A number of methods of fixing such edge strip protectors to the electrode edges have been utilized in the past. Traditionally edge strip protectors have been drilled to accept plastic pins that are located through a series of holes formed down the vertical side edge regions of the electrode plate. These pins are then either glued or ultrasonically welded into position in an endeavour to seal them and prevent electric current leakage through the penetrations. The disadvantage of this method, apart from the complexity of manufacture and assembly, is that copper nodules grow on the edge strips in the vicinity of the pins. Moreover, the drilling of the edge strip weakens the plastic material that in time leads to premature product failure.

In an alternative method, see for example Australian Patent Specification No. 75360/91 (646450), a series of holes are punched down the sides of the cathode plate, into which pegs or pins are placed. The edge strip protector is then formed with an internal cavity that locates over these pins thus retaining the edge strip protector against lateral movement away from the electrode edge. The edge strip protector is then typically drilled through to accept a top pin which retains the edge strip against vertical movement relative to the electrode plate.

While this arrangement works satisfactorily, the multiple hole punchings and the assembly of pins or pegs therethrough add to the manufacturing difficulty and cost.

A still further method is described in US Patent Specification Nos. 5470450 and 5549801 (Tanaka et al) and 5368714 (Perlich et al). These methods utilize a wedge piece to maintain a positive grip on the electrode plate through a leverage arrangement. In practice, the elevated temperatures experienced within an electrolytic refining tank, cause the plastic materials, over time, to take up a permanent"set"and the edge strip loses its gripping effectiveness. Thus

refineries utilizing this method of attachment, find it necessary to install pneumatic pushers to relocate the edge strip protectors in position on the edges of the electrode plates.

A still further prior art disclosure is provided in US Patent No. 3830710 where the electrode plate is provided with notched corners at its upper and lower side edge corners with an edge strip protector made of elastic material being stretched between the upper and lower side edge notched corners and retained thereon by operation with the notched corner formations. This arrangement has the advantage of simplicity of construction but unfortunately, it is not practical to use materials that are sufficiently elastic to be installed in this manner in the conditions of use in an electrolysis metal deposition tank. That is to say elastic materials will not perform the required function over a sufficiently long period of time to make them commercially viable for the intended use.

Accordingly, the objective of the present invention is to provide an edge strip protector that may be connected to the edges of an electrode plate in a simple and effective manner which will also operate effectively in use. The invention also aims at providing a novel and useful combination of an edge strip protector with an electrode plate.

Accordingly, the present invention provides an electrode plate in combination with an edge strip protector formed from a rigid insulating material, the electrode plate having an edge zone with said edge strip protector having a longitudinally extending groove into which said electrode plate edge zone is located, a portion of said edge zone including a notch region having an undercut portion, the edge strip protector having an engagement formation co-operable with the undercut portion of the notch region whereby when the edge strip protector is assembled with said electrode plate, said one end of the edge strip protector is prevented from moving either laterally away from the electrode edge plate and in a first direction parallel to said electrode plate edge zone, and fastener means spaced from the notch region and the cooperating engagement formation retaining said edge strip protector to the electrode plate edge zone.

The rigid insulating material may be a plastics material suitable for use in an electrolysis tank used for electrolytic refining of metals.

In one preferred embodiment, the corner of the electrode plate including the notch region is preferably located in a lower edge of the electrode plate, however, it should be appreciated that it might also be located at the upper end of the electrode plate or at any position between the upper and lower ends of the electrode plate.

Preferred features and aspects of the electrode plate in combination with at least an edge strip protector may be as defined in claims 4 to 16 annexed hereto, which claims are hereby made part of the disclosure of this specification.

In accordance with another aspect, the present invention also provides an edge strip protector for an electrode plate formed from a rigid insulating material, the edge strip having a longitudinally extending groove adapted in use to fit over an electrode plate edge zone with an engagement formation located within said groove with an abutment zone adapted to engage with an abutment edge formed on an edge region of the electrode plate whereby when the abutment zone and the abutment edge are engaged, said edge strip is prevented from moving laterally away from said electrode plate or from moving in a first direction along said electrode plate edge zone. The rigid insulating material may be a plastics material suitable for use in the environment of an electrolysis tank.

Preferably, the edge strip protector at one end may be free of any engagement formation as defined above and may include fastener receiving means such as a bore or the like, suitably spaced from the engagement formation adapted, in use, to receive a fastener member that is also engagable with the electrode plate edge zone.

Preferred features of this further aspect may be as defined in claims 18 to 26 annexed hereto, which claims are by this reference thereto hereby made part of the disclosure of this specification.

Preferred embodiments of the present invention will hereafter be described with reference to the accompanying drawings, in which: Fig 1 is a perspective view of an electrode plate together with edge strip protectors connected to the upright side edges of the electrode plate ; Fig 1 A is a detailed view of the area marked A in Fig 1; Fig 2 is a detailed perspective view of a lower corner region of the electrode plate and installed edge strip protector shown in Fig 1;

Fig 3 is an exploded view of the parts making the assembly shown in Fig 2; Fig 4 is a longitudinal section view in perspective of the assembly shown in Fig 2; Fig 5 is a face elevation view of further preferred embodiment of a side edge strip mounted to an electrode plate ; Fig 6 is a view similar to Fig 5, partially in section; Fig 7 is an exploded perspective view of the edge strip and electrode plate shown in Fig 5; and Fig 8 is an assembled perspective view of the parts shown in Fig 7.

Referring to the drawings, Fig 1 shows an assembly 10 including an electrode plate 11 secured to and depending from a conductor bar 12 as is known in the art. The electrode plate 11 may be a cathode plate conveniently made from stainless steel, however any other metal suitable for use in an electrolysis process might also be used. The electrode plate 11 may include upper apertures 13 to enable the assembly to be picked up and positioned as desired by fork lift handling equipment, typically in stacks involving multiple numbers of electrode plates. At least the upright side edges of the electrode plate 11 have edge strip protectors 14 connected thereto as will be described in greater detail with reference to Figs 2 to 4.

The edge strip protectors 14 conveniently are made from a relatively rigid plastics material that have appropriate mechanical, abrasion resistance wear and electrical insulating characteristics for the intended use. The preferred embodiment illustrated may be a two part construction having an outer member 15 and an inner gasket member 16. It is, however, believed that the arrangement will work without the inner gasket member 16. In the illustrated construction, the outer member 15 includes a longitudinally extending groove 17 adapted to receive the gasket member 16 therein. The outer member 15 is intended to be relatively rigid and the inner gasket member 16 may be made of a relatively resilient or elastic rubber or plastics material.

At the lower end of the edge strip member 15 a closed end formation 18 is provided, the formation 18 defining an inclined abutment surface 19 effectively closing the lower end of the groove 17. The abutment surface 19 conveniently makes an angle greater than 90° with the longitudinal direction of the edge strip

protector and is complementary to an end closure web 20 of the inner resilient gasket member 16. The inner surface of the end closure web 20 is conveniently complementary to the angled edge 21 formed on the corner notch 22 in the lower end of the electrode plate 11. This arrangement is such that, once installed, the edge strip protector 14 cannot move upwardly along the edge zone 23 of the electrode plate and the end 18 of the edge strip protector 14 cannot move laterally away from the edge zone 23 in the direction of arrow 24 (Fig 2). As shown in Fig 3, the end formation 18 may include a shallow groove 25 to locate the upright edge 26 of the corner notch 22.

The members 15 and 16 of the edge strip protector 14, may be extruded from suitable plastics or elastomeric materials with the end formations 18 and 20 being moulded thereon. Alternatively the members 15 and 16 may be fully moulded from suitable materials.

The upper end of the edge strip protectors 14 may be secured to the electrode plate 11 by means of a fastener 27 passed through appropriately formed apertures in the edge strip protector 14 and the edge zone 23 of the electrode plate. The fastener 27 may be a rivet made from any suitable materials including stainless steel. Other fasteners such as screws and bolts might also be used. In one preferred embodiment, the fastener may be of an elastomeric material that will allow for very small movements of the edge strip protector relative to the electrode plate without causing major damage to either during handling operations.

Reference will now be made to Figs 5 to 8 of the annexed drawings which illustrate an alternative preferred embodiment. In this embodiment, a notch region 22 is not formed in either a lower or an upper corner 30 of the electrode plate 11 but rather a recessed region 22 is provided in the edge zone 23 between the lower and upper ends of the electrode plate 11. The recessed region 22 has a longitudinally extending recessed zone 31 forming an undercut zone inwardly of an oppositely extending tab portion 32 of the electrode plate 11. The recessed region 22 has a relatively wide or open mouth 33 which allows an engagement formation 34 within the groove 17 in the edge strip protector 14 to enter the recessed zone 31 with a simple lateral movement. Once the engagement formation 34 disposed within the groove 17 is inserted into the recessed zone 31,

the edge strip protector 14 can be slid in a longitudinal direction (arrow A) relative to the electrode plate 11 to the position illustrated in Figs 5 and 6 where the inter engagement of the leg 35 of the engagement formation 34 in the recessed zone 31 prevents further movement in direction A and also prevents lateral movement of the edge strip protector 14 laterally away from the electrode edge zone 23. In this position, a bore 36 in the edge strip protector coincides with a bore 37 in the electrode plate at a position spaced from the engagement formation 34 to enable a fastener 27 such as a rivet, screw or the like to be inserted. Any features described above in relation to the embodiment shown in Figs 1 to 4 might also be used in association with the embodiment shown in Figs 1 to 5. Other modifications within the scope of the claims as annexed may also be used. For example, two or more engagement formations 34 might be provided spaced along the edge protector, each co-operating with a respective said recessed zone 31. A still further possible embodiment is to provide one or more recessed zones 31 along the intermediate regions of the edge zone 23 in addition to a corner notched region 22. It may, for example, also be possible to provide a recessed zone 22,31 at or adjacent one corner of the electrode plate with a second recessed zone 31 located adjacent to but not at the other corner of the electrode plate with the fastener receiving formations 36,37 being located at an intermediate position along the edge zone 23. Such an arrangement might also include one or more recessed zones 31 being positioned along the edge zone 23 of the electrode plate 11. Those skilled in the art will recognize other possible modifications that might also be used.