Field of the Invention

The invention concerns a device for joining two or more metal components together via a joint; a process for joining two or more metal components together via a joint comprising the use of said device; and a kit of parts for joining two or more metal components together via a joint comprising a plurality of removable contact surfaces adapted to mate with one or more of said different metal components at least in the region of said joint.

Background of the Invention

An earthing system (UK and IEC) or grounding system (US) connects specific parts of an electric power system with the ground, typically the Earth's conductive surface, for safety and functional purposes. The choice of earthing system can affect the safety and electromagnetic compatibility of the installation. In addition to electric power systems, other systems may require grounding for safety or function. Tall structures may have lightning rods as part of a system to protect them from lightning strikes. Telegraph lines may use the Earth as one conductor of a circuit, saving the cost of installation of a return wire over a long circuit. Radio antennas may require grounding for operation, as well as to control static electricity and provide lightning protection. Earthing systems are made of components, such as grounding rods and grounding connectors, that are connected together using a number of processes, most notably by exothermic welding or brazing; both exothermic welding and brazing are different methods by which these components are bonded together.

Exothermic welding- also known as thermite welding or exothermic bonding - is a process that uses the high temperature reaction of copper oxide and aluminium (thermite) within a semi-permanent graphite mould to form electrical connections mainly between copper to copper or copper to steel. A low voltage current is required to initiate the reaction. Once the reaction has started, the process obtains the required welding energy. In this technique, the metal components themselves are melted and fused together. Using this method, a perfect molecular bonding of the conductors is achieved and therefore the electrical proprieties of the conductors at the bond joint are improved. However, the moulds vary depending on application and are very expensive. Furthermore, specialist storage is required for the exothermic materials. In addition, the technique cannot be used in all environments, because it involves the use of acutely toxic materials that are harmful to, e.g., marine animals.

Alternatively, brazing is a welding process in which the metal components to be welded are not melted, instead they are heated up to a very high temperature in order to sandwich therebetween a filler material, which at high temperatures itself melts to form a join. Since the base components remain intact, they are able to retain most of their physical properties and further this process, advantageously, allows the joining of two components made of different metals. Additionally, since the metal components to be joined are not melted during the process, the components retain their original shape; edges and contours are not eroded or changed. Another advantage of brazing is the elimination of stored-up stresses that are often present in fusion welding. This is extremely important in the repair of large castings. This process is currently used in the UK, Ireland and many other countries worldwide, in order to create a permanent joint between two conductive metal components, usually copper or steel.

However, whilst brazing has the above advantages, during the bonding process, in order to achieve the high temperatures needed to melt the filler material, a source of heat (typically a flame torch) is used in combination with a highly volatile mixture of gases, usually propane-acetylene. This means, conventionally, brazing uses a potentially highly flammable and explosive mixes of gases which under pressure may decompose rapidly and, further, on contact with metals in the presence of moisture can form acetylides which are also explosive. Additionally, the bonding of components is more complicated with brazing, thus, requiring much higher levels of training and skill and, as a consequence, the technique is more time consuming and can suffer from greater joint variability, resulting in the end product(s) having a range of physical properties, owing to the differences in the skills of the welder.

Accordingly, we herein disclose an alternative device and process for joining metal components theretogether that eliminates the need for the use of highly inflammable materials, as in exothermic welding, and the use of conventional brazing techniques, thereby vastly improving safety. In addition, the lack of use of flammable gases leads to an eradication of waste gases, removal of acutely toxic materials, and so a reduced impact on the environment. Furthermore, our device and process also reduce inter-user variability, allowing for greater consistency in joint formation and so the production of a consistently better product. Additionally, unlike when joining using other methods in the art and particularly in the context of earth tape joining, the device disclosed herein can achieve a zero resistance join, which is advantageous as it removes the possibility of sparking between joined parts and/or clamps due to build-up of static which poses a fire/explosion risk that is thus avoided with the present device. Finally, by improving the physical and electrical connection properties of a joint and thus removing the need for further fixing devices or the like, one can achieve a better and safer earthing system that reduces the drawbacks of added weight and need for continual maintenance required in other conventional systems.

Statements of Invention

A device for joining two or more metal components together via a joint comprising: i) a clamping member configured to releasably grip the said components, at least in the region of said joint, wherein said clamping member has at least one induction heat-conducting contact surface that is adapted to mate with one or more of said metal components at least in the region of said joint, wherein the clamping member is operationally coupled to at least one urging member whereby force can be applied to the clamping member and transferred to the region of the joint for the purpose of forcing the said components there together; and ii) at least one induction coil positioned adjacent or about the clamping member, or a part thereof, which induction coil is connected to a power supply where, upon supply of power to said induction coil, said induction heat-conducting contact surface is heated; whereby heat sufficient to join said components together via a joint is transferred from the said induction heat-conducting contact surface to the metal components.

As is known in the art, induction heating is a thermal process in which an electrically conductive material is placed within a varying magnetic field and heated via hysteresis (magnetic materials only) and/or an induced electrical current (all conductive materials). The changing magnetic field is generated by an alternating current (AC) being passed through an electrical winding (coil/inductor). When heating a magnetic metal, such as iron, the magnetic particles within its atomic structure - called domains - physically align themselves with the polarity of the magnetic field. As the magnetic field reverses, the domains physically reverse direction. This constant reversing of direction results in internal friction heating. This heating, through magnetic domain switching, is known as hysteresis heating. Hysteresis only occurs in magnetic materials and is the most efficient form of induction heating. It can exceed 90% efficiency. However, this does not occur in non-magnetic materials, which are instead heated by eddy currents. Eddy currents allow electromagnetic induction to heat any electrically conductive material, including gold, copper, silver, aluminum, steel and many others. However, the efficiency of eddy current heating will vary depending on the metal/metal alloy being heated, from 50% to as low as 5% efficiency. This therefore means, unless provided with a very high-power supply, for many metal joint formations, particularly involving low or non-magnetic metals such as copper (which is used in many earthing, and plumbing, applications, but is one of the most difficult metals to heat by induction - in terms of efficiency), induction heating is not a viable option.

Accordingly, reference herein to a joint refers to any region where two or more metal components are physically joined together, typically but not exclusively, this is achieved by melting, brazing, welding, soldering or the like. As will be appreciated by those skilled in the art, a joint may secure together two or more components made of different metals. Further the joint may be a butt or lap joint, and variations thereof. The device disclosed herein can be used in any of the afore applications to form any of the afore joints. All other joints are variations of a butt or a lap joint. Joint design may be influenced by intended use, type of filler metal, flux etc. Components to be joined for subsequent use find application in earthing systems (both domestic and consumer/grid, including Earth tape to earth tape, earth tape to round bar, earth tape to cable lug, Aluminium earthing tape), plumbing, lightning rod conductors, continuous welds in railway manufacture, or the like.

As will be appreciated, in the device disclosed herein, the joining of the metal components is done by heat transfer, specifically by conduction, from the clamping member, which itself is heated via the induction coil. In particular, the clamping member, or at least its induction heat-conducting contact surface, is made of a material that can be readily heated by induction heating (i.e., having a high level of magnetism or being a magnetic metal, such as iron).

Therefore, in a preferred embodiment of the invention, said clamping member or at least its induction heat-conducting contact surface, is at least partially manufactured from a magnetically permeable metal or metal alloy. As is known in the art, magnetically permeable is the measure of magnetization that a material obtains in response to an applied magnetic field, in the present case, from the induction coil. Magnetic permeability is the ability of a material to absorb and retain magnetic flux. The greater the ability to retain flux, the higher the permeability. Non-magnetic materials have a relative permeability of 1 , while a good magnetic material, like iron, has a relative permeability of 5000 (with reference to the International System of Units, Sl-system). In SI units, permeability is measured in henries per meter (H/m), or equivalently in newtons per ampere squared (N/A ² ). Alternatively, permeability is often measured as a relative measure, Relative permeability. The relative permeability is the ratio of the permeability of a specific medium to the permeability of free space pO pr = p / pO (1 ) where pr = the relative permeability p = permeability of the medium (H/m) pO = 4TT 10" ⁷ (H/m) « 1.257 10’ ⁶ (H/m, N/A ² )

The lowest relative magnetic permeability of a paramagnetic material is 1.0 - and the magnetic response of the material is the same as 'free space' or complete vacuum. As it is a relative measure, it has no units.

Preferably, said clamping member, or at least its induction heat-conducting contact surface, is at least partially manufactured from a material having a greater magnetic permeability than the magnetic permeability of, either one or both, the metal components to be joined. More preferably still, said clamping member or at least its induction heat-conducting contact surface is at least partially manufactured from a material having a magnetic permeability selected from the group comprising: 1 ,000-250,000, and every magnetic permeability integer therebetween. Yet more preferably still, said clamping member, or at least its induction heat-conducting contact surface, is at least partially manufactured from a material having a magnetic permeability of at least 5000, still more preferably at least 10,000, more preferably still at least 25,000, and more preferably still at least 50,000.

As mentioned, in order to provide rigidity during heating and also to apply uniform force across the region of the joint, the clamping member is operationally coupled to at least one urging member whereby force can be applied to the clamping member and transferred to the region of the joint for the purpose of forcing the said components there together. Therefore, most preferably, the clamping member is made of a material of sufficient hardness that when a force is applied to same, the clamping member transfers the applied force equally, across induction heat-conducting contact surface, thereby ensuring the formation of a strong and successful joint.

Ideally, the clamping member, or at least its induction heat-conducting contact surface, is manufactured from ferromagnetic and ferrimagnetic materials, more ideally materials selected from the group comprising: iron, nickel, cobalt, manganese, iron or steel, silicon, silicon carbide or alloys or mixtures thereof. Most ideally, the clamping member is silicone carbide, iron or an iron alloy.

Additionally, as will be appreciated by the skilled person, the device of the invention has utility in joining together metal components that have relatively low magnetic permeability, such as but not limited to those materials with a magnetic permeability selected from the group comprising: 1 -500, and every relative permeability integer therebetween. Yet more preferably still, said metal components are manufactured from a material having a magnetic permeability less than 100, still more preferably less than least 50, more preferably still less than 10, and more preferably still less than 5, and most preferably about 1. Such materials include copper, aluminum, steel, nickel, gold, silver, or the like, and alloys thereof.

However, the skilled person will appreciate the components must be made from a material(s) that is/are thermally conductive.

In a further preferred embodiment of the invention, said clamping member is molded to encase, in a mating manner, the metal components to be joined. Thus, in a preferred embodiment, a single induction heat-conducting contact surface is fashioned to encase at least one of the components to be joined, typically this means it comprises at least one space, channel, indentation, recess, or the like, whose shape is complementary to at least a part, usually a half, of the joint between the metal components to be joined. Thus, two opposite contact surfaces provide a recess that accommodates, in the region of the join, the two components when joined together. In this encasing manner, a precise and close mating joint between the components can be made that can withstand, when in use, an applied force across the entire joint. In the absence of this close mating, the joint may subsequently fail.

In certain embodiments a single or both, induction heat-conducting contact surface(s) is/are fashioned to encase, not only the components to be joined, but also a material which sits within, or will sit within, the said joint. Where a filler is to be used in a joint, the amount of space to accommodate same, to form a strong and functional joint, will vary depending on the type of filler to be used, the material of the components and the thermal expansion of all these parts.

Ideally, the shape and/or configuration of the induction heat-conducting contact surface(s) is/are fashioned in a bespoke manner and so manufactured for each particular joint to be made, having regard to the metal components to be joined. As will be appreciated by those skilled in the art, the determination of the shape of the induction heat-conducting contact surface(s) and the clamping member comprising same, can be determined by numerous means known in the art, such as but not limited to 3D computer design and subsequent molding.

In yet a further embodiment, said clamping member comprises an inlet, ideally in fluid communication with the at least one induction heat-conducting contact surface of same, and most ideally in the region of said joint, for delivery of one or more filler agents which, when melted during heating, assist in joint formation. Such agents include, but are not limited to, bonding agents, bonding powders, metal flux agents, solder or the like.

In a further preferred embodiment, said clamping member further comprises an external surface that is adapted to mate with an urging member whereby an external force can be applied to clamp the clamping member about said components. Ideally the external surface and the urging member are substantially planar or flat. More ideally still the urging member is configured to apply a force to all parts of the clamping member or a substantial part of the clamping member.

Therefore, in yet a further preferred embodiment, said device further comprises an urging member, in functional association with the clamping member in order to apply force to same to ensure the metal components mate theretogether for the purpose of being joined.

In yet a further preferred embodiment, said clamping member comprises at least a first and second jaw, ideally cooperative with one another, most ideally hingedly attached to one another and moveable from an open to a closed position. As will be appreciated, in this arrangement, the metal components can be inserted into the clamping member, positioned between the jaws within the at least one induction heat-conducting contact surface, after which the jaws can be closed to encase the metal components prior to the commencement of induction heating and/or the application of a compressive force to manufacture a secure joint. Advantageously, the geometry is fashioned such that a tight complementary fit is provided between the clamping member and the metal components, such that uniform force and heat can be applied.

In yet a further preferred embodiment, said device, ideally said clamping member, comprises a temperature sensor for detecting the temperature of the clamp. More preferably, said temperature sensor is in functional communication with the at least one induction heat-conducting contact surface of said clamping member, ideally the joint region thereof. In this manner, the temperature of the joint region can be determined during the joining process and time allowed for the temperature to reach a level effective to achieve joint formation, but not too high that the metal excessively melts. Preferably, the temperature sensor is in operable communication with the induction coil, most ideally by way of a processor or sensing unit, whereby the processor/sensing unit can control activation/de-activation of the induction coil according to a signal, ideally an electrical signal, received from the temperature sensor. In this way an operator or a program can control the device. In a preferred embodiment, the processor/sensing unit can set a pre-determined temperature threshold, according to the nature of the metal to be joined.

In a further preferred embodiment, said at least one induction coil is positioned adjacent, or about, at least the first jaw and/or second jaw. As will be appreciated, in this manner, either or both jaws of the clamping member can be heated.

As is known in the art, an induction coil is an electrical winding in which AC is passed from a power supply for generating an electromagnetic field of a specific pattern for heating an object. In a preferred embodiment, said induction coil may take any form known in the art, such as but not limited to a helical winding of hollow electrically conductive tubing, a solid rod, a flexible cable, and a machined billet. In a preferred embodiment, said induction coil is manufactured from copper or copper alloy. Copper is the chosen material for fabricating inductors due to its high electrical conductivity (low power losses), high thermal conductivity (easily cooled with water), and relatively low cost. As will be appreciated, the shape, material, and geometry of the induction coil, however, can be determined by one skilled in the art according to the nature of the metals to be joined, their size and dimensions and the joint to be formed.

In a preferred embodiment, said induction coil is positioned about or adjacent at least a part, ideally a substantial part or the entire clamping member. More preferably still, said induction coil or at least a part thereof, ideally the exterior surface, is coated with a heat reflective material. As will be appreciated, this will ensure heat is not lost exteriorly from the clamp and thus heat is effectively redirected towards the internal side of the clamp where the heat can heat the metal components thus reducing heat loss and so improving efficiency. In yet a further preferred embodiment, said induction coil further comprises a magnetic flux concentrator or coating to enhance the magnetic field and thus heating of the clamping member. As is known in the art, flux concentrators improve the efficiency of induction coils by improving the electromagnetic coupling between the workpiece surface, in this case metal components, and the current-carrying region of the induction coil, as well as by reducing stray losses (due to reduced reluctance of the air path). Examples of such flux concentrators include, but are not limited to, ferrous steel, ferrites and ferrite- and iron-based powder materials. As will be appreciated, particularly in embodiments wherein the induction coil is positioned about only a part of the clamping member, such as only the first or the second jaw, use of a flux concentrator permits one to extend the magnetic field to the other jaw thus achieving heating of the other jaw, albeit with reduced power.

In order for the induction coil to produce the electromagnetic field and induce heating in the clamping member, an electrical supply from an associated power supply is required.

Accordingly, in a preferred embodiment, said induction coil is associated with a remote power supply, for example, by way of wiring to a remote energy system.

Alternatively, and more preferably for the purpose of use in remote locations, said device further comprises a power supply, such as a battery or generator, in electrical communication with the induction coil.

As is known in the art, the power required to generate a magnetic field, and so a level of heating for joint formation will vary according to the nature of the metallic components to be joined and the type of joint to be created. Moreover, the level of heating produced by the clamping member will vary according to its size and the material from which it is made. Base metals vary in density, specific heat, electrical resistivity, and relative magnetic permeability as well as other defining characteristics, but these four traits are the most important for calculating power requirements for a process. In a preferred embodiment, said power supply provides a power selected from the group comprising: 1- 50kW and every 0.1 kW therebetween, more preferably 1 -20kW, and every 0.1 Kw therebetween, more preferably still 1 -15kW including every 0.1 kW therebetween. Yet more preferably still, power supply provides a power less than 15kW, still more preferably less than least 10Kw, including 1 kW, 2kW, 3kW, 4kW, 5kW, 6kW, 7kW, 8kW, 9kW, 10kWand every 0.1 kW therebetween. However, advantageously, the arrangement of the device as disclosed herein allows one to join metals by induction heating that would otherwise require considerably greater power supplies, that are not practical or indeed safe for most routine uses.

According to a second aspect of the invention, there is provided a process for joining two or more metal components together via a joint comprising: i) positioning said components in a device comprising a clamping member configured to releasably grip the said components, at least in the region of said joint, wherein said clamping member has at least one induction heat-conducting contact surface that is adapted to encase and mate with one or more of said metal components at least in the region of said joint; wherein the clamping member is operationally coupled to at least one urging member whereby force can be applied to the clamping member and transferred to the region of the joint for the purpose of forcing the said components there together; ii) activating said at least one induction coil positioned adjacent or about the clamping member, or a part thereof, which induction coil is connected to a power supply where, upon supply of power to said induction coil, said induction heat-conducting contact surface is heated; iii) allowing heating of said induction heat-conducting contact surface to join said components together via a joint; iv) before or after ii) or iii) applying a force to said clamping member, via said urging member for the purpose of forcing the said components there together; and v) removing the joined components from said device. In a preferred embodiment of the invention, said clamping member or at least its induction heat-conducting contact surface, is at least partially manufactured from a magnetically permeable metal or metal alloy. Preferably, said clamping member, or at least its induction heat-conducting contact surface, is at least partially manufactured from a material having a greater magnetic permeability than the magnetic permeability of, either one or both, the metal components to be joined. More preferably still, said clamping member is at least partially manufactured from a material having a magnetic permeability selected from the group comprising: 1 ,000-250,000, and every magnetic permeability integer therebetween. Yet more preferably still, said clamping member, or at least its induction heat-conducting contact surface, is at least partially manufactured from a material having a magnetic permeability of at least 5000, still more preferably at least 10,000, more preferably still at least 25,000, and more preferably still at least 50,000.

As mentioned, in order to provide rigidity during heating and also to apply uniform force across the region of the joint, the clamping member is operationally coupled to at least one urging member whereby force can be applied to the clamping member and transferred to the region of the joint for the purpose of forcing the said components there together. Most preferably, the clamping member is made of a material of sufficient hardness that when a force is applied to same, the clamping member transfers the applied force equally, across induction heat-conducting contact surface, thereby ensuring the formation of a strong and successful joint.

Ideally, the clamping member is manufactured from ferromagnetic or ferrimagnetic materials, more ideally materials selected from the group comprising: iron, nickel, cobalt, manganese, iron or steel, silicon, silicon carbide or alloys or mixtures thereof. Most ideally, the clamping member is silicone carbide, iron or an iron alloy. Additionally, as will be appreciated by the skilled person, the device of the invention has utility in joining together metal components that have relatively low magnetic permeability, such as but not limited to those materials with a magnetic permeability selected from the group comprising: 1 -500, and every relative permeability integer therebetween. Yet more preferably still, said metal components are manufactured from a material having a magnetic permeability less than 100, still more preferably less than least 50, more preferably still less than 10, and more preferably still less than 5, and most preferably about 1. Such materials include copper, aluminium, nickel, steel, gold, silver, or the like, and alloys thereof.

However, the skilled person will appreciate the components must be made from a material(s) that is/are thermally conductive.

In yet a further embodiment, said clamping member comprises an inlet, ideally in fluid communication with the at least one induction heat-conducting contact surface of same, and most ideally in the region of said joint, for delivery of one or more filler agents which when melted, during heating, assist in joint formation. Such agents include, but are not limited to, bonding agents, bonding powders, metal flux agents, solder or the like. Accordingly, in a preferred process according to this embodiment, said method further comprises, ideally prior to step ii), the additional step of delivering one or more filler agents as disclosed herein to the region of said joint via the inlet.

In yet a further preferred embodiment, said metal components comprise, in fact positioned therebetween, a filler or bonding agent or bonding powder which upon heating melts to facilitate joint formation and strong bonding. Examples of such filler or bonding agents include, but are not limited, silver, copper and phosphorous alloys such as Silfos foil.

In a further preferred method, said urging member is adapted to apply force to all parts of the clamping member or a substantial part of the clamping member. Ideally, this occurs prior to the commencement of step ii), and most ideally for the duration of step ii) and step iii) of the method. As will be appreciated, this is to ensure the metal components mate theretogether for the purpose of being joined.

In yet a further preferred embodiment, said method further comprises detecting the temperature of the clamp, preferably via a sensor in functional communication with the at least one induction heat-conducting contact surface of said clamping member, ideally the joint region thereof. As will be appreciated this can be at any time during the heating i.e. step ii) and/or iii) of the method. In this manner, the temperature of the joint region can be determined during the joining process and time allowed for the temperature to reach a level effective to achieve joint formation, but not too high that the metal excessively melts. Preferably, the temperature sensor is in operable communication with the induction coil, most ideally by way of a processor or sensing unit, whereby the processor/sensing unit can control activation/de- activation of the induction coil according to a signal, ideally an electrical signal, received from the temperature sensor. In this way an operator or a program can control the device. In a preferred embodiment, the processor/sensing unit can set a pre-determined temperature threshold, according to the nature of the metal to be joined.

According to a third aspect of the invention, there is provided a kit of parts comprising any one or more aspects of the device as disclosed herein, including a kit for joining two or more metal components together via a joint comprising: i) at least one clamping member configured to releasably grip the said components, at least in the region of said joint, wherein said clamping member has at least one removable induction heat- conducting contact surface that is adapted to encase and mate with one or more of said metal components at least in the region of said joint, wherein the clamping member is adapted to be operationally coupled to at least one urging member whereby force can be applied to the clamping member and transferred to the region of the joint for the purpose of forcing the said components there together; and ii) at least one induction coil positioned or adapted to be positioned adjacent or about the clamping member, or a part thereof, which induction coil is adapted to be connected to a power supply where, upon supply of power to said induction coil, said induction heat-conducting contact surface is heated.

In a preferred kit of the invention, said kit further comprises a power supply for powering the induction coil.

In yet a further preferred embodiment still, said kit further comprises one or more bonding agents, bonding powders, metal flux agents, fillers, solder or the like.

In a further preferred embodiment, said kit further comprises a temperature sensor for detecting the temperature of the clamp. More preferably, said temperature sensor is adapted to be in functional communication with the at least one induction heat-conducting contact surface of said clamping member, ideally the joint region thereof.

In a preferred kit of the invention, said at least one clamping member, and/or induction heat-conducting surface comprises at least one space, channel, indentation, recess, or the like, whose shape is complementary to at least a part of the joint between the metal components to be joined.

In a preferred kit of the invention, a plurality of removable induction heat- conducting contact surfaces and/or clamping members are provided, each one of which is adapted to mate with one or more different metal components at least in the region of said joint, whereby a number of different components can be joined theretogether using said device. As will be appreciated, in this manner a user can interchange the induction heat -conducting surface and/or clamping member according to the metal components to be joined and the join to be formed, for example, to achieve different metal joins as typically forming part of electrical earthing systems or plumbing systems or the like.

In yet a further preferred embodiment, the clamping member is operationally coupled to at least one urging member whereby force can be applied to the clamping member and transferred to the region of the joint for the purpose of forcing the said components theretogether.

Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of the words, for example “comprising” and “comprises”, mean “including but not limited to” and do not exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

All references, including any patent or patent application, cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. Further, no admission is made that any of the prior art constitutes part of the common general knowledge in the art.

Preferred features of each aspect of the invention may be as described in connection with any of the other aspects.

Other features of the present invention will become apparent from the following examples. Generally speaking, the invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including the accompanying claims and drawings). Thus, features, integers, characteristics, compounds or chemical moieties described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein, unless incompatible therewith. Moreover, unless stated otherwise, any feature disclosed herein may be replaced by an alternative feature serving the same or a similar purpose.

The Invention will now be described by way of example only with reference to the Examples below and to the following Figures wherein:

Figure 1. [A] A diagrammatic cross-sectional side view of a device according to a preferred embodiment of the invention. [B] A diagrammatic exploded isometric view of the clamping member according to a preferred embodiment of the invention. [C] A diagrammatic side perspective view of metal components joined using the device according to the invention.

Figure 2. A diagrammatic cross-sectional side view of the device showing in Figure 1A further comprising a urging member according to a preferred embodiment of the invention.

Figure 3. [A] Photographic side perspective image of a device according to a preferred embodiment of the invention. [B] Photographic image of a joined metal conductor plate, joined using the device according to the invention. [C] Joint strength test of the metal joined in [B], where significant weight (100kg) was hung from the joint and had zero impact on the joint, electrically or mechanically.

Figure 4. [A] A diagrammatic exploded isometric view of a clamping member according to a preferred embodiment of the invention. [B] A diagrammatic side cross-sectional view of the clamping member shown in [A] when assembled in a device according to a preferred embodiment of the invention. [C] A diagrammatic side cross-sectional view of a device according to the invention for use when clamping a cable lug. [D] A schematic of a joined cable lug using the device according to [C].

Figure 5. [A] A diagrammatic partial cross-sectional view of a device according to a preferred embodiment of the invention for use when joining larger railway track components. [B] A diagrammatic partial cross-sectional view of the device according to [A] when comprising the induction coil.

Figure 6. Photographic side perspective image of a device according to preferred embodiment of the invention joining electrical tape, in this arrangement in an end-on fashion.

Figure 7. Photographic side perspective image of a device according to preferred embodiment of the invention joining electrical tape, in this arrangement at 90 degrees with respect to one another to provide a right-angle joint. In this embodiment, as shown in [A] and [B], two different clamping members can be utilized where mating surfaces can encase end or middle portions of material to be joined.

Figure 8. Photographic side perspective image of a device according to preferred embodiment of the invention joining electrical tape, in this arrangement overlapping with respect to one another to provide a cross-join.

Referring now to the figures and, firstly, to figure 1A there is shown a perspective view of a typical device [1 ] of the invention for use to join two or more metal components [2] via a joint. In this particular example, a pair of rectangular planar rod conductors are shown, but the device can be used for other alternative metal components, such as metal components in earthing systems, plumbing components etc. where there is a need to achieve mechanical and electrical metal joints. In all examples, however, the device has particular utility in joining metal components that have relatively low magnetic permeability, or magnetism, that generally cannot be heated by induction without high levels of power.

Device [1 ] comprises a clamping member [3] which, in use, is configured to releasably grip the metal components [2] in the region of the joint to be formed. In the present example, the clamping member [3] is illustrated as two parts, or jaws [3a, 3b], which are used to encase or surround the metal components [2] at least in the region where the joint is to be made. In preferred arrangements, the first and second jaws [3a, 3b], may be hingedly attached to each other and/or adapted for relative movement. As will be appreciated, in this arrangement, the metal components [2] can be inserted into the clamp [3], and positioned between the jaws [3a, 3b], after which the jaws can be moved or closed to encase or surround the metal components [2] prior to the commencement of induction heating to form a secure joint.

In all embodiments, the clamping member [3] comprises at least one induction heat-conducting contact surface [3c] that is adapted to mate with the one or more metal components [2], This is illustrated in Figure 1 B. In this manner, the clamping member [3] is configured to accommodate or encase, in a mating manner, the metal components [2] to be joined. Typically, the clamping member is moulded to accommodate or encase, in a mating manner, the metal components [2], and may comprise at least one space, channel, indentation, recess, or the like [3c], whose shape is complementary to the joint between the metal components [2] to be joined. By providing such a space, channel, indentation, recess or the like, a precise and close mating joint can be made between the components that can withstand, when in use, an applied force across the entire joint. In the absence of this close mating the joint may subsequently fail. Advantageously, the geometry of the said space etc. is such that a tight complementary fit is provided between the clamping member [3] and the metal components [2], such that uniform force and heat can be applied.

As will be appreciated, the exact shape of the mating surface [3c] of the clamping member and in particular the space etc. therein, will be determined by the metal components [2] and their respective complementary shapes, including the shape of the joint to be formed, in order to encase, at the very least the joint, and usually parts of the two metal components to be joined tightly. Figure 1 B shows conducting contact surfaces [3c] having rectangular channels to accommodate rectangular conducting rods. However, alternative shapes of spaces, recesses etc. are also envisaged, of which examples are shown in figures 4 and 5. Figure 4 shows a partial cross-sectional view of a clamping member [3] having a first part whose contact surface [3c] is configured into a plurality of semi-circular channels, this part when used with its opposite part provide cylindrical channels, which have utility in joining cable lugs or copper pipework. Figure 5 shows a clamping member [3] having contact surfaces [3c] adapted to accommodate or mate with railway tracks which, when provided with the requisite power supply, can be joined using the device of the invention. As will be appreciated, the clamping member [3] is configured to accommodate the shape of the two metal components to be joined together. Thus, the configuration of the clamping member is bespoke and so manufactured for each particular joint to be made having regard to the metal components to be joined. In a preferred arrangement, the clamping member [3], or at least the induction heat-conducting contact surface [3c] thereof may be removable and/or interchangeable such that a user can utilise a different clamping member having a mating surface(s) adapted for use with the metal components to be joined, or the nature of the joint to be formed (Figure 1 shows a lap joint, but equally butt joints can also be formed using this technology).

As shown in Figure 1 , device [1 ] also comprises at least one induction coil [4], which is positioned adjacent or about the clamping member [3], In this illustration, a split coil is shown wherein each part, or jaw [3a, 3b], is adjacent an induction coil [4] and thus heated, however, a continuous coil surrounding the entire clamping member [3] is also envisaged, as shown in Figure 3a. The induction coil [4] may take any form known in the art, such as, but not limited to, a helical winding of hollow electrically conductive tubing, a solid rod, a flexible cable, and a machined billet. Additionally, although not shown, said induction coil [4], or at least a part thereof, ideally the exterior surface, is coated with a heat reflective material which ensures heat is not lost exteriorly from the clamp and thus heat is effectively redirected towards the internal side of the clamp or the contact surface(s) where the heat can heat the metal components thus reducing heat loss and so improving efficiency. Further, in preferred arrangements the induction coil [4] may further comprise a magnetic flux concentrator or coating to enhance the magnetic field and thus heating of the clamping member [3], As will be appreciated, particularly in embodiments wherein the induction coil [4] is positioned about only a part of the clamping member [3], such as only the first [3a] or the second jaw [3b], use of a flux concentrator permits one to extend the magnetic field to the other jaw thus achieving heating of the other jaw, albeit with reduced power. In order for the induction coil to produce the electromagnetic field and induce heating of the clamping member [3], an electrical supply in operatively connected to said induction coil [4] is required.

As disclosed herein, the joining of the metal components [2] is brought about by heat transfer, specifically by conduction, from the clamping member [3], which itself is heated via the induction coil [4], In particular, the clamping member [3], or at least its heat induction contact surface(s) [3c], is made of a material that can be readily heated by induction heating (i.e., having a high level of magnetism or being a magnetic metal, such as iron, or iron alloys, though other magnetically permeable metals are also applicable). Usually, the metal components to be joined have relatively low magnetic permeability, they are made of copper, aluminum, steel, nickel, gold, silver, or the like, including alloys thereof. This arrangement allows metals that otherwise cannot be heated by induction, unless considerable power is applied, to be easily heated. As will be appreciated, this is permissible because the metal components [2] are thermally conductive.

As will be appreciated, given that the metal components [2] are heated indirectly, in certain applications it may be desirable to monitor the temperature applied to the metal components [2], and so in certain arrangements as shown in Figure 1 the device [1 ], ideally the clamping member [3] which is heated, further comprises a temperature sensor [7] in functional communication with at least one of the heat-conducting contact surface [3c] of the clamping member [3], This allows the user to monitor the temperature of the joint region during the joining process and the time allowed for the temperature to reach a level effective to achieve joint formation, but not so high that the metal deleteriously melts. Although not illustrated, in certain arrangements the temperature sensor is in operable communication with the induction coil [4] or power supply, ideally via a processor, such that the supply of heat can be activated/deactivated according to a pre-defined temperature threshold.

To assist in joint formation, e.g., by improving the physical and/or electrical bonding, any means typically used in the welding/brazing industry can be used in combination with the device disclosed herein; such as the use of bonding agents, bonding powders, metal flux agents, solder or the like. As will be appreciated, such agents can be used in various manners, such as between metal components to aid joint formation, or surrounding/encasing the metal components to form a weld. As illustrated in figure 5, in some embodiments the device may comprise an inlet [8] to allow a user to add bonding agents to the joint during joint formation. However, other means to include such agents are equally envisaged as will be appreciated by the skilled person.

As best shown in exemplar Figures 2 and 4, it is important to ensure rigidity across the joint during heating and so the application of uniform pressure across the entire joint of the metal components [2], To ensure this is achieved, it is also preferable to apply a force to the clamping member [3], This, typically, is achieved using at least one urging member [5], such as vice or the like, functionally coupled to the clamping member [3] whereby force can be applied to the clamping member [3] and transferred to the region of the joint for the purpose of forcing the said components theretogether. The use of an urging member is also shown in Figure 6 where at least one urging member is in functional association with the clamping member in order to apply force to same to ensure the metal components mate theretogether for the purpose of a secure joint being formed. As illustrated in Figure 6, ideally the clamping member [3] has a surface [6] that is adapted to mate with the urging member, whereby a maximum external force can be applied. Ideally surface [6] and the co-operating contact surface of the urging member are substantially planar or flat. More ideally still the urging member is configured to apply a force to all parts of the clamping member or a substantial part of the clamping member. As shown in Figures 6-8, the use of different combinations of clamping members, with different channels or mating surfaces, allows one to achieve joints of differing shapes, orientations angles and geometries. Thus illustrating the flexibility of the technology for joining different metal components.

The invention therefore provides an alternative device and process for joining metal components theretoget that eliminates the need for the use of highly inflammable materials as in exothermic welding and conventional brazing techniques, thereby vastly improving safety. In addition, the lack of use of flammable gases leads to an eradication of waste gases, removal of acutely toxic materials, and so a reduced impact on the environment. Furthermore, our device and its use also reduce inter-user variability, allowing for greater consistency in joint formation and so the production of a consistently better product. Notably, as shown in Figure 3, the physical and electrical stability of these joins is superior. Further, as shown in Figures 6-8, through use of different combinations of clamping members, with different channels or mating surfaces, one can achieve joins of differing angles and geometries. Finally, by improving the physical and electrical connection properties of a joint, one can achieve a better and safer earthing system. In particular, the arrangement allows one to join, by induction, metal components that otherwise it would not be possible to join without excessive power supplies, thus paving the way for improved usability in the field in the form of portable, and safe, joining devices and processes.