each extending between said opposing sides of said first clamp portion, one of said fasteners extending through each of said clamp elements.

The housing may be encapsulated in a waterproofing material.

The waterproofing material may be silicon rubber.

The first clamp portion may be pivotable relative to said second clamp portion.

Brief Description of the Drawings A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings, wherein: Fig. 1 is a front elevation view of a cable connection device.

Fig. 2 is a plan view of the cable connection device of Fig. 1.

Fig. 3 is an inverse plan view of the cable connection device of Fig. 1.

[R:\LIBLLJI 9115-spcei.doc:KEH 4 0 Fig. 4 is an enlarged fragmentary front elevation view of the cable connection Sdevice of Fig. 1 with the first and second clamp portions separated.

Cc Fig. 5 is an enlarged fragmentary front elevation view of the cable connection 0 device of Fig. 1 with the first and second clamp portions drawn together.

Fig. 6 is a front perspective view of the housing of the cable connection device of IND Fig. 1.

Fig. 7 is a fragmentary rear perspective view of the housing on Fig. 6.

I Fig. 8 is a front elevation view of the cable connection device of Fig. 1 including an encapsulating water proofing membrane.

N 10 Fig. 9 is a plan view of the cable connection device of Fig. 8 with two connected cables.

Detailed Description of the Preferred Embodiments Referring particularly to Figs 1 to 3, an electrical cable connection device includes a first clamp portion 2 having a first clamping face 3 and a second clamp portion 4 having a second clamping face 5. The second clamping face 5 opposes the first clamping face 3 to enable the clamping of two electrical cables therebetween. Each of the first and second clamping faces 3, 5 is provided with two longitudinally extending semicircular recesses 6, 7. The recesses 6 of the first clamping face 3 oppose the recesses 7 of the second clamping face 5 so as to define tunnels 8 between the clamping faces 3, 5 for receipt of the cables. Each of the recesses 6, 7 are here provided with a plurality of teeth 9 for piercing plastic cable insulation. The first and second clamp portions 2, 4 will be formed of a conductive material, typically structural aluminium that is copper plated and then tin plated so as to provide a bi-metallic joint.

As best depicted in Fig. 2, the first clamp portion 2 is here in the form of two separate clamp elements 2a that each extend between opposing sides of the first clamp portion, one forming the front half and one forming the rear half of the first clamp portion 2. Both recesses 6 extend along the two clamp elements 2a. The first clamp portion 2 may, however, be in the form of a single element only.

The second clamp portion 4 is provided with two threaded apertures extending through its thickness onto the second clamping face 5, located between the recesses 7. Each of the clamp elements 2a of the first clamp portion 2 is provided with a laterally extending slot 11 located between the recesses 6 and aligned with the threaded aperture 10 of the second clamp portion 4. Threaded fasteners 12 extend between the first and second clamp portions 2, 4 by way of the slots 11 and threaded aperture 10. One [R:\LIBLL] 19115-speci.doc:KEH fastener 12 extends through each of the clamp elements 2a of the first clamp portion 2, O however where the first clamp portion 2 is in the form of a single clamp element only, a

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single-fastener may be utilized.

The fasteners 12 each have a shoulder 13 located between the fastener head 14 and the threaded fastener shaft 15. As each fastener 12 is threadingly advanced through IDthe threaded aperture 10, the fastener shoulder 13 bears against the upper surface of the rclamp element 2a so as to draw the clamp portions 2, 4 toward each other. Accordingly, ¢€3 the first and second clamping faces 3, 5 are gradually drawn together with operation of the two fasteners 12. The slots 11 are sized to enable free passage of the shaft 15 of the i0o fastener 12 therethrough. The lateral elongation of the slots 11 enables the clamp elements 2a of the first clamp portion 2 to pivot or rock in relation to the second clamp portion 4. The upper face of each of the clamp elements 2a of the first clamp portion 2 is convexly curved such that engagement of the fastener shoulders 13 with the upper surface of the clamp elements 2a will not inhibit pivoting/rocking of the clamp elements 2a.

The fasteners 12 will generally be shear head bolts, such that the fastener heads 14 shear off at a predetermined torque which ensures that a desired compressive load is applied between the first and second clamping faces 3, 5. Where a fastener without a shear head is employed, the shoulder 13 of the fastener 12 may be dispensed with, such that the fastener head itself bears against the upper surface of the clamp element 2a.

The cable connection device 1 further includes two detents 16 which each extend between the first clamping face 3 and the second clamping face 5 so as to inhibit relative movement of the first clamping face 3 towards the second clamping face 5. Here the detents 16 extend along opposing sides of each of the first clamp portion 2 and second clamp portion 4. The detents 16 are configured to be displaceable from between the first clamping face 3 and the second clamping face 5 upon application of compressive force to the detent 16, between the first clamping face 3 and second clamping face 5, by operation of the fasteners 12. The detents 16 ensure that the first and second clamping faces 3, remain separated prior to operation of the fasteners 12 for ease of location of the cables between the first and second clamping faces 3, 5, and particularly within the tunnels 8.

Without the detents 16, the first and second clamping faces 3, 5 would tend to rest against each other, inhibiting location of the cables within the tunnels 8. Whilst the use of two detents 16 is depicted in the accompanying drawings, it is envisaged that a single detent only might be suitable in alternative configurations.

IR:\LIBLLI91I 6 ,I The detents 16 are specifically in the form of elongate detent members 16 which Shave opposing elongate faces 16a, 16b which define a tapered cross section, here Cc specifically a semicircular cross section.

The detents 16 are integrally formed with the side walls 18 of a housing 17 within which the first clamping portion 2 and second clamping portion 4 are received.

IND The housing 17 is depicted in further detail in Figures 6 and 7. The housing 17 comprises a first (upper) wall 19 extending across the first clamp portion 2, a second (lower) wall I extending across the second clamp portion 4, the opposing side walls 18 each extending between the upper and lower walls 19, 20, a rear end wall 21 and an opening 22 opposing I 10 the rear end wall 21. Holes 23 are provided in the upper wall 19 for receipt of the fasteners 12.

As best depicted in Figure 4, the upper face 16a of each detent 16 is adapted to engage a side edge of the first clamping face 3, with the lower face 16b of each detent 16 adapted to engage a side edge of the second clamping face 5. As the first and second clamping faces 3, 5 are drawn together by way of the fasteners 12, a compressive force is applied to each detent 16 by way of engagement of the detent tapered detent faces 16a, 16b with the edges of the clamping faces 3, 5. This compressive force applied to the tapered cross section of the detents 16 tends to urge the detents outwardly from between the first and second clamping faces 3, 5. Flexing of the side walls 18 of the housing 17 accommodate the outward displacement of the detents 16, as depicted in Figure The housing front opening 22 communicates with the tunnels 8 to enable receipt of the cables within the tunnels 8. The rear wall 21 of the housing 17 may be light transmissive, and preferably transparent, to serve as a means for visual inspection of a cable connection completed within the cable connection device 1. The entire housing 21 would typically be formed of a transparent plastic material.

As depicted in Figures 8 and 9, the entire housing 17 may be encapsulated in a waterproofing material forming a waterproofing shroud 24. The waterproofing shroud 24 would typically be formed by over-moulding a silicon rubber material. Cable entry ports defining cable entry apertures 26 aligned with the tunnels 8, are formed in the front of the waterproofing shroud 24. The cable entry apertures 26 are typically formed with a slightly smaller diameter than that of the insulation of the cables 100 so as to form a generally watertight seal. Similarly, watertight fastener entry ports 27 are formed in the top of the waterproofing shroud 24 for entry of the fasteners 12. The rear of the waterproofing shroud 24 is provided with an opening (not depicted) so as to enable visual (R:\LIBLL]I911 7 inspection through the transparent rear wall 21 of the housing 17. The waterproofing O shroud 24 generally provides protection to the electrical connection formed within the connection device 1 from the elements and particularly from moisture which may otherwise result in corrosion of the cables.

In operation, two electrical cables 100 to be connected are inserted through the INO cable entry apertures 26 of the cable entry ports 25 and into the tunnels 8 defined between the first and second clamp portions 2, 4. For connection devices 1 incorporating the cable IC piercing teeth 9 within the tunnels 8, there is no need to strip any insulation from the cables 100, however where cable piercing teeth 9 are not provided it will be necessary to ri io first strip the cables 100. Location of the cables 100 within the tunnels 8 is confirmed by viewing through the transparent rear wall 21 of the housing 17.

The two fasteners 12 are then driven by way of a socket or other appropriate drive head so as to draw the clamping faces 3, 5 toward each other, thereby engaging the insulation piercing teeth 9 with the cable insulation and compressing the cables between Is the recesses 6, 7 of the first and second clamping faces 3, 5. As the first and second clamp portions 2, 4 are drawn closer together, the detents 16 are urged outwardly from between the clamping face 3, 5 so as to allow the clamping faces 3, 5 to be drawn together. As the piercing teeth 9 pierce the insulation of the cables 100, electrical connection is made between the conductors of the cables 100 and the teeth 9. Once a predetermined torque applied to the fasteners 12 is reached, typically approximately 13Nm, the fastener heads 14 shear off, leaving the cables 100 firmly clamped between the first and second clamp portions 2, 4. The integrity of the connection is then again visually checked through the transparent rear wall 21 of the housing 17. When cables of differing diameter are being connected, the pivotability of the clamp elements 2a of the first clamp portion 2 enables an equal clamping force to be applied to the dissimilar sized cables, such that the differing sized cables can be located in either of the tunnels 8 and a consistent clamping force is still achieved.

The connection provided by the cable connection device 1 provides two separate areas of pressure contact between each cable and the first and second clamp portions 2, 4.

The pressure applied to the cables is also by way of a direct application of compressive force by opposing clamping face 3, 5, which will not tend to tear the strands of a stranded cable, as opposed to application of force by the leading end of a rotating fastener which may tear the strands, as is the case with various prior art cable connection devices.

(R:\LIBLL1191 5-specidoc: KEH

Claims

2. The connection device of claim 1, including two said detents extending along opposing sides of said first clamp portion and said second clamp portion, said detents being arranged such that, upon application of said compressive force, said detents are urged outwardly from between said first and second clamping faces.
3. The connection device of claim 2, wherein said detents each comprise an elongate detent member having opposing elongate detent faces defining a tapered cross section and each adapted to engage an edge of a respective one of said first clamping face and said second clamping face upon application of said compressive force.
4. The connection device of claim 3, wherein said tapered cross section is a semicircular cross section. The connection device any one of claims 1 to 4, further comprising a housing within which said first clamp portion and said second clamp portion are received.
6. The connection device of claim 5 wherein said detent(s) is/are formed integrally with said housing.
7. The connection device of either of claim 5 and 6 wherein said housing comprises: a first wall extending across said first clamp portion, a second wall extending across said second clamp portion, two opposing side walls each extending between said first wall and said second wall adjacent a respective said side of said first clamp portion and said second clamp portion, [R:\LIBLLI9115-spccidocKEH 9 San end wall, and O an opening opposing said end wall and communicating with said tunnels for receipt of two electrical cables, Ssaid detents being integrally formed with said side walls.
8. The connection device of claim 7, wherein said end wall of said housing IDis light transmissive.
9. The connection device of any one of claims 1 to 8, wherein said first I clamping face and said second clamping face are each provided with two longitudinally extending recesses each for receipt of an electrical cable, said recesses of said first S l0o clamping face opposing said recesses of said second clamping face so as to define two tunnels. The connection device of claim 9, wherein each of said recesses is provided with a plurality of teeth for piercing cable insulation.
11. The connection device of any one of claims 1 to 10, including two said fasteners.
12. The connection device of claim 11, wherein each of said fasteners extends between said tunnels.
13. The connection device of any one of claims 1 to 12, wherein said first clamp portion comprises two separate clamp elements, each extending between said opposing sides of said first clamp portion, one of said fasteners extending through each of said clamp elements.
14. The connection device of any one of claims 5 to 8, wherein said housing is encapsulated in a waterproofing material. The connection device of claim 14, wherein said waterproofing material is silicon rubber.
16. The connection device of any one of claims 1 to 15, wherein said first clamp portion is pivotable relative to said second clamp portion. [R:\LIBLL]I91 IO
17. An electrical cable connection device, substantially as hereinbefore O described with reference to the accompanying drawings. 0 Dated 24 October, 2006 SCable Accessories (Australia) Pty. Ltd. s Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON [R:\LIBLL)19115-speci.doc:KEH