Scanning element and inductive position measuring device with such a scanning element

Abstract

The invention relates to a scanning element and to an inductive position measuring device having the scanning element. The scanning element (1) comprises a circuit board (1.1) which comprises a first detector unit (1.11) having a first receiver conductor path (1.1121) which encircles an axis (R) in a circumferential direction (x). The course of the first receiver conductor path is periodically provided along a first line (K1), the course having a first gap (U1) along its extension in the circumferential direction (x), the course having a first amplitude (J11) in a first quadrant (I) or a second quadrant (II) of a Cartesian coordinate system and a second amplitude (J13) in a third quadrant (III) or a fourth quadrant (IV) of the coordinate system. The origin of the coordinate system is here located on the axis (R) and a longitudinal coordinate (O1) passes centrally through the first gap (U1) with respect to the circumferential direction (x). The second amplitude is smaller than the first amplitude.

Description

Technical Field

[0001] The present invention relates to a scanning element for an inductive position measuring device for determining the position of the scanning element relative to two scale elements that can rotate at different speeds, and the present invention also relates to a position measuring device having such a scanning element. Background Technology

[0002] Inductive position measuring devices are used, for example, as angle measuring devices for determining the angular position of machine parts that can rotate relative to each other. In an inductive position measuring device, exciter and receiver lines are typically mounted, for example, as conductor paths on a common circuit board, primarily multi-layered, which is fixedly connected to the stator of the angle measuring device. A scaling element is provided opposite this circuit board, on which an indexing structure is mounted, and the scaling element is torsionally connected to the rotor of the angle measuring device. If a time-varying excitation current is applied to the exciter lines, a signal dependent on the angular position is generated in the receiver coil during the relative rotation between the rotor and stator. These signals are then further processed in the evaluation electronics.

[0003] Especially in robot drive systems, inductive position measuring devices are commonly used to determine the angular position of the drive shaft and simultaneously to accurately determine the angular position of the output shaft, where the motion of the drive shaft is guided to the output shaft by a reduction gear. In this case, the angular position or angular displacement is measured by means of a scanning element comprising a circuit board having corresponding detector units on both sides, thereby determining the corresponding angular position of a scaling element rotatably arranged on both sides of the circuit board.

[0004] In EP 2 312 272 A2, for example according to Figure 4 there, a position measuring device is shown whose stator has a receiver conductor path having a gap extending in the circumferential direction. Summary of the Invention

[0005] The basic objective of this invention is to provide a scanning element for an inductive position measuring device that operates with relatively high precision and is constructed in a relatively space-saving manner.

[0006] According to the present invention, this objective is achieved as follows.

[0007] A scanning element suitable for and designed for an inductive position measuring device includes a circuit board comprising a first detector unit having at least one first receiver conductor path arranged circumferentially around an axis. The verlauf of the first receiver conductor path is designed to be periodically arranged along a first line. Furthermore, the periodic verlauf of the first receiver conductor path has a first gap along its circumferential extension. To define the geometry and configuration of the receiver conductor path, a Cartesian coordinate system is introduced, configured such that its origin is located on the axis and its ordinate is centered relative to the circumferential direction through the first gap. The verlauf of the first receiver conductor path has a first magnitude in a first or second quadrant of the coordinate system. The verlauf of the first receiver conductor path has a second magnitude in a third or fourth quadrant of the coordinate system. It is also applicable that the second magnitude is less than the first magnitude.

[0008] The first detector unit specifically includes a first receiver line, which in turn includes multiple receiver conductor paths (including the first receiver conductor path), and optionally includes a first actuator line. The first receiver line is arranged around an axis in the circumferential direction.

[0009] The receiver conductor path can extend across two planes or two layers of a circuit board, wherein corresponding portions or segments of such a receiver conductor path are electrically connected to segments in another layer via vias (e.g., in the form of microvias). Due to its periodic orientation, the receiver conductor path has intersections in the plan view. These intersections are points where the receiver conductor paths overlap in their periodic orientation, wherein the receiver conductor paths extend across different layers of the circuit board in the region of the intersection, thus preventing unwanted short circuits from occurring at the intersections.

[0010] The periodic orientation of the first receiver conductor path is designed such that the receiver conductor path encloses a surface between the intersections, which extends along the line, in particular, by a length corresponding to half the period length. The gaps are regions that do not include this enclosing surface. The amplitude can advantageously be limited only to the region of the (especially the first) receiver conductor path, where the orientation of the (especially the first) receiver conductor path is periodic, wherein the (especially the second) amplitude must also be greater than zero. In particular, the region of the first receiver conductor path that does not include the enclosing surface does not have the (especially the second) amplitude.

[0011] Correspondingly, the path of the first receiver conductor, which is arranged circumferentially around the axis on the circuit board, does not extend through the entire 360° in the circumferential direction, but extends through a smaller angle value due to the expansion of the gap.

[0012] Amplitude can be viewed as the maximum spacing between the receiver conductor path and the line within a period length. The formula that gives the receiver conductor path a specific amplitude in the quadrant describes that this amplitude occurs within at least one of several period lengths.

[0013] The first line can be understood as a line formed by connecting the intersections of the paths of the first receiver conductor, or as a line on which the intersections lie. The first line can, in particular, be designed as a circle, with its midpoint thus located on the axis.

[0014] The first receiver conductor path advantageously has a periodic orientation with a constant first period length (λ1) outside the first gap. In particular, the first receiver conductor path thus always extends in the circumferential direction with the same first period length (λ1), while the amplitude changes.

[0015] In another embodiment of the invention, the path of the first receiver conductor has a first amplitude in both the first and second quadrants. Optionally or additionally, the path of the first receiver conductor may have a second amplitude in both the third and fourth quadrants.

[0016] Advantageously, the orientation of the first receiver conductor path has an additional amplitude in the third or fourth quadrant of the coordinate system, wherein the additional amplitude is less than the first amplitude and greater than the second amplitude.

[0017] Advantageously, the first gap extends a first length L1 in the circumferential direction, wherein the first length L1 is the same as or a multiple of the first period length (λ1). (L1 = n·λ1, where n is a natural number greater than zero). Particularly advantageously, the first gap extends a first length L1 in the circumferential direction, wherein the first length L1 is the same as half of the first period length (λ1) or a multiple of half the first period length (λ1). (L1 = n·1 / 2·λ1, where n is a natural number greater than zero.)

[0018] Circuit boards advantageously include electronic components.

[0019] In another embodiment of the invention, the circuit board includes a second detector unit having a second receiver conductor path. The second receiver conductor path is also arranged around an axis in the circumferential direction and has a periodic orientation along a second line. The second detector unit specifically includes a second receiver line, which in turn includes a plurality of receiver conductor paths (including the second receiver conductor path), and optionally includes a second actuator line. The second receiver line is arranged around an axis in the circumferential direction.

[0020] The second line can also be understood as a line formed by connecting the intersections of the conductor paths of the second receiver, or a line on which the intersections are located. The second line can, in particular, be designed as a circle. The midpoint of the second line can, in particular, be located on the axis.

[0021] Furthermore, the path of the second receiver conductor is designed such that it has a third amplitude in the first or second quadrant of another Cartesian coordinate system, and a fourth amplitude in the third or fourth quadrant of that coordinate system. If the origin of the other coordinate system lies on the axis and the ordinate of the other coordinate system passes centrally through the second gap, then the third amplitude is greater than the fourth amplitude.

[0022] The circuit board has a geometric central plane, which is advantageously located between the first detector unit and the second detector unit.

[0023] The two largest (upper) surfaces or sides of the circuit board are usually parallel to each other. The central plane is specifically arranged in the middle between these circuit board surfaces that are parallel to the central plane, so that, especially in the direction z orthogonal to the central plane, the distance from one surface or side of the circuit board to the central plane is the same as the distance from the other surface or side of the circuit board to the central plane.

[0024] In an advantageous embodiment of the invention, the second detector unit and at least one electronic component are arranged on the same side of the circuit board. In this configuration, the second detector unit and the electronic component are offset relative to the central plane in the same direction, such that the central plane is not positioned between the second detector unit and the electronic component.

[0025] Advantageously, the first detector unit has a third receiver line, and the second detector unit has a fourth receiver line. In another embodiment of the invention, the first detector unit has a third actuator line, and the second detector unit has a fourth actuator line.

[0026] In another design of the present invention, the first exciter line and the second exciter line extend in the circumferential direction.

[0027] The first receiver line and the second receiver line extend advantageously in the circumferential direction, as do the first exciter line and the second exciter line.

[0028] The scanning element is advantageously designed to electrically connect the first exciter line and the second exciter line in series.

[0029] The first and second actuator circuits can advantageously be energized by an excitation current, which typically has a time-varying current intensity (alternating or mixed current). The excitation current can be generated electronically, meaning its direction can be shaped electronically. Since there is a physical relationship between current intensity and voltage intensity, the same consideration can naturally be made for the excitation voltage.

[0030] In another embodiment of the invention, the signals generated by the first receiver line and the second receiver line can be further processed by means of electronic components, which in particular form an evaluation circuit.

[0031] Therefore, electronic components can be elements of different electronic circuits or assigned to different circuits. For example, some electronic components can be elements of a circuit used to generate excitation current, or other electronic components can be elements of another circuit used to evaluate or further process signals.

[0032] According to another aspect, the invention also includes an inductive position measuring device having a scanning element and a first scaling element, wherein the first scaling element is arranged spaced apart from the circuit board by an offset parallel to the axis.

[0033] In another embodiment of the invention, the first scaling element has a scale line designed to be circular and arranged concentrically with respect to an axis. The scale line includes a scale structure formed by a periodic sequence of alternating conductive and non-conductive scale regions.

[0034] Advantageously, the position measuring device has a second scaling element. The scaling elements are arranged spaced apart on both sides of the circuit board in the z-direction (orthogonal to the central plane).

[0035] Advantageously, the first scaling element has a first diameter D1, and the second scaling element has a second diameter d2, wherein the first diameter D1 is greater than the second diameter d2 (D1>d2).

[0036] Furthermore, the scaling elements can be rotatably arranged relative to the scanning elements around a common axis.

[0037] Furthermore, at least one of the electronic components may be arranged at a greater distance from the axis than the outer contour of the second scaling element. Then, at least one electronic component is arranged radially outside the second scaling element.

[0038] Further details and advantages of the scanning element according to the invention are given in the following description of embodiments with reference to the accompanying drawings. Attached Figure Description

[0039] Figure 1It is a perspective view of a position measuring device including a scanning element, a first scaling element, and a second scaling element.

[0040] Figure 2 This is a plan view of the first side of the scanning element.

[0041] Figure 3 This is a detailed view of the first side of the scanned element.

[0042] Figure 4 This is a plan view of the second side of the scanning element.

[0043] Figure 5 This is a detailed view of the second side of the scanned element.

[0044] Figure 6 This is a schematic diagram of the first receiver conductor path on the first side of the scanning element.

[0045] Figure 7 This is a schematic diagram of the second receiver conductor path on the second side of the scanning element.

[0046] Figure 8 This is a plan view of the first scaling element.

[0047] Figure 9 This is a planar diagram of the second scaling element. Detailed Implementation

[0048] according to Figure 1 The invention is described using a position measuring device with a scanning element 1, which can be used to detect the angular position of both a first scaling element 2 and a second scaling element 3. Both scaling elements 2 and 3 are rotatably arranged about an axis R relative to the scanning element 1. This position measuring device can be used, for example, in a robot drive mechanism. The second scaling element 3 is then torsionally connected, for example, to a drive shaft of a motor. The drive shaft is in turn connected to a reduction gear with an output shaft. The first scaling element 2 rotates with this output shaft. In this way, for example, an angular position for motor commutation can be set by means of the second scaling element 3, and a relatively high-precision angular position for robot positioning can be set by means of the first scaling element 2.

[0049] The scanning element 1 includes a multi-layered circuit board 1.1 and an electronic component 1.2 mounted on the circuit board 1.1. The scanning element 1 is used to scan a first scaling element 2 and simultaneously scan a second scaling element 3. In this embodiment, the electronic component 1.2 is mounted only on the second side. Optionally or additionally, the first side of the circuit board 1.1 may also be equipped with the electronic component.

[0050] To determine the angle information, a first detector unit 1.11 is arranged on a first side of circuit board 1.1, and a second detector unit 1.12 is arranged on a second side of circuit board 1.1. Figure 1 In the diagram, only the structure of the second detector unit 1.12 located on the outer layer of the circuit board 1.1 can be seen schematically.

[0051] Conversely, in addition Figure 2 and Figure 3 middle( Figure 3 It is based on Figure 2 The enlarged detail view of the first detector unit 1.11 shows its structure in the outer layer and the inner layer of the circuit board 1.1. The first detector unit 1.11 includes a first actuator line 1.111, a first receiver line 1.112, a third actuator line 1.113, a third receiver line 1.114, and a fifth actuator line 1.115. The first receiver line 1.112 includes a first receiver conductor path 1.1121.

[0052] exist Figure 4 and Figure 5 In the diagram, circuit board 1.1 is shown from the other side so that the second detector unit 1.12 is visible. Figure 5 A magnified detail of the second detector unit 1.12 is shown. Figure 4 and Figure 5 The structure of a second detector unit 1.12 located in the outer layer of circuit board 1.1 and another inner layer of the adjacent circuit board 1.1 is also shown. The second detector unit 1.12 includes a second actuator line 1.121, a second receiver line 1.122, a fourth actuator line 1.123, a fourth receiver line 1.124, and a sixth actuator line 1.125. The second receiver line 1.122 includes a second receiver conductor path 1.1221.

[0053] From a geometric point of view, a so-called central plane M can be defined for circuit board 1.1. Figure 1 The central plane is arranged in the center between the first and second sides of the circuit board 1.1, either parallel to the first side or parallel to the second side. The axis R extends perpendicular to the central plane M. The circuit board 1.1 is designed such that the geometric central plane M is located between the first detector unit 1.11 and the second detector unit 1.12.

[0054] The actuator lines 1.111, 1.113, and 1.115 of the first detector unit 1.11 include excitation conductor paths 1.1111, 1.1131, and 1.1151, while the actuator lines 1.121, 1.123, and 1.125 of the second detector unit 1.12 include excitation conductor paths 1.1211, 1.1131, and 1.1251.

[0055] The exciter lines 1.111, 1.113, and 1.115 of the first detector unit 1.11 surround the first receiver line 1.112 and the third receiver line 1.114.

[0056] The exciter lines 1.121, 1.123, and 1.125 of the second detector unit 1.12 surround the second receiver line 1.122 and the fourth receiver line 1.124. The exciter lines 1.111, 1.113, 1.115, 1.121, 1.123, and 1.125 and the receiver lines 1.112, 1.114, 1.122, and 1.124 all extend in the circumferential direction x.

[0057] In this embodiment, each of the receiver lines 1.112, 1.114, 1.122, and 1.124 includes receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.1241, which are staggered in the circumferential direction x, such that they can provide four phase-shift signals corresponding to the bias. In the figures, those receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.124 belonging to the same receiver line 1.112, 1.114, 1.122, and 1.124 are given only one reference numeral. Therefore, for example, all receiver conductor paths 1.1121 of the first receiver line 1.112 have only one reference numeral. Furthermore, the first receiver conductor path 1.1121 of the first detector unit 1.11 is connected to a via in a different layer of the circuit board 1.1, thereby avoiding unwanted short circuits at intersections N1 and N2 (see Figure 1). Figure 6 and Figure 7 This also applies to the receiver conductor paths 1.1221 and 1.1241 of the second detector unit 1.12. Although, strictly speaking, each of the first and second receiver conductor paths 1.1121 and 1.1221 consists of a number of conductor segments, each distributed on two planes or layers and connected in series, this structure is collectively referred to below as receiver conductor paths 1.1221 and 1.1241.

[0058] The first and second receiver conductor paths 1.1121 and 1.1221 are along the first circular line K1 and the second circular line K2. Figure 6 , Figure 7The first line (K1) exhibits a periodic spatial orientation, essentially sinusoidal or sinusoidal in shape. Lines K1 and K2 can be considered as forming circular abscissas relative to the receiver conductor paths 1.1121 and 1.1221. Furthermore, the midpoints of the circular lines K1 and K2 lie on the axis R. Additionally, the first line K1 can be viewed as a line connecting adjacent first intersection points N1. Similarly, the second line K2 can be defined as a line connecting adjacent second intersection points N2. All first intersection points N1 lie on the circular first line K1, and all second intersection points N2 lie on the circular second line K2.

[0059] The receiver conductor path 1.1121 of the first receiver line 1.112 has a period length λ1 ( Figure 3 The receiver conductor path 1.1221 of the second receiver line 1.122 has a period length λ2. Figure 5 In this embodiment, within receiver lines 1.112, 1.114, 1.122, and 1.124, adjacent receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.1241 are staggered from each other by 1 / 8 of a complete sine cycle (π / 4 or 45° along the circumferential direction x), thereby enabling the generation of these corresponding phase-shifted signals. Receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.1241 are electrically connected in such a way that they transmit signals at 0° and 90° on one hand, and signals at 45° and 135° on the other. A first position signal can be determined from the 0° and 90° signals, and a second position signal, redundant with respect to the first position signal, can be determined from the 45° and 135° signals.

[0060] Figure 6 A simplified view of the first receiver conductor path 1.1121 of the first receiver line 1.112 is shown; for clarity, the receiver conductor paths of the first receiver line 1.112 with associated phase shifts are omitted from the illustration. According to Figure 6 The first receiver conductor path 1.1121 extends along its circumferential direction x with a first gap U1, which belongs to the same phase or provides a signal for a phase. The region of the first gap U1 is therefore limited by the first receiver conductor path 1.1121 of the phase. There is no periodically extending first receiver conductor path 1.1121 of the associated phase in the region of the first gap U1.

[0061] Based on the first period length λ1, and... Figure 6 The receiver conductor path 1.1121 belonging to the same phase can be divided into 15 sectors of equal size 1a to 1o, each sector extending 24° at its central angle. According to... Figure 6In the presented embodiment, the first gap U1 extends along a first length L1 according to an angle, which corresponds to a first period length λ1 or 24°, where: L1 = λ1 = 24°. To explain the geometric arrangement, a Cartesian coordinate system can be introduced first, arranged such that its origin is located on the axis R or at the midpoint of the first line K1, while the ordinate O1 extends centrally through the first gap U1. The ordinate O1 therefore has the same distance in the circumferential direction x from the end of the periodically extending first receiver conductor path 1.1121. According to the usual division, the coordinate system has four quadrants I to IV. The direction of the first receiver conductor path 1.1121 has different amplitudes J11, J12, J13 along the circumferential direction x. Therefore, in the region of maximum deflection, there are different distances between the first line K1 and the sinusoidally extending receiver conductor path 1.1121. In this embodiment, the following amplitudes J11, J12, J13 can be determined for each sector 1a to 1o:

[0062] Amplitude J11 (100%): Sectors 1a, 1b, 1c, 1d, 1f, 1g, 1h, 1i, 1j, 1o

[0063] Amplitude J12 (80%): Sector 1k, 1n

[0064] Amplitude J13 (70%): Sector 11, 1m

[0065] No amplitude: Sector 1e (the area of ​​the first gap U1).

[0066] The first receiver conductor path 1.1121 therefore has a first amplitude J11 in the first quadrant I and the second quadrant II. Furthermore, the first receiver conductor path 1.1121 has a second amplitude J13, which is smaller than the first amplitude J11, in the third quadrant III and the fourth quadrant IV.

[0067] Furthermore, the path of the first receiver conductor 1.1121 has another amplitude J12 in the third quadrant III and the fourth quadrant IV of the coordinate system, which is smaller than the first amplitude J11 and larger than the second amplitude J13. Therefore, J11>J12>J13.

[0068] exist Figure 7 A simplified view of the second receiver conductor path 1.1221 of the second receiver line 1.122 is shown here and in Figure 6 The receiver conductor path associated with this phase shift is omitted.

[0069] according to Figure 7The second receiver conductor path 1.1221, belonging to the same phase, extends along its circumferential direction x with a second gap U2. The region of the second gap U2 is therefore limited by the second receiver conductor path 1.1221. There is no second receiver conductor path 1.1221 with a periodic orientation of the corresponding phase within the region of the second gap U2. Based on the second period length λ2, belonging to... Figure 6 The receiver conductor path 1.1221 in the phase can be divided into 16 equally sized sectors 2a to 2p, each sector extending at a central angle of 22.5°. According to... Figure 7 In the presented embodiment, the second gap U2 extends along a second length L2 according to an angle, which corresponds to twice the second period length λ2, i.e., 45°. Therefore: L2 = 2·λ2 = 2·22.5°. In the second receiver line 1.122, the direction of the second receiver conductor path 1.1221 also has different amplitudes J21, J22, J23, J24 along the circumferential direction x. In this embodiment, the following amplitudes J21, J22, J23, J24 can be determined for each sector 2a to 2p:

[0070] Amplitude J21 (100%): Sectors 2a, 2b, 2c, 2f, 2g, 2h, 2i, 2p

[0071] Amplitude J22 (80%): Sector 2j, 2o

[0072] Amplitude J23: (65%) Sector 2k, 2n

[0073] Amplitude J24 (50%): Sector 21, 2m

[0074] No amplitude: sector 2d, 2e (within the area of ​​the second gap U2).

[0075] Therefore, the second receiver conductor path 1.1221 has a third amplitude J21 in the first quadrant I and the second quadrant II. Furthermore, the second receiver conductor path 1.1221 has a fourth amplitude J24 in the third quadrant III and the fourth quadrant IV, which is smaller than the third amplitude J21.

[0076] The orientation of the second receiver conductor path 1.1221 is designed such that the transition from the maximum third amplitude J21 to the minimum fourth amplitude J24 is achieved in a stepped manner. Correspondingly, the orientation of the second receiver conductor path 1.1221 has two additional amplitudes J22 and J23 in the third quadrant III and fourth quadrant IV of the coordinate system, which are smaller than the third amplitude J21 and larger than the fourth amplitude J24. Therefore, J21 > J22 > J23 > J24.

[0077] In addition, circuit board 1.1 has through holes 1.15 and 1.16 ( Figure 3 and Figure 5 Circuit board 1.1 is designed such that through-holes 1.15 and 1.16 are arranged within the first gap U1 and the second gap U2. Through through-hole 1.15, the first receiver conductor path 1.1121 of the first receiver line 1.112 is electrically connected to the electronic component 1.2 arranged on the other side of the central plane M. This special design of the routing of the first and second receiver conductor paths 1.1121 and 1.1221 with gaps U1 and U2 enables a particularly space-saving design for circuit board 1.1. The signal insufficiency caused by gaps U1 and U2 can be compensated for by the ingenious design of the routing of the first and second receiver conductor paths 1.1121 and 1.1221, ultimately achieving a space-saving design and accurate angle measurement.

[0078] exist Figure 8 In the diagram, the first scaling element 2 is shown in a plan view. The second scaling element 3 is also shown in the plan view. Figure 9 The diagram is shown in plan view. Scale elements 2 and 3 have a disk-like shape, wherein the first scale element 2 has a first diameter D1 and the second scale element 3 has a second diameter d2. The first diameter D1 is greater than the second diameter d2 (D1>d2).

[0079] Scale elements 2 and 3 are each composed of a substrate, which, in the illustrated embodiment, is made of epoxy resin, and two indexing lines 2.1, 2.2; 3.1, 3.2 are arranged on each substrate. The indexing lines 2.1, 2.2; 3.1, 3.2 are designed in a ring shape and concentrically arranged on the substrate with different diameters relative to the axis R. Each indexing line 2.1, 2.2; 3.1, 3.2 has an indexing structure, which is formed by a periodic sequence of conductive indexing regions 2.11, 2.21; 3.11, 3.21 and non-conductive indexing regions 2.12, 2.22; 3.12, 3.22. In the illustrated example, copper is applied to the substrate as the material for the conductive indexing regions 2.11, 2.21; 3.11, 3.21. However, the substrate is uncoated in the non-conductive indexing regions 2.12, 2.22; 3.12, 3.22. Since there are two scaled regions 2.1, 2.2; 3.1, 3.2, the angular positions of scaled elements 2 and 3 can be absolutely determined. The outermost scaled line 2.2 of the first scaled element 2 has the largest number of scaled regions 2.21, 2.22 along the circumference, thereby achieving the maximum resolution for angular position measurement.

[0080] According to Figure 1In the assembled state, scanning element 1 and scale elements 2 and 3 are positioned opposite each other with an axial spacing or air gap, so that when relative rotation occurs between scale elements 2 and 3, scanning element 1 in the receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.1241 can generate signals related to each angular position through induction effects. A prerequisite for forming the corresponding signals is that the excitation conductor paths 1.1111, 1.1131, 1.1151, 1.1211, 1.1231, and 1.1251 generate time-varying electromagnetic excitation fields within the regions of their respective scanning indexing structures. In the illustrated embodiment, the excitation conductor paths 1.1111, 1.1131, 1.1151, 1.1211, 1.1231, and 1.1251 are designed as multiple planar parallel, current-carrying individual conductor paths. Scanning element 1 has an electronic circuit with electronic components 1.2. For example, the electronic circuit may also include an ASIC (Application-Specific Integrated Circuit) module. This electronic circuit of scanning element 1 serves not only as an evaluation element but also as an excitation control element, generating an excitation current under its control, which then flows through excitation conductor paths 1.1111, 1.1131, 1.1151, 1.1211, 1.1231, and 1.1251. Excitation conductor paths 1.1111, 1.1131, 1.1151, 1.1211, 1.1231, and 1.1251 are therefore energized by the same excitation control element. The first exciter line 1.111 and the second exciter line 1.121 are electrically connected in series.

[0081] If exciter lines 1.111, 1.113, 1.115, 1.121, 1.123, and 1.125 are energized, tubular or cylindrical electromagnetic fields are formed around the excitation conductor paths 1.1111, 1.1131, 1.1151, 1.123, and 1.1125. The field lines of the generated electromagnetic field surround the exciter lines 1.111, 1.113, 1.115, 1.121, 1.123, and 1.125, and the direction of the field lines depends in a known manner on the direction of the current in the excitation conductor paths 1.1111, 1.1131, 1.1151, 1.1211, 1.1231, and 1.1251. Eddy currents are generated in the conductive index regions 2.11, 2.21; 3.11, and 3.21, thereby enabling field modulation that depends on the angular position. Accordingly, in each case, the relative angular position can be measured via receiver lines 1.112, 1.114, 1.122, and 1.124. The pairs of receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.1241 are arranged within their receiver conductor paths 1.112, 1.114, 1.122, and 1.124 such that they each provide signals 90° out of phase so that the direction of rotation can be determined. The signals generated by receiver lines 1.112, 1.114, 1.122, and 1.124 are further processed by means of some electronic components 1.2 forming the evaluation circuit.

[0082] The advantage of high measurement accuracy and relatively large permissible installation tolerances lies in the so-called omnidirectional scanning. In omnidirectional scanning, scale elements 2 and 3 are scanned as a whole at any point in time, that is, scanned virtually across the entire circumference. This is beneficial for compensating for wobbling errors or eccentricities that may occur in the measurement results. Even if the receiver conductor paths 1.1121 and 1.1221 have gaps U1 and U2, the novel scanning element 1 can achieve accurate measurements.

Claims

1. A scanning element (1) for use in a sensing position measuring device, the scanning element comprising a circuit board (1.1), the circuit board comprising... A first detector unit (1.11) includes a first receiver conductor path (1.1121) arranged around an axis (R) in the circumferential direction (x). The direction of the first receiver conductor path (1.1121) Periodically set along the first line (K1), The extension of the orientation along the circumferential direction (x) has a first gap (U1). The orientation has a first magnitude (J11) in the first quadrant (I) or the second quadrant (II) of the Cartesian coordinate system, and The orientation has a second magnitude (J13) in the third quadrant (III) or fourth quadrant (IV) of the coordinate system, wherein, The origin of the coordinate system is located on the axis (R), and the ordinate (O1) extends centrally through the first gap (U1) relative to the circumferential direction (x). The second amplitude (J13) is smaller than the first amplitude (J11).

2. The scanning element (1) according to claim 1, wherein, The first line (K1) is set to be circular.

3. The scanning element (1) according to claim 1 or 2, wherein, The first receiver conductor path (1.1121) has a periodic orientation with a constant first period length.

4. The scanning element (1) according to claim 1 or 2, wherein, The first receiver conductor path (1.1121) has the first amplitude (J11) in the first quadrant (I) and the second quadrant (II).

5. The scanning element (1) according to claim 4, wherein, The first receiver conductor path (1.1121) also has the second amplitude (J13) in the third quadrant (III) and the fourth quadrant (IV).

6. The scanning element (1) according to claim 1 or 2, wherein, The first receiver conductor path (1.1121) has an additional amplitude (J12) in the third quadrant (III) or the fourth quadrant (IV) of the coordinate system, wherein the additional amplitude (J12) is less than the first amplitude (J11) and greater than the second amplitude (J13).

7. The scanning element (1) according to claim 3, wherein, The first gap (U1) extends a first length L1 in the circumferential direction (x), wherein the first length L1 is half of the first period length λ1 or equal to a multiple of half of the first period length, i.e., L1=n·1 / 2·λ1, where n is a natural number greater than zero.

8. The scanning element (1) according to claim 1 or 2, wherein, The circuit board (1.1) includes electronic components (1.2).

9. The scanning element (1) according to claim 1 or 2, wherein, The circuit board (1.1) includes a second detector unit (1.12) having a second receiver conductor path (1.1221) arranged around the axis (R) in the circumferential direction (x), wherein, The direction of the second receiver conductor path (1.1221) It is set periodically along the second line (K2). The second receiver conductor path extends along the circumferential direction (x) with a second gap (U2). The path of the second receiver conductor has a third amplitude (J21) in either the first quadrant (I) or the second quadrant (II) of another Cartesian coordinate system, and The path of the second receiver conductor has a fourth amplitude (J24) in the third (III) or fourth (IV) quadrant of the additional Cartesian coordinate system, wherein, The origin of the additional Cartesian coordinate system is located on the axis (R), and the ordinate (O2) of the additional Cartesian coordinate system extends centrally through the second gap (U2). The fourth amplitude (J24) is smaller than the third amplitude (J21).

10. The scanning element (1) according to claim 9, wherein, The second receiver conductor path (1.1221) has a periodic orientation with a constant second period length λ2, and the second gap (U2) extends a second length L2 in the circumferential direction (x), wherein the second length L2 is half of the second period length λ2 or equal to a multiple of half the second period length, i.e., L2=n·½·λ2, where n is a natural number greater than zero.

11. The scanning element (1) according to claim 1 or 2, wherein, The circuit board (1.1) includes a second detector unit (1.12), the second detector unit including a second receiver conductor path (1.1221), the second receiver conductor path being arranged around the axis (R) in the circumferential direction (x), wherein the circuit board (1.1) has a geometric central plane (M) located between the first detector unit (1.11) and the second detector unit (1.12).

12. An inductive position measuring device, comprising a scanning element (1) according to any one of claims 1 to 11 and a first scaling element (2), wherein, The first scaling element (2) is arranged at an offset parallel to the axis (R) from the circuit board (1.1).

13. The inductive position measuring device according to claim 12, wherein, The first scaling element (2) has a scaling line (2.1) designed to be circular and arranged concentrically with respect to the axis (R), wherein the scaling line (2.1) includes a scaling structure formed by a periodic sequence of alternating conductive scaling regions (2.11) and non-conductive scaling regions (2.12).

14. The inductive position measuring device according to claim 12 or 13, wherein, The position measuring device has a second scaling element (3), wherein the first scaling element (2) and the second scaling element (3) are arranged on opposite sides of the circuit board (1.1) in a direction (z) orthogonal to the geometric central plane orientation.

15. The inductive position measuring device according to claim 14, wherein, The first scaling element (2) has a first diameter (D1), and the second scaling element (3) has a second diameter (d2), and the first diameter (D1) is larger than the second diameter (d2).

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