JP2011500332A - Hose assembly - Google Patents

Abstract

The present invention has a plurality of current conducting leads (25, 44), wherein the leads (25, 44) include an aluminum wire, and the current conducting leads (25, 44) are accommodated in a channel. And a hose assembly (1) for arc welding or cutting torch having channels (5, 22) for guiding welding wires (6, 21).
[Selection] Figure 1

Description

  The present invention relates to a hose assembly for an arc welding or cutting torch having a plurality of current conducting leads, the leads including aluminum wires, the current conducting leads being received in the channel, and having a channel for guiding a welding wire. About Lee.

  Arc welding and cutting torches have long been known in the prior art. This type of welding and cutting torch can be implemented for manual and automatic welding. Most manual arc welding and cutting torches include a base and a handpiece, which are interconnected via a hose assembly. In manual arc welding and cutting torches, it is essential that the handpiece be movable as freely as possible. Therefore, the material for it must have a particularly excellent reverse fatigue strength under bending and torsional stress.

  Arc welding and cutting torches for automatic welding are often configured as a robot that includes a movable robot arm that rises to the area to be welded. In such a case, the hose assembly is provided between the base and the actuator. In automatic welding, the robot arm often operates at high acceleration, which increases the welding speed. The hose swings freely within certain limits and is therefore exposed to high mechanical stresses.

  Welding requires a high level of power that must be transported from the base to the handpiece via a power cable. In the prior art, only copper is used in power cables for arc welding and cutting torches because of their high conductivity. Another property of copper is its high thermal conductivity, which allows the heat generated as a result of resistance to be carried away quickly. Copper also meets the necessary requirements for mechanical properties. In the prior art, the power cable is typically configured as a stranded wire.

  It is also known in the art that electrical conductors can be made from any type of metal.

  A hose assembly having the characteristic properties described at the beginning is also known from DE 1515145A. To guide the welding wire, the welding cable includes a sheath made of a flexible synthetic material having a completely smooth inner wall. The sheath is surrounded by a spiral winding of copper or aluminum wire for conducting current. The wire bundle is encapsulated on the outside by a single layer of rubber. In order to strengthen the cable against tensile stress, the conductor can be encapsulated in a steel braid.

  German Utility Model No. 8509258 U1 discloses a welding cable in which a portion of the current conducting lead is made from aluminum and another portion of the current conducting lead is made from copper. In this case, the inner conductor is made of aluminum and the outer conductor is made of copper wound on the inner conductor.

  The copper conductors currently used in hose assemblies have the disadvantage that they account for 2/3 of the total weight of the hose assembly, so that handling of the hose assembly over a long period of time can lead to fatigue. The stress on the hose assembly used for automatic welding also increases with the inertial mass of the hose assembly.

  German Patent No. 2052462B2, German Patent No. 2112452A, US 2006 / 0102368A1, US Pat. No. 6,178,623 B1, and US Pat. No. 3,926,573 have an aluminum core on which a copper layer is directly or A conductor is described which is applied indirectly as an outer sheath.

  German utility model No. 8509258U1 is composed of two kinds of conductor materials such as aluminum and copper, and a single conductor with high conductivity value, density and breaking load like copper is low like aluminum It relates to a welded cable that is twisted onto a conductor having a conductivity value, density, and breaking load.

  German Patent No. 2409322 A1 is a tube made from a rubbery flexible and optionally refractory material configured to accommodate separate elements and leads commonly used in inert gas welding techniques. A tubular piece having a plurality of separate channels is disclosed.

  EP 0076390 A1 also describes an apparatus for inert gas welding using fusible wire electrodes. In this case, a coaxial hose assembly is provided that includes a welding current lead, a control lead, and an annular gap for conducting an inert gas. The wire electrode is placed in the center of the hose assembly inside a gas impermeable flexible sheath.

  German Patent No. 880636U1 provides a torch for inert gas arc welding to a hose assembly comprising a power cable, an inert gas line, a cooling water intake line, a cooling water return line, and a switch cable. The end of the hose assembly facing the torch is connected to the current / water cable for the torch and the power cable and the fitting for the cooling water intake line and the assigned lead for the torch. An apparatus is disclosed that opens into a housing that houses fittings for active gas lines and other cooling water lines, and that fittings for switch cables are also housed in the housing.

  DIN EN 60228 (September 2005), for conductors for cables and insulated leads, defines the nominal cross-sections of cable conductors and insulated conductors for power systems. It also includes wire number and dimensional requirements and resistance value requirements. Conductors include single and multi-wire conductors made from copper, aluminum, and aluminum alloys for permanent installation, and flexible copper conductors.

  The object of the present invention is for arc welding and cutting torches which are substantially lighter than hose assemblies comprising copper cables known in the prior art, but which have relatively advantageous mechanical properties, especially with respect to torsional or bending stresses. To propose a hose assembly.

  This object is achieved by a hose assembly according to claim 1. Advantageous embodiments are described in the dependent claims.

  The use of a copper clad aluminum wire as a current conducting lead in a hose assembly has the advantage of reducing the weight of the assembly while at the same time eliminating the occurrence of high temperatures at the transition point between conductors and connections. This is probably due to the fact that using copper on the aluminum wire substantially reduces the essentially high transition resistance between the aluminum and the respective connection, thus using conventional copper conductors. Compared to cases, weight reduction is achieved, but the electrical and mechanical properties of the conductor are largely maintained. In this case, the plurality of current conducting leads are coaxially arranged around the central channel. This allows the functions performed by the hose assembly to be combined with a smaller number of individually independent hoses. This also makes it possible to achieve a synergistic effect, for example when conveying the cooling medium using a central channel. In that case, the current conducting leads that generate heat can simultaneously be actively cooled by the cooling medium. A channel for guiding the welding wire is also provided. This allows a relatively large amount of welding wire to be stored in the base station of the welding unit and guided through the hose assembly to the handpiece as needed. A channel for current conducting leads is also provided. Especially in coaxial assemblies, it may be necessary to spatially separate the individual functions performed by the hose, for example because the potential of the current conducting leads is different from the potential of the welding wire transported in the hose assembly. possible. Furthermore, all channels are arranged coaxially. This allows for the most efficient use of existing space, creating a smaller diameter hose assembly and consequently easier handling. The channel containing the current conducting lead surrounds the channel for conducting the media, and the channel for conducting the media surrounds the channel for guiding the welding wire. Thus, the media channel can be used to simultaneously cool the welding wire channel and the channel containing the current conducting leads.

  Needless to say, in one preferred embodiment of the present invention, all current conducting leads of each current conductor are embodied as a copper clad aluminum wire. In this case, the individual conductors can be embodied in the form of individual wires, stranded wires or the like.

  It has also been found that the use of copper clad aluminum wire in the hose assembly of the present invention is much more cost effective. This is because the machining is substantially simplified by the simplified wire drawing process.

  The connector of the hose assembly can be connected to one or more current conducting leads via a crimp connection.

  However, one preferred variation requires that the current conducting leads of the copper clad aluminum wire be connected to the hose assembly connector by ultrasonic welding. In that case, the outer strand of the current conducting lead of the hose assembly can be closed directly with a copper sleeve. This connection method has the advantage that the transition resistance is low and therefore the temperature rise at the transition point is also low. This ultrasonic welding process can be used for both aluminum wires and aluminum wires having a single copper layer on their outer sheath. It has also been found that the ultrasonic welding process significantly increases the strength of the connection or sleeve over the strength of the crimp connection. Both copper and steel sleeves can be used as connectors.

  The copper coating on the aluminum wire is advantageously 1-100 μm thick. This dimension ensures optimization of the copper clad aluminum wire in the sense of minimizing its weight with the lowest possible transition resistance.

  Also, in the hose assembly, the current conducting leads configured as stranded wires in which the individual strands of the stranded wires include aluminum meet the requirements for use in arc welding and cutting torches.

  The hose assembly according to the present invention has the advantage that it is substantially lighter than the copper lead hose assembly and is therefore easier to handle. Despite the increased amount of aluminum required for conduction, the total weight of hose assemblies made with aluminum strands is substantially lower than the total weight of conventional hose assemblies.

  The hose assembly of the present invention has a longstanding experience that those skilled in the art have had that aluminum cables should not be used in hose assemblies due to the unfavorable conductive properties of aluminum cables and due to their bending and breakage. Overcoming preconceptions.

  By configuring the aluminum lead as a stranded wire in which the individual strands are relatively thin, the bending and torsional stress acting on the individual strands is lower than that of the strands having a larger cross-sectional area.

  For individual strands, pure aluminum having a purity of A199 to A199.9 has proven to be particularly well suited. However, an aluminum alloy may be used.

  It is advantageous to provide at least one composite lead that includes individual strands made from copper-coated aluminum or an aluminum-containing alloy and individual strands made from copper or a copper-containing alloy. Surprisingly, it has been found that this type of composite lead substantially improves the removal of heat from the lead and the total cost of the hose assembly is much more advantageous than pure copper leads.

  The lead advantageously has at least four individually stranded wires arranged around the core strand. A lead having this type of structure is very flexible even if the lead cross-sectional area is large.

  Each individual strand and / or core strand is advantageously made from 20 individual strands. This further increases its flexibility and reduces the risk of cable breaks.

  In one advantageous embodiment of the invention, the individual strands have a diameter of 0.05 mm to 0.5 mm. A diameter of 0.15 mm is particularly preferred. The diameters of the individual strands such as these make it possible to achieve the necessary conduction parameters.

  It is particularly advantageous to wind current conducting leads, in particular current conducting strands, spirally or spirally around the central channel. In the hose assembly, the current conducting leads or strands extend in a spiral or spiral around the center channel, preferably outside, so that when the hose assembly is bent, stretched, compressed or twisted The bending stress acting on the current conducting lead is dispersed. In particular, twisting the lead or strand around the central channel releases the stress on the hose assembly in the range of the minimum radius of curvature of the current conducting lead or strand.

  The twist length of the stranded wire is advantageously 15 mm to 200 mm, particularly preferably 40 mm to 60 mm. Such twisting improves the mechanical properties of the hose assembly.

  It is advantageous to provide at least one additional control current lead. This makes it possible to easily control the function of the welding apparatus using the handpiece.

  It is particularly advantageous to provide at least two channels for conducting the medium together with at least two current conducting leads. Similar to the case described above, the combination of the media conduction lead and the current conduction lead produces a positive effect on the efficiency of the current conduction. By providing at least two channels with a current conducting lead where the current conducting lead is centered so that the media can flow directly around it, the surface of the lead and hence the amount of heat that the lead releases Will increase. Furthermore, the cross-sectional area of the lead can be increased while maintaining the flexibility of the lead. This can increase the total power that can be conducted through the hose assembly.

  The polymer has proven to be a suitable medium for the channel. Polymers can meet the requirements of the maximum width range and have proven effective for long-term use.

  The medium is preferably composed of a gas or a liquid. The medium can be a process gas, such as an inert gas used in inert gas welding, or a liquid, for example to cool the handpiece.

  The current conducting lead advantageously has a connector at one end which is connected to the current conducting lead via a crimp connection. Surprisingly, it has been found that this type of crimp connection forms a reliable and reliable connection between the current conducting leads and the connector over time.

  Alternatively or additionally, the current conducting leads can be welded to the connector or strand end sleeve via ultrasound. It has been found that copper-clad aluminum wire can be reliably connected to the connector not only via a crimp connection but also via ultrasonic welding. In the case of the latter (ultrasonic welding), a quasi-similar substance that can be joined better as a result is obtained on the connection surface.

  Additional goals, advantages, characteristic features, and potential applications of the present invention are included in the following description of several exemplary embodiments associated with the set of drawings. All features described and / or illustrated are subject matter of the present invention, either alone or in any logical combination, regardless of how they are combined within the claims or references to previous claims. Configure.

It is sectional drawing of the hose assembly which concerns on this invention. FIG. 6 is a cross-sectional view of an alternative embodiment of a hose assembly according to the present invention. 1 is an embodiment of a so-called current / water cable according to the present invention. 1 is a longitudinal sectional view of a current cable according to the present invention. FIG. 5 is a cross-sectional view of the cable of FIG. 4 along line AA. It is a perspective view of a stranded wire.

  FIG. 1 is a schematic illustration of a hose assembly 1 according to the present invention, such as used in arc welding or cutting torches. In the exemplary embodiment selected here, the hose assembly 1 combines several individual hoses together inside the outer hose 2, and the individual hoses from the base (not shown) of the welding apparatus. Guide to the handpiece (also not shown here) or from the base of the automatic welder to the actuator.

  The hose assembly 1 has a cooling medium suction hose 3 in which the cooling medium is conveyed from the base to the handpiece or actuator. A process gas hose 4 is also provided, and the process gas flows inside to form an inert gas atmosphere. A wire guide hose 5 is also provided, which transports the welding wire 6 inside a spiral wire guide 7 provided in the wire guide hose 5. A control lead 8 is also provided, through which control signals are transmitted from the handpiece or actuator to the base.

  A so-called current / water cable 9 is also provided. A current conducting lead 11 is provided inside the hose 10 of the current / water cable 9 and will be described in more detail below. Between the hose 10 and the current conducting lead 11, a channel 12 for cooling medium return is provided. This provides the advantage that the cooling medium in the cooling medium return can also cool the current conducting leads 11 that become very hot due to the high power required for welding.

  Additional leads can be provided inside the hose assembly 1.

  FIG. 2 shows an additional embodiment of a hose assembly 20 according to the present invention. The hose assembly 20 shown in FIG. 2 has an essentially coaxial arrangement of individual elements. Inside the hose assembly 20, the welding wire 21 is guided inside the spiral wire guide 22. An intermediate space 23 is provided surrounding the spiral wire guide 22 and serves to carry the process gas. The hose 24 is provided to form an airtight seal. The hose 24 is made of elastic plastic. A current conducting lead 25 and a control lead 26 shown here in black are arranged on the hose 24. The current conducting lead 25 has a twisted wire configuration according to the present invention, which is defined in more detail in connection with FIG. The hose assembly 20 is held together by an outer hose 27 that surrounds all the hoses. An annular channel is formed between the outer hose 27 and the hose 24 to hold the current conducting lead 25 and other leads. The hose assembly 20 may be part of a larger hose assembly in which additional hoses of various purposes are provided, such as a cooling medium hose. Current conducting leads 25 and 44 (FIG. 5) are spirally wound around the central channel 23 or 41 (FIG. 5). Thus, the current conducting leads and stranded wires 25, 44 are each located in the outer region of the cross section of the hose assembly. This measure makes it possible to distribute and thus reduce the bending stress on the current conducting leads 25, 44, especially in the region of the minimum radius of curvature of the hose assembly.

  FIG. 3 shows an enlarged view of the current / water cable 9 of FIG.

  The current / water cable 9 includes an outer hose 30 which is embodied in a watertight manner and allows a cooling medium to be carried. Instead of water, any other fluid known in the prior art can be used as the cooling medium. In the coaxial arrangement, the current conducting lead 11 is arranged at the center of the current / water cable 9.

  The current conducting lead 11 is embodied as a stranded wire composed of individual strands 32. The individual strands 32 of the stranded wire 11 are made from aluminum or an aluminum alloy. Pure aluminum having a purity of A199 to A199.9 has proven particularly suitable for this purpose. These strands 32 are encapsulated or covered by a single copper layer, thereby substantially reducing the transition resistance. The thickness of the coating is between 1 and 100 μm.

Each individual strand 32 has a strand diameter of 0.1 to 0.3 mm. About 30 individual strands have been bundled into a single strand, and strands containing up to 100 individual strands have proven appropriate in terms of their elastic properties. While the cross-sectional area of such a stranded wire is approximately 10 mm ^2, known copper twisted wire from the prior art having a cross-sectional area of, for example 6 mm ^2. With aluminum, cross-sectional areas up to about 30 mm ² are readily possible. The twist length of the stranded wire itself is about 60 mm, but can be in the range of 15 mm to 200 mm depending on the cross-sectional area of the stranded wire.

  In the case of so-called composite leads, copper-coated individual wires made from aluminum or aluminum alloys and individual wires made from copper or copper alloys can also be used for the stranded wires.

  In a further embodiment not shown here, the current conducting lead 11 can have a plurality of stranded wires, in which a core wire is provided, around which an outer stranded wire 31 is arranged.

  A single hose assembly can be provided with multiple current / water cables as shown in FIG. Two current / water cables have proven particularly preferred, one used to supply the cooling medium and one used to return the cooling medium. In this way, it is possible to improve the cooling power of the cooling medium on the current conducting leads while splitting the current conducting leads, thereby increasing the flexibility of the hose assembly. This type of assembly is known in the prior art.

  FIG. 4 shows a longitudinal sectional view of a power cable 40 having a connection 35 to the base of the welding apparatus. The connecting portion 35 includes a hexagon nut 36 for connecting the power cable 40 to the base in a properly aligned state. A line end sleeve 37 and a ferrule 38 that house the end of the lead 40 are also provided.

  Also shown is a control lead 43 that is connected to the base via a separate plug connector 39. The control lead 43 extends out from the outer sheath 46 of the power cable 40 in front of the end region of the power cable 40. Inside the hose 40, the crimp connection forms a hollow region 41 that extends from the connection 35 to the opposite end of the lead 40, which is tightly sealed. Region 41 may be air tight and / or fluid tight.

  FIG. 5 shows a cross-sectional view of the power cable along section line AA of FIG. Inside it is a region 41 that can be used to conduct either the cooling medium or the process gas.

  The inner region 41 is sealed by a hose 42. A plurality of leads having various functions are arranged outside the hose 42. The control lead 43 for controlling the function of the welding apparatus is indicated by a dense oblique line. The current conducting leads 44, which are also embodied as stranded wires, are indicated by sparse diagonal lines. The area 45 is not assigned a specific function. Region 45 can be filled with a filler or, for example, a plastic cord. Leads 43, 44 and area 45 are surrounded by hose 46.

  FIG. 6 shows a perspective view of the current conducting lead 11 of FIGS. Individual strands 32 are wound around the core wire 47. A half twist is shown here. The length of the twist d, that is, the length in the conduction direction in which the individual wires 32 are completely wound around the core lead 47 is 60 mm. However, the length of the twist can be changed from 20 mm to 120 mm depending on the thickness of the lead 11 and the thickness of each individual strand 32. Leads embodied in this way have the advantage of being able to withstand many types of stress. The lead 11 can be twisted in both directions, bent and stretched, or compressed. Furthermore, the elasticity of the lead embodied in this way is significantly greater than that of a lead made from a solid material having the same lead cross section.

DESCRIPTION OF SYMBOLS 1 ... Hose assembly, 2 ... Outer hose, 3 ... Coolant suction hose, 4 ... Process gas hose, 5 ... Spiral wire guide, 6 ... Welding wire, 7 ... Spiral wire guide, 8 ... Control lead, 9 ... Current / Water cable, 10 ... hose, 11 ... current conducting lead, 12 ... channel, 20 ... hose assembly, 21 ... welding wire, 22 ... spiral wire guide, 23 ... channel, 24 ... hose, 25 ... stranded wire, 26 ... control lead, 27 ... outer hose, 30 ... outer hose, 32 ... individual wire, 35 ... connection part, 36 ... hexagon nut, 37 ... wire end sleeve, 38 ... ferrule, 39 ... plug connector, 40 ... power supply Cable, 41 ... area, 42 ... hose, 43 ... control lead, 44 ... current conduction lead, 45 ... area, 46 ... hose, 47 ... core wire, d ... twisted strand.

Claims (16)

A hose assembly (1) for arc welding or cutting torch, having a plurality of current conducting leads (25, 44) comprising aluminum wires, said current conducting leads (25, 44) being received in a channel. In the hose assembly (1) having channels (5, 22) for guiding the welding wires (6, 21),
The current conducting leads (25, 44) are arranged coaxially around a central channel (23, 41) for conducting the medium, the channels are all arranged coaxially, and the channels of the current conducting leads (25, 44) Surrounding channel (23, 41) for conducting the medium, enclosing channel (22) for guiding the welding wire (6, 21). The hose assembly wherein the leads (25, 44) comprise an outer sheath made from a single copper layer.   The hose assembly according to claim 1, wherein the copper layer has a thickness of 1 to 100 μm.   One lead (25, 44) has at least one stranded wire (11, 25, 44), and each individual strand (32) of the stranded wire is made of a copper-coated aluminum wire. Hose assembly according to claim 1 or 2, characterized in that   4. A hose assembly according to any one of claims 1 to 3, wherein the aluminum wire is made from aluminum or an aluminum alloy.   At least one composite lead (11, 25, 44) comprising individual wires (32) made from copper-coated aluminum or an aluminum-containing alloy and individual wires made from copper or a copper-containing alloy The hose assembly according to any one of claims 1 to 4, wherein a hose assembly is provided.   6. The current conducting lead (11, 25, 44) according to any one of the preceding claims, characterized in that it has at least four individual stranded wires arranged around a core stranded wire. The hose assembly as described.   Hose according to claim 6, characterized in that each individual strand (11, 25, 44) and / or each core strand consists of at least 20 individual strands (32). Assembly.   Hose assembly according to any one of the preceding claims, characterized in that the individual strands (32) have a diameter of 0.05 mm to 0.5 mm, preferably 0.15 mm.   9. The current conducting lead (25, 44), in particular the current conducting strand, is arranged in a spiral or spiral around the central channel (22, 41). The hose assembly according to claim 1.   10. The length of the twist (d) of the stranded wire (11, 25, 44) is in the range of 15 mm to 200 mm, preferably in the range of 40 mm to 60 mm. The hose assembly as described in.   Hose assembly according to any one of the preceding claims, characterized in that at least one additional control lead (8, 43) is provided.   12. The method according to claim 1, wherein at least two channels (3, 4, 12) are provided for conducting the medium, and at least two current conducting leads (25, 44) are provided. The hose assembly according to item.   Hose assembly according to any one of the preceding claims, characterized in that the channels (12, 23) are separated from one another by a polymer.   14. The hose assembly according to any one of claims 1 to 13, wherein the medium is a gas or a fluid.   The current conducting lead (9, 20, 25, 40, 44) has a connection (35) at one end which is connected to the current conducting lead (9, 20, 25, 40, 44) via a crimp connection. The hose assembly according to claim 1, wherein the hose assembly is connected.   16. The current-carrying lead (9, 20, 25, 44) is ultrasonically welded to the connection (35) or the wire end sleeve (37). The hose assembly as described.

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