DE102022100148B4 - Resistance welding device in an electromagnetically optimized arrangement and corresponding resistance welding process and use - Google Patents

Abstract

The present invention relates to a resistance welding device optimized with regard to (electro)magnetic fields in an electromagnetically optimized arrangement and a corresponding resistance welding method, in particular a resistance welding device (10) having: electromagnetic components (12) coupled/coupable to an energy unit (11) set up to provide the Welding energy required for resistance welding, in particular at least comprising the following components: transformer (group); welding electrodes; a compressive force unit (15) set up to provide the compressive force required for resistance welding on the joining partners to be welded; a control/regulation unit (20) set up to control/regulate the resistance welding process; wherein the resistance welding device (10) in plan view has at least three arms (19) or columns in a star-shaped arrangement with at least threefold redundancy of the electromagnetic components (12) around a centrally arranged welding processing point (M). In particular, this also provides advantageous (electro)magnetic conditions in the area of the joint in the central welding processing point.

Description

TECHNICAL AREA

The present invention relates to a resistance welding device, in particular a KE resistance welding device, comprising: electromagnetic components which are/can be coupled to an energy unit for providing the welding energy; welding electrodes; a compressive force unit for providing a compressive force on the joining partners to be welded; and a control/regulation unit configured to control/regulate the resistance welding process; the individual relevant system components being arranged relative to one another in an electromagnetically optimized arrangement. Furthermore, the present invention relates to a corresponding resistance welding method and the use of an electrical/electronic interconnection of first, second and third electromagnetic components to provide the (welding) energy required for resistance welding and to provide at least triple redundancy of these electromagnetic components in a relative spatial arrangement to one another to compensate or level out electromagnetic influences. In particular, the invention relates to a device according to the preamble of the independent claim.

BACKGROUND OF THE INVENTION

Electromagnetic fields (EM fields) are generated during resistance welding, especially KE welding. However, these EM fields can have a negative effect on the quality of the welded connection, especially from a certain thickness/width or from a certain diameter of the welded joint to be created or from a certain size of the joining partners to be bonded or from a certain current intensity. Resistance welding, in particular capacitor discharge (KE) welding, requires a (very) high current intensity, for example in the range from 100 to 2,500 kiloamperes [kA], at least briefly during the discharge, which lasts for example only 50 ms. The welding energy is, for example, 10 to 300 kilojoules [kJ].

According to the prior art, resistance welding, in particular capacitor discharge (KE) welding, is carried out in many applications using systems which have one transformer or two (groups) of transformers. With only one transformer (or only one transformer group), a C-frame arrangement is implemented for many applications. In the case of two (groups) of transformers, these are arranged, for example, to the side of the joining partners opposite one another. Based on this, there is interest in a system that is further improved with regard to electromagnetic fields or electromagnetic influences on the welded joint.

The publication can serve as an example DE 201 13 032 Ul are called, which describes a resistance welding system with a double C frame. Furthermore, the following publications can be mentioned, each of which has a plurality of arms with electromagnetic components: DE 21 00 742 A , DE 382 902 A , DE 28 43 531 A1 .

Based on the state of the art, there is therefore a need for resistance welding systems and corresponding processes that are further optimized in terms of the quality of the weld joints that can be achieved, in particular for CD welds, in particular for the materially bonded connection of comparatively large workpieces/joining partners, in particular in the case of material-intensive weld joints or for workpieces or weld joints with a comparatively large diameter.

SUMMARY OF THE INVENTION

The object is to provide a resistance welding system or a resistance welding method, with which resistance welding can be carried out with high quality and with minimized (electro)magnetic negative effects. It is also an object to design a resistance welding system or a resistance welding process in such a way that the system or the process can also deliver the material-to-material welded connection with very good quality even for particularly thick or large or material-intensive welds or welded joints, in particular with a comparatively large diameter of an annular joint. Last but not least, the task is to design resistance welding systems or resistance welding processes in such a way that automation and, preferably, a short cycle time (or high output, large number of items per time unit) can be implemented with a good cost-benefit ratio.

This object is achieved by a resistance welding device according to claim 1, by a method according to the independent method claim and by a use according to the independent use claim. Advantageous developments of the invention are explained in the respective dependent claims. The features of the exemplary embodiments described below can be combined with one another unless this is explicitly denied.

A resistance welding device is provided, in particular a KE resistance welding device, comprising: electromagnetic components which are/can be coupled to an energy unit and are set up to provide the welding energy required for resistance welding, in particular at least comprising the following components: transformer (group); welding electrodes; a compressive force unit set up to provide the compressive force required for resistance welding on the joining partners to be welded; and a control/regulation unit configured to control/regulate the resistance welding process; According to the invention, it is proposed that the resistance welding device has at least three arms (according to the top view, or at least three columns in the side view) in a star-shaped arrangement with at least threefold redundancy of the electromagnetic components around a centrally arranged welding processing point. Among other things, this also enables electromagnetic effects to be leveled out or welding in a welding processing point to be largely free of electromagnetic interference. In this way, a comparatively homogeneous (or more homogeneous) magnetic field can be realized. In particular, the advantageous effect can be ensured that the current distribution in the components or workpieces/joining partners involved is comparatively homogeneous/undisturbed or can become more homogeneous than in previous systems. In particular, the advantageous effect can also be ensured that the weld seam is heated comparatively homogeneously or more homogeneously and the joining partners are welded comparatively uniformly or more uniformly than before (are joined with a material bond). It can also be ensured that there is no displacement of melt (or melt drops) along the weld seam (or at least significantly less than in previous systems or with previous methods). In this respect, according to the invention, advantageous increases in quality can be achieved and the reproducibility of the weld can be improved, especially with comparatively large workpieces/joining partners and (especially in diameter) large weld joints or generally with material-intensive weld joints, especially also in connection with automated production of large quantities with the minimum/shortest possible cycle time. Last but not least, this also expands the application possibilities of KE welding processes.

In this case, the electromagnetic components are arranged in a spatial arrangement relative to one another in order to compensate for electromagnetic influences with regard to the centrally arranged welding processing point.

For example, in the case of workpieces/joining partners with a joining diameter in the range of 100-200 mm or even in the range of 200-300 mm, the advantageous inventive effects described here are particularly noticeable.

It has been shown that the star-shaped arrangement of in particular three redundant electromagnetic assemblies (in particular including the transformers or transformer groups) around a/the central welding processing point provides very advantageous effects in terms of minimized interference fields in the welding processing point, especially in the case of material-intensive welded joints/welds. In other words, negative electromagnetic effects on the weld, particularly during discharging, can be largely avoided thanks to the relative arrangement of the electromagnetic components, particularly in the area of the joining plane. It has also been shown that the measures according to the invention are already particularly noticeable based on a cluster-like redundant arrangement of at least the (groups) of transformers.

The present invention is also based on the finding that the at least triple redundancy of the EM components is of great importance or of great benefit in terms of scalability of the system and method. In particular, since the disadvantageous effects described here could only be seen with comparatively large or material-intensive welded joints and could be linked to the previous system design and the way the energy was provided, it was not evident to even consider the additional effort associated with the triple redundancy of the EM components; Rather, only a systematic comparison of several welds (especially size comparison) and process and plant concepts could lead to the findings according to the invention.

"Electromagnetic components" are to be understood in particular as the transformers, in a broader sense also all electromagnetically active components or all current-carrying components or components that can be controlled in connection with the welding, which generate an electromagnetic effect or an electromagnetic field, in particular those components that interact with the transformers in terms of energy or current-carrying or can at least be arranged in the immediate local vicinity. From electromagnetic comp A distinction must be made here between power electronic components, which are usually arranged separately in a control cabinet and can therefore be arranged separately from the welding processing point anyway. In this respect, it can also be worked out as a feature of the system concept according to the invention that all electronic power components can be arranged in a separate switch cabinet outside the device-technical system boundary (housing, enveloping surface) defined by the system.

In a narrower sense, “providing the energy required for resistance welding” can be understood as providing the discharge energy, i.e. the flow of energy that is related to the functioning and charging of the capacitors. "Providing the energy required for resistance welding" can also be understood here in a broader sense as an installation or the corresponding process steps provided for the energy flow in a section between an energy supply and the welding processing point that is to be defined in particular in an application-specific manner.

In particular, a welding processing area is also to be understood as a welding processing point; this area can have an extent depending on the weld to be made or on the joining partners to be joined, for example 200 to 500 mm; In this respect, the wording "point" is not to be understood in a strictly geometric sense, but in particular as a designation for the central or concentric arrangement of the welding/processing area provided for the joining partners. For example, the radial extension of the welding processing point/welding processing area is at most 15 to 20% of the absolute radial extension of a single arm.

The arm here is the corresponding system section for arranging and accommodating the redundant electromagnetic components; the term "arm" was chosen in view of the star-shaped arrangement of the redundant electromagnetic components around the central processing point; if you look at the system from the side, you can also speak of a column instead of an arm; in this respect, these terms can be understood synonymously here; the term "column" can also describe an extension of the EM components (in particular with regard to a vertical extension of a tripod portal or a cross arrangement with fourfold redundancy), and the term "arm" can also describe an alignment optionally extending in a star shape from the central point (especially in the case of a portal-like design); also in this respect the present invention can be described by both terms.

The energy unit provides energetically effective components in an arrangement between an energy supply or an energy/electricity network and the transformers or other EM components of the resistance welding device. Depending on the existing infrastructure and depending on the configuration of the resistance welding device, the EM components can be (permanently) connected to the energy unit or coupled to the energy unit for the respective application. The energy unit is described here as a single energy unit; depending on the site-specific infrastructure or depending on the system configuration, however, a breakdown into several energy units can also prove to be advantageous; Since the system according to the invention is preferably designed for a (single) central welding processing point, since control/regulation aspects are also about a single (currently taking place) weld, it seems appropriate here to speak of only a single energy unit (and analogously of only a single control/regulation unit). With a production line, however, the respective number can be scaled. The energy unit is preferably coupled to a control cabinet.

The welding electrodes can, for example, be installed in the compressive force unit (at least one of them) and are preferably arranged centrally, in particular in the central welding processing point or along a vertical axis running through it.

For example, the arms with the redundant EM components extend like a portal at three points to the side of the joint, in particular with a common roof-like spanning area, in particular with exactly the same angular offset (in the joint plane or around the vertical axis). In this respect, one can also speak of a tripod portal formed by the three transformers (groups) ("tripod" in particular in the sense of three columns or three eccentric clusters).

It has been shown that the arrangement of the EM components according to the invention allows comparatively large degrees of freedom, in particular with regard to transverse distance, height (height position and extension in the height direction) and connection to the other system components, so that a respective system/device also remains application-specifically individualizable.

Personified terms, insofar as they are not formulated in the neuter (eg "skilled worker"), can refer to all genders in the context of the present disclosure.

According to one embodiment, the resistance welding device forms a star-shaped portal around the central welding processing point (or above the welding processing point), with the individual arms or columns of the star-shaped portal (arranged radially outwards from the central welding processing point) each receiving at least the following electromagnetic component: transformer (group). Last but not least, this promotes an electromagnetically advantageous superimposition of fields. The star-shaped arrangement can optionally be formed by an odd or even number of redundant EM components (in particular transformers (groups)), i.e. a cross arrangement of four redundant EM components offset by at least approximately 90° relative to one another can also be implemented using the concept according to the invention. In particular, the redundancy of the EM components can be a four-fold redundancy, in which the EM components form two portals arranged at 90° relative to one another. In this respect, the resistance welding device can also form a star-shaped portal with either three or fourfold redundancy of the electromagnetic components around the central welding processing point.

Optionally, the individual arms or pillars of the star-shaped portal can also accommodate other EM components in addition to the (groups) of transformers. In particular, the person skilled in the art can define application-specifically to what extent further clustering by further possibly EM-relevant components on the individual arms or columns is advantageous; the respective specific design can also depend on the type of energy supply or on other parameters such as those of the welding process.

According to one embodiment, the resistance welding device forms a star-shaped tripod portal around the central welding processing point, in which the individual arms or columns are arranged at an angle of at least approximately 120° to one another in a plan view, i.e. with an at least approximately rotationally symmetrical arrangement around the central welding processing point. Last but not least, this favors a leveling out or at least a strong reduction of electromagnetic interference, particularly in the central processing point. In this case, with this (only) triple redundancy, a very advantageous ratio of additional outlay in terms of installation technology and advantageous (electro)magnetic effects is also particularly useful.

According to one embodiment, the resistance welding device has a window between at least two of the arms or columns of the star-shaped arrangement for access for a processing robot or human to the central welding processing point, in particular at least three windows for access between all arms adjacent to one another or between each two of the arms or columns. Last but not least, the system configuration according to the invention also favors process automation in/on a production chain in which welding is only one of many steps; for example, the system can be loaded from three sides or remain accessible for processing by humans/robots and/or for the removal of semi-finished products or intermediate/end products.

According to one exemplary embodiment, the redundant electromagnetic components are each arranged in an electromagnetic cluster in a predefined section of a respective arm of the star-shaped arrangement, in particular in each case in the same/the same predefined section, in particular at a distance from the central welding processing point of at least 450 mm, in particular in an equilateral triangular arrangement with a side length of at least 650 mm (in particular with an absolute corresponding spatial extension of the resistance welding device of approx. 2,500 mm), the respective electromagnetic cluster in the plan view preferably having an extension of has a maximum of 250mm. Such proportions, which are only mentioned here as examples and can be scaled as desired, already provide a noticeable improvement in quality compared to welds using previously known systems with a good compromise between the outlay in terms of system technology and the electromagnetic effect.

Apart from the fact that an access or window for loading or removing material is to be planned, the dimensions can preferably be planned as small as possible.

According to one embodiment, the redundant electromagnetic components are each arranged in an electromagnetic cluster, with a connecting line under the clusters (each between paired clusters) forming a preferably equilateral triangular arrangement, with the respective connecting line preferably running at least in sections outside the system boundaries, in particular at least in Section abeam from the central weld processing point.

According to one embodiment, the central weld processing point is at the centroid of a triangular arrangement formed by three lines connecting three electromagnetic cluster(s) of the resistance welder. Last but not least, this type of symmetry provides a particularly effective leveling out of disadvantageous electromagnetic influences

According to one embodiment, an access or compartment, e.g. for a fan or similar accessories, and/or an operating cabinet/panel is/are arranged on the respective arm (or on the respective column), in particular on a radially outer side. As a result, the respective cluster can remain individually accessible and individually maintained or otherwise operated or supplemented. In addition, other components provided in the control cabinet (or in any compartment or compartment for accessories) can also be arranged comparatively far radially on the outside, ie at a great distance from the central processing point.

According to one exemplary embodiment, the redundant electromagnetic components are each arranged in an electromagnetic cluster relative to one another in such a way that additional electromagnetic shielding from one another and/or in relation to the central welding processing point is unnecessary. Last but not least, this also enables a lean system design. Optionally, the clusters can be (electromagnetically) shielded from the neighboring clusters or electromagnetic components and/or from the central welding processing point by means of at least one shield. This provides further advantages in connection with an electromagnetic optimization. The shielding can also be integrated into parts of the system housing, for example. However, a/the shielding remains only an optional further measure that should not be necessary in many applications.

According to one exemplary embodiment, the redundantly provided electromagnetic components are arranged symmetrically around the central welding processing point, namely both at the same radial distance (horizontal offset) and with the same angular offset relative to one another. This can improve the electromagnetic optimization even further.

According to one exemplary embodiment, the resistance welding device is coupled to a switch cabinet via a power supply line. Last but not least, the separate arrangement of the control cabinet and optionally also the energy unit also enables further electromagnetic optimization.

According to one embodiment, the resistance welding device has a sensor system that is at least threefold redundant in accordance with the at least threefold redundancy of the electromagnetic components (redundancy of the sensor system corresponding to redundancy of the EM components), at least comprising first, second and third sensor units, in particular for current measurement on the redundant EM components, the at least threefold redundant sensor system being coupled to the control/regulation unit. Last but not least, this also enables central control/regulation based on a plurality of individual measured values of the same welding parameter.

The aforementioned object is also achieved by using an electrical/electronic interconnection of first, second and third electromagnetic components to provide the energy required for resistance welding, in particular for KE welding, and to provide (at least) triple redundancy of these electromagnetic components (triple presence of the same components), in a relative spatial arrangement to one another in a resistance welding device for compensating or leveling electromagnetic influences with regard to a centrally arranged welding processing point of the resistance welding device, in particular in a rotationally symmetrical arrangement of the redundant components with a horizontal angle offset of 120° relative to each other in/by means of a resistance welding device previously described above. As a result, the aforementioned advantages can be realized, in particular with regard to the high quality of the welded connection in the case of particularly thick materials or particularly large welded connection diameters or particularly energy-intensive welds.

The aforementioned object is also achieved by a resistance welding method, in particular KE resistance welding method, in which electromagnetic components coupled to an energy unit of a resistance welding device, in particular transformers (groups), provide the welding energy required for resistance welding at welding electrodes, and in which a compressive force unit provides the compressive force required for resistance welding on the joining partners to be welded; with at least threefold redundancy of the electromagnetic components, the welding energy is provided via at least three arms or columns which are arranged in a star-shaped arrangement around a centrally arranged welding processing point are arranged, wherein the electromagnetic components are arranged in a relative spatial arrangement to each other to compensate for electromagnetic influences with respect to the centrally arranged welding processing point, in particular in a resistance welding device previously described above. As a result, the aforementioned advantages can be realized, in particular with regard to an optimized uniform distribution of the EM field or the magnetic field in the area of the joint (welding processing point).

According to one embodiment, the redundantly provided electromagnetic components are arranged symmetrically around the central welding processing point, namely both at the same radial distance (r) and with the same angular offset (α) relative to one another (angular offset in particular in a horizontal plane around the welding processing point, i.e. in plan view). This can further optimize the mutual leveling of EM influences, in particular in such a way that no (at least no noticeably disadvantageous) EM inhomogeneity is recorded in the central welding processing point.

According to one embodiment, the welding energy is provided via exactly three arms or columns, which form a star-shaped tripod portal around the central welding processing point, in particular with an angular offset of at least approximately 120° to one another, preferably with a rotationally symmetrical arrangement of the arms or columns around the central welding processing point. Last but not least, this also enables a good compromise to be made between the outlay in terms of plant/process engineering and the benefit with regard to the achievable advantages described here.

According to one embodiment, the resistance welding process is controlled in an at least partially automated manner and optionally also carried out in a regulated manner, with a material supply from joining partners also being optionally regulated in terms of time depending on the operating state of the redundant electromagnetic components, in particular in such a way that the joining partners are already arranged in the central welding processing point before the redundant electromagnetic components for the resistance welding function are operated. This enables further advantages to be realized in connection with the handling of the workpieces in an at least partially automated process.

According to one embodiment, the method includes an at least triple redundant sensory detection of at least one welding parameter comprising the welding current and optionally also at least one time value (welding time, current times, current as a function of time), in particular by means of first, second and third sensor units coupled to the respective redundant EM component and to the control/regulation unit. On the one hand, this favors an individual recording of the at least one welding parameter for each EM component and, on the other hand, it can also provide a common welding parameter (e.g. an averaged measured current value), which can optionally also be used to control/regulate the welding process, in particular to optimize the type of capacitor discharge or capacitor charging. The sensors also enable workpiece-related documentation.

In this case, the individual measured current values (or corresponding further parameters) of the redundant EM components can be averaged to form a single measured current value, and an averaged measured current value is processed further. Optionally (alternatively or additionally) at least one documentation or monitoring of the welding process is carried out within the framework of an addition of individual welding curves (or their progressions).

According to one exemplary embodiment, the method includes a control/regulation based on at least one welding parameter including the welding current, the at least one welding parameter being detected by means of at least triple redundant sensor units on the respective redundant EM component. This also enables welding parameters to be documented and optionally also active control/regulation of the welding process based on the corresponding measured values, in particular current measured values.

The aforementioned object is also achieved by a control/regulation unit set up for controlling or regulating a resistance welding device in a resistance welding method described above, in particular set up for controlling/regulating the provision of the energy required for resistance welding, in particular for KE welding, with at least threefold redundancy of the electromagnetic components of the resistance welding device in a relative local arrangement with respect to a/the centrally arranged welding processing point. As a result, the aforementioned advantages can be realized, in particular with regard to an expansion of existing systems in terms of control/regulation technology. For example, the control/regulation unit can be installed as a kind of "black box" in a respective system and can be updated or maintained separately from the other system components for example with regard to a quality monitoring function (quality optimization of fully automated welds). Here, the control unit is provided for a resistance welding device according to the present disclosure.

The control/regulation unit is preferably set up for fully automated control/regulation of the resistance welding process on a single pair of joining partners and optionally also for a series of a large number of joining partners, which are fed to the central welding processing point, for example by means of a robot (or manually). Depending on the application, the functionality of the control/regulation unit can also be expanded with regard to the control/regulation of at least one robot for (logistical) handling (material supply/removal) of semi-finished products and workpieces or joining partners or workpieces that are already firmly connected to one another. Optionally, the control/regulation unit also has a wireless and/or wired communication module, by means of which the control/regulation unit can be addressed via a network (data exchange, signal transmission, control/regulation specifications). The control/regulation can in particular also be designed as an active control/regulation based on at least one welding parameter recorded on or in connection with the EM components. The corresponding sensors, in particular current sensors, can also be in direct communication with the control/regulation unit.

The aforementioned object is also achieved by a computer program product comprising instructions which, when the computer program product is executed on a computer, cause the computer to control or regulate a resistance welding method described above using the computer, in particular a computer program product set up to control/regulate the provision of the energy required for resistance welding, in particular for KE welding, with at least threefold redundancy of the electromagnetic components of the resistance welding device in a relative local arrangement with respect to a/the centrally arranged welding processing point. As a result, the aforementioned advantages can be realized, in particular with regard to retrofitting existing systems (functional expansion, conversion). Depending on whether a respective system is equipped with a separately provided control/regulation unit or whether, for example, remote control is to take place via a network, the computer program product can at least partially replace the functionality of the control/regulation unit, for example also in connection with process automation. The computer program product is optionally implemented in the control/regulation unit. For example, the computer program product is provided at least for standard process steps without active control based on (instantaneous) sensor measurement data. Thereby, the computer program product is provided for a resistance welding device according to the present disclosure.

Summary: The present invention relates to a resistance welding device optimized with regard to (electro)magnetic fields in an electromagnetically optimized arrangement and a corresponding resistance welding method, in particular a resistance welding device comprising: electromagnetic components coupled/coupable to an energy unit designed to provide the welding energy required for resistance welding, in particular at least comprising the following components: transformer (group); welding electrodes; a compressive force unit set up to provide the compressive force required for resistance welding on the joining partners to be welded; a control/regulation unit configured to control/regulate the resistance welding process; wherein the resistance welding device in plan view has at least three arms or columns in a star-shaped arrangement with at least threefold redundancy of the electromagnetic components around a centrally arranged welding processing point. In particular, this also provides advantageous (electro)magnetic conditions in the area of the joint in the central welding processing point.

character list

• 1 in einer perspektivischen Seitenansicht in schematischer Darstellung eine Widerstandsschweißvorrichtung gemäß einem Ausführungsbeispiel;
• 2A, 2B, 2C, 2D, 2E in mehreren perspektivischen Ansichten und Seitenansichten und in einer Draufsicht eine Widerstandsschweißvorrichtung gemäß einem Ausführungsbeispiel;
• 3 in schematischer Darstellung eine Widerstandsschweißvorrichtung gemäß Ausführungsbeispielen, mit dreifacher Redundanz;
• 4 in schematischer Darstellung eine Widerstandsschweißvorrichtung gemäß Ausführungsbeispielen, mit vierfacher Redundanz;

The invention is described in more detail in the following drawing figures, reference being made to the other drawing figures for reference symbols which are not explicitly described in a respective drawing figure. Show it:

• 1 in a perspective side view in a schematic representation of a resistance welding device according to an embodiment;
• 2A , 2 B , 2C , 2D , 2E in several perspective views and side views and in a plan view, a resistance welding device according to an embodiment;
• 3 a schematic representation of a resistance welding device according to exemplary embodiments, with triple redundancy;
• 4 a schematic representation of a resistance welding device according to exemplary embodiments, with fourfold redundancy;

DETAILED DESCRIPTION OF THE FIGURES

The invention will first be explained with general reference to all reference numerals and figures. Special features or individual aspects or aspects of the present invention that are clearly visible/representable in the respective figure are addressed individually in connection with the respective figure.

A resistance welding device 10 is provided, comprising: electromagnetic components 12 coupled/coupable to an energy unit 11, which are provided redundantly in triplicate (first, second and third electromagnetic components 12a, 12b, 12c), in particular comprising or at least having transformers (groups). The energy unit can be used to carry out energetic/electrical measures in an arrangement between an energy supply or an energy/electricity network and the electromagnetic components or transformers. In this respect, coming from the network side, the energy flow is branched/distributed threefold to the respective redundant component 12 (in particular transformers). The energy required for welding is then provided in a second step by means of the electromagnetic components 12 on welding electrodes 13, 13a, 13b, which act on the joining partners to be joined in a centrally arranged welding processing point M, wherein a compressive force on the joining partners can be provided by means of a compressive force unit 15 acting on at least one of the welding electrodes (in particular comprising an adjustment unit). The release of energy and the development of compressive force can optionally be controlled/regulated by means of a control/regulation unit 17, in particular using appropriate sensors that are known to the person skilled in the art. The system 10 has a star-shaped structure by providing at least three arms 19 or columns, on which the redundant electromagnetic components 12 are provided, namely first components 12a on a first arm 19a or on a first column, second components 12b on a second arm 19b or on a second column, and third components 12c on a third arm 19c or on a third column. The electromagnetic components are triple redundant, preferably arranged or combined in a cluster 12.1 on the respective arm, at a radial distance from the central welding point M. The arms preferably form a symmetrical triangular arrangement in plan view with an angular offset α of 120° between the arms. One or more control cabinets are preferably arranged outside of the system 10 shown here and are coupled to the system via a power supply line 3 . Access points or compartments 16 for e.g. fans or similar accessories are arranged on the free ends of a respective arm 19, whereby an operating cabinet/panel can optionally also be provided. A window 18 is preferably formed between two arms 19 in each case, at which a person/skilled worker 1 or processing robot gains access to the central welding point M.

A system housing 14 that protects in particular against high voltage is provided on the respective arm. Optionally, additional electromagnetic shielding can also be provided in the hood 14 or in the corresponding housing parts, in particular provided by means of housing elements on the respective arm, as in 1 implied. For example, the respective cluster 12.1 is electromagnetically shielded on at least three, preferably on four sides (ie in all horizontal directions) and optionally also on the top and/or bottom by means of shielding elements.

A computer program product 20 can make specifications for the welding process, in particular in connection with the control/regulation unit 17.

The resistance welding device 10 preferably has redundant sensors 30, in particular for an (individual) current measurement at the respective redundant EM component; for example, first, second and third sensor units 30a, 30b, 30c are provided, which are coupled to the first, second and third EM components (in particular transformers (groups)).

The following geometric characteristics make it easier to understand the invention: horizontal offset r or radial distance between the central welding processing point M and the respective cluster 12.1; leg or side s of an equilateral triangle arrangement (connecting line between centers of the respective cluster); Section sd of connecting line s, which runs outside the plant boundaries; central machining axis z13 of the welding electrodes running through the machining point M; Longitudinal direction x, transverse direction y, vertical direction z (vertical axis), horizontal plane xy (plane according to top view), angular offset α around the welding processing point or around the processing axis z13, in top view, in particular 120° between the individual arms.

In 1 the star-shaped structure of a device 10 according to the invention is shown having three arms 19a, 19b, 19c. The three arms first The central welding processing point M is accessible, eg for a robot and/or for a person, in a lateral area between each two of the arms.

In the 2 Details of the device-technical structure of the system 10 according to the invention are shown. The outer lateral surface of the device 10 has a star-shaped contour in a plan view, with the individual arms extending radially outward in a rectangular shape, and with a rounded, continuous smooth transition between pairs of arms (concave curvature of the outer lateral surface).

In 2A In particular, an identical structure or an identical mirror-image arrangement of housing/system components is also shown on the respective arm 19 . The energy unit 11 can be coupled to all three clusters 12.1 formed by the redundant electromagnetic components 12. Optionally, several energy units can also be provided. However, central control/regulation via only one energy unit is preferably provided.

In 2 B the welding electrodes 13a, 13b and the pressure force unit are indicated, which are accessible via a/the window 18 between the corresponding arms, in particular for the purpose of supplying semi-finished products/joining partners.

In 2C In particular, the structure of the system 10, which is symmetrical in the transverse/longitudinal direction, can also be seen. The rotational symmetry is ensured about a/the central axis z13.

In 2D In particular, the comparatively large free space between the central welding processing point and the respective cluster can also be seen, i.e. the comparatively large radial offset r of the electromagnetically acting components relative to the central welding processing point M in relation to the overall system dimensions.

In 2E In particular, the relative arrangement of the redundant electromagnetic components 12 relative to one another is illustrated. The three redundant clusters 12.1 are at a distance s relative to each other in the manner of an equilateral triangle (angular offset of 120°, with in 2E the complementary angle α is shown (60°)) arranged at an identical radial distance r to the central weld point M. The dotted line indicated around the respective cluster can illustrate an EM field whose range is system- and power-specific. According to the view 2E corresponds to a section along the in 2D indicated horizontal plane xy.

In 3 the arrangement or the functional interaction of redundant sensors 30 in particular for current measurement at the redundant EM components is indicated. The sensors can be equipped with active control/regulation functions depending on the desired implementation/characteristic. First, second and third sensor units 30a, 30b, 30c are preferably provided on the individual EM components 12a, 12b, 12c, which include at least one current measuring function. The redundant sensor system 30 is connected/coupled (in 3 For the sake of a better overview, this is only indicated for the third sensor unit 30c by a dotted line). In this way, instantaneous measured values can also be taken into account directly in a control/regulation, for example as part of quality optimization measures in fully automated production with very short cycle times. At least one documentation for the purpose of subsequent tracing and reproducibility of the individual production steps can be simplified by the redundant sensors. The control/regulation unit 17 can have a data memory for the workpiece-related filing/storage of process parameters.

In 4 a quadruple redundancy is shown roughly schematically. The individual arms 19a, 19b, 19c form a cross-shaped arrangement with two portals spanning the central joint, with an identical angular offset (symmetrical arrangement). 4 shows the scalability. The fourth (or optionally further) redundant EM component (and analogously the corresponding arm 19) is in 4 only marked with the number-independent reference number 12.

Reference List

1

human/skilled worker

3

power supply line

10

resistance welding device

11

energy unit

12

electromagnetic component, especially transformer (group)

12a

first electromagnetic component, in particular first/r transformer (group)

12b

second electromagnetic component, in particular second transformer (group)

12c

third electromagnetic component, in particular third transformer (group)

12.1

electromagnetic cluster

13, 13a, 13b

welding electrodes

14

Hood, optionally with integrated shielding

15

Compressive force unit, in particular comprising a repositioning unit

16

Access or compartments for e.g. fans or similar accessories

17

control/regulation unit

18

Window

19, 19a, 19b, 19c

arms or pillars

20

computer program product

30

redundant sensors, especially for current measurement on the redundant EM components

30a, 30b, 30c

first, second and third sensor unit

M

central welding processing point

right

Horizontal offset or radial distance

s

Leg/side of an equilateral triangle arrangement

sd

Section running outside the plant boundaries

z13

Machining axis of the welding electrodes

x

longitudinal direction

y

transverse direction

e.g

vertical direction (vertical axis)

xy

Horizontal plane, Plane view plane

a

Angular offset around the welding processing point, in particular 120° in plan view

Claims (17)

Resistance welding device (10) having: - electromagnetic components (12) which are/can be coupled to an energy unit (11) and are set up to provide the welding energy required for resistance welding; - welding electrodes (13); - a compressive force unit (15) set up to provide the compressive force required for resistance welding on the joining partners to be welded; - a control/regulation unit (20) set up for controlling/regulating the resistance welding process; characterized in that the resistance welding device (10) in plan view has at least three arms (19) or columns in a star-shaped arrangement with at least threefold redundancy of the electromagnetic components (12) around a centrally arranged welding processing point (M), the electromagnetic components (12) being arranged in a relative spatial arrangement to one another to compensate for electromagnetic influences with regard to the centrally arranged welding processing point (M). Resistance welding device (10) after claim 1 , wherein the resistance welding device (10) forms a star-shaped portal around the central welding processing point (M), the individual arms (19) or columns of the star-shaped portal each receiving at least the following electromagnetic component (12, 12a, 12b, 12c): transformer (group); and/or wherein the resistance welding device (10) forms a star-shaped portal with triple or quadruple redundancy of the electromagnetic components (12) around the central welding processing point (M). Resistance welding device (10) according to one of the preceding claims, wherein the resistance welding device (10) forms a star-shaped tripod portal around the central welding processing point (M), in which the individual arms or columns (19) are arranged at an angle (α) of at least approximately 120° to one another in plan view, i.e. with an at least approximately rotationally symmetrical arrangement around the central welding processing point (M). Resistance welding device (10) according to one of the preceding claims, wherein the resistance welding device (10) between at least two of the arms (19) or columns of the star-shaped arrangement has a window (18) for access for a processing robot or people to the central welding processing point (M), in particular at least three windows for access between all mutually adjacent arms or columns or between each two of the arms or columns. Resistance welding device (10) according to one of the preceding claims, wherein the redundant electromagnetic components (12) are each arranged in an electromagnetic cluster (12.1) in a predefined section of a respective arm (19) of the star-shaped arrangement, in particular in the same / the same predefined section; and/or wherein the redundant electromagnetic components (12) are each arranged in an electromagnetic cluster (12.1), wherein a connecting line (s) under the clusters (12.1) forms a preferably equilateral triangular arrangement, wherein the respective connecting line (s) preferably runs at least in sections outside of the system boundaries, in particular at least in section (sd) transversely from the central welding processing point (M); and/or wherein the central welding processing point (M) lies in the focus of a triangular arrangement formed by three lines (s), which lines (the) connect three electromagnetic clusters (12.1) of the resistance welding device (10). Resistance welding device (10) according to one of the preceding claims, wherein an access or compartment (16) and/or a control cabinet/panel is arranged on the respective arm (19), in particular on a radially outer side. Resistance welding device (10) according to one of the preceding claims, wherein the redundant electromagnetic components (12) are each arranged in an electromagnetic cluster (12.1) relative to one another in such a way that additional electromagnetic shielding from one another and/or in relation to the central welding processing point (M) is unnecessary. Resistance welding device (10) according to one of the preceding claims, wherein the redundantly provided electromagnetic components (12) are arranged symmetrically around the central welding processing point (M), namely both at the same radial distance (r) and with the same angular offset (α) relative to one another. Resistance welding device (10) according to one of the preceding claims, wherein the resistance welding device (10) is coupled to a switch cabinet via a power supply line (3). Resistance welding device (10) according to one of the preceding claims, wherein the resistance welding device (10) has at least threefold redundant sensors (30) according to the at least threefold redundancy of the electromagnetic components (12), at least comprising first, second and third sensor units (30a, 30b, 30c), in particular for a current measurement on the redundant electromagnetic components (12), the at least threefold redundant sensor system being coupled to the control/regulation unit (17). Use of an electrical/electronic interconnection of first, second and third electromagnetic components (12, 12a, 12b, 12c) to provide the energy required for resistance welding and to provide at least triple redundancy in a spatial arrangement relative to one another in a resistance welding device (10) to compensate for electromagnetic influences with regard to a centrally arranged welding processing point (M) of the resistance welding device (10). Resistance welding method in which electromagnetic components (12) coupled to an energy unit (11) of a resistance welding device (10) provide the welding energy required for resistance welding at welding electrodes (13), and in which a compressive force unit (15) provides the compressive force required for resistance welding on the joining partners to be welded; the welding energy being provided with at least threefold redundancy of the electromagnetic components (12) via at least three arms (19) or columns which are arranged in a star-shaped arrangement around a centrally arranged welding processing point (M), the electromagnetic components (12) being arranged in a relative spatial arrangement to one another on the Compensation of electromagnetic influences with respect to the centrally arranged welding processing point (M) are arranged, in particular in a resistance welding device (10) according to one of Claims 1 until 10 . Resistance welding method according to the preceding claim, wherein the redundantly provided electromagnetic components (12) are arranged symmetrically around the central welding processing point (M), namely both at the same radial distance (r) and with the same angular offset (α) relative to one another. Resistance welding method according to one of the two preceding claims, wherein the welding energy is provided via exactly three arms (19) or columns, which form a star-shaped tripod portal around the central welding processing point (M), in particular with an angular offset (α) of at least approximately 120° to one another, preferably with a rotationally symmetrical arrangement of the arms (19) or columns around the central welding processing point (M); and/or the resistance welding process being controlled in an at least partially automated manner and optionally also being carried out in a regulated manner, with the material supply of joining partners optionally also being regulated in terms of time depending on the operating state of the redundant electromagnetic components, in particular in such a way that the joining partners are already arranged in the central welding processing point before the redundant electromagnetic components for the resistance welding function are operated. Resistance welding method according to one of the three preceding claims, wherein the method comprises at least triple redundant sensory detection of at least one welding parameter comprising the welding current, in particular by means of first, second and third sensor units (30a, 30b, 30c) coupled to the respective redundant electromagnetic component (12a, 12b, 12c) and to the control/regulation unit (17); and/or wherein the method comprises a control/regulation based on at least one welding parameter comprising the welding current, wherein the at least one welding parameter is detected by means of at least triple redundant sensor units (30a, 30b, 30c) on the respective redundant electromagnetic component (12a, 12b, 12c). Control/regulation unit (17) set up for controlling or regulating a resistance welding device (10) in a resistance welding method according to one of the preceding method claims, set up for controlling/regulating the provision of the energy required for resistance welding with at least triple redundancy of the electromagnetic components (12) of the resistance welding device (10) in a relative spatial arrangement with respect to a/the centrally arranged welding processing point (M), the control/regulation unit (17) for a resistance welding device ( 10) after one of Claims 1 until 10 is provided. Computer program product (20) comprising instructions which, when the computer program product is executed on a computer, cause the computer to control or regulate a resistance welding method according to one of the preceding method claims by means of the computer, the computer program product being set up to control/regulate the provision of the energy required for resistance welding with at least threefold redundancy of the electromagnetic components (12) of a/the resistance welding device (10) in a relative spatial arrangement with respect to a/the centrally arranged welding processing point (M), wherein the computer program product (20) for a resistance welding device (10) according to one of Claims 1 until 10 is provided.

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