System and method for detecting a torsional load acting on a torque-transmitting component

Abstract

The present invention relates to a system (100) for detecting a torsional load (T) acting on a torque-transmitting component (110), comprising a component (110) having a section (120) made of magnetizable material in which at least two magnetic strips (121, 123, 125) extending in the circumferential direction (112) and each having opposite magnetization directions (122, 124, 126) are arranged consecutively in an axial direction (111) of the component (110), a first sensor unit (2) having two sensors (20, 22) associated with a first magnetic strip (123) for detecting a radial field component (6), and a second sensor unit (3) having two sensors (30, 32) associated with a second magnetic strip (121, 125) for detecting a radial field component (6); the invention also relates to a corresponding method.

Description

[0001] System and method for detecting a torsional load acting on a torque-transmitting component

[0002] Technical field

[0003] The present invention relates to a system and a method for detecting a torsional load acting on a torque-transmitting component. The system or the method can be used, for example, to determine the torque on shafts.

[0004] State of the art

[0005] Non-contact magnetic field sensors are used in a variety of applications for monitoring rotating components, for example Hall sensors for torque measurement.

[0006] Furthermore, there are devices commonly referred to as "magnetoelastic sensor devices". These utilize fundamental mechanical and magnetic properties of a magnetized material to measure changes in magnetic fields emitted by the component being diagnosed.

[0007] Investigations have shown that mechanical loads on a component change the shape and orientation of magnetic fields emitted by magnetized material, for example in the case of a torsional load on a shaft intended for torque transmission.

[0008] The component material can be magnetized directly. Alternatively, one or more additional elements, such as a ring body with magnetized material, can be applied to the component.

[0009] To determine the torque, or synonymously the torsion or torsional load, it is known to arrange a sensor-equipped sensor array on a region of magnetized material of the component, comprising one or more circumferentially oriented bands. The production of the magnetic tracks, or synonymously magnetic bands, on a component with magnetizable material using magnets is known per se and can be found, for example, in US 6,581,480 B1 or US 8,087,304 B2.

[0010] The "circumferential orientation" of the magnetic tapes means that, in a torsionally unloaded state of the component, the magnetization directions of the magnetic tapes are essentially oriented circumferentially. If a torsional load occurs on the component, the magnetic fields of the magnetic tapes change, manifesting themselves outside the magnetized component. The resulting magnetization directions of the magnetic tapes then exhibit a radial component and an axial field component, the magnitude or change in magnitude of which is proportional to the magnitude of the torsional stress present in the component, i.e., the torque applied to the component about its longitudinal axis. It has been found that the changes in the magnetic fields are proportional to the mechanical load acting on the component, and are linear and repeatable, at least within the elastic limit of the material.

[0011] Axial-measuring sensors, synonymous with "axial sensors" or "axially sensitive sensors," are known that can detect these axial field components of the magnetic field, for example, axially oriented coils. Since the coils are aligned in the axial direction, they can only detect axially oriented magnetic field components; rather, a measurable signal is only generated in the coils by the presence of an axial magnetic field component. For example, DE 10 2015 102 337 A1 discloses a system with axial sensors.

[0012] Furthermore, radially measuring sensors, synonymous with "radial sensors" or "radially sensitive sensors," which can detect these radial field components of the magnetic field, are known, for example, sensors comprising a Hall sensor. Since radial sensors are sensitive in the radial direction, they can only detect magnetic field components oriented in the radial direction; rather, a measurable signal is only generated by the presence of a radial magnetic field component. For example, US 2024 / 0060838 A1 discloses a system with radial sensors.

[0013] Furthermore, multi-axis sensitive sensors are known, for example TMR sensors, as can be seen in DE 10 2020 203 914 A1.

[0014] The amplitude of the radial and axial field components generated by a given torsional load is not constant across the width of a magnetic tape when viewed in the axial direction of the component. Instead, the amplitude or density of the axial magnetic field component of a magnetic tape exhibits a curved or parabolic profile, with the maximum amplitude of the axial magnetic field located in the center of the magnetic tape and decreasing symmetrically towards the axial ends of the tape, as can be seen, for example, in US 8,087,304 B2 (Figs. 9, 10). With multiple magnetic tapes arranged axially in series, this results in a substantially sinusoidal profile of the magnetic field emitted by the tapes. The shorter the width of the magnetic tapes, the more pronounced the sinusoidal shape, and thus the shorter or less pronounced any plateau at the local maximum.In order to obtain maximum axial sensitivity and thus of the sensors, the coils are always positioned centrally in the prior art with respect to the magnetic field width in the axial direction of the component, since the center of the coil is thus positioned centrally to the local maximum of the axial magnetic field caused by torsional loading.

[0015] The magnitude or density of the radial magnetic field component of a magnetic tape also exhibits a curved profile. At one axial end of the tape, it has a first extremum, for example, a minimum (-5 G), and at the other axial end, a second extremum with the opposite sign (a maximum, for example, +5 G). Between these extrema, the profile is essentially linear, with the zero point located approximately at the axial center of the tape. The magnitude of the radial magnetic field component decreases progressively from the ends outwards. The profile of the radial magnetic field component can be described as similar to the graph of the function f(x) = k - x ■ e~ |X| be viewed.

[0016] With multiple magnetic tapes arranged one behind the other in the axial direction, the resulting magnetic field pattern is as described in Figure 2 of this document. To achieve maximum sensitivity of the radial sensors, in the prior art they are positioned at or near the end of a magnetic tape when viewed axially from the component.

[0017] The magnitudes of the extreme points of the radial field component are each greater than the magnitude of the maximum of the axial field component. Therefore, when measuring the radial field component, "more signal" is available.

[0018] Description of the invention Starting from the known prior art, it is an object of the present invention to provide an improved system for detecting a torsional load acting on a torque-transmitting component, as well as a corresponding method.

[0019] The problem is solved by a system for detecting a torsional load acting on a torque-transmitting component, comprising the features of claim 1. Advantageous embodiments are described in the dependent claims, the description, and the figures.

[0020] Accordingly, a system for detecting a torsional load acting on a torque-transmitting component is proposed, comprising a component with a section made of magnetizable material in which at least two circumferentially extending magnetic strips are arranged successively in an axial direction of the component, wherein adjacent magnetic strips each have opposite magnetization directions, further comprising a first sensor unit with two sensors arranged at a predetermined distance from each other in the axial direction, which are assigned to a first magnetic strip, are configured to detect a radial field component of the assigned magnetic strip and form a first channel, and further comprising a second sensor unit with two sensors arranged at a predetermined distance from each other in the axial direction, which are assigned to a second magnetic strip adjacent to the first magnetic strip.are designed to detect a radial field component of the associated magnetic tape and form a second channel separate from the first channel.

[0021] By providing the first and second sensor units and their independently available signal channels, a particularly precise determination of the torque can be achieved. Furthermore, the presence of external fields can be inferred, for example, by comparing the signals of the two channels or the calculated torques of the two channels, such as by relating them.

[0022] The sensors of a sensor unit form the channel, such that the differential is formed from a signal of the first sensor and a signal of the second sensor. In other words, the signal S of the sensor unit's channel is the difference between the signals S1 and S2 of the two sensors in the sensor unit, i.e., S = S1 - S2, or, if this is advantageous for further evaluation, S = S2 - S1. Optionally, the magnitude of the signal S, i.e., |S|, can be used as the output signal. The first sensor unit and the second sensor unit each provide information independent of the other. The sensor units measure their own signals separately and independently of each other.According to one embodiment, the component can comprise, in its section made of magnetizable material, three circumferentially extending magnetic strips arranged sequentially in the axial direction, with adjacent magnetic strips having opposite magnetization directions. The sensors of the first sensor unit can be assigned to the middle magnetic strip of the three magnetic strips, and the sensors of the second sensor unit can be assigned to one of the two outer magnetic strips of the three magnetic strips.

[0023] Advantageously, exactly three adjacent magnetic strips can be provided. In this configuration, the magnitudes of the extrema of the radial field component under torsional load (synonymous with torque transmission) at the boundaries or ends of the middle strip are higher than the magnitudes of the extrema of the radial field component at the outer ends of the two outer magnetic strips opposite the middle strip. Accordingly, the magnitudes of the differential signals from the sensors of the first sensor unit and the differential signals from the sensors of the second sensor unit can be different when the component is subjected to a specific torque. The signal profiles of the two sensor units, considered as a function of the torque, can therefore exhibit different slopes. This allows for a particularly accurate determination of the torsional load in the section of magnetized material.Furthermore, comparing the two values ​​allows for a particularly good conclusion to be drawn about the presence of an external field that is not caused by the torsional load in the component.

[0024] More than three magnetic tapes can also be provided, for example, four or five. Of these, three adjacent magnetic tapes form the aforementioned three magnetic tapes. Advantageously, the second sensor unit is attached to the outermost magnetic tape, and the first sensor unit is attached to the magnetic tape next to the outermost magnetic tape. However, the system is not limited to such embodiments.

[0025] According to one embodiment, each sensor unit can have one sensor assigned to a first end of the associated magnetic tape and the other sensor assigned to the other end of the associated magnetic tape. With respect to the axial direction, each sensor can either be positioned directly at the end or offset by a predetermined axial offset relative to its assigned end in the direction of the axial center of the associated magnetic tape. If the positioning with a predetermined offset is chosen, the system can compensate for axial play between the component and the sensor units. Although the magnitude of the delivered signal value of the channel decreases, i.e., the channel amplitude, the signal magnitude of the channel remains approximately the same even if the component is displaced axially relative to the component. Furthermore, the positioning with a predetermined offset allows for the possibility that the sensors located at the same end of the middle tape, or at the same end of the magnetic tape, may be positioned differently.The sensors of the two sensor units, which are assigned to the boundary between the middle band and the outer band, can be arranged consecutively in the axial direction and without offset in the circumferential direction and / or in the radial direction to each other.

[0026] According to one embodiment, the specified offset can be less than or equal to 0.25 times the width in the axial direction of the associated magnetic tape, optionally less than or equal to 0.2, less than or equal to 0.15, or less than or equal to 0.10 times the width. Alternatively or additionally, the specified offset can optionally be greater than or equal to 0.025, optionally greater than or equal to 0.05, 0.075, or optionally greater than or equal to 0.1 times the width in the axial direction of the associated magnetic tape.

[0027] If a sensor is positioned directly at the end of a magnetic tape, it generates a signal with the maximum possible amplitude. If a sensor is positioned at a predetermined offset from the end, its signal is somewhat smaller than that of a sensor without a distance, but the effects of mounting misalignment or operational misalignment, for example, due to design-related axial play in the component's bearing, are reduced. The signal strength of the channel remains approximately constant when the component is displaced axially in a sensor unit with sensors positioned at the ends.

[0028] In this document, the reference point for each sensor is its axial sensor center. The sensor center of each sensor and the axial center of its respective end of the magnetic tape are therefore axially separated by the specified distance. The foregoing refers to a planned installation position of the sensor unit and the component, at least in the axial direction—that is, a planned position of the sensors of the sensor units relative to the component, and more specifically, relative to its magnetic tapes. The axial distance between the two sensors of a sensor unit is accordingly calculated as the difference between the width of the associated magnetic tape and the sum of the aforementioned axial offsets of the two sensors. The sum of the two axial offsets is therefore to be subtracted from the axial width of the associated magnetic tape. Similarly, in this document, the reference point for each sensor is its radial sensor center and its circumferential center.

[0029] The specified offset can be the same for each sensor and / or for both sensor units. Alternatively, the sensors can be arranged at different distances from the respective ends of their assigned magnetic strip. By offsetting the sensors as described above, the sensitivity of the sensor unit decreases slightly, but at the same time, the signal behavior of the sensor unit is more stable with respect to axial displacement of the sensor unit, or more precisely, of its sensors, relative to the component. Furthermore, the influence of external magnetic fields can be reduced due to the shorter distance between the two sensors.

[0030] According to one embodiment, the specified offset can be greater than or equal to a maximum axial play offset expected from a specified installation position of the sensor units relative to the component.

[0031] According to one embodiment, the sensors can be arranged radially inside or outside their respective associated magnetic strips.

[0032] According to one embodiment, each sensor of at least one of the sensor units can be arranged on its own carrier.

[0033] Alternatively or additionally, the two sensors of at least one of the sensor units can be arranged on a common carrier. For example, the sensors of the first sensor unit can be arranged on a common carrier, and the sensors of the second sensor unit can be arranged on a common carrier.

[0034] Alternatively, the sensors of the first and second sensor units can be arranged on a common carrier.

[0035] According to one embodiment, the sensors of the first sensor unit can be arranged at the same height when viewed circumferentially, and / or the sensors of the second sensor unit can be arranged at the same height when viewed circumferentially.

[0036] Optionally, the sensors of both sensor units are arranged at the same height in the circumferential direction.

[0037] In this document, "at the same level circumferentially" means that there is no offset in the circumferential direction. This does not necessarily preclude the possibility that the parts arranged "at the same level circumferentially" may have an offset in the axial or radial direction with respect to the central longitudinal axis of the component and / or a surface of the associated magnetic tape. Similarly, "with an offset circumferentially" means that there is a gap in the circumferential direction. According to one embodiment, an evaluation device may also be provided, which may be configured to acquire and / or evaluate the signals of the first channel and the signals of the second channel. The evaluation device may optionally be configured to convert the signals of the channels into a torque.The evaluation device can optionally be configured to compare the detected signals of the first and second channels and / or the torques calculated from them, optionally to relate them, for example to detect the presence of an external field.

[0038] The problem is further solved by a system for detecting a torsional load acting on a torque-transmitting component, comprising the features of claim 4. Advantageous embodiments are described in the dependent claims, the description, and the figures.

[0039] Accordingly, a system for detecting a torsional load acting on a torque-transmitting component is proposed, comprising a component with a section of magnetizable material in which a circumferentially extending magnetic tape with circumferentially oriented magnetization direction is arranged, a first sensor unit with two sensors arranged at a predetermined distance from each other in the axial direction, which are assigned to the magnetic tape, are configured to detect a radial field component of the magnetic tape and form a first channel, and a second sensor unit with two sensors arranged at a predetermined distance from each other in the axial direction, which are assigned to an area adjacent to the magnetic tape, are configured to detect a radial field component of a magnetic field emitted by the component and form a second channel K2 separate from the first channel K1.

[0040] The system achieves the advantages and effects described above in an analogous manner. In fact, the two systems differ only in that the sensors of the second sensor unit are not located on a magnetic tape adjacent to that of the first sensor unit, but rather in an area adjacent to that of the first sensor unit on which no magnetic tape has been applied. Due to the magnetization of the magnetic tape associated with the first sensor unit, this adjacent area also exhibits a certain degree of magnetization, although it is less pronounced than that of a magnetic tape. The only difference, therefore, is that the amplitude of the signal of the second channel K2 is smaller in this implementation of the system than in a channel K2 whose sensors are associated with a magnetic tape.According to one embodiment, one sensor of the first sensor unit is assigned to a first end of the magnetic tape, and the other sensor of the first sensor unit is assigned to the other end of the magnetic tape. A sensor of the second sensor unit is assigned to a first end of the magnetic tape, and the other sensor of the second sensor unit is positioned a predetermined distance further from the magnetic tape than the sensor of the second sensor unit assigned to the end of the magnetic tape. With respect to the axial direction, the sensors of the first sensor unit can either be positioned directly at the assigned end or offset by a predetermined axial offset in the direction of the assigned end towards the axial center of the magnetic tape.Furthermore, the sensor of the second sensor unit assigned to the end can either be positioned directly at the end or offset by a predetermined axial offset in the axial direction to the assigned end in the direction away from the magnetic tape.

[0041] According to one embodiment, the specified axial offset can be less than or equal to 0.25 times the width in the axial direction of the magnetic tape, optionally less than or equal to 0.2, less than or equal to 0.15, less than or equal to 0.10 times the width, and / or the specified axial offset can optionally be greater than or equal to 0.025, 0.05, 0.075 or 0.1 times the width in the axial direction 111 of the magnetic tape.

[0042] According to one embodiment, the specified offset can be greater than or equal to a maximum axial play offset expected from a specified installation position of the sensor units relative to the component.

[0043] According to one embodiment, the sensors can be arranged radially inside or outside the respective associated magnetic tape and / or radially inside or outside the surface of the component.

[0044] According to one embodiment, each sensor of at least one of the sensor units can be arranged on its own carrier.

[0045] Alternatively or additionally, the two sensors of at least one of the sensor units can be arranged on a common carrier. For example, the sensors of the first sensor unit can be arranged on a common carrier, and the sensors of the second sensor unit can be arranged on a common carrier.

[0046] Alternatively, the sensors of the first and second sensor units can be arranged on a common support. According to one embodiment, the sensors of the first sensor unit can be arranged at the same height when viewed circumferentially, and / or the sensors of the second sensor unit can be arranged at the same height when viewed circumferentially.

[0047] Optionally, the sensors of both sensor units are arranged at the same height in the circumferential direction.

[0048] According to one embodiment, an evaluation device may also be provided, which may be configured to acquire and / or evaluate the signals of the first channel and the signals of the second channel. The evaluation device may optionally be configured to convert the signals of the channels into torque values. The evaluation device may optionally be configured to compare the acquired signals of the first and second channels and / or the torques calculated therefrom, optionally relating them, for example, to detect the presence of an external field.

[0049] The problem stated above is further solved by a method for detecting a torsional load acting on a torque-transmitting component, comprising the features of claim 12. Advantageous embodiments of the method are described in the dependent claims, the present description, and the figures.

[0050] Accordingly, a method for detecting a torsional load acting on a torque-transmitting component is proposed, comprising providing a component with a section of magnetizable material in which at least two circumferentially extending magnetic strips are arranged successively in an axial direction of the component, wherein adjacent magnetic strips each have opposite magnetization directions, further comprising providing a first sensor unit with two sensors arranged at a predetermined distance from each other in the axial direction, which are assigned to a first magnetic strip, are configured to detect a radial field component of the assigned magnetic strip and form a first channel K1, and further comprising providing a second sensor unit with two sensors arranged at a predetermined distance from each other in the axial direction.which are assigned to a second magnetic tape adjacent to the first magnetic tape, are configured to detect a radial field component of the assigned magnetic tape and form a second channel K2 separate from the first channel. The advantages and effects described with regard to the system can be achieved by this method as well. Accordingly, a repeated description of these is omitted to avoid redundancy. Instead, reference is made to the foregoing. What is written in this document regarding the system also applies to the method and vice versa.

[0051] According to one embodiment, the component can comprise, in its section made of magnetizable material, three, optionally exactly three, circumferentially extending magnetic strips which are arranged successively in the axial direction, wherein adjacent magnetic strips each have opposite magnetization directions to each other, wherein the sensors of the first sensor unit are assigned to the middle magnetic strip of the three magnetic strips and the sensors of the second sensor unit are assigned to one of the two outer magnetic strips of the three magnetic strips.

[0052] According to one embodiment, the method may further include acquiring the signals of the first channel and the signals of the second channel and / or evaluating the signals of the first channel and the signals of the second channel.

[0053] According to one embodiment, the signals from the channels can each be converted into a torque.

[0054] According to one embodiment, the detected signals or the calculated torques of the first and second channels can be compared, optionally related, for example to detect the presence of an external field.

[0055] The problem stated above is further solved by a method for detecting a torsional load acting on a torque-transmitting component, comprising the features of claim 14. Advantageous embodiments of the method are described in the dependent claims, the present description, and the figures.

[0056] Accordingly, a method for detecting a torsional load acting on a torque-transmitting component is defined, comprising providing a component with a section of magnetizable material in which a circumferentially extending magnetic tape with circumferentially oriented magnetization direction is arranged, and providing a first sensor unit with two sensors arranged at a predetermined distance from each other in the axial direction, which are assigned to the magnetic tape, are configured to detect a radial field component of the magnetic tape and form a first channel, and providing a second sensor unit with two sensors arranged at a predetermined distance from each other in the axial direction, which are assigned to an area adjacent to the magnetic tape.are designed to detect a radial field component of a magnetic field emitted by the component and form a second channel K2 that is separate from the first channel K1.

[0057] The advantages and effects described in relation to the previously described method and system can be achieved through this method as well. Therefore, a repeated description of these is omitted to avoid redundancy. Instead, reference is made to the foregoing. This also applies to this method. In fact, the two proposed methods differ only in that the sensors of the second sensor unit are not assigned to a magnetic tape adjacent to the magnetic tape of the first sensor unit, but rather to an area adjacent to the magnetic tape of the first sensor unit on which no magnetic tape has been applied. Due to the magnetization of the magnetic tape assigned to the first sensor unit, this adjacent area also exhibits a certain degree of magnetization, although this is less pronounced than that of a magnetic tape.The only difference is therefore that the amplitude of the signal of the second channel K2 is smaller in this implementation of the method than in a channel K2 when its sensors are assigned to a magnetic tape.

[0058] According to one embodiment, the method may further include acquiring the signals of the first channel and the signals of the second channel and / or evaluating the signals of the first channel and the signals of the second channel.

[0059] According to one embodiment, the signals from the channels can each be converted into a torque.

[0060] According to one embodiment, the detected signals or the calculated torques of the first and second channels can be compared, optionally related, for example to detect the presence of an external field.

[0061] Brief description of the characters

[0062] Preferred further embodiments of the invention are explained in more detail by the following description of the figures. These show:

[0063] Figure 1 schematically shows a view of a system for detecting a torsional load acting on a component during torque transmission through the component; Figure 2 schematically shows the course of a radial field component resulting in the axial direction over three magnetic strips in the system from Figure 1;

[0064] Figure 3 schematically shows the signal waveform of a first channel and a second channel of the system from Figures 1 and 2;

[0065] Figure 4 schematically shows the signal path of a first channel and a second channel of a system according to a further embodiment;

[0066] Figure 5 schematically illustrates a method for detecting a torsional load acting on a torque-transmitting component;

[0067] Figure 6 schematically shows a sensor arrangement for detecting a torsional load acting on a torque-transmitting component, as it can be used in the system according to Figure 1;

[0068] Figure 7 schematically shows another sensor arrangement for detecting a torsional load acting on a torque-transmitting component, as can be used in the system according to Figure 1;

[0069] Figure 8 schematically shows another sensor arrangement for detecting a torsional load acting on a torque-transmitting component, as can be used in the system according to Figure 1;

[0070] Figure 9 schematically shows a sensor arrangement of the system according to Figure 1;

[0071] Figure 10 schematically shows a further system for detecting a torsional load acting on a component during torque transmission through the component;

[0072] Figure 11 schematically shows a further system for detecting a torsional load acting on a component during torque transmission through the component; and

[0073] Figure 12 schematically shows the course of a radial field component resulting in the axial direction over component 1 10 in the system from Figure 11.

[0074] Detailed description of preferred embodiments. Preferred embodiments are described below with reference to the figures. Identical, similar, or equivalent elements in the different figures are designated with identical reference numerals, and repeated descriptions of these elements are sometimes omitted to avoid redundancy.

[0075] Figure 1 schematically shows a side view of a system 100 for detecting a torsional load acting on a torque-transmitting component 110. The system 100 comprises a component 110 with a section 120 made of magnetizable material in which three magnetic strips 121, 123, 125, extending circumferentially 112 of the component 110, are arranged successively in an axial direction 111 of the component 110, each with a predetermined width 127, wherein adjacent magnetic strips 121, 123, 125 each have opposite magnetization directions 122, 124, 126.

[0076] According to this embodiment, the magnetic tapes 121, 123, 125 are optionally arranged directly adjacent to one another, i.e., without any axial spacing 111 between two successive magnetic tapes 121, 123, 125. The ends 27 of the outer magnetic tapes 121, 125 facing the middle magnetic tape 123 thus coincide with the ends 27 of the middle magnetic tape 123.

[0077] Alternatively, according to another embodiment (not shown), the ends 27 of the magnetic tapes 121, 123, 125 can optionally be arranged axially spaced apart from each other, i.e. with a predetermined distance between two successive magnetic tapes 121, 123, 125.

[0078] System 100 further comprises a first sensor unit 2 with two sensors 20, 22 arranged at a predetermined distance 21 in the axial direction 11 1 from each other, which are assigned to the central magnetic tape 123. The sensors 20, 22 are configured to detect a radial field component of the assigned magnetic tape 123 and form a first channel K1.

[0079] System 100 further comprises a second sensor unit 3 with two sensors 30, 32 arranged at a predetermined distance 31 in the axial direction 111 from each other, which are assigned to one of the two outer magnetic tapes 121, 125, here magnetic tape 121. The sensors 30, 32 are configured to detect a radial field component of the assigned magnetic tape 121 and form a second channel K2 separate from the first channel K1.

[0080] The sensor units 2, 3 can be understood together as a sensor arrangement 7. For each sensor unit 2, 3, one sensor 20, 30 is assigned to a first end 27 and the other sensor 22, 32 to the other end 27 of the associated magnetic tape 121, 123.

[0081] According to this embodiment, the sensors 20, 22, 30, 32 are each positioned offset by a predetermined axial offset 28 in the axial direction 111 relative to the associated end 27 in the direction of the axial center of the associated magnetic tape 121, 123. The predetermined distance 21, 31 of the sensors 20, 22, 30, 32 of a sensor unit 2, 3 thus corresponds to the width 127 of the associated magnetic tape 121, 123 minus the two offsets 28 of the sensors 20, 22 and 30, 32 of the sensor unit 2 and 3, respectively.

[0082] The specified axial offset 28 is optionally 0.1 times the width 127 of the associated magnetic tape 121, 123. Since the width 127 of the magnetic tapes 121, 123, 125 is 10 mm in this non-restrictive embodiment, the specified offset 28 of all sensors 20, 22, 30, 32 to their respective associated end 27 is 1 mm each. The sensors 20, 22, 30, 32 do not necessarily have to have the same offset 28, but can be spaced at different distances from the associated end 27.

[0083] The sensor 20 of the first sensor unit 2, which faces the second sensor unit 3 and is therefore located closer to the latter than the other sensor 22 of the first sensor unit 2, and the sensor 32 of the second sensor unit 3, which faces the first sensor unit 2 and is therefore located closer to the latter than the other sensor 30 of the second sensor unit 3, thus have an axial distance 4 to each other, which according to this optional embodiment consists of the sum of the offset 28 of the sensor 20 to the associated end 27 and the offset 28 of the sensor 32 to the associated end 27, i.e. twice the offset 28.

[0084] The sensors 20, 22, 30, 32 are optionally arranged radially outside their respective assigned magnetic bands 121, 123.

[0085] They are also arranged on an optional common support (see Figure 9), which is not shown here.

[0086] The sensors 20, 22 of the first sensor unit 2 are arranged at the same height when viewed in the circumferential direction 1 12. Likewise, the sensors 30, 32 of the second sensor unit 3 are arranged at the same height when viewed in the circumferential direction 112. They are located at the same radial distance 9 from the surface of the section 120. The sensors 20, 22, 30, 32 are therefore only spaced apart from each other in the axial direction 111. Optionally, the sensors 20, 22, 30, 32 of both sensor units 2, 3 are arranged at the same height in the circumferential direction 112. However, they can also be arranged with an offset from each other in the circumferential direction 112 with respect to the longitudinal axis 111.

[0087] System 100 optionally includes an evaluation device 5 configured to acquire and evaluate the signals of the first channel K1 and the signals of the second channel K2, wherein the evaluation device 5 is optionally configured to convert the signals of channels K1 and K2 into a torque "T" (in Nm), wherein the evaluation device 5 is optionally configured to compare the acquired signals of the first and second channels K1 and K2 and / or the torques T calculated therefrom, optionally to relate them. By comparing the values, the presence of an external field can be inferred.

[0088] Figure 2 schematically shows the shape of the radial field component 6 of the magnetic field emitted by the magnetic tapes 121, 123, 125 resulting from a torsional load of a certain height in the component 110 via the component 110, i.e. via the magnetic tapes 121, 123, 125 and beyond along the axial direction 111 (referred to as longitudinal direction L) in a Cartesian coordinate system.

[0089] It can be seen that the course of the radial field component 6 is not the same for all three magnetic tapes 121, 123, 125. For the middle magnetic tape 123, the course extends essentially between a maximum 62 and a minimum 63, with these extrema coinciding approximately with the boundaries or ends 27 of the middle magnetic tape 123.

[0090] Since there is no further magnetic tape on the side of the outer magnetic tapes 121, 125 facing away from the middle magnetic tape 123, the shape of the curve is flatter compared to the middle magnetic tape 123. Furthermore, the other extrema 61, 64 of the radial field component 6 lie outside the outer magnetic tapes 121, 125 at a distance from the outer ends 27. Such a shape of the radial field component 6 can be achieved in particular if the magnetic tapes 121, 123, 125 were produced via magnets in the section 120 of magnetizable material, as described, for example, in WO 99 / 56099 A1 relating to Figure 4a, the contents of which are incorporated into this document by reference.

[0091] For better understanding, the sensors 20, 22, 30, 32 are indicated in Figure 2 at their positions with the offset 28 to their respective associated end 27. The sensors 20, 22 and 30, 32 of each sensor unit 2 and 3 are each connected such that the signal of channel K1 and the signal of channel K2 each represent the differential D of the signal S1 of the respective first sensor 20, 30 and the signal S2 of the respective second sensor 22, 32. The signal of the first channel K1 represents the differential D1, which corresponds to the difference between the signal SI2 of the first sensor 20 of the first sensor unit 2 and the signal S22 of the second sensor 22 of the first sensor unit 2, i.e., D1 = SI2 - S22, and the signal of the second channel K2 represents the magnitude of the differential |D2| This represents the difference between the signal SI3 of the first sensor 30 of the second sensor unit 3 and the signal S2s of the second sensor 32 of the second sensor unit 3, i.e. D2 = SI3 - S2s.Alternatively, the signal of the second channel, more precisely the differential D2, can also be formed as the difference between the signal 23 of the second sensor 32 of the second sensor unit 3 and the signal SI3 of the first sensor 30 of the second sensor unit 3, i.e. D2 = S23 - SI3, for example, if this may be advantageous for further evaluation.

[0092] It can be seen that, due to the formation of the radial field component 6 described above, when viewed over the magnetic tapes 121, 123, 125, the differential D2 of the second channel K2 of the second sensor unit 3 is smaller than the differential D1 of the first channel K1 of the first sensor unit 2.

[0093] Figure 3 schematically depicts the output signals of channels K1 and K2 “U” in mV as a function of the torque applied to the component, or synonymously, the torsional load T in Nm, in a Cartesian coordinate system. Since, as described in Figure 2, the differential D1 of the signals from sensors 20, 22 of the first sensor unit 2 is greater than the differential D2 of the signals from sensors 30, 32 of the second sensor unit 3, the output signal value of the first channel K1 is greater than that of the second channel K2 for the same torsional load T. Accordingly, the slope m1 of the signal waveform of the first channel K1 is also greater than the slope m2 of the signal waveform of the second channel K2.

[0094] Figure 4 schematically shows the output signals of channels K1 and K2 “U” in mV as a function of the torque applied to the component, or synonymously, the torsional load T in Nm, in a Cartesian coordinate system for an alternative embodiment. This embodiment is similar to the embodiment described for Figure 3 and, like the embodiment for Figure 3, corresponds in its structure to Figures 1 and 2. In contrast to Figure 3, the output signals of channels K1 and K2 each have a specific offset value at 0 Nm (zero N) torsional load, i.e., in the torsional load-free state. Figure 5 schematically illustrates a method for detecting a torsional load T acting on a torque-transmitting component 10 using the system 100 from Figures 1 to 3.

[0095] First, the component 110 with the section 120 made of magnetizable material, in which the three magnetic tapes 121, 123, 125 extending in the circumferential direction 112 are arranged successively in an axial direction 111 of the component 110, wherein the adjacent magnetic tapes 121, 123, 125 each have opposite magnetization directions 122, 124, 126, is to be provided (S201 ).

[0096] On component 110, the first sensor unit 2, comprising two sensors 20, 22 arranged at a predetermined distance 21 in the axial direction 11 1 from each other, is to be arranged such that the sensors 20, 22 are assigned to the central magnetic strip 123, such that the sensors can detect the radial field component 6 of the assigned magnetic strip 123. The sensors 20, 22 are to be connected together to form the first channel K1 (S202).

[0097] Furthermore, the second sensor unit 3, comprising the two sensors 30, 32 arranged at a predetermined distance 31 in the axial direction 111 from each other and assigned to the outer magnetic tape 121, is to be provided on component 1 10 such that the sensors 30, 32 can detect the radial field component 6 of the assigned magnetic tape 121. The sensors 30, 32 are to be connected together to form the second channel K2 (S203).

[0098] Optionally, the method may further include acquiring the signal of the first channel K1 and the signal of the second channel K2, and optionally evaluating the signals of the first and second channels K1, K2, optionally converting the signals of channels K1, K2 into a torque TKI, TK2, for example by calculating the signals of channels K1, K2 with a predetermined factor k1, k2 and / or within a predetermined function f1, f2 (S204).

[0099] Furthermore, optionally, the recorded signals of the first and second channels K1 and K2 can be compared. Alternatively or additionally, the torques T calculated from the signals of channels K1 and K2 can also be compared (p. 205). The comparison can involve "setting a ratio" between the two values, for example D1 / D2 or TKI / TK2.

[0100] Optionally, the comparison can be used to determine whether an external magnetic field or an electric field is present in the area of ​​the sensor units 2, 3, which together can be understood as sensor arrangement 7 (S206). For example, the comparison value described above can be compared with predefined limit values, such as an upper limit value and a lower limit value.

[0101] Figures 6 to 8 show various embodiments of the sensor arrangement 7 described in Figures 1 and 2. The views are oriented essentially radially with respect to the central longitudinal axis 111 of the component 110. The sensor arrangements 7 shown are merely exemplary embodiments. The sensor arrangement 7 is not limited to these embodiments.

[0102] Figure 6 schematically shows a view of a sensor arrangement 7 with a first sensor unit 2 and a second sensor unit 3. The sensors 20, 22 of the first sensor unit 2 are arranged at the same height when viewed in the circumferential direction 112. Likewise, the sensors 30, 32 of the second sensor unit 3 are arranged at the same height when viewed in the circumferential direction 112. Here, the sensors 20, 22 of the first sensor unit 2 are arranged with an offset 29 in the circumferential direction 112 relative to the sensors 30, 32 of the second sensor unit 3. Furthermore, the sensors 20, 22, 30, 32 are positioned such that, when viewed in the axial direction 111, they are located directly at the boundaries or ends 27 of the associated magnetic strips 121, 123. Thus, unlike the embodiment in Figure 1, the sensors 20, 22, 30, 32 do not have an axial offset 28, but are arranged relative to each other in such a way that they can be positioned directly on the ends 27.The distance 21, 31 of the sensors 20, 22 and 30, 32 of a sensor unit 2, 3 therefore corresponds to the width 127 of the respective assigned magnetic tape 121, 123.

[0103] In this embodiment, each sensor 20, 22, 30, 32 is optionally arranged on its own carrier 8.

[0104] Figure 7 schematically shows a further embodiment of a sensor arrangement 7. This corresponds essentially to that shown in Figure 6. However, the sensors 20, 22 of the first sensor unit 2 are arranged on a common carrier 8. Likewise, the sensors 30, 32 of the second sensor unit 3 are arranged on their own common carrier 8.

[0105] They are also arranged on an optional common support (see Figure 9), which is not shown here.

[0106] Figure 8 schematically shows a further embodiment of a sensor arrangement 7. This corresponds essentially to that shown in Figure 1. Optionally, the sensors 20, 22, 30, 32 of both sensor units 2, 3 are arranged at the same height in the circumferential direction 112. As in the embodiment according to Figure 7, the sensors 20, 22 of the first sensor unit 2 are arranged on their own common support 8, and likewise the sensors 30, 32 of the second sensor unit 3 are arranged on their own common support 8.

[0107] Figure 9 schematically shows a further embodiment of a sensor arrangement 7. This corresponds essentially to that shown in Figure 1. Optionally, the sensors 20, 22, 30, 32 of both sensor units 2, 3 are arranged at the same height in the circumferential direction 112. In addition, the sensors 20, 22, 30, 32 of the first and the second sensor units 2, 3 are arranged on a common support 8.

[0108] Figure 10 schematically shows another embodiment of a system that essentially corresponds to that of Figure 1, wherein each sensor unit 2, 3 has, in addition to the two sensors 20, 22, 30, 32 described in Figure 1, two further sensors 20', 22', 30', 32' which are offset by 180° in the circumferential direction, i.e., are arranged analogously to the sensors 20, 22, 30, 32 relative to the sensors 20, 22, 30, 32.

[0109] Sensors 20, 22, 20', 22' can be connected to a common channel K1, and sensors 30, 32, 30', 32' can be connected to a common channel K2. Alternatively, the additional sensors 20', 22' can be connected as a further first sensor unit and third sensor unit 2', respectively, and form their own channel K3, which provides information independent of the other channels. Similarly, sensors 30', 32' can be connected as a further second sensor unit and fourth sensor unit 2', respectively, and form their own channel K4, which provides information independent of the other channels.

[0110] Figure 11 shows a further embodiment of a system 200 for detecting a torsional load T acting on a torque-transmitting component 110. Its sensor arrangement 7 is essentially identical to the sensor arrangement shown in Figure 1.

[0111] The component 110 of the system 200 comprises exactly one magnetic tape 123 and, adjacent to it, a region 130 within the section of magnetizable material 120. The magnetic tape 123 extends circumferentially 112 with its magnetization direction 124 oriented circumferentially 112 when free of torsional load. According to this embodiment, all sensors 20-32' are arranged at the same radial distance 9 from the surface of the component 110, without being limited to this distance. At least two sensors 20-32' can also have different radial distances. Analogous to Figure 1, the first sensor unit 2, with its sensors 20, 22, is associated with the magnetic tape 123 and, as described in Figure 1, forms the first channel K1, which is separate from the second channel K2.

[0112] The sensors 30, 32 of the second sensor unit 3 are assigned to the area 130 adjacent to the magnetic tape 123. They are configured to detect a radial field component 6 of the magnetic field emitted by the component 110 in the area 130 and, as described in Figure 1, form the second channel K2, which is separate from the first channel K1.

[0113] Figure 12 schematically depicts the shape of the radial field component 6 resulting from a torsional load T of a certain magnitude in component 110. This component represents the magnetic field emitted by the magnetic tape 123 and the adjacent areas 130 in section 120 across component 110 along the axial direction 111 in a Cartesian coordinate system. Outside the magnetic tape 123, the strength of the radial field component 6 decreases successively with increasing distance without exceeding the zero line. The signal formed by the differential D2 of the second sensor unit 3, more precisely the amplitude of the signal, is therefore smaller than in the embodiment according to Figures 1 and 2. The differential D1 is also somewhat smaller than in Figure 2. This does not change the fact that, just as in the embodiment of Figures 1 and 2, the signals of channels K1 and K2 can be compared with each other as described above to infer the presence of an external field.This requires precisely the different signal amplitudes of the first channel K1 and the second channel K2 at a given torque. Where applicable, all individual features illustrated in the exemplary embodiments can be combined and / or exchanged without departing from the scope of the invention.

[0114] List of reference signs

[0115] 2 First sensor unit

[0116] 20 First sensor of the first sensor unit

[0117] 21 Predefined distance between the sensors

[0118] 22 Second sensor of the first sensor unit

[0119] 27 End of a magnetic tape

[0120] 28 Axial offset

[0121] 29 Offset in circumferential direction

[0122] 3 Second sensor unit

[0123] 30 First sensor of the second sensor unit

[0124] 31. Predefined distance between the sensors

[0125] 32 Second sensor of the second sensor unit

[0126] 4 Axial distance

[0127] 5 Evaluation device

[0128] 6 Radial field component

[0129] 61-64 Extrema of the radial field component

[0130] 7 Sensor arrangement

[0131] 8 carriers

[0132] 9 Radial distance

[0133] 100 System

[0134] 110 component

[0135] 111 Axial direction

[0136] 112 Circumferential direction

[0137] 120 Section of magnetizable material

[0138] 121 First outer magnetic tape

[0139] 122 Magnetization direction of the first outer magnetic tape

[0140] 123 Medium magnetic tape

[0141] 124 Magnetization direction of the middle magnetic tape

[0142] 125 Second outer magnetic tape

[0143] 126 Magnetization direction of the second outer magnetic tape

[0144] 127 Width of a magnetic tape

[0145] T Torsional load (torque) in Nm

[0146] D1 Differential of the signals from the sensors of the first sensor unit

[0147] D2 Differential of the signals from the sensors of the second sensor unit

[0148] K1 First Channel

[0149] K2 Second channel m1 Slope of the signal waveform of the first channel K1 versus the torsional load T m2 Slope of the signal waveform of the second channel K2 versus the torsional load T

Claims

Claims 1. System (100) for detecting a torsional load (T) acting on a torque-transmitting component (110), comprising a component (110) with a section (120) made of magnetizable material in which at least two circumferentially extending magnetic strips (121, 123, 125) are arranged successively in an axial direction (111) of the component (110), wherein adjacent magnetic strips (121, 123, 125) each have opposite magnetization directions (122, 124, 126), and a first sensor unit (2) with two sensors (20, 22) arranged at a predetermined distance (21) from each other in the axial direction (111) and assigned to a first magnetic strip (123) for detecting a radial field component (6) of the assigned magnetic strip. (123) are set up and form a first channel (K1), characterized by,that the system (100) further comprises: a second sensor unit (3) with two sensors (30, 32) arranged at a predetermined distance (31) in the axial direction (111) from each other, which are assigned to a second magnetic tape (121, 125) adjacent to the first magnetic tape (123), are configured to detect a radial field component (6) of the assigned magnetic tape (121, 125) and form a second channel (K2) separate from the first channel (K1).

2. System (100) according to claim 1, characterized in that the component (110) in its section (120) made of magnetizable material comprises three magnetic tapes (121, 123, 125) extending in the circumferential direction (112) and arranged successively in the axial direction (111), wherein adjacent magnetic tapes (121, 123, 125) each have opposite magnetization directions (122, 124, 126), wherein the sensors (20, 22) of the first sensor unit (2) are assigned to the middle magnetic tape (123) of the three magnetic tapes (121, 123, 125) and the sensors (30, 32) of the second sensor unit (3) are assigned to one of the two outer magnetic tapes (121, 125) of the three magnetic tapes (121, 123, 125).

3. System (100) according to one of the preceding claims, characterized in that for each sensor unit (2, 3) one sensor (20, 30) is assigned to a first end (27) and the other sensor (22, 32) is assigned to the other end (27) of the associated magnetic tape (121 , 123, 125), wherein with respect to the axial direction (111 ) each sensor (20, 22, 30, 32) is either positioned directly at the end (27) or is positioned offset by a predetermined axial offset (28) in the axial direction (111 ) to the assigned end (27) in the direction of the axial center of the associated magnetic tape (121 , 123, 125).

4. System (100) according to the preceding claim, characterized in that the predetermined axial offset (28) is less than or equal to 0.25 times the width (127) in the axial direction (111) of the associated magnetic tape (121, 123, 125), optionally less than or equal to 0.2, less than or equal to 0.15, less than or equal to 0.10 times the width (127), and / or the predetermined axial offset (28) is optionally greater than or equal to 0.025, 0.05, 0.075 or 0.1 times the width (127) in the axial direction (111) of the associated magnetic tape (121, 123, 125).

5. System (200) for detecting a torsional load (T) acting on a torque-transmitting component (110), comprising a component (110) with a section (120) made of magnetizable material in which a circumferentially extending magnetic tape (123) with a circumferentially oriented magnetization direction (124) is arranged, and a first sensor unit (2) with two sensors (20, 22) arranged at a predetermined distance (21) from each other in the axial direction (111), which are associated with the magnetic tape (123), are configured to detect a radial field component (6) of the magnetic tape (123) and form a first channel (K1), characterized in that the system (100) further comprises: a second sensor unit (3) with two sensors (30, 22) arranged at a predetermined distance (31) from each other in the axial direction (111). 32), which are assigned to an area (130) adjacent to the magnetic tape (123),are set up to detect a radial field component (6) of a magnetic field (131) emitted by the component and form a second channel (K2) separate from the first channel (K1).

6. System (200) according to the preceding claim, characterized in that a sensor (20) of the first sensor unit (2) is connected to a first end (27) of the magnetic tape (123) and the other sensor (22) of the first sensor unit (2) is assigned to the other end (27) of the magnetic tape (123), and wherein a sensor (32) of the second sensor unit (3) is assigned to a first end (27) of the magnetic tape (123) and the other sensor (30) of the second sensor unit (3) is arranged further away from the magnetic tape (123) by the predetermined distance (31) than the sensor (32) of the second sensor unit (3) assigned to the end (27) of the magnetic tape (123), wherein, with respect to the axial direction (111), the sensors (20, 22) of the first sensor unit (2) are either positioned directly at the end (27) or are positioned offset by a predetermined axial offset (28) in the axial direction (111) to the assigned end (27) in the direction of the axial center of the magnetic tape (123),and the sensor (32) of the second sensor unit assigned to the end (27) is either positioned directly at the end (27) or is positioned offset by a predetermined axial offset (28) in the axial direction (111) to the assigned end (27) in the direction away from the magnetic tape (123).

7. System (200) according to the preceding claim, characterized in that the predetermined axial offset (28) is less than or equal to 0.25 times the width (127) in the axial direction (111) of the magnetic tape (123), optionally less than or equal to 0.2, less than or equal to 0.15, less than or equal to 0.10 times the width (127), and / or the predetermined axial offset (28) is optionally greater than or equal to 0.025, 0.05, 0.075 or 0.1 times the width (127) in the axial direction (111) of the magnetic tape (123).

8. System (100, 200) according to one of the preceding claims, characterized in that the sensors (20, 22, 30, 32) are arranged radially inside or outside the respective magnetic tapes (121, 123, 125) and / or the surface of the component (110) associated with them.

9. System (100, 200) according to one of the preceding claims, characterized in that each of the sensors (20, 22, 30, 32) of at least one of the sensor units (2, 3) is arranged on its own carrier (8), and / or that the two sensors (20, 22, 30, 32) of at least one of the sensor units (2, 3) are arranged on a common carrier (8), or the sensors (20, 22, 30, 32) of the first and second sensor units (2, 3) are arranged on a common carrier (8).

10. System (100, 200) according to one of the preceding claims, characterized in that the sensors (20, 22) of the first sensor unit (2) are arranged at the same height when viewed in the circumferential direction (112), and / or the sensors (30, 32) of the second sensor unit (3) arranged at the same height when viewed in the circumferential direction (112), optionally the sensors (20, 22, 30, 32) of both sensor units (2, 3) are arranged at the same height when viewed in the circumferential direction (112).

11. System (100, 200) according to one of the preceding claims, characterized in that the system (100) further comprises an evaluation device (5) which is configured to acquire and / or evaluate the signals of the first channel (K1) and the signals of the second channel (K2), wherein optionally the evaluation device (5) is configured to convert the signals of the channels (K1, K2) into a torque (T), wherein optionally the evaluation device (5) is configured to compare the acquired signals of the first and second channels (K1, K2) and / or the torques (T) calculated therefrom, optionally to relate them.

12. Method for detecting a torsional load (T) acting on a torque-transmitting component (110), comprising: Providing (S201) a component (1 10) with a section (120) of magnetizable material in which at least two circumferentially extending magnetic tapes (121 , 123, 125) are arranged successively in an axial direction (1 11 ) of the component (1 10), wherein adjacent magnetic tapes (121 , 123, 125) each have opposite magnetization directions (122, 124, 126), Providing (S202) a first sensor unit (2) with two sensors (20, 22) arranged at a predetermined axial distance (21) in the axial direction (11 1) to each other, which are assigned to a first magnetic tape (123), are configured to detect a radial field component (6) of the assigned magnetic tape (123) and form a first channel (K1), characterized in that the method further comprises: Providing (S203) a second sensor unit (3) with two sensors (30, 32) arranged at a predetermined axial distance (31) in the axial direction (111) to each other, which are assigned to a second magnetic tape (121, 125) adjacent to the first magnetic tape (123), are designed to detect a radial field component (6) of the assigned magnetic tape (121, 125) and form a second channel (K2) separate from the first channel (K1).

13. Method (100) according to claim 9, characterized in that the component (110) in its section (120) made of magnetizable material comprises three magnetic tapes (121, 123, 125) extending in the circumferential direction (112) and arranged successively in the axial direction (111), wherein adjacent magnetic tapes (121, 123, 125) each have opposite magnetization directions (122, 124, 126), wherein the sensors (20, 22) of the first sensor unit (2) are assigned to the middle magnetic tape (123) of the three magnetic tapes (121, 123, 125) and the sensors (30, 32) of the second sensor unit (3) are assigned to one of the two outer magnetic tapes (121, 125) of the three magnetic tapes (121, 123, 125).

14. Method for detecting a torsional load acting on a torque-transmitting component, comprising: Providing (S201 ) a component (1 10) with a section (120) of magnetizable material in which a circumferentially extending (112) magnetic tape (123) with circumferentially oriented magnetization direction (124) is arranged, and Providing (S203) a first sensor unit (2) with two sensors (20, 22) arranged at a predetermined distance (21) in the axial direction (111) to each other, which are assigned to the magnetic tape (123), are configured to detect a radial field component (6) of the magnetic tape (123) and form a first channel (K1), characterized in that the method further comprises: Providing a second sensor unit (3) with two sensors (30, 32) arranged at a predetermined distance (31) in the axial direction (111) to each other, which are assigned to an area (130) adjacent to the magnetic tape (123), are designed to detect a radial field component (6) of a magnetic field (131) emitted by the component and form a second channel (K2) separate from the first channel (K1).

15. Method according to one of claims 12 or 14, characterized in that the method further comprises: acquiring (S204) the signals of the first channel (K1 ) and the signals of the second channel (K2) and evaluating the signals of the first channel and the signals of the second channel, optionally converting the signals of the channels into a torque (T), optionally comparing the detected signals of the first and second channels (K1 , K2) and / or calculated torques (T) from them, optionally relating them (S205).

Images