Scanning element and inductive position measuring device having 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 multilayer circuit board (1.1) and an electronic assembly (1.2), the circuit board comprising a first detector unit (1.11) with a first receiver line (1.112) and a second detector unit (1.12) with a second receiver line (1.122). The circuit board has a geometric central plane (M) between the detector units (1.11, 1.12). The receiver lines (1.112, 1.122) comprise first and second receiver conductor paths (1.1121, 1.1221) each having a periodic course, the first receiver line (1.112) having a first gap (U1) delimited by the first receiver conductor path (1.1121) along which it extends. The second receiver line (1.122) has a second gap (U2) delimited by the second receiver conductor path (1.1221). The circuit board has a through-hole (1.15) arranged in the first gap and in the second gap.

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 JP 2006208239 A, a position measuring device having two rotors is disclosed, specifically according to Figure 6 therein. A stator is provided between the rotors. The position measuring device described therein is used, for example, in a micron bolt. 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 relatively accurately and can be manufactured compactly and at low cost, enabling the determination of the position or angular orientation of two scale elements.

[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 multilayer circuit board with a first detector unit and a second detector unit, as well as electronic components. The first detector unit has a first actuator line and a first receiver line and is arranged in the first and second layers of the circuit board. The second detector unit has a second actuator line and a second receiver line and is arranged in the third and fourth layers of the circuit board. The circuit board has a geometrically central plane between the detector units, wherein the first and second receiver lines are arranged circumferentially around an axis. The first receiver line includes a first receiver conductor path, and the second receiver line includes a second receiver conductor path. These receiver lines each have a periodic vertices. The first receiver line has a first gap along its extension direction, the first gap being defined circumferentially by the first receiver conductor path. The second receiver line has a second gap along its extension direction, the second gap being defined circumferentially by the second receiver conductor path. The circuit board has through-holes arranged not only within the first gap but also within the second gap. Specifically, the through-holes are arranged correspondingly between the first and second receiver conductor paths relative to the axial direction.

[0008] In determining the spatial arrangement of the contents of this invention, a first direction x can be defined first. The first direction x represents the direction in which the sought position (measurement direction) is measured. Since the position measuring device should measure the first relative angular position between the first scaling element and the scanning element in terms of rotation and oscillation motion about the (rotational) axis, and simultaneously measure the second angular position between the second scaling element and the scanning element, the first direction x is either a circumferential direction or a tangential direction.

[0009] Furthermore, it is possible to define a second direction y, which extends perpendicularly to the first direction x.

[0010] A third direction z is positioned perpendicular to the first direction x and simultaneously perpendicular to the second direction y. The third direction z extends parallel to the (rotational) axis, around which the scaling element can rotate relative to the scanning element. Furthermore, the third direction z is oriented perpendicular to the central plane. The various positions on the circuit board are staggered relative to each other along the third direction z.

[0011] Specifically, the end, i.e., the contact of the through hole, is arranged within the first gap, and the other end or other contact is arranged within the second gap. Specifically, the through hole can extend in the third direction z.

[0012] The two largest faces of the circuit board are typically positioned parallel to each other. In particular, a central plane is arranged parallel to these faces between the planes of the circuit board, such that, especially in the third direction z, the distance between the faces of the circuit board and the central plane is exactly equal to the distance between the other faces of the circuit board and the central plane.

[0013] In another design of the present invention, the first actuator line and the second actuator line extend along the circumferential direction or along the first direction x.

[0014] The first receiver line and the second receiver line are advantageously extended along the circumferential direction or along the first direction x, like the first actuator line and the second actuator line.

[0015] The scanning element is advantageously designed to electrically connect the first exciter line and the second exciter line in series.

[0016] The first and second actuator circuits can advantageously be supplied with excitation current, which typically has alternating current intensities (alternating current or mixed current) over time. The excitation current can be generated by electronic components, meaning its flow can be shaped by electronic components. Given the physical relationship between current and voltage intensities, the excitation voltage can, of course, also be considered.

[0017] In another embodiment of the invention, the signal generated by the first receiver line and the second receiver line can be further processed by means of electronic components that specifically form the evaluation circuit.

[0018] Therefore, electronic components can be elements of different circuits or belong to different circuits. For example, a particular electronic component can be an element of a circuit used to generate excitation current, or another electronic component can be an element of another circuit used to evaluate or further process signals.

[0019] The circuit board is advantageously designed such that vias electrically connect the first detector unit to a third or fourth layer. Optionally, vias can electrically connect the second detector unit to a first or second layer. In particular, vias can connect to conductor paths located in the corresponding first, second, third, or fourth layer.

[0020] In another embodiment of the invention, the via is electrically connected to one of the electronic components, thereby enabling the electronic components to transmit a specific signal through the via, which is generated by a first detector unit or a second detector unit or its receiver conductor path.

[0021] In an advantageous embodiment of the invention, the through-hole is implemented as a via. Specifically, the through-hole is made by a through-hole that passes through a circuit board. Preferably, the hole has a metal layer, particularly a copper plating, on its inner wall. The upper and lower contacts of the through-hole form electrical contacts with a conductor path, conductor layer, or electronic component. The concept of a through-hole is also understood hereafter as an arrangement in which multiple holes or cavities filled or plated with a conductive material are arranged offset from each other (particularly in the radial or circumferential direction). Such through-holes are often also referred to as staggered holes.

[0022] In another embodiment of the invention, the first gap extends a first length in the circumferential direction, wherein the first receiver conductor path has a periodic orientation with a first period length λ1. Here, the first length is greater than or equal to 1 / 8 of the first period length λ1, i.e., L1 (first period length) ≥ 1 / 8·λ1.

[0023] The scanning element is advantageously designed such that the second gap extends a second length in the circumferential direction, and the second receiver conductor path has a periodic orientation with a second period length λ2. In this case, the second length is greater than or equal to 1 / 8 of the second period length λ2, i.e., L2 (second period length) ≥ 1 / 8·λ2.

[0024] In another embodiment of the invention, the first receiver conductor path has a periodic orientation with a first period length λ1, and the second receiver conductor path has a periodic orientation with a second period length λ2. The second period length λ2 is greater than or equal to the first period length λ1 (λ2 ≥ λ1).

[0025] In an advantageous embodiment of the invention, at least one of the second detector unit and the electronic component is arranged on the same side of the circuit board. Therefore, in this structure, the second detector unit and the electronic component are offset relative to the central plane in the same direction, so that the central plane is not positioned between the second detector unit and the electronic component.

[0026] Advantageously, the first detector unit has a third receiver line and the second detector unit has a fourth receiver line. Specifically, the third receiver line can then include a third receiver conductor path, wherein the third receiver conductor path has a periodic orientation, and the period length of the third receiver conductor path is less than the first period length λ1 of the first receiver conductor path. Furthermore, the fourth receiver line can include a fourth receiver conductor path, wherein the fourth receiver conductor path has a periodic orientation, and the period length of the fourth receiver conductor path is greater than the second period length λ2 of the second receiver conductor path.

[0027] In another design of the present invention, the first detector unit has a third exciter line and the second detector unit has a fourth exciter line.

[0028] In a favorable design, the first shielding layer is disposed on the fifth layer of the circuit board, and the second shielding layer is disposed on the sixth layer of the circuit board, wherein vias pass through the first and second shielding layers, and in particular, do not make electrical contact with the shielding layers. A central plane is positioned between the first and second shielding layers, thus allowing the shielding layers to be disposed on both sides of the central plane.

[0029] The central plane, relative to a third direction z, is located between the first detector unit and the first shielding layer. Similarly, the central plane, relative to a third direction z, is located between the second detector and the second shielding layer, or the second detector and the second shielding layer are arranged on either side of the central plane.

[0030] According to another aspect, the invention also includes an inductive position measuring device having a scanning element and a first scaling element and a second scaling element. The scaling elements are arranged spaced apart on both sides of the circuit board in a third direction z (orthogonal to the central plane).

[0031] Advantageously, the first engraving 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).

[0032] Furthermore, the scaling elements can be arranged around a common axis relative to the scanning elements.

[0033] Furthermore, at least one electronic component is arranged further away from the axis than the outer contour of the second scaling element. Therefore, at least one electronic component is arranged radially outside the second scaling element.

[0034] Further details and advantages of the scanning element according to the invention will become apparent from the following description of embodiments according to the accompanying drawings. Attached Figure Description

[0035] Figure 1 It is a perspective view of a position measuring device including a scanning element, a first scaling element, and a second scaling element.

[0036] Figure 2 This is a plan view of the first side of the scanning element.

[0037] Figure 3 This is a detailed view of the first side of the scanned element.

[0038] Figure 4 This is a plan view of the second side of the scanning element.

[0039] Figure 5 This is a detailed view of the second side of the scanned element.

[0040] Figure 6 This is a detailed partial view of the line PP of the scanned element.

[0041] Figure 7 It is a detailed partial view of the element through the via area.

[0042] Figure 8 This is a plan view of the first scaling element.

[0043] Figure 9 This is a planar diagram of the second scaling element. Detailed Implementation

[0044] This invention is based on Figure 1 The position measuring device is described, comprising a scanning device 1 capable of detecting not only the angular position of a first scaling element 2, but also the angular position of a second scaling element 3. The two scaling elements 2 and 3 are arranged around an axis R relative to the scanning element 1. This position measuring device can be applied, for example, in a rotor drive mechanism. Subsequently, the second scaling element 3 is torsionally connected, for example, to the drive shaft of an engine. The drive shaft is in turn connected to a reduction gear with a transmission shaft. The first scaling element 2 rotates using this transmission shaft. In this manner, for example, the angular position for engine reversal can be set by means of the second scaling element 3, and a relatively high-precision angular position for positioning the robot can be set by means of the first scaling element 2.

[0045] 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 to scan a second scaling element 3. In the illustrated embodiment, the electronic component 1.2 is mounted only on the second side. However, optionally or additionally, the electronic component can also be mounted on the first side of the circuit board 1.1.

[0046] To determine the angle information, a first detector unit 1.11 is arranged on the first side of the circuit board 1.1, and a second detector unit 1.12 is arranged on the second side of the circuit board 1.1. Figure 1 Only the second detector unit 1.12 is seen in this structure, which is located on the outer fourth layer F (see...). Figure 6 and Figure 7 ).

[0047] On the other hand, Figure 2 and Figure 3 ( Figure 3 It is based on Figure 2 The enlarged detail view of the first detector unit 1.11 shows this structure, which is located in a first layer A outside the circuit board 1.1 and in a second layer B 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.

[0048] Figure 4 and Figure 5 The other side of the circuit board 1.1 is shown so that the second detector unit 1.12 is visible. Figure 5 A magnified detail of the second detector unit 1.12 is shown. On the other hand, in Figure 4 and Figure 5 The diagram illustrates this structure of the second detector unit 1.12, which is located in the fourth layer F outside the circuit board 1 and in the third layer E of the circuit board. 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.

[0049] Figure 6 A schematic partial cross-sectional view is shown based on the cut line PP of scanning element 1 or circuit board 1.1, wherein the shaded lines of the electrical insulation material of circuit board 1.1 are omitted for simplicity. Furthermore, Figure 6 The partial cross-sectional view is provided to better illustrate the scanning element 1 according to the invention, rather than being designed to scale. The circuit board 1.1 is constructed in multiple layers as mentioned above. Geometrically, it is noted that a so-called central plane M can be defined for the circuit board 1.1, which is arranged parallel to or parallel to a first side of the circuit board 1.1, between the first and second sides. Furthermore, the geometric relationships of the various elements can be defined mutually by means of a coordinate system. Here, the first direction x is the direction along which position or angle is typically measured. In the current embodiment, the first direction x corresponds to the circumferential direction. The axis of rotation R around which the scaling elements 2 and 3 can be extended parallel to a third direction z, which can also be defined here as an axial direction. The second direction y, also referred to as the radial direction, is positioned perpendicular to the third direction z and the first direction x. Thus, the plane unfolded by the x and y axes is oriented parallel to the central plane M, and the third direction z and the axis R extend perpendicular to the central plane M.

[0050] A first detector unit 1.11 is arranged in the first layer A and the second layer B of circuit board 1.1, while a second detector unit 1.12 is arranged in the third layer E and the fourth layer F. The first layer A is located immediately adjacent to the first side of circuit board 1.1, and the second layer B is located immediately adjacent to the first side of circuit board 1.1. The same applies to the second side of circuit board 1.1 for the fourth layer F and the third layer E.

[0051] 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 extending in the first layer A. Similarly, the actuator lines 1.121, 1.123, and 1.125 of the second detector unit 1.12 include excitation conductor paths 1.1211, 1.1231, and 1.12511 extending in the fourth layer F.

[0052] In addition, circuit board 1.1 also includes a fifth layer D and a sixth layer C. A first shielding layer 1.13 is present in the fifth layer D and a second shielding layer 1.14 is present in the sixth layer C. Shielding layers 1.13 and 1.14 are copper plating layers with relatively large areas.

[0053] The actuator lines 1.111, 1.113, and 1.115 of the first single-sided unit 1.11 surround the first receiver line 1.112 or the third receiver line 1.114.

[0054] The actuator lines 1.121, 1.123, and 1.125 of the second detector unit 1.12 surround the second receiver line 1.122 or the fourth receiver line 1.124. The actuator 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 extend along the circumferential direction or along the first direction x.

[0055] Each of the receiver lines 1.112, 1.114, 1.122, and 1.124 in the current embodiment includes receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.1241, respectively, which are arranged staggered in the circumferential direction, thereby enabling them to provide four phase-shifted signals according to the offset. In the figures, only one or the same receiver lines 1.112, 1.114, 1.122, and 1.124 are labeled with a single reference numeral. Therefore, all receiver conductor paths 1.1121 of, for example, the first receiver line 1.112 are labeled with a single reference numeral. Furthermore, the first receiver conductor path 1.1121 of the first detector unit 1.11 is connected to vias on different layers of the circuit board 1.1, thereby avoiding unwanted short circuits at intersections. The same applies to the receiver conductor paths 1.1221 and 1.1241 of the second detector unit 1.12. Since each of the first and second receiver conductor paths 1.1121 and 1.1221 consists of exactly four conductor blocks distributed in two planes or layers and connected in series, this structure is then collectively labeled as receiver conductor paths 1.1221 and 1.1241.

[0056] Receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.1241 have a spatially periodic orientation and are essentially designed to be sinusoidal. 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 the current embodiment, adjacent receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.1241 within receiver lines 1.112, 1.114, 1.122, and 1.124 are arranged staggered from each other by 1 / 8 of the entire sine cycle (π / 4 or 45° along the circumferential direction or the first direction x). Receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.1241 are electrically connected to provide signals at 0° and 90° on one side and signals at 45° and 135° on the other side. A position signal can be determined from the 0° and 90° signals, and a redundant second position signal related to the first position signal can be determined from the 45° and 135° signals.

[0057] In the current embodiment, the second period length λ2 is greater than the first period length λ1.

[0058] like Figure 2 and Figure 3 As shown, the first receiver line 1.112 has a first gap U1 along its extension in the circumferential direction (x-direction). The region of the first gap U1 is defined by the first receiver conductor path 1.1121, and therefore there is no detector structure between the defined receiver conductor paths 1.1121. Therefore, in a first-order approximation, the first gap U1 is a region geometrically considered as a ring sector. The minimum circumferential spacing L1 between two first receiver conductor paths 1.1121 in the region of the first gap U1 is 5 / 8·λ1 (U1 = 5 / 8·λ1) in the current embodiment. Therefore, periodically extending first receiver conductor paths 1.1121 are not arranged in the region of the first gap U1.

[0059] according to Figure 4 and Figure 5 The second receiver line 1.122 has a second gap U2 along its circumferential extension. This second gap U2 is defined by the second receiver conductor path 1.1221. The minimum circumferential spacing L2 between two second receiver conductor paths 1.1221 in the region of the second gap U2 is 13 / 8 (U1 = 13 / 8·λ1) in the current embodiment. Therefore, no periodically extending second receiver conductor paths 1.1221 are arranged in the region of the second gap U2.

[0060] In addition, circuit board 1.1 has through holes 1.15 and 1.16. Figure 7 A schematic partial cross-sectional view is shown in the region of vias 1.15 and 1.16, through scanning element 1 or through circuit board 1.1. Vias 1.15 and 1.16 are implemented here as vias and subsequently extend through the entire thickness of circuit board 1.1. Therefore, vias 1.15 and 1.16 extend parallel to a third direction z. Circuit board 1.1 is then designed such that vias 1.15 and 1.16 are arranged not only within the first gap U1 but also within the second gap U2.

[0061] 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 this side of the central plane M via through-hole 1.15. For this purpose, a conductor path extending in the second layer B is utilized... Figure 7 An invisible first receiver conductor path 1.1121 establishes an electrical contact to via 1.15. Visor 1.15 passes through a first shielding layer 1.13 and a second shielding layer 1.14, wherein shielding layers 1.13 and 1.14 are structured to prevent electrical connection to via 1.15. Contact is now established in the third layer E to a conductor path extending within layer E. This conductor path is electrically connected to additional vias, here blind vias or microvias, through which a final contact is established to electronic component 1.2.

[0062] The additional via 1.16 connects the first receiver conductor path 1.1121 extending in the first layer A to the fourth layer F. Electrical contact to the electronic component 1.2 is established via a conductor path not visible in the figures.

[0063] The first receiver line 1.112 is arranged overlapping the second receiver line 1.122 in the second direction y.

[0064] Figure 8 A plan view of the first scaling element 2 is shown. The second scaling element 3 is... Figure 9 The diagram also shows a planar view. Scale elements 2 and 3 have a sheet-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).

[0065] Scale elements 2 and 3 are each composed of a substrate, which in the illustrated embodiment is made of epoxy resin and on which two indexing lines 2.1, 2.2; 3.1, 3.2 are respectively arranged. The indexing lines 2.1, 2.2; 3.1, 3.2 are designed to be annular and concentrically arranged on the substrate with different diameters relative to the axis R. The indexing lines 2.1, 2.2; 3.1, 3.2 include an indexing structure formed by a periodic array of alternately arranged 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 used as the material for the conductive indexing regions 2.11, 2.21; 3.11, 3.21 mounted on the substrate. Conversely, the substrate is not plated in the non-conductive indexing regions 2.12, 2.22; 3.12, 3.22. The angular positions of the scale elements 2 and 3 can be absolutely determined by arranging them with two indexing lines 2.1 and 2.2 respectively; 3.1 and 3.2. The outermost indexing line 2.2 of the first scale element 2 has the maximum number of indexing regions 2.21 and 2.22 along the circumferential direction, thereby enabling the maximum resolution for measuring the angular position.

[0066] According to Figure 1In the assembled state, scanning element 1 and scaling elements 2 and 3 are positioned opposite each other with an axial spacing or an air gap, so that when there is relative rotation between scaling elements 2 and 3 and scanning element 1, signals dependent on the corresponding angular positions can be generated in the receiver conductor paths 1.1121, 1.1141, 1.1221, and 1.1241 through induction effects. The 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-alternating electromagnetic excitation fields in the region of the indexing structure of the corresponding scan. In the illustrated embodiment, the excitation conductor paths 1.1111, 1.1131, 1.1151, 1.1211, 1.1231, and 1.1251 are constructed as multiple individual current-carrying conductor paths parallel to each other in a plane. Scanning element 1 has a circuit with electronic components 1.2, which are electrically interconnected via layers E and F. The circuit may also include, for example, an ASIC (Application-Specific Integrated Circuit) module. This circuit of scanning element 1 functions not only as an evaluation element but also as an excitation control element, generating an excitation current under its control. This excitation current then flows through excitation conductor paths 1.1111, 1.1131, 1.1151, 1.1211, 1.1231, and 1.1251. Therefore, excitation conductor paths 1.1111, 1.1131, 1.1151, 1.1211, 1.1231, and 1.1251 are energized through one or the same excitation control element. Here, the first exciter line 1.111 and the second exciter line 1.121 are electrically connected in series.

[0067] If exciter lines 1.111, 1.113, 1.115, 1.121, 1.123, and 1.125 are energized, then a tubular or cylindrical electromagnetic field is formed around the excitation conductor paths 1.1111, 1.1131, 1.1151, 1.1211, 1.1231, and 1.1251. The field lines of the synthesized electromagnetic field extend around the exciter lines 1.111, 1.113, 1.115, 1.121, 1.123, and 1.125, wherein the direction of the field lines depends, in a known manner and type, 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 induced in the conductive graduation regions 2.11, 2.21; 3.11, 3.21, thereby achieving field modulation dependent on angular position. Accordingly, relative angular positions can be measured via receiver lines 1.112, 1.114, 1.122, 1.124. The pairs of receiver conductor paths 1.1121, 1.1141, 1.1221, 1.1241 are arranged within their receiver lines 1.112, 1.114, 1.122, 1.124 to provide signals with a 90° phase shift, thus also determining the direction of rotation. The signals generated by receiver lines 1.112, 1.114, 1.122, 1.124 are further processed by means of some electronic components 1.2 forming the evaluation element.

[0068] The use of the first shielding element 1.13 and the second shielding element 1.14 minimizes the negative impacts of the two detector units 1.11 and 1.12 on measurement accuracy. Specifically, it avoids unacceptable large amounts of crosstalk signals and excessive attenuation of the excitation field. Furthermore, electromagnetic interference from detector units 1.11 and 1.12 is suppressed by electronic components or external sources.

Claims

1. A scanning element (1) for use in a sensing position measuring device, the scanning element comprising electronic components (1.2) and a multilayer circuit board (1.1), wherein, The circuit board (1.1) includes A first detector unit (1.11) having a first exciter line (1.111) and a first receiver line (1.112) is disposed in the first layer (A) and the second layer (B) of the circuit board (1.1). The circuit board includes a second detector unit (1.12), which has a second actuator line (1.121) and a second receiver line (1.122). The second detector unit (1.12) is arranged in the third layer (E) and the fourth layer (F) of the circuit board (1.1). 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), wherein, The first receiver line (1.112) and the second receiver line (1.122) are arranged around an axis (R) in the circumferential direction, and The first receiver line (1.112) includes a first receiver conductor path (1.1121), and the second receiver line (1.122) includes a second receiver conductor path (1.1221), wherein the first receiver conductor path (1.1121) and the second receiver conductor path (1.1221) each have a periodic direction. The first receiver line (1.112) has a first gap (U1) along its circumferential extension, the first gap being defined by the first receiver conductor path (1.1121), and The second receiver line (1.122) has a second gap (U2) along its circumferential extension, the second gap being defined by the second receiver conductor path (1.1221), and The circuit board (1.1) has a through hole (1.15) which is arranged not only in the first gap (U1) but also in the second gap (U2).

2. The scanning element (1) according to claim 1, wherein, The via (1.15) electrically connects the first detector unit (1.11) to the third layer (E) or the fourth layer (F), or the via electrically connects the second detector unit (1.12) to the first layer (A) or the second layer (B).

3. The scanning element (1) according to claim 1 or 2, wherein, The through hole (1.15) is in electrical contact with one of the electronic components (1.2).

4. The scanning element (1) according to claim 1 or 2, wherein, The through hole (1.15) is implemented as a via.

5. The scanning element (1) according to claim 1 or 2, wherein, The first gap (U1) extends a first length L1 in the circumferential direction, and the first receiver conductor path (1.1121) has a periodic orientation with a first period length λ1, wherein: L1≥1 / 8·λ1 applies.

6. The scanning element (1) according to claim 1 or 2, wherein, The second gap (U2) extends a second length L2 in the circumferential direction, and the second receiver conductor path (1.1221) has a periodic orientation with a second periodic length λ2, wherein: L2 ≥ 1 / 8·λ2.

7. The scanning element (1) according to claim 1 or 2, wherein, The first receiver conductor path (1.1121) has a periodic orientation with a first period length, and the second receiver conductor path (1.1221) has a periodic orientation with a second period length, wherein the second period length is greater than or equal to the first period length.

8. The scanning element (1) according to claim 1 or 2, wherein, At least one of the second detector unit (1.12) and the electronic component (1.2) is arranged on the same side of the circuit board (1.1).

9. The scanning element (1) according to claim 7, wherein, The first detector unit (1.11) has a third receiver line (1.114), and the second detector unit (1.12) has a fourth receiver line (1.124).

10. The scanning element (1) according to claim 9, wherein, The third receiver line (1.114) includes a third receiver conductor path (1.1141) which has a periodic orientation, wherein the period length of the third receiver conductor path (1.1141) is less than the first period length of the first receiver conductor path (1.1121).

11. The scanning element (1) according to claim 9, wherein, The fourth receiver line (1.124) includes a fourth receiver conductor path (1.1241) which has a periodic orientation, wherein the period length of the fourth receiver conductor path (1.1241) is greater than the second period length of the second receiver conductor path (1.1221).

12. The scanning element (1) according to claim 1 or 2, wherein, The first detector unit (1.11) has a third actuator line (1.113), and the second detector unit (1.12) has a fourth actuator line (1.123).

13. The scanning element (1) according to claim 1 or 2, wherein, The first shielding layer (1.13) is arranged in the fifth layer (D), and the second shielding layer (1.14) is arranged in the sixth layer (C), and the through hole (1.15) passes through the first shielding layer (1.13) and the second shielding layer (1.14).

14. An inductive position measuring device, comprising a scanning element (1) according to any one of claims 1 to 13, a first scaling element (2), and 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 third direction (z) orthogonal to the geometric central plane.

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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