S&F Ref: 952637 AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name and Address Cable Accessories (Australia) Pty. Ltd., of Applicant: an Australian company, ACN 002 184 616, of 8 Distribution Place, Seven Hills, New South Wales, 2147, Australia Actual Inventor(s): Bruce James Ogden Address for Service: Spruson & Ferguson St Martins Tower Level 35 31 Market Street Sydney NSW 2000 (CCN 3710000177) Invention Title: Seal arrangement of a cable connection device Associated Provisional Application Details: [33] Country: [31] Appl'n No(s): (32] Application Date: AU 2009902736 15 Jun 2009 The following statement is a full description of this invention, including the best method of performing it known to me/us: 5845c(2733958_1) SEAL ARRANGEMENT OF A CABLE CONNECTION DEVICE Technical Field The present invention relates to the field of electrical cable connection devices, 5 and particularly relates to a seal arrangement of such a device. Background of the Invention Underground electrical distribution networks generally provide electrical power to individual consumer buildings by way of one of two methods. In one method, 10 electrical distribution mains house service cables project above the ground surface into aboveground connection pillars where consumer cables supplying individual consumer buildings are connected to the service cable within the aboveground pillar. Whilst such aboveground pillars are often considered to be unsightly, they do provide easy access and protection fro the cable terminations located aboveground. is Another method locates the entire distribution system underground with distribution connections located in underground pits typically formed of either plastic or cement. In such a system, the main service cables, which are typically 240 volt four core cables, are kept intact as a continuous cable extending past each of the distribution pits in any given street. A tap off cable is then connected to the main service cable by way of an 20 IDC (insulation displacement connector) connector encased in resin so as to protect the connection from the underground environment, particularly protecting the connector from water ingress. The tap off cable then projects into a distribution pit where it is connected to one or more consumer cables for supplying electrical power to individual consumers. It is common for the distribution pits to fill with mud and water. Accordingly, it is 25 important to isolate the connection from water ingress in light of both safety concerns and maintenance of the electrical connection. Current submersible pit connectors are typically encased in a housing with cable ports for passage of electrical cables into the connector and sealable fastener access ports providing access for fasteners operable to secure the cables within the connectors. These 30 sealable ports are provided with caps that are removed for access to the fasteners and then replaced so as to seal the port. It is quite common, however, for these sealable ports to leak.
2 Object of the Invention It is the object of the present invention to substantially overcome or at least ameliorate the above problems. 5 Summary of the Invention In a first aspect, the present invention provides a seal arrangement of a cable connection device comprising: an access port wall defining the periphery of an access port having a longitudinal axis, said access port wall having an inner face and an outer face each extending to substantially parallel to said longitudinal axis and an end face extending between said outer face and said inner face; and a removeable cap adapted to seal said access port, said cap having: a cap wall with an outer face extending substantially parallel to said longitudinal axis and adapted to engage said inner face of said access port wall about the periphery of is said access port; a skirt spaced from and extending about said cap wall, said skirt having an inner face extending substantially parallel to said longitudinal axis and adapted to engage said outer face of said access port wall around the periphery thereof, and a rim joining said skirt to said cap wall and adapted to engage said end face of 20 said access port wall. Typically, said outer face of said cap wall and said inner face of said access port wall are each provided with a series of inter-engaging circumferentially extending ribs. Typically, said access port wall is formed of a compressible material. Typically, said compressible material is an elastomeric material, such as silicone 25 rubber. In a preferred form, said cap is formed of a rigid plastics material. In a preferred form, said access port is provided with a reduced diameter portion, sized such that, in said reduced diameter portion, said inner face of said access port wall engages a fastener of the connection device accessible through said access port. 30 In a second aspect, the present invention provides a cable connection device comprising: a body formed of an electrically conductive material and defining a tunnel for receipt of an electrical cable; a fastener extending through said body into said tunnel for securing the electrical 35 cable to said body within said tunnel; and 3 a waterproofing housing within which said body is received, said housing comprising: a cable entry port communicating with said tunnel for receipt of the electrical cable, said cable entry port being configured to form a seal with the electrical cable; s and a seal arrangement as defined above, said fastener being accessible through said access port of said seal arrangement. Typically, said cable connection device includes at least two of each of said tunnel, said fastener, said cable port and said seal arrangement. 10 Brief Description of the Drawings A preferred embodiment of the present invention will now be described, by way of an example only, with reference to the accompanying drawings wherein: Figure 1 is a cross-sectional front elevation view of a cable connection device; 15 Figure 2 is a cross-sectional front elevation view of a cable connection formed in the cable connection device of Figure 1; and Figure 3 is a side elevation view of the cable connection device of Figure 1; Figure 4 is a plan view of the cable connection device of Figure 1; Figure 5 is a fragmentary cross-sectional front elevation view of the seal 20 arrangement of the cable connection device of Figure 1; Figure 6 is fragmentary cross-sectional front elevation view of the seal arrangement of Figure 5 following establishment of a connection; Figure 7 is a cross-sectional side elevation view of the cable port arrangement of the cable connection device of Figure 1; and 25 Figure 8 is a cross-sectional side elevation view of the cable port cap of the cable port arrangement of Figure 5. Detailed Description of the Preferred Embodiments Referring firstly to Figure 1 of the accompanying drawings, a cable connection 30 device I has a body 2 that is here in the form of two body elements 3 that are arranged side by side and connected by way of a dovetail connection 4. The body 2 could alternatively be formed as a single unitary body, or formed with more than two body elements 3 where connection between more than two electrical cables is desired. Each of the body elements 3 is formed of an electrically conductive material, typically aluminium 35 and tin-plated. Each of the body elements 3 has a tunnel 5 extending along its length for 4 receipt of an electrical cable 100. Two fasteners 6 extend through each body element 3 into the tunnel 5 of the respective body element 3. Whilst two fasteners 6 are provided for each body element 3 so as to provide two points of connection for each electrical cable 100, it is envisaged that a single fastener 6 only might be utilised where desired. s Associated with each fastener 6 is a clamp element 7 located within the respective tunnel 5. Prior to a connection being established, each clamp element 7 is retained in a pre connection position spaced from the lower wall 8 of the respective tunnel 5 by way of a pair of frangible nodes 9, provided along opposing sides of each clamp element 7, engaging a pair of corresponding slots 10 formed in the side walls of the tunnel 5. 10 Retaining the clamp element 7 in the pre-connection position facilitates insertion of the electrical cable 100 into the tunnel 5. An electrical connection between an electrical cable 100 located in the tunnel 5 and the body element 3 is established by driving the head II of each fastener 6 such that the leading end 12 of each fastener 6 engages the clamp element 7. Upon application of a predetermined load from the fastener 6, the frangible is nodes 9 fail, enabling further driving of the fastener 6 to drive the clamp element 7 into engagement with the electrical cable 100 as depicted in Figure 2. The lower wall 8 of the tunnel 5 and lower face of the clamp element 7 are provided with insulation piercing teeth 13 for piercing insulation of the electrical cable 100, to thereby establish an electrical connection with the core of the electrical cable 100. 20 The fasteners 6 are typically shear head fasteners, such that the head 11 shears from the body of the fastener 6, as depicted in Figure 2, once a predetermined torque is applied. The predetermined torque is typically of the order of IONm. A predetermined known clamping force is thus applied to the electrical cable 100 to establish a standard connection. Whilst the connection device has been described with the clamp element 7, it 25 is envisaged that the seal arrangement of the present invention may also be applied to other forms of connection device, including those where the fastener 6 directly engages the electrical cable 100 and the clamp element 7 is omitted. To protect the electrical cable connection from the environment, particularly in underground applications where the cable connection device 1 may be immersed in water, 30 the body is received within a waterproofing housing 50 as depicted generally in Figures 3 and 4. The body 51 of the housing 50 will typically be formed of a compressible waterproofing material and overmoulded onto the body 3. Suitable materials include elastomeric materials such as silicone rubber. Referring now to Figures 5 and 6, the housing 50 defines a seal arrangement 52. The seal arrangement 52 has an access port 35 wall 53 of the housing body 51 that defines the periphery of an access port 54 through 5 which an associated fastener 6 may be accessed. Each access port 54 has a longitudinal axis L and is here generally cylindrical in shape. The access port wall 53 has an annular form within an inner face 56 and outer face 55 extending substantially parallel to the longitudinal axis L. An end face 57 of the access port wall 53 extends between the outer 5 face 55 and inner face 56. A removeable cap 70 of the housing 50 is adapted to seal the access port 54. The cap 70 has a cap wall 71 that is here annular in form and has an outer face 72 that engages the inner face 56 of the access port wall 53 about the periphery of the access port 54. The cap 70 also has a skirt 73 that is spaced from and extends about the cap wall 71. The skirt 73 has an inner face 74 that engages the outer face 55 of the access 1o port wall 53 around the periphery thereof. A rim 75 joins the skirt 73 to the cap wall 71 and engages the end face 57 of the access port wall 53. The cap 70 is typically formed of a rigid plastics material, whilst the access port wall 53, being moulded as part of the housing body 51, is formed of a compressible material, which is typically an elastomeric material such as silicone rubber. Each cap 70 is secured to the housing body 51 by a strap is 76. The cap 70 is removeable for access to the fastener 6 to establish a connection and then subsequently re-fitted to the access port wall 53. The outer face 72 of the cap wall 71 and the inner face 56 of the access port wall 53 are each typically provided with a series of circumferentially extending ribs that inter engage so as to provide a primary seal between the cap wall 71 and the access port wall 20 53. This primary seal effectively acts as a third line of defence against water ingress. A first line of defence is provided by a secondary seal provided between the inner face 74 of the skirt 73 of the cap 70 and the outer face 55 of the access port wall 53. A second line of defence is provided by a tertiary seal provided between the end wall 57 of the access port wall 53 and the rim 75 of the cap 70. The primary seal is longer than each of the 25 secondary and tertiary seals. The skirt 73 tends to lock the cap wall 71 of the cap 70 against the access port wall 53, inhibiting relative displacement of these two walls which would otherwise affect the integrity of the seal. Location of the primary seal defined between the cap wall 71 and access port wall 53 within the access port 54 also protects the integrity of the primary seal from grit and other debris which may be found in the 30 external environment of the cable connection device 1. Such debris might otherwise affect the integrity of a seal that directly communicates with the external environment of the cable connection device, as is the case with various known seal arrangements. A further seal within the access port 54 is defined between a series of circumferentially extending ribs 14 defined on the body of the fastener 6 and a thickened 35 portion 56a of the inner face 56 of the access port wall 53 which defines a reduced 6 diameter portion of the access port 54. As depicted in Figure 6, this further seal is maintained after connection has been established with the fastener 6 fully driven and the shear head removed. The access port 54 may also be filled with grease so as to further inhibit water ingress. 5 Referring now to Figures 7 and 8, the housing 50 has a cable port 58 that communicates with each tunnel 5 of the cable connection device 1. Each cable port 58 is defined by a tubular projection 59 of the housing body 51. The tubular projection has a series of partition seals 60 spaced internally along its length. Each of the partition seals 60 is provided with an aperture 61, with the apertures gradually increasing in size towards to the tunnel 5. This increasing size of the apertures 61 compensates for the increasing difficulty in feeding a cable through successive apertures 61 from the end of the tubular projection 59. The series of apertures 61 will typically be sized to accept a maximum electrical cable size of 95mm 2 , with at least the outermost partition seals 60 engaging the cable 100 as it passes through the respective aperture 61. A cable port cap 80, typically is formed of rigid plastics material, may be fitted over each of the tubular projections 59 so as to seal the cable port 58 when not in use. The cable port cap 80 has a hollow central tube 81 with a locking barb 82 formed on the end thereof. The locking barb 82 and tube 81 pass through the first two apertures 61, with the barb 82 engaging the second partition seal 60. When small electrical cables, up to 25mm 2 , are to be utilised with the cable 20 connection device 1, the barb 82 is removed from the end of the tube 81 and the cable fed through the hollow tube into the cable port 58. Both the outer wall of the tubular projection 71 and the inner wall of the cap 80 are provided with circumferentially extending ribs 62, 83 to improve sealing therebetween. Each cable port 58 will typically be filled with grease. 25 Referring to Figure 3, the housing 50 is also provided with a window 84 at the end of each tunnel 5 opposing the cable entry port 58 for viewing of individual connections within each tunnel 5. A person skilled in the art will appreciate that the sealing arrangements described will be readily applicable to various forms of cable connection devices.