Method for producing a resistor arrangement having a contact element, and resistor arrangement having a contact element
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- WIELAND WERKE AG
- Filing Date
- 2024-05-16
- Publication Date
- 2026-04-22
Smart Images
Figure EP2024063481_19122024_PF_FP_ABST
Abstract
Description
[0001] Description
[0002] Method for producing a resistor arrangement with a contact element and resistor arrangement with a contact element
[0003] The invention relates to a method for producing a resistor arrangement with a contact element, as well as to a resistor arrangement with a contact element. Such a resistor arrangement can be used in a device for measuring the strength of an electric current.
[0004] Current measurements in electronic circuits are carried out using measuring resistors connected in series with the component to be monitored. The current is determined according to Ohm's law from the voltage drop across the shunt resistor. The resistance value is assumed to be known. Accurate and reliable current measurement is particularly important, for example, in the battery management system of an electric or hybrid vehicle. A resistor assembly comprising such a low-ohm measuring resistor of approximately 10 to 100 pOhm and terminals for connecting the resistor assembly to the circuit can be manufactured from a longitudinally welded composite material. This is known, for example, from document EP 0 605 800 A1.The composite material is manufactured from three metal strips, each of which is joined to one another via a longitudinal seam using an electron beam or laser welding process. The middle metal strip consists of a material with a very low temperature coefficient of resistance. This material forms the actual resistance element of the measuring resistor. The two outer strips are usually made of a material with high electrical conductivity, such as copper. Such materials usually have a high temperature coefficient of resistance compared to the material of the resistance element. These two outer strips form connection elements, via which the measuring resistor can be connected to an electrical circuit.
[0005] The voltage drop across a measuring resistor is tapped via contact pins or similar elements, which are usually arranged on the connection elements on both sides of the measuring resistor. Such contact pins can be soldered, pressed, or welded onto the connection elements of the resistor array. The voltage is recorded and further processed by measurement and evaluation electronics. Electronic components are provided for this purpose, which can be arranged on a circuit board. The circuit board can be located in the immediate vicinity of the resistor array.
[0006] A resistor assembly with a low-ohm current measuring resistor is known from DE 10 2009 031 408 A1. This resistor assembly features terminals for tapping the voltage. These terminals are formed by embossing and threading in the plate-shaped sections used to connect the resistor assembly to the external circuit. The measuring leads for voltage measurement are connected to the terminals using cable lugs and fastening screws.
[0007] Furthermore, the document US 10 163 553 B2 discloses a
[0008] A resistor assembly with two plate-shaped elements for connecting the resistor assembly to an external circuit and a strip-shaped resistor element is known. On either side of the resistor element, each of the two connecting elements has a hole into which a contact pin is inserted. The contact pins are separate components that must be specially manufactured and added to the resistor assembly.
[0009] These prior art devices require additional components to measure the voltage drop across the measuring resistor. This requires additional effort and expense. Furthermore, contact voltages can occur at the contact points of the individual components, which can distort the voltage signal.
[0010] A method for producing a resistor assembly with contact pins is known from DE 10 2020 003 458 A1. The contact pins are formed from the material of a terminal element by stamping or extrusion. A punch penetrates the material of the terminal element on one side of the terminal element and transfers the material into a second tool, designed as a negative mold, on the other side of the terminal element.
[0011] The invention is based on the object of specifying an alternative, in particular flexible method for producing a resistor arrangement with a contact element for measuring the current intensity and a resistor arrangement with such a contact element.
[0012] The invention is defined with respect to a method by the features of claim 1 and with respect to a resistor arrangement by the features of claim 9. The further dependent claims relate to advantageous embodiments and developments of the invention. The invention relates to a method for producing a resistor arrangement with a contact element, wherein the method comprises the following steps: a) providing a resistor arrangement comprising at least one material, b) immersing a tool into the material of the resistor arrangement on a processing side of the resistor arrangement or on an end face of the resistor arrangement adjacent to the processing side, c) partially separating, in particular partially cutting out, material from a material layer located on the processing side of the resistor arrangement, so that at least one material projection is formed on the processing side of the resistor arrangement,which remains monolithically connected to the material of the resistor arrangement in a connecting region and which has a free end which is located diametrically opposite the connecting region, d) bending the material projection into an upright position so that a contact element for tapping an electrical signal is formed.
[0013] The invention is based on the idea of forming one or more contact elements on a resistor arrangement using material from the resistor arrangement. A resistor arrangement used as a shunt resistor for measuring current intensities comprises at least one resistance element. Furthermore, it preferably comprises at least one connection element, particularly preferably two connection elements, for connecting the resistor arrangement to an electrical circuit. In these preferred cases, the at least one resistance element on the one hand and the at least one connection element on the other hand consist of different materials, usually metallic materials. The specific electrical resistance of the material of the resistance element can be at least a factor of 10 greater than the specific electrical resistance of the material of the connection element.On the other hand, the magnitude of the temperature coefficient of resistance of the terminal element material is much larger, typically at least a factor of 50, than the magnitude of the temperature coefficient of resistance of the resistive element material. In particular, the magnitude of the temperature coefficient of resistance of the resistive element material can be less than 5 10'. 5 1 / K, while the resistance temperature coefficient of the material of the connecting element is approximately 4 10' 31 / K. The connection element of the resistor arrangement can be made of copper, a preferably low-alloy copper alloy, aluminum, or a preferably low-alloy aluminum alloy, or can comprise at least one of these materials. The resistor element can be made of a copper alloy, which is commonly used as a resistor alloy. The connection element and the resistor element are mechanically and electrically connected to one another at a joint seam.
[0014] A contact element is formed on a processing side of the resistor arrangement by partially separating, in particular cutting out, material from a material layer of the resistor arrangement comprising the surface and then lifting or straightening it. For this purpose, a tool is immersed in the material of the resistor arrangement on the processing side of the resistor arrangement or on an end face of the resistor arrangement adjacent to the processing side. The tool can therefore, for example, be immersed in the material of a connection element or in the material of a resistor element. The further movement of the tool partially separates material from a material layer that is located on the processing side of the resistor arrangement on the surface of the resistor arrangement, i.e. in particular on the surface of a connection element or on the surface of a resistor element.The tool only penetrates a short distance into the material of the resistor arrangement, so that only material from a material layer comprising the surface of the resistor arrangement, i.e. in particular a material layer comprising the surface of the connection element or a material layer comprising the surface of the resistor element, is cut out. Advantageously, the immersion depth of the tool can be a maximum of 35%, preferably a maximum of 30%, particularly preferably a maximum of 25% of the thickness of the resistor arrangement at the point of machining. The thickness of the machined material layer corresponds to the immersion depth of the tool. The material of the resistor arrangement that is located outside this material layer remains unmachined. The partial separation of the material is similar to a scraping process. In this way, a material projection is formed on the machining side of the resistor arrangement.Partial cutting, in particular partial removal, means in this context that the cutting is carried out in such a way that the material is not completely severed, but that at the end of the cutting process the resulting material projection remains monolithically connected to the resistor arrangement in a connection area. The connection area can also be referred to as the base point of the material projection. The material projection has a free end that is located diametrically opposite its base point. The free end is formed from material that was originally located at the point on the resistor arrangement at which the tool is immersed in the material of the resistor arrangement. The material projection is preferably elongated, particularly preferably pin-shaped, rod-shaped, needle-shaped or pin-shaped.
[0015] The material projection is erected by being bent in a bending zone. The bending zone can be identical to the connecting region, i.e., essentially spatially coincide with the connecting region, or it can be located between the connecting region and the free end of the material projection. The bending of the material projection preferably occurs such that at least a section of the material projection adjoining the free end is oriented essentially perpendicular to the surface of the resistor arrangement, i.e., in particular, perpendicular to the surface of the connecting element or perpendicular to the surface of the resistor element. In particular, the angle that this section of the material projection forms with the surface of the resistor arrangement can be at least 85°.In other words: material from one layer is partially separated from the remaining material and raised so that it forms a pin-like elevation above the surface of the resistor array. In this way, the elevation creates a contact element for tapping an electrical signal. To create multiple contact elements, process steps b), c), and d) are carried out multiple times, i.e., at different points on the resistor array. Using such contact elements, the resistor array can be connected, for example, to a printed circuit board (PCB) equipped with measurement and evaluation electronics. Alternatively, the contact elements can also be connected to electrical lines to connect the resistor array to a measuring device.
[0016] The movement of the tool, in particular the machining direction during the cutting process, can take any direction, in particular any angular position with respect to the joint seam or the main current flow direction. Preferably, the tool moves essentially perpendicularly toward the joint seam between the connection element and the resistance element during the cutting process. The recess formed in the material of the resistor arrangement during the cutting process then runs parallel to the direction of the main current flow and therefore distorts the current flow lines only slightly. Alternatively, the tool can also move essentially parallel to the joint seam between the connection element and the resistance element during the cutting process. This allows the formed contact element to be positioned as close as possible to the joint seam.
[0017] The geometric shape of the formed contact element can be designed by the shape of the tool used for the separation process. Because one side of the contact element corresponds to the original surface of the resistor arrangement, this side of the contact element has a flat shape. The contact element can preferably be pin-, rod-, or pin-shaped. The contact element can, for example, have the shape of a square with a width B, a thickness D and a length L. Typical values are 0.8 mm < B < 2 mm, 0.5 mm < D < 1.2 mm and 4 mm < L < 10 mm. The length L correlates with the height to which the contact element rises above the surface of the resistor arrangement.
[0018] Alternatively, the contact element can also be formed as a flat element. The contact element can even extend across the entire width of the resistor array. In this case, the material of the resistor array is machined and bent to form a flat surface across the entire width of the resistor array.
[0019] A first advantage of the manufacturing process described above is that the contact element is monolithically bonded to the material of the resistor array. At the connection point, no contact resistance or parasitic voltages, such as contact voltages or thermal voltages that can occur when using solder, arise. The process therefore reduces adverse influences on the electrical signal being tapped, thus contributing to improved measurement accuracy. Furthermore, no additional parts, such as separate contact pins, are required. Additional joining processes, such as pressing or soldering contact elements, are also eliminated. The process thus enables cost-effective production of voltage taps on a resistor array.
[0020] A further advantage of the process is that the contact element is machined from only a relatively thin layer of the resistor array material—relative to the thickness of the resistor array. The resistor array material beyond this layer remains unmachined. Because the machining depth is shallow, the current-carrying cross-section in the resistor array remains virtually unaffected. The current paths, and thus the equipotential lines, are deflected only slightly in the area of the contact elements. The taps for voltage measurement therefore have virtually no influence on the measurement result.
[0021] A particular advantage of the method is that the position of the contact element can be chosen very freely. In particular, the method allows contact elements to be positioned very close to the joint between a connection element and a resistance element. This is particularly important when the contact elements are attached to the connection elements of the resistor arrangement. In this case, the closer the contact elements are positioned to the joint seam, the smaller the proportion of the connection elements through which current flows is compared to the total path over which the voltage is tapped. The strong temperature dependence of the specific electrical resistance of the connection element material therefore has only a very minor effect on the TCR characteristics of the measuring device.
[0022] In a special version of the process, the contact element can be machined from the material of the resistance element. The advantage of this is that the measuring path, over which the measurement signal is tapped, runs exclusively within the material of the resistance element, eliminating any further interference from adjacent materials or interface effects. Such interference can arise, in particular, from the joint between the resistance element and the connection element.
[0023] In one embodiment of the method, the tool can be inserted at an angle to the surface of the resistor assembly, preferably at an angle to the surface of the connecting element or at an angle to the surface of the resistor element. An inclined insertion of the tool creates favorable conditions for separating material from the surface of the resistor assembly.
[0024] Within the scope of a special embodiment of this embodiment, the tool can be immersed at an angle of 5° to 60°, preferably up to 30°, against the surface of the resistor arrangement, i.e. preferably against the surface of the connection element or against the surface of the resistor element. In other words, the tool is immersed along an immersion direction that is inclined at an angle of 5° to 60°, preferably up to 30°, against the surface of the resistor arrangement, i.e. preferably against the surface of the connection element or against the surface of the resistor element. The tool is therefore immersed shallowly, i.e. at a slight incline, against the surface of the resistor arrangement. Shallow immersion supports the separation of material from just one material layer of the resistor arrangement.
[0025] Within the scope of a further embodiment of the method, in step d), the material projection can be bent around a bending axis that is oriented parallel to the surface of the resistor arrangement, preferably parallel to the surface of the connection element or the surface of the resistor element, and runs through the connection area. The connection area and the bending zone thus coincide. The material projection is thus bent directly at its base point. This forms a contact element with maximum height. Within the scope of a further embodiment of the method, the partial separation of material and the bending of the material projection can be performed using the same tool. This eliminates the need for a second tool. This simplifies the manufacturing process.
[0026] Within the scope of a further embodiment of the method, the partial separation, in particular the partial removal of material, can be carried out by means of a cutting, chiseling, peeling, plowing, or furrowing process. These processes can be used to specifically remove material from a material layer encompassing the surface and make it available for a simultaneous or subsequent bending process. Therefore, these processes are particularly suitable for carrying out the separation process within the scope of the method described above.
[0027] Within the scope of a particular embodiment of the method, the resistor arrangement can have at least one connection element and at least one resistance element, wherein the connection element and the resistance element are mechanically and electrically connected to one another at a joint seam, and steps c) and d) can be carried out such that the contact element is positioned directly at the joint seam. With this position of the contact elements, the path over which the voltage is tapped includes no section or only an extremely small section consisting of the material of the connection elements. The strong temperature dependence of the specific electrical resistance of the material of the connection elements thus no longer affects the TCR characteristic of the measuring device.
[0028] In a further embodiment of the method, the
[0029] The resistor arrangement may comprise at least one connecting element made of copper or a copper alloy, and after step d), the surface of the connecting element and / or the surface of a contact element formed on the connecting element may be coated with tin, a tin alloy, or silver. Such a coating protects against corrosion and ensures good contact.
[0030] With regard to further technical features and advantages of the method according to the invention, reference is hereby explicitly made to the explanations in connection with the resistor arrangement according to the invention as well as to the figures, the figure description and the exemplary embodiments.
[0031] A further aspect of the invention relates to a resistor arrangement for measuring the strength of an electric current. The resistor arrangement comprises at least one material and has at least one contact element. The contact element is machined on a processing side of the resistor arrangement from a material layer of the resistor arrangement located on the processing side of the resistor arrangement and is monolithically connected to the material of the resistor arrangement in a connection region. The contact element extends on the processing side from the connection region to a free end and has an upright section adjoining the free end. The contact element has a bending zone in the connection region and / or between the connection region and its free end.
[0032] Such a resistor arrangement can be manufactured using the method described above. The at least one contact element consists of material that is merely cut from a material layer surrounding the surface of the resistor arrangement, specifically in such a way that a monolithic connection exists between the contact element and the resistor arrangement in a connection region. The contact element is a material projection bent out from the surface of the resistor arrangement and has a free end. Consequently, the contact element has a bending zone in the connection region and / or between the connection region and the free end.
[0033] In a preferred embodiment, at least one section of the contact element adjacent to the free end is oriented substantially perpendicular to the surface of the resistor arrangement. In particular, the angle formed by this section of the contact element with the surface of the resistor arrangement can be at least 85°.
[0034] The resistor arrangement comprises at least one resistance element and optionally at least one connection element. The at least one resistance element and the optional connection element are made of different electrically conductive materials, preferably metallic materials. The connection element and the resistance element are mechanically and electrically connected to each other at a joint seam.
[0035] An advantage of the resistor array described above is that the contact element is monolithically connected to the resistor array. At the connection point, no contact resistance and no parasitic voltages, such as contact voltages or thermal voltages when using solder, arise. The resistor array is therefore designed to largely reduce adverse effects on the electrical signal being tapped. This contributes to improving measurement accuracy. Because the contact element is cut and bent out of a material used in the resistor array, no additional parts, such as separate contact pins, are required. Additional joining processes, such as pressing or soldering contact elements, are also eliminated. The voltage taps on the resistor array can thus be manufactured cost-effectively.
[0036] A further advantage of the resistor array is that the contact element is machined from only a relatively thin layer of material—relative to the thickness of the resistor array. The material of the resistor array located beyond this layer remains unmachined. Because the machining depth is shallow, the current-carrying cross-section in the resistor array remains virtually unaffected. The current paths, and thus the equipotential lines, are only slightly deflected in the area of the contact elements. The taps for voltage measurement therefore have virtually no influence on the measurement result.
[0037] Within the scope of one embodiment, the resistor arrangement, in particular the connection element or the resistor element, can have a recess on the machining side of the resistor arrangement, which recess begins at the contact element, i.e., extends from the contact element, and which essentially corresponds to the negative shape of the contact element. Such a recess occurs when the contact element is not machined entirely from the material of the resistor arrangement, but rather only from a portion of the surface of the resistor arrangement. This is the case, for example, when the contact element is pin-shaped, rod-shaped, needle-shaped, or pin-shaped. The recess is then essentially linear.The recess is limited to a material layer that encompasses the surface of the resistor arrangement, in particular the surface of the connection element or the surface of the resistor element. The depth of the recess is therefore less than the thickness of the resistor arrangement at the location of the contact element. The recess can, for example, have the shape of a groove, a furrow, a groove, or a channel. The cross-section of the recess can, for example, be V-shaped, U-shaped, or trapezoidal.
[0038] Within the scope of a special refinement of this embodiment, the recess can have a longitudinal axis oriented substantially perpendicular to the joint seam located between a connection element and the resistance element. The recess then runs parallel to the direction of the main current flow and therefore distorts the current flow lines only slightly.
[0039] In another embodiment, the material of the contact element can have a greater hardness in the bending zone than outside the bending zone. The cutting and bending process during machining of the contact element plastically deforms the material in the bending zone. This leads to a local hardening of the material in this area. Therefore, the material has a higher local strength and a higher hardness. This higher strength enables the positioning, accommodation, and assembly of additional components on the contact element, for example other electrical or electronic components such as a resistor, a switch, a relay, or a circuit board. Because the resistor arrangement with a monolithically connected contact element has an increased increase in strength in the bending zone, the resistor arrangement is also suitable for applications in which increased acceleration values and shock loads may occur.
[0040] Within the scope of a further embodiment, the resistor arrangement can have at least one connection element and at least one resistance element, wherein the connection element has a greater thickness than the resistance element, such that it forms a step against the resistance element on at least one side. The contact element is machined out on the side of the connection element that forms the step. In the region of the step, the current density is lower than in the other regions of the connection element. Therefore, the depression created by machining out the contact element influences the current paths and thus the equipotential lines less than if the contact element had been machined out on the opposite side of the connection element. The measurement accuracy is thereby improved.
[0041] With regard to further technical features and advantages of the resistor arrangement according to the invention, reference is hereby explicitly made to the explanations in connection with the manufacturing method according to the invention as well as to the figures, the figure description and the exemplary embodiments.
[0042] Embodiments of the invention are explained in more detail with reference to the schematic drawings, in which:
[0043] Fig. 1 a resistor arrangement without contact element
[0044] Fig. 2a to 2c a first embodiment of the method
[0045] Fig. 3a to 3c a second embodiment of the method
[0046] Fig. 4 shows a first embodiment of a resistor arrangement
[0047] Fig. 5 a second embodiment of a resistor arrangement
[0048] Fig. 6 a third embodiment of a resistor arrangement
[0049] Fig. 7 a fourth embodiment of a resistor arrangement
[0050] Corresponding parts are provided with the same reference numerals in all figures.
[0051] Fig. 1 shows a known resistor arrangement 2 without a contact element. A likewise plate-shaped resistor element 4 is arranged between the two plate-shaped connecting elements 3, 3'. The resistor element 4 is mechanically and electrically connected to a respective connecting element 3, 3' on two opposite sides via a joining seam 6, 6'. The joining seam 6, 6' can be a weld seam, for example. The two connecting elements 3, 3' each have a greater thickness than the resistor element 4, so that they each form a step 31, 31' against the resistor element 4. The two connecting elements 3, 3' can have means which serve to connect the resistor arrangement 2 to an external circuit. For reasons of clarity, such means are not shown in Fig. 1. The main current direction is perpendicular to the two joining seams 6, 6'.The plate-shaped connecting elements 3, 3' and the resistance element 4 each have a top side 21 and a bottom side. End faces 22 border the top and bottom sides. For the purposes of the following explanations, the top side 21 of the connecting elements 3, 3' or the top side 21 of the resistance element 4 serves as the processing side 21.
[0052] Fig. 2a to Fig. 2c schematically show the sequence of a first embodiment of the method. Shown are a connection element 3 and a resistance element 4 of a resistance arrangement 2 according to Fig. 1 in longitudinal section. Because the connection element 3 is thicker than the resistance element 4, it has a step 31 on one side against the resistance element 4. A tool 9, similar to a chisel, plunges its tip on a processing side 21 into the material of the connection element 3 at an angle of approximately 30°, measured against the surface of the connection element 3 (Fig. 2a). The processing side 21 is identical to the side of the connection element 3 that has the step 31. The material displaced by the immersion process forms a primary material projection 501 on the surface of the connection element 3 on the processing side 21.The immersion depth is selected such that the machined material layer is no thicker than the height of the step 31 that the connecting element 3 has against the resistance element 4. After immersion, the tool 9 is moved towards the end of the connecting element 3 adjacent to the resistance element 4 (Fig. 2b). As a result, a continuous piece of material is separated from the material of the connecting element 3, similar to a scraping process. The material forms a material projection 50 on the machining side 21, which can, for example, have the shape of a straight chip. Because the immersion depth of the tool 9 is significantly less than the thickness of the connecting element 3, only material that was originally located in a material layer encompassing the surface of the connecting element 3 is separated. The surface of the connecting element 3 opposite the machining side 21, i.e. its underside, remains undeformed and unmachined.The movement of the tool 9 is terminated before the tip of the tool 9 has reached the end of the connecting element 3. Thus, the material projection 50 is not completely severed, but remains monolithically connected to the connecting element 3 in a connecting region 51. The material projection 50 has a free end 52 diametrically opposite the connecting region 51. In the next step, the material projection 50 is brought into an upright position relative to the surface of the resistor arrangement by bending it (Fig. 2c). For this purpose, the tool 9 is raised from the separating position, which is shown in dashed lines in Fig. 2c, in a tilting movement. The tilting movement is shown in Fig. 2c by a curved arrow. Due to the tilting movement of the tool 9, the material projection 50 is bent about a bending axis that is oriented parallel to the surface of the connecting element 3 and runs approximately through the connecting region 51.This creates a bending zone 53 in the material projection 50, which in this embodiment spatially coincides with the connection area 51 or at least overlaps it to a large extent. The free end 52 and the bending zone 53 delimit an upright section 54 of the material projection 50, to which a longitudinal axis A can be assigned. In the case shown, the longitudinal axis A and thus the section 54 are oriented essentially perpendicular to the surface of the connection element 3. The upright material projection 50 forms a contact element 5, which serves as a tap for the voltage drop across the resistance element 4. The contact element 5 is positioned very close to the joint seam 6, so that the contribution of the connection element 3 to the total resistance of the measuring section is very small.By removing material from the material of the connecting element 3, a recess 7 remains in the connecting element 3 on the processing side 21, which corresponds to the negative shape of the contact element 5. The recess 7 is so shallow that its depth does not extend beyond the height of the step 31.
[0053] Fig. 3a to Fig. 3c schematically show the sequence of a second embodiment of the method. Shown are a connection element 3 and a resistance element 4 of a resistance arrangement 2 according to Fig. 1 in longitudinal section. Because the connection element 3 is thicker than the resistance element 4, it has a step 31 on one side against the resistance element 4. A tool 9, the front edge of which has a concave curvature, plunges its tip on a processing side 21 into the material of the connection element 3 at an angle of approximately 30°, measured against the surface of the connection element 3 (Fig. 3a). The processing side 21 is identical to the side of the connection element 3 that has the step 31. The material displaced by the immersion process forms a primary material projection 501 on the surface of the connection element 3 on the processing side 21.The immersion depth is selected such that the machined material layer is no thicker than the height of the step 31 that the connecting element 3 has against the resistance element 4. After immersion, the tool 9 is moved towards the end of the connecting element 3 adjacent to the resistance element 4 (Fig. 3b). As a result, starting from the primary material projection 501, a continuous piece of material is partially separated from the material of the connecting element 3. The material forms a material projection 50 on the machining side 21. Due to the concave curvature of the front edge of the tool 9, the material projection 50 has the shape of an at least partially bent chip. Thus, the material projection 50 is already brought into an upright position during the feed movement of the tool 9.Because the immersion depth of the tool 9 is significantly less than the thickness of the connecting element 3, only material that was originally located in a material layer encompassing the surface of the connecting element 3 is severed. The surface of the connecting element 3 opposite the processing side 21, i.e. its underside, remains undeformed and unmachined. The movement of the tool 9 is terminated before the tip of the tool 9 has reached the end of the connecting element 3 (Fig. 3c). Thus, the material projection 50 is not completely severed, but remains monolithically connected to the connecting element 3 in a connecting area 51. Diametrically opposite the connecting area 51, the material projection 50 has a free end 52. Since the material projection 50 has already been brought into an upright position during the feed movement of the tool 9, in contrast to the process shown in Fig.2, no tilting movement of the tool 9 is necessary to erect the material projection 50. Because the material projection 50 is continuously bent, the bending zone 53 extends over a wide area starting from the connection area 51 in the direction of the free end 52. In Fig. 3c, the bending zone 53 is indicated by a dashed ellipse. The upright section 54 of the material projection 50 adjoining the free end 52 and extending to the bending zone 53 is oriented essentially perpendicular to the surface of the connection element 3. The erected material projection 50 forms a contact element 5, which serves as a tap for the voltage drop across the resistance element 4. The contact element 5 is positioned very close to the joint seam 6, so that the contribution of the connection element 3 to the total resistance of the measuring section is very small.By removing material from the material of the connecting element 3, a recess 7 remains in the connecting element 3 on the processing side 21, which corresponds to the negative shape of the contact element 5. The recess 7 is so shallow that its depth does not extend beyond the height of the step 31.
[0054] Fig. 4 shows an oblique view of a first embodiment of a resistor arrangement 2 with two contact elements 5, 5', which are machined from the material of the two connection elements 3, 3', each on the side that has a step 31, 3T against the resistance element 4. The method described in connection with Fig. 2a to Fig. 2c can be used to manufacture the contact elements 5, 5', provided that correspondingly narrow tools 9 are used. The respective bending zones 53, 53' of the material projections 50, 50' largely coincide with the respective connection regions 51, 5T. The respective section 54, 54' between the bending zone 53, 53' and the free end 52, 52' is oriented perpendicular to the surface of the respective connection element 3, 3'. The two contact elements 5, 5' are positioned directly on the respective joining seam 6, 6'.The two connecting elements 3, 3' each have a groove-, trough-, or groove-like recess 7, 7', each extending from a contact element 5, 5' and essentially corresponding to the negative shape of the contact element 5, 5'. The recesses 7, 7' extend such that the longitudinal axis C, C' of each recess is oriented perpendicular to the joint seam 6, 6'.
[0055] Fig. 5 shows an oblique view of a second embodiment of a resistor arrangement 2 with two contact elements 5, 5', which are machined from the material of the two connection elements 3, 3', each on the side which has a step 31, 3T against the resistance element 4. The method described in connection with Fig. 3a to Fig. 3c can be used to produce the contact elements 5, 5', provided that correspondingly narrow tools 9 are used. The respective bending zones 53, 53' of the material projections 50, 50' extend over a wide area from the connection area 51, 51' in the direction of the free end 52, 52'. Analogous to Fig. 3c, the respective section 54, 54' between the bending zone 53, 53' and the free end 52, 52' is oriented perpendicular to the surface of the respective connection element 3, 3'. The two contact elements 5, 5' are positioned directly on the respective joint seam 6, 6'.The two connecting elements 3, 3' each have a groove-, trough-, or groove-like recess 7, 7', each extending from a contact element 5, 5' and essentially corresponding to the negative shape of the contact element 5, 5'. The recesses 7, 7' extend such that the longitudinal axis C, C' of each recess is oriented perpendicular to the joint seam 6, 6'.
[0056] Fig. 6 shows an oblique view of a third embodiment of a resistor arrangement 2 with two contact elements 5, 5', which are machined from the material of the resistor element 4. To produce the contact elements 5, 5', the method described in connection with Fig. 2 can be used in a correspondingly modified form, wherein correspondingly narrow tools 9 are used. The respective bending zones 53, 53' of the material projections 50, 50' largely coincide with the respective connecting regions 51, 51'. The respective section 54, 54' between the bending zone 53, 53' and the free end 52, 52' is oriented perpendicular to the surface of the respective connecting element 3, 3'. The two contact elements 5, 5' are positioned directly on the respective joining seam 6, 6'.The two connection elements 3, 3' each have a furrow-, trough-, or groove-like depression 7, 7', which each originates from a contact element 5, 5' and which essentially corresponds to the negative shape of the contact element 5, 5'. The depressions 7, 7' extend such that the longitudinal axis C, C' of each depression 7, 7' is oriented perpendicular to the joint seam 6, 6'. For reasons of clarity, the contact elements 5, 5' are shown in Fig. 6 such that the respective corresponding depressions 7, 7' are arranged offset from one another. However, it is also possible to choose an aligned arrangement of the depressions 7, 7'.
[0057] Fig. 7 shows an oblique view of a fourth embodiment of a resistor arrangement 2 with two contact elements 5, 5', which are machined from the material of the two connection elements 3, 3'. The embodiment shown in Fig. 7 differs from the embodiment shown in Fig. 4 essentially in that the machining direction is parallel to the joining seams 6, 6'. Accordingly, the recesses 7, 7' run such that the longitudinal axis C, C' of each recess 7, 7' is oriented parallel to the joining seam 6, 6'. It is also possible to modify the embodiment shown in Fig. 7 such that the contact elements 5, 5' are machined from the material of the resistor element 4.
[0058] List of reference symbols
[0059] 2 Resistor arrangement
[0060] 21 Editing page
[0061] 22 front side
[0062] 3, 3' connecting element
[0063] 31, 31" step
[0064] 4 resistance element
[0065] 5.5' contact element
[0066] 50, 50' material lead
[0067] 501 Material advantage
[0068] 51 , 51 ' connection area
[0069] 52, 52' free end
[0070] 53, 53' bending zone
[0071] 54, 54' section
[0072] 6, 6' joining seam
[0073] 7, 7' recess
[0074] 9 Tools
[0075] A Longitudinal axis
[0076] C, C longitudinal axis
Claims
Patent claims 1 . Method for producing a resistor arrangement (2) with a contact element (5, 5'), the method comprising the following steps: a) providing a resistor arrangement (2) comprising at least one material, b) immersing a tool (9) into the material of the resistor arrangement (2) on a processing side (21) of the resistor arrangement (2) or on an end face (22) of the resistor arrangement (2) adjacent to the processing side (21), c) partially separating material from a material layer located on the processing side (21) of the resistor arrangement (2), so that at least one material projection (50, 50') is formed on the processing side (21) of the resistor arrangement (2), which projection remains monolithically connected to the material of the resistor arrangement (2) in a connection region (51, 51') and which has a free end (52, 52') which is diametrically opposite the connection region (51, 5T) is located,d) bending the material projection (50, 50') into an upright position so that a contact element (5, 5') for tapping an electrical signal is formed., 2. Method according to claim 1, characterized in that the immersion of the tool (9) takes place obliquely to the surface of the resistor arrangement (2).
3. Method according to claim 2, characterized in that the immersion takes place at an angle of 5° to 60° against the surface of the resistance arrangement (2).
4. Method according to one of the preceding claims, characterized in that in step d) the material projection (50, 50') is bent about a bending axis which is oriented parallel to the surface of the resistor arrangement (2) and runs through the connecting region (51, 51').
5. Method according to one of the preceding claims, characterized in that the separation of material and the bending of the material projection (50, 50') are carried out by the same tool (9).
6. Method according to one of the preceding claims, characterized in that the partial separation of material is carried out by means of a cutting, chiseling, peeling, plowing or furrowing process.
7. Method according to one of the preceding claims, characterized in that the resistor arrangement (2) has at least one connection element (3, 3') and at least one resistance element (4), wherein the at least one resistance element (4) on the one hand and the at least one connection element (3, 3') on the other hand consist of different, electrically conductive materials, and wherein the connection element (3, 3') and the resistance element (4) are mechanically and electrically conductively connected to one another at a joining seam (6, 6'), and that steps c) and d) are carried out such that the contact element (5) is positioned directly on the joining seam (6, 6').
8. Method according to one of the preceding claims, characterized characterized in that the resistor arrangement (2) comprises at least one connection element (3, 3') made of copper or a copper alloy and that after step d) the surface of the connection element (3, 3') and / or the surface of a contact element (5, 5') formed on the connection element (3, 3') is coated with tin, a tin alloy or with silver.
9. Resistor arrangement (2) for measuring the strength of an electric current, wherein the resistor arrangement (2) comprises at least one material and has at least one contact element (5, 5'), which is machined on a processing side (21) of the resistor arrangement (2) from a material layer of the resistor arrangement (2) located on the processing side (21) of the resistor arrangement (2), is monolithically connected to the material of the resistor arrangement (2) in a connecting region (51, 51'), extends on the processing side (21) from the connecting region (51, 51') to a free end (52, 52') and has an upright section (54, 54') adjoining the free end, characterized in that the contact element (5, 5') in the connecting region (51, 51') and / or between the connecting region (51, 51') and its free end (52, 52') has a bending zone (53, 53').
10. Resistor arrangement (2) according to claim 9, characterized in that the resistor arrangement (2) has on the processing side (21) a recess (7, 7') which substantially corresponds to the negative shape of the contact element (5, 5') and which extends from the contact element (5, 5').
11. Resistor arrangement (2) according to claim 10, characterized in that the resistor arrangement (2) has at least one connection element (3, 3') and at least one resistance element (4), wherein the at least one resistance element (4) on the one hand and the at least one connection element (3, 3') on the other hand consist of different, electrically conductive materials, and wherein the connection element (3, 3') and the resistance element (4) are mechanically and electrically conductively connected to one another at a joining seam (6, 6'), and in that the recess (7, 7') has a longitudinal axis (C, C') which is oriented substantially perpendicular to the joining seam (6, 6').
12. Resistor arrangement (2) according to one of claims 9 to 11, characterized in that the material of the contact element (5, 5') has a greater hardness in the bending zone (53, 53') than outside the bending zone (53, 53').
13. Resistor arrangement (2) according to one of claims 9 to 12, characterized in that the resistor arrangement (2) has at least one connection element (3, 3') and at least one resistance element (4), wherein the at least one resistance element (4) on the one hand and the at least one connection element (3, 3') on the other hand are made of different, electrically conductive materials, wherein the connection element (3, 3') and the resistance element (4) are mechanically and electrically conductively connected to one another at a joint seam (6, 6'), and wherein the connection element (3, 3') has a greater thickness than the resistance element (4), so that it forms a step (31, 31') against the resistance element (4) on at least one side, and the contact element (5, 5') is machined out on the side of the connection element (3, 3') which forms the step (31, 31').