Measurement value detection device for an inductive sensor assembly

Abstract

The present invention relates to a measurement detection device for an inductive sensor assembly having a circuit carrier (11) having at least one excitation structure (13) and at least one receiving structure (14), wherein the at least one excitation structure (13) includes at least one excitation coil (13A) having at least one winding surrounding the at least one receiving structure (14) from both sides, wherein the at least one receiving structure (14) includes at least two receiving coils (16), each having at least one winding, wherein at least one of the receiving coils (16) is electrically connected to at least one compensation structure (20) arranged outside the at least one excitation structure (13) and configured such that the largest of the offset voltages induced by the at least one excitation structure (13) occurring at the at least two receiving coils (16) has a value less than the maximum possible value determined by the construction. The invention also relates to an inductive sensor assembly having such a measurement detection device (10).

Description

Technical Field

[0001] This invention relates to a measurement detection device for an inductive sensor assembly. The subject matter of this invention also relates to an inductive sensor assembly having at least one such measurement detection device. Background Technology

[0002] Inductive sensor assemblies are known from the prior art, comprising a measurement detection device and at least one coupling device. The measurement detection device has at least one excitation structure and at least one receiving structure, and the coupling device is also referred to as a target. Furthermore, the at least one excitation structure includes an excitation coil. The at least one coupling device includes at least one conductive coupling element. The at least one receiving structure has at least one, but typically two, receiving coils. A high-frequency current flows through the at least one excitation coil, generating an alternating magnetic field that induces eddy currents in the at least one coupling device. Here, the inductive coupling between the at least one excitation coil and the at least one receiving coil depends on the position of the corresponding coupling device. The current position of the coupling device can be inferred from the voltage signal induced in the at least one receiving coil, and thus the current position of the object whose motion should be detected can be inferred.

[0003] An inductive position sensor is known from document DE 100 26 019 B4. This inductive position sensor includes an oscillating circuit that generates a periodic alternating voltage signal and couples it into an excitation coil, multiple receiving coils, an evaluation circuit, and a movable inductive coupling element that affects the strength of the inductive coupling between the excitation and receiving coils. The excitation and receiving coils are constructed as conductive lines on a carrier plate. Each receiving coil has two taps through which the voltage induced in the associated receiving coil by the excitation coil can be extracted. The evaluation circuit is arranged within the geometry of the transmitting and / or receiving coils and is used to evaluate the signal induced in the receiving coils. The effective area of ​​the receiving coils in the starting and / or ending regions of the sensor is configured such that, in the absence of a movable element, the voltage induced in the receiving coils by the excitation coils and extracted at the associated taps of the receiving coils is zero. Summary of the Invention

[0004] The measurement detection device for an inductive sensor assembly having the features of independent claim 1 and the corresponding inductive sensor assembly having the features of independent claim 11 have the advantage that the maximum occurrence of the offset voltage can be reduced without reducing the measurement range by adapting the offset voltages induced in at least two receiving coils in at least one excitation structure to each other.

[0005] In embodiments of the measurement detection device, by purposefully extending the coil profile of at least one receiving coil in the receiving coils using at least one compensation structure, it is possible to compensate for the offset of the corresponding receiving coil signal as well as possible through the coil layout itself. Since the induced offset voltage generated without at least one coupling device relative to the induced and demodulated signal in the receiving coil of at least one excitation structure is compensated by the evaluation and control unit to keep the angular or positional error of the inductive sensor assembly as small as possible, reducing the maximum offset voltage has a positive impact on the implementation of the evaluation and control unit. Without compensation for the offset voltage, the angular or positional error of the inductive sensor assembly would be unacceptably high, rendering the inductive sensor assembly unusable. Commercially available ASICs (Application-Specific Integrated Circuits) for implementing the evaluation and control unit are limited in terms of the maximum compensable offset voltage. For multi-coil designs, especially in confined installation spaces, this limit is often reached without further measures when at least one excitation coil cannot be arranged further away from at least two receiving coils. The embodiment of the measurement detection device for inductive sensor assemblies according to the present invention provides a feasible solution for reducing the maximum offset voltage without increasing the installation space or making expensive adjustments to the evaluation and control unit.

[0006] The embodiments of the present invention can simultaneously satisfy the requirements for installation space, ASIC (Application-Specific Integrated Circuit), and angular error by selecting a layout for at least one receiving structure such that the offset is compensated by the layout itself, rather than primarily by the ASIC. This allows, for example, the sensitive area of ​​the ASIC's analog-to-digital converter to be manipulated as well as possible without "losing" the conversion range due to the offset range.

[0007] Furthermore, embodiments of the present invention enable the initial selection of an ideal coil profile and coil orientation for position measurement, and then the independent compensation of the offset using at least one compensation structure. The core of the invention lies in using at least one compensation structure to extend the coil profile of at least one of at least two receiving coils to compensate for the offset of the corresponding receiving coil. For this purpose, the coil profile is extended outside the transmitting coil by at least one compensation structure having at least one additional winding.

[0008] The ever-increasing demands for linearity in position sensors often necessitate measures in the coil design of at least one receiving coil, which can negatively impact other factors such as installation space or amplitude. Using embodiments of the present invention, offset can be reduced without additional measures. Offset compensation enables smaller position determination errors because even when offset is corrected in an ASIC (Application-Specific Integrated Circuit), dynamic tolerances, temperature effects, aging, and especially fluctuations in the transmitting coil voltage can cause deviations between the actual and corrected offset. This problem is eliminated or significantly mitigated when offset is eliminated through at least one compensation structure. Furthermore, this potentially allows for the use of more cost-effective ASICs or microcontrollers because the coverage of offset correction can be reduced.

[0009] Embodiments of the present invention provide a measurement detection device for an inductive sensor assembly, comprising a circuit carrier having at least one excitation structure and at least one receiving structure. The at least one excitation structure includes at least one excitation coil having at least one winding, the at least one excitation coil surrounding the at least one receiving structure from both sides. The at least one receiving structure includes at least two receiving coils, each having at least one winding. Here, at least one of the receiving coils is electrically connected to at least one compensation structure, the at least one compensation structure being arranged outside the at least one excitation structure, and is configured such that the largest offset voltage among the offset voltages induced by the at least one excitation structure occurring at the at least two receiving coils has a value less than the possible maximum value determined by the construction method.

[0010] Furthermore, an inductive sensor assembly for detecting the motion of a movable body is proposed, comprising at least one coupling device and such a measurement detection device. The at least one coupling device or measurement detection device is coupled to the movable body whose motion should be detected. At least one excitation structure is arranged on the circuit carrier of the measurement detection device. This at least one excitation structure is coupled to an evaluation and control circuit that couples a periodic alternating signal into the at least one excitation structure during operation. The at least one coupling device is configured to influence the inductive coupling between the at least one excitation structure of the measurement detection device and at least one receiving structure. Here, at least one evaluation and control unit is configured to receive and evaluate the signal induced in the at least one receiving structure and determine the current relative position of the movable coupling device with respect to the at least one receiving structure and / or the current position of the movable body.

[0011] Inductive sensor components can be implemented, for example, as linear displacement sensors, in which case a body performs a detected translational motion along a motion axis; or as rotational angle sensors or rotor position sensors, in which case a body performs a detected rotational motion about a rotation axis. In the case of inductive rotational sensors, the measurement detection device preferably has a space-saving "C" shape that can be fitted onto the shaft. This simplifies the manufacturing process for integrating the inductive sensor components. The coil layout of such measurement detection devices can be determined by transforming the polar coordinates of the coil layout of the measurement detection device for inductive linear displacement sensors to Cartesian coordinates, with an appropriate selection of the origin (0, 0).

[0012] Here, the evaluation and control unit can be understood as an electrical component or circuit that preprocesses, processes, or evaluates detected sensor signals. The evaluation and control unit is preferably implemented as an ASIC module (ASIC: Application-Specific Integrated Circuit). The evaluation and control unit may have at least one interface, which may be constructed in hardware and / or software form. In the case of hardware construction, the interface may, for example, be part of an ASIC module. However, the interface may also be a separate integrated circuit or at least partially composed of discrete structural elements. In the case of software construction, the interface may be a software module, which, for example, exists on a microcontroller along with other software modules.

[0013] In the following text, the excitation structure can be understood as an excitation coil with a predetermined number of windings that transmits an alternating signal coupled in by the evaluation and control unit.

[0014] Advantageous improvements can be made to the measurement detection device for the inductive sensor assembly given in independent claim 1 and the inductive sensor assembly given in independent claim 11 by means of the measures and improvements listed in the dependent claims.

[0015] It is particularly advantageous that the maximum absolute values ​​of the offset voltages appearing at the two receiving coils of at least one receiving structure can be equal or equal to zero.

[0016] In an advantageous design of the measurement detection device, at least one compensation structure can be implemented as a planar compensation coil with at least one winding. This allows for the particularly convenient and cost-effective implementation of at least one compensation structure. Here, the conductor line segment of at least one winding of the at least one compensation structure can be constructed in one or at least two planes of the circuit carrier. The conductor line segments of the compensation structure arranged in different planes of the circuit carrier can be electrically connected to each other through plated vias. As is consistent with the principle of this sensor, the size of the enclosed area affects the measured induced voltage. By implementing at least one compensation structure with multiple windings, a larger effective area can be achieved within a limited space. Thus, the offset caused by the coil geometry of at least one receiving coil can be compensated by a predetermined number of windings of the at least one compensation structure, wherein the number of windings can be matched with the magnitude of the offset. The exact shape of the at least one compensation structure can be arbitrarily chosen here, and thus can be appropriately placed according to the layout of the circuit carrier. Advantageously, the shape of the at least one compensation structure can be selected such that it avoids overlap with the excitation structure and / or the receiving structure, thereby placing the compensation structure in the "space" between the excitation structure and the receiving structure. Thus, the number of layers of the circuit board can remain unchanged and does not need to be increased. This enables cost advantages.

[0017] In another advantageous design of the measuring value detection device, the flow direction in at least one compensation structure can be aligned with the flow direction in the corresponding receiving coil. This means that the flow direction of the conductor lines of at least one compensation structure can be in the same direction as the flow direction of the starting or ending segment of one of the receiving coils. Therefore, at least one compensation structure can be located outside the excitation coil and have the same surrounding direction as the last enclosed surface. This is because the magnetic fields inside and outside the excitation coil point in different directions. Thus, at least one compensation structure compensates for the offset caused by the following: In a receiving structure implemented as a two-phase system with sine and cosine coils, for the cosine coil, the surfaces at the short ends of the excitation coil point in the same direction. For the sine coil, they point in opposite directions, i.e., the sine coil is asymmetrically located within the excitation coil, so that all the generated induced voltages cancel each other out. For such a two-phase receiving structure with sine and cosine coils, at least one compensation structure is preferably used for the cosine coil. The sine coil is largely free from offset due to its construction. The at least one compensation structure can also be used if, for example, an offset is systematically induced in one of the receiving coils due to surrounding conductive metal components. The naming of sine and cosine coils here exemplarily refers to a two-phase system of receiving structures. Typically, at least one compensation structure can be designed and installed for any receiving coil of at least one receiving structure of a measurement detection device. In particular, in a multiphase system with M phases or M receiving coils, at least one compensation structure can preferably be used for (M-1) receiving coils. This may differ for redundant receiving structures with phase shifts.

[0018] In another advantageous design of the measurement detection device, at least two receiving coils may have a predetermined phase shift or a predetermined distance between them.

[0019] In another advantageous design of the measurement detection device, at least one winding of at least two receiving coils may each have two loop structures, each loop structure having multiple loop segments, and constructed in at least two planes of the circuit carrier. Here, the segments of the respective loop structures arranged in different planes of the circuit carrier are electrically connected to each other via electroplated through-holes. Furthermore, the two loop structures of each winding of the at least two receiving coils may have a phase shift of 180° relative to each other and opposite flow directions. Additionally, the segments of the respective loop structures arranged in different planes of the circuit carrier may, for example, correspond to half a cycle, a quarter cycle, or an eighth cycle of repeating loop segments. The distance between adjacent loop structures of at least one receiving structure may be based on the number of receiving structures, the number of receiving coils, the number of windings of at least one receiving coil, and the periodicity of at least one receiving structure. Here, the distance between the loop structures of the windings of at least one receiving coil of the same receiving structure may be equal. Equal distances enable optimal utilization of existing installation space, thereby maximizing the number of windings while avoiding violations of design rules. Preferably, the loop structures of the respective windings of at least one receiving coil may be implemented as substantially overlapping. Alternatively, the distance between the loop structures of the windings of at least one receiving coil may be different, especially when at least one receiving coil has more than two windings.

[0020] In another advantageous design of the measurement detection device, the two loop structures of each winding of at least two receiving coils can each correspond to a segment having at least one period of mathematical oscillation. Here, the mathematical oscillation can have a sinusoidal shape, a rectangular shape, a triangular shape, a trapezoidal shape, or a mixed shape. Of course, the periodically repeating loop segment can also have other suitable shapes or mixed shapes. Attached Figure Description

[0021] Embodiments of the present invention are shown in the accompanying drawings and described in detail below. In the drawings, the same reference numerals denote components or elements that perform the same or similar functions.

[0022] Figure 1 A schematic top view of a first embodiment of an inductive sensor assembly according to the present invention is shown, the inductive sensor assembly having a first embodiment of a measurement value detection device according to the present invention, wherein the circuit carrier of the measurement value detection device is transparently shown.

[0023] Figure 2 It shows Figure 1 A schematic perspective view of the end region of a measurement detection device according to the present invention, the measurement detection device having a first embodiment of a compensation structure for a receiving coil of a receiving coil of the measurement detection device according to the present invention.

[0024] Figure 3 It shows Figure 1 A schematic perspective view of the end region of the measurement value detection device according to the present invention, the measurement value detection device having a second embodiment of a compensation structure for a receiving coil of a receiving coil of the measurement value detection device according to the present invention.

[0025] Figure 4 A schematic top view of a second embodiment of an inductive sensor assembly according to the invention is shown, the inductive sensor assembly having a second embodiment of a measurement value detection device according to the invention, wherein the circuit carrier of the measurement value detection device is transparently shown. Detailed Implementation

[0026] If possible Figures 1 to 4 As can be seen, the illustrated embodiment of the measurement value detection device 10 for the inductive sensor assembly 1 according to the present invention includes a circuit carrier 11 having at least one excitation structure 13 and at least one receiving structure 14. The at least one excitation structure 13 includes at least one excitation coil 13A having at least one winding that surrounds the at least one receiving structure 14 from both sides. The at least one receiving structure 14 includes at least two receiving coils 16, each having at least one winding. Here, at least one of these receiving coils 16 is electrically connected to at least one compensation structure 20, which is arranged outside the at least one excitation structure 13 and is configured such that the largest offset voltage among the offset voltages induced by the at least one excitation structure 13 occurring at the at least two receiving coils 16 has a value less than the possible maximum value determined by the construction method.

[0027] For example, it is also possible to... Figures 1 to 4 As can be seen, each winding in at least two receiving coils 16 has two loop structures 18A and 18B, each loop structure comprising multiple loop segments SA, and constructed in at least two planes of the circuit carrier 11. The segments of the respective loop structures 18A and 18B arranged in different planes of the circuit carrier 11 are electrically connected to each other via electroplated through-holes DK. The two loop structures 18A and 18B of each winding of the at least two receiving coils 16 have a 180° phase shift and opposite flow directions. This can also be seen from… Figure 1As can be seen, the loop segments SA of the two loop structures 18A and 18B are periodically repeated. This means that the two loop structures 18A and 18B of each winding of at least two receiving coils 16 each correspond to a segment 5 having at least one period of mathematical oscillation. In the illustrated embodiment, the mathematical oscillation, more precisely, the repeated loop segment SA, has a sine shape and a cosine shape, respectively. In an alternative embodiment not shown, the mathematical oscillation, more precisely, the repeated loop segment SA, has a rectangular shape, a triangular shape, a trapezoidal shape, or a mixed shape. Furthermore, in the illustrated embodiment, the segments of the respective loop structures 18A and 18B arranged in different planes of the circuit carrier 11 correspond to half a period of the repeated loop segment SA. Here, electroplated vias DK connect the segments of each loop structure 18A, 18B arranged in the lower plane (second plane) of the circuit carrier 11 to the segments of each loop structure 18A, 18B arranged in the upper plane (first plane) of the circuit carrier 11. These electroplated vias are respectively arranged at the upper edge and the lower edge of the receiving structure 14. Alternatively, the segments of each loop structure 18A, 18B arranged in different planes of the circuit carrier 11 may correspond to a quarter-cycle or an eighth-cycle.

[0028] In the illustrated embodiment of the measurement detection device 10, the flow direction in the first loop structure 18A of at least two windings of at least two receiving coils 16 is along the positive x-direction (from left to right in this case), and the flow direction in the second loop structure 18B of at least two windings of at least two receiving coils 16 is along the negative x-direction (from right to left in this case). By means of two loop structures 18A and 18B arranged offset from each other at half a period, more precisely 180° along the motion trajectory BB and having opposite flow directions, surfaces with different surface normals are respectively enclosed between the first loop structure 18A and the second loop structure 18B of at least two windings of at least two receiving coils 16. According to the periodicity of at least two windings of at least two receiving coils 16, a corresponding number of surfaces are enclosed between the two loop structures 18A and 18B of at least one winding.

[0029] For example, it is also possible to... Figure 1As can be seen, in the first embodiment shown, the inductive sensor assembly 1 is implemented as an inductive linear displacement sensor and includes at least one coupling device 3 and a measurement detection device 10 according to the invention for detecting the motion of a linearly movable object (not shown). Here, at least one coupling device 3 or the measurement detection device 10 is coupled to a movable object (not shown) whose linear motion along a motion trajectory BB should be detected. At least one excitation structure 13 is arranged on the circuit carrier 11 of the measurement detection device 10. The at least one excitation structure 13 is coupled to at least one evaluation and control circuit 12, which couples a periodic alternating signal into the at least one excitation structure 13 during operation. The at least one coupling device 3 includes a conductive coupling element 3.1 and is implemented to influence the inductive coupling between the at least one excitation structure 13 of the measurement detection device 10 and at least one receiving structure 14. At least one evaluation and control unit 12 is implemented to receive and evaluate the signal induced in the at least one receiving structure 14 and determine the current relative position of the movable coupling device 3 with respect to the at least one receiving structure 14 and / or the current position of the movable object.

[0030] To maintain clarity, Figures 1 to 4 The electrical connection of at least two receiving coils 16 of at least one receiving structure 14 to the evaluation and control unit 12 is not shown. This does not represent a short circuit of at least one receiving coil 16. Of course, at least one receiving coil 16 may be separated at a suitable location, such as at the plated through-hole DK, and guided to the evaluation and control unit 12 via additional conductor lines, so that the induced signal can be evaluated there.

[0031] For example, it is also possible to... Figures 1 to 4 As can be seen, the illustrated embodiment of the measurement value detection device 10 according to the present invention correspondingly includes a receiving structure 14, which correspondingly has two receiving coils 16. Due to the sinusoidal and cosine shapes of the loop structures 18A and 18B of the two receiving coils 16, when the geometric profile of one of the two receiving coils 16, more precisely, the loop structures 18A and 18B, have the maximum possible value in the y-direction at one end of the receiving structure 14, more precisely relative to... Figure 1When the zero line, indicated by the dashed line, is offset "up" or "down" to its maximum possible value, the maximum possible value of the offset voltage, determined by the construction method, occurs. This offset voltage is induced in the two receiving coils 16 by at least one excitation structure 13 without coupling device 3. When the geometric profile of one of the two receiving coils 16, more precisely, the loop structures 18A and 18B, respectively has the minimum possible value relative to the zero line at one end of the receiving structure 14, the minimum possible value of the offset voltage, determined by the construction method, occurs. This means that the loop structures 18A and 18B "pass through zero," have no offset, or have a value of "0."

[0032] In the receiver structure 14 with two receiver coils 16 known from the prior art, the loop structures 18A and 18B of the first receiver coil 16A are respectively "passing zero" or have no offset or a value of "0". This results in the minimum possible value of the offset voltage, determined by the construction method, and the loop structures 18A and 18B of the second receiver coil 16B have the maximum possible value in the y-direction, i.e., relative to... Figure 1 The maximum possible offset of the zero line, indicated by the dashed line, to either "up" or "down" results in a maximum possible value for the offset voltage, determined by the construction method. This means that, in the known receiver structure 14, the offset voltage with the largest amount occurring at the two receiver coils 16 has a maximum possible value determined by the construction method.

[0033] For example, it is also possible to... Figures 1 to 4 As can be seen, in the illustrated embodiment of the measurement detection device 10, at least one compensation structure 20 is implemented as a planar compensation coil 22 having at least one winding. Here, the conductor line segment of at least one winding of the at least one compensation structure 20 is constructed in one or at least two planes of the circuit carrier 11. The conductor line segments of the compensation structure 20 arranged in different planes of the circuit carrier 11 are electrically connected to each other through electroplated through-holes DK. Furthermore, the flow direction in the at least one compensation structure 20 is consistent with the flow direction in the corresponding receiving coil 16.

[0034] For example, it is also possible to... Figure 1 and Figure 2As can be seen, a first embodiment of the inductive sensor assembly 1A according to the present invention includes a first embodiment of the measurement value detection device 10A according to the present invention, which includes a receiving structure 14A and an excitation structure 13. In the illustrated first embodiment of the inductive sensor assembly 1A, the excitation structure has an excitation coil 13A having six windings arranged in two planes of the circuit carrier 11. This means that three windings are arranged in each plane of the circuit carrier 11. The receiving structure 14A includes two receiving coils 16A and 16B, each having windings and constructed in the two planes of the circuit carrier 11. Here, the first receiving coil 16A forms a sinusoidal channel, and the second receiving coil 16B forms a cosine channel. Each winding of the two receiving coils 16A and 16B has two loop structures 18A and 18B, respectively, which have multiple loop segments SA. In the illustrated embodiment, the loop segments SA of the two loop structures 18A and 18B of each winding have a sinusoidal shape and opposite flow directions. The loop structures 18A and 18B of the windings of the two receiving coils 16A and 16B are arranged staggered from each other at a predetermined distance, which corresponds to a 90° phase shift between the two receiving coils 16A and 16B. Here, the ends of the respective loop structures 18A and 18B of the corresponding windings of the two receiving coils 16A and 16B are respectively connected to each other at the end region of the receiving structure 14A, so that the flow direction is reversed accordingly in the respective windings.

[0035] For example, it is also possible to... Figure 1 and Figure 2 As can be seen, in the first embodiment of the measurement detection device 10A shown, the compensation structure 20A, which is arranged outside the excitation structure 13 and implemented as a planar compensation coil 22, is electrically connected to the second receiving coil 16B of the receiving structure 14A. The planar compensation coil 22 includes a plurality of rectangular windings, the conductor line segments of which are constructed in two planes of the circuit carrier 11. In the first embodiment of the compensation structure 20A shown, two windings of the compensation coil 22 are arranged in the two planes of the circuit carrier 11 respectively. However, this principle can be extended to any (even) number of planes of the circuit carrier, each plane having an arbitrary number of windings. Here, different numbers of windings of the compensation coil 22 can be arranged in different planes of the circuit carrier. The conductor line segments of the compensation structure 20A arranged in different planes of the circuit carrier 11 are electrically connected to each other through electroplated through-holes DK. Here, the windings of the compensation coil 22 in different planes of the circuit carrier 11 have the same flow direction, which is consistent with the flow direction in the corresponding second receiving coil 16B.

[0036] For example, it is also possible to... Figure 3As can be seen, in the second embodiment of the measurement value detection device 10B of the second embodiment of the inductive sensor assembly 1B, similar to the first embodiment, the compensation structure 20B, which is arranged outside the excitation structure 13 and implemented as a planar compensation coil 22, is electrically connected to the second receiving coil 16B of the receiving structure 14A. Similar to the first embodiment of the inductive sensor assembly 1A, the excitation structure 13 of the second embodiment of the inductive sensor assembly 1B includes an excitation coil 13A having six windings arranged in two planes of the circuit carrier 11. The planar compensation coil 22 includes multiple rectangular windings, whose conductor line sections differ from those in the first embodiment of the measurement value detection device 10A, being constructed only in one plane of the circuit carrier 11. In the second embodiment of the compensation structure 20B shown, the planar compensation coil 22 includes two windings arranged in one plane of the circuit carrier 11. Only a conductor line section is arranged in the second plane of the circuit carrier 11, which electrically connects one end of the second receiving coil 16B to the compensation coil 22 of the compensation structure 20B through a plated through-hole DK. The second embodiment of the compensation structure 20B shown is comparable Figure 1 and Figure 2 The first embodiment of the compensation structure 20A shown in the figure compensates for smaller offset values.

[0037] For example, it can also be found from Figure 4 As can be seen, in the illustrated third embodiment, the inductive sensor assembly 1C is implemented as an inductive rotational angle sensor or rotor position sensor, wherein a movable body (not shown) performs a detected rotational motion about a rotational axis. Similar to the embodiments described above, to detect the motion of the rotatable object (not shown), the inductive sensor assembly 1C includes at least one coupling device (not shown in detail) and a measurement detection device 10C according to the invention, which, in the illustrated third embodiment of the inductive sensor assembly 1C, has a space-saving "C" shape that can be fitted onto a shaft. Here, at least one coupling device or measurement detection device 10C is coupled to the movable body (not shown) whose rotational motion should be detected. At least one excitation structure 13 is arranged on the circuit carrier 11 of the measurement detection device 10C. This at least one excitation structure 13 is coupled to an evaluation and control circuit 12, which couples a periodic alternating signal into the at least one excitation structure 13 during operation. The at least one coupling device includes a conductive coupling element and is implemented to influence the inductive coupling between the at least one excitation structure 13 of the measurement detection device 10C and at least one receiving structure 14. At least one evaluation and control unit 12 is implemented to receive, demodulate and evaluate signals sensed in at least one receiving structure 14, and determine the current relative position of the movable coupling device with respect to at least one receiving structure 14 and / or the current position of the movable body.

[0038] For example, it can also be found from Figure 4 As can be seen, the third embodiment of the measurement detection device 10C includes a receiving structure 14B and an excitation structure 13. In the third embodiment of the inductive sensor assembly 1C, the excitation structure includes an excitation coil 13C having six windings arranged in two planes of the circuit carrier 11. This means that three windings are arranged in each of the two planes of the circuit carrier 11. The receiving structure 14B includes two receiving coils 16A and 16B, each having windings and constructed in the two planes of the circuit carrier 11. Each winding of the two receiving coils 16A and 16B has two loop structures 18A and 18B, which, in the illustrated embodiment, have sinusoidal and cosine shapes and opposite flow directions, respectively. The loop structures 18A and 18B of the windings of the two receiving coils 16A and 16B are staggered from each other at a predetermined distance. Here, the ends of the respective loop structures 18A and 18B of the windings of the two receiving coils 16A and 16B are connected to each other at the end region of the receiving structure 14B, so that the flow direction is reversed in the windings respectively.

[0039] For example, it can also be found from Figure 4 As can be seen, in the third embodiment of the measurement value detection device 10C of the third embodiment of the inductive sensor assembly 1C, the first compensation structure 20C, arranged at the first end of the measurement value detection device 10C, outside the excitation structure 13, and implemented as a planar compensation coil 22, is electrically connected to the first receiving coil 16A of the receiving structure 14B. The second compensation structure 20D, arranged at the second end of the measurement value detection device 10C, outside the excitation structure 13, and implemented as a planar compensation coil 22, is electrically connected to the second receiving coil 16B of the receiving structure 14B. The planar compensation coils 22 of the two compensation structures 20C and 20D each include multiple rectangular windings, and their conductor line sections are constructed only in one plane of the circuit carrier 11. In the third embodiment of the compensation structure 20C shown, the planar compensation coils 22 each include two windings, which are arranged in one plane of the circuit carrier 11. In the second plane of the circuit carrier 11, only conductor line sections are arranged, which electrically connect the ends of the corresponding receiving coils 16A and 16B to the compensation coils 22 of the corresponding compensation structures 20C and 20D through electroplated through-holes DK. In the third embodiment of the measurement value detection device 10C shown, the first compensation structure 20C compensates for the offset value of the first receiving coil 16A, and the second compensation structure 20D compensates for the offset value of the second receiving coil 16B.

[0040] In an alternative embodiment of the measurement value detection device 10 (not shown), compensation structures 20 may be arranged at both ends of the measurement value detection device 10 and electrically connected to one of the receiving coils 16 of the receiving structure 14 to compensate for the offset value of the corresponding receiving coil 16.

Claims

1. A measurement detection device (10) for an inductive sensor assembly (1), the measurement detection device having a circuit carrier (11) having at least one excitation structure (13) and at least one receiving structure (14), wherein, The at least one excitation structure (13) includes at least one excitation coil (13A) having at least one winding, the at least one excitation coil surrounding the at least one receiving structure (14) from both sides, wherein the at least one receiving structure (14) includes at least two receiving coils (16), each of the at least two receiving coils having at least one winding, wherein at least one of the receiving coils (16) is electrically connected to at least one compensation structure (20), the at least one compensation structure being arranged outside the at least one excitation structure (13) and being implemented such that the largest offset voltage among the offset voltages induced by the at least one excitation structure (13) occurring at the at least two receiving coils (16) has a value less than the possible maximum value determined by the construction method.

2. The measuring value detection device (10) according to claim 1, characterized in that, The maximum absolute values ​​of the offset voltages appearing at the two receiving coils (16) of the at least one receiving structure (14) are equal to or equal to zero.

3. The measuring value detection device (10) according to claim 1 or 2, characterized in that, The at least one compensation structure (20) is implemented as a planar compensation coil (22) having at least one winding.

4. The measuring value detection device (10) according to claim 3, characterized in that, The conductor line segments of at least one winding of the at least one compensation structure (20) are constructed in one or at least two planes of the circuit carrier (11), wherein the conductor line segments of the compensation structure (20) arranged in different planes of the circuit carrier (11) are electrically connected to each other through plated through-holes (DK).

5. The measuring value detection device (10) according to claim 3 or 4, characterized in that, The flow direction in the at least one compensation structure (20) is consistent with the flow direction in the corresponding receiving coil (16).

6. The measuring value detection device (10) according to any one of claims 1 to 5, characterized in that, The at least two receiving coils (16) have a predetermined phase shift relative to each other.

7. The measuring value detection device (10) according to any one of claims 1 to 6, characterized in that, At least one winding of the at least two receiving coils (16) has two loop structures (18A, 18B), each loop structure having a plurality of loop segments (SA), and is constructed in at least two planes of the circuit carrier (11), wherein the segments of each loop structure (18A, 18B) arranged in different planes of the circuit carrier (11) are electrically connected to each other through plated through-holes (DK).

8. The measuring value detection device (10) according to claim 7, characterized in that, The two loop structures (18A, 18B) of each winding of the at least two receiving coils (16) have a phase shift of 180° relative to each other and opposite flow directions.

9. The measuring value detection device (10) according to claim 7 or 8, characterized in that, The two loop structures (18A, 18B) of each winding of the at least two receiving coils (16) correspond to a segment (5) with at least one period of mathematical oscillation.

10. The measuring value detection device (10) according to claim 9, characterized in that, The mathematical oscillation has a sinusoidal shape, a rectangular shape, a triangular shape, a trapezoidal shape, or a mixed shape.

11. An inductive sensor assembly (1) for detecting the motion of a movable body, the sensor assembly having at least one coupling device (3) and a measurement value detection device (10) according to any one of claims 1 to 10, wherein, The at least one coupling device (3) or measurement detection device (10) is coupled to a movable body whose movement should be detected, wherein at least one excitation structure (13) is arranged on the circuit carrier (11) of the measurement detection device (10), wherein the at least one excitation structure (13) is coupled to an evaluation and control circuit (12) that couples a periodic alternating signal into the at least one excitation structure (13) during operation, wherein the at least one coupling device (3) is implemented to influence the inductive coupling between the at least one excitation structure (13) of the measurement detection device (10) and at least one receiving structure (14), wherein the at least one evaluation and control unit (12) is implemented to receive and evaluate the signal induced in the at least one receiving structure (14) and determine the current relative position of the movable coupling device (3) with respect to the at least one receiving structure (14) and / or the current position of the movable body.

12. The inductive sensor assembly (1) according to claim 11, characterized in that, The movable body performs rotational or linear motion around a rotation axis.

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