PRODUCTION METHOD FOR A RESISTOR, RESISTOR AND CORRESPONDING PRODUCTION INSTALLATION

Abstract

The invention concerns a manufacturing method for an electrical resistor (1), in particular for a low-resistance current measuring resistor, with the following steps (S1-S4): a) providing a plate-shaped base part (9) for the resistor (1), the base part (9) having a certain thickness and corresponding to the thickness a certain value of an electrical component characteristic (R), the thickness-dependent electrical component characteristic (R) preferably being the electrical resistance (1) of the base part (9), the sheet resistance or the transverse resistance, and b) rolling the base part (9) with a certain degree of rolling (AG), the thickness of the base part (9) decreasing in accordance with the degree of rolling (AG) and the value of the component characteristic (R) changing accordingly, c) measuring the thickness-dependent electrical component characteristic (R) on the rolled base part (9), and d) adaptation of the degree of rolling (AG) as a function of the measured electrical component characteristic (R), in particular in the context of a closed-loop control system with the electrical component characteristic (R) as controlled variable and the degree of rolling (AG) as control variable.

Furthermore, the invention includes an appropriately manufactured resistor and a corresponding production plant.

Claims

1. Method for manufacturing an electrical resistor comprising: a providing a plate-shaped base part for the resistor, the base part having a certain thickness and corresponding to the thickness a certain value of an electrical component characteristic rolling the base part with a certain degree of rolling, the thickness of the base part decreasing in accordance with the degree of rolling and the value of the component characteristic changing accordingly; measuring the thickness-dependent electrical component characteristic on the rolled base part; and adapting the degree of rolling as a function of the measured electrical component characteristic.

2. Method for manufacturing according to claim 1, wherein the base part is rolled in a rolling station, the component characteristic of the rolled base part is measured in a measuring station, and the base part is first conveyed by a conveying device through the rolling station and then through the measuring station.

3. Method for manufacturing according to claim 2, wherein the base part is continuously conveyed through the rolling station and then through the measuring station, and the thickness-dependent electrical component characteristic of the base part is measured without stopping the conveying movement of the base part in the measuring station, while the base part is conveyed through the measuring station.

4. Method for manufacturing according to claim 1, wherein the base part is a composite material strip comprising at least two material strips joined together along their longitudinal edges, and the composite material strip is rolled in the longitudinal direction of the strip in order to extend the composite material strip through the rolling,

5. Method for manufacturing according to claim 4, wherein the composite material strip is a tri-band consisting of three material strips joined together along their longitudinal edges, the outer material strips consisting of a conductor material, while the middle material strip consists of a resistor material.

6. Method for manufacturing according to claim 4, wherein the composite material strip is conveyed in the longitudinal direction of the strip through the rolling station and then through the measuring station, and the electrical resistance is measured in the measuring station transversely to the longitudinal direction of the strip.

7. Method for manufacturing according to claim 1, further comprising the following further step after rolling: separating the resistor from the base part in a separating station, in particular by punching in a punching station.

8. A resistor comprising a first connecting part made of a conductor material for introducing an electrical current into the resistor, a second connecting part of a conductor material for diverting the electrical current from the resistor, a resistance element made of a resistor material, the resistance element being arranged between the two connecting parts in the direction of current flow and through which the electrical current flows, and welds between the resistive element on the one hand and the connecting parts on the other hand, the welds being rolled, wherein the resistor has no adjustment incisions for resistance adjustment.

9. A resistor according to claim 8, wherein the resistor has punched edges at its side edges lying parallel to the direction of current flow, which edges originate from a punching out of a composite material strip.

10. A resistor according to claim 8, wherein the conductor material is copper or a copper alloy, and the conductor material has a lower specific resistance than the resistor material, and the resistor material is a resistance alloy.

11. A resistor according to claim 8, wherein the resistor was produced by the manufacturing method according to claim 1.

12. A manufacturing plant for producing an electrical resistor comprising a material feed for feeding a plate-shaped base part for the resistor, the base part having a certain thickness and corresponding to the thickness a certain value of a thickness-dependent electrical component characteristic, and a rolling station for rolling the plate-shaped base part with a certain degree of rolling, wherein the thickness of the base part is reduced in accordance with the degree of rolling; a measuring station for measuring the electrical component characteristic on the rolled output part; and an adaptation device for adapting the degree of rolling as a function of the measured electrical component characteristic.

13. A manufacturing plant according to claim 12, further comprising a welding station for welding together several material strips along their longitudinal edges to form a composite material strip which serves as the base part.

14. A manufacturing plant according to claim 13, further comprising a separating station for separating the individual resistors from the rolled base part, in particular in the form of a punching station for punching out the individual resistor elements from the base part.

15. A manufacturing plant according to claim 14, further comprising conveying means for conveying the base part through the rolling station, the measuring station and/or the separating station.

16. Method for manufacturing according to claim 1, wherein the thickness-dependent electrical component characteristic is an electrical resistance of the base part.

17. Method of manufacturing according to claim 1, wherein the adapting of the degree of rolling is made in the context of a closed-loop control system with the electrical component characteristic as a controlled variable and the degree of rolling as a control variable.

18. Method for manufacturing according to claim 4, wherein the composite material strip is stretched by rolling in the longitudinal direction of the strip with a relative elongation which is at least 20%.

19. Method for manufacturing according to claim 4, wherein the composite material strip is a bi-band consisting of two material strips joined together along their longitudinal edges, one material strip consisting of a conductor material while the other material strip consists of a resistor material.

20. Method for manufacturing, according to claim 3, wherein the base part is a resistance foil which consists of a resistor material.

21. A resistor according to claim 10, wherein the resistor material is selected from a group consisting of: a copper-manganese alloy; a chromium-nickel alloy; a copper-nickel alloy; and a copper-chromium alloy.

22. A resistor according to claim 7, wherein the welds are electron beam welds.

23. A resistor according to claim 8, wherein the resistor material has a resistivity with a temperature coefficient of less than 5-10.sup.4 K.sup.1; the resistor has an electrical resistance value of less than 1; the conductor material has a specific electrical resistance which is less than 10.sup.5 m; and the resistor material has a resistivity which is less than 2.Math.10.sup.4 m.

24. A resistor according to claim 8, wherein the connecting parts and the resistive element are flat.

25. A resistor according to claim 8, wherein the connecting parts and the resistive element are bent.

26. A resistor according to claim 8, wherein the resistor on its rolled surfaces has a low surface roughness with a roughness Rz<10 m.

Description

[0053] Other advantageous modifications the invention are characterised in the dependent claims or explained in more detail below together with the description of the preferred embodiment of the invention referring to the figures showing:

[0054] FIG. 1 a schematic representation of a manufacturing plant according to the invention for the manufacture of low-resistance current measuring resistors,

[0055] FIG. 2 the manufacturing method according to the invention in the form of a flowchart, and

[0056] FIG. 3 a perspective view of an current measuring resistor according to the invention.

[0057] FIG. 1 shows a schematic representation of an manufacturing plant according to the invention for the manufacture of low-resistance current measuring resistors 1, as they are already known in a similar form from EP 0 605 800 A1. The current measuring resistors 1 consist of two plate-shaped connecting parts 2, 3 made of copper or another conductor material and a resistor element 4 made of a resistor material, such as Manganin. The resistor element 4 is arranged in the direction of current flow between the two connecting parts 2, 3, whereby the connecting parts 2, 3 serve to introduce an electrical current to be measured into the current measuring resistor 1 or to discharge it from the current measuring resistor.

[0058] To produce the current measuring resistor 1, two copper strips 6, 7 and a resistor strip 8 are fed to a welding station 5, which are then welded together in the welding station 5 along their longitudinal edges to form a composite material strip 9, which in itself is known for example from EP 0 605 800 A1.

[0059] The composite material strip 9 is then fed to a rolling station 10, whereby the rolling station 10 rolls the composite material strip 9 with an adjustable degree of rolling AG. Rolling the composite material strip 9 in the rolling station 10 leads to a corresponding thickness reduction of the composite material strip 9, which leads to a change in cross-section and thus also to a change in the resistance R across the longitudinal direction of the strip.

[0060] The rolled composite strip 9 is then fed to a measuring station 11, which measures the electrical resistance R of the composite strip 9 transversely to the longitudinal direction of the strip and passes it on to a closed-loop controller 12. The controller 12 then continuously controls the degree of rolling AG as a function of the measured resistance R in order to adjust the measured resistance R to a predetermined set value.

[0061] The composite material strip 9 is then finally fed to a punching station 13, in which the individual current measuring resistors 1 are separated from the composite material strip 9.

[0062] The controlled rolling down of the composite material strip 9 means that the resistance value of the individual current measuring resistors 1 corresponds extremely exactly to a specified set value, so that the otherwise necessary adjustment incisions can be dispensed with.

[0063] FIG. 2 shows the manufacturing method according to the invention in the form of a flow chart.

[0064] In a first step S1, the two copper strips 6, 7 are first welded together with the resistor strip 8 to form the composite material strip 9.

[0065] In a second step S2 the composite material strip 9 is then rolled with the specified degree of rolling AG.

[0066] In the next step S3, the resistance R of the rolled composite strip 9 is measured transversely to the longitudinal direction of the strip.

[0067] In a further step S4, the degree of rolling AG is then adjusted as a function of the measured resistance R.

[0068] The method steps S1-S4 are continuously repated within the framework of the manufacturing method according to the invention.

[0069] The invention is not limited to the preferred embodiment described above. Rather, a large number of variants and modifications are possible, which also make use of the idea of invention and therefore fall within the scope of protection. In particular, the invention also claims protection for the object and the characteristics of the dependent claims irrespective of the claims referred to in each case and in particular also without the characterising features of the main claim.

LIST OF REFERENCE SIGNS

[0070] 1 Current measuring resistor [0071] 2 Connecting part [0072] 3 Connecting part [0073] 4 Resistor element [0074] 5 Welding station [0075] 6 Copper strip [0076] 7 Copper strip [0077] 8 Resistor strip [0078] 9 Composite material strip [0079] 10 Rolling station [0080] 11 Measuring station [0081] 12 Closed-loop Controllers [0082] 13 Punching station [0083] AG Degree of rolling [0084] R Resistance of the composite strip transversely to the longitudinal direction of the strip