Magnetic position measuring device

Abstract

The present invention relates to a magnetic position measuring device having a magnetic scale and a sampling unit movable relative to the magnetic scale along at least one measuring direction. The magnetic scale has scale regions arranged with a uniform grating pitch P, the scale regions being provided with magnetizations oriented in opposite directions, where the grating pitch P defines the extent of the scale regions along the measuring direction. The sampling unit has at least one first detector elementary unit, which first detector elementary unit includes three strip-shaped, magnetoresistive detector elements arranged spaced apart from one another along the measuring direction, where the longitudinal directions of the detector elements are each oriented perpendicular to the measuring direction. In the first detector elementary unit, adjacent detector elements along the measuring direction have a spacing D x = P / 12.

Description

Field of the Invention

[0001] The present invention relates to a magnetic position measuring device which is suitable for measuring the positions of two objects which are arranged so as to be movable relative to one another along at least one measuring direction. Background Art

[0002] Magnetic position measuring devices generally comprise a magnetic scale (which is alternately composed of scale regions with different magnetization portions arranged at a grating pitch P) and a sampling unit (or scanning unit, i.e., Abtasteinheit) which is movable relative to the magnetic scale along at least one measuring direction. Here, the grating pitch P defines the extent of the scale region along the measuring direction. In particular, a detector assembly is provided on the side of the sampling unit, and the detector assembly has suitable magnetic field-sensitive detector elements. Here, thin layers of bar-shaped magnetoresistance, such as permalloy layers with anisotropic magnetoresistance, are considered as detector elements. This means that the resistance in the detector elements changes in the presence of an external magnetic field. The resistance change generated in the detector elements is a function of the external magnetic field here, and as the magnetic field strength increases, the characteristic curve of such detector elements undergoes distortion. The distortion of the characteristic curve then causes the output signal of the detector element to also have distortion depending on the amplitude of the scale magnetic field and has an adverse effect on the accuracy of the position measurement. This distortion is hereinafter referred to as harmonics or higher harmonics of the measuring signal fundamental frequency, which is obtained from the grating pitch P of the scale.

[0003] In order to eliminate such higher harmonics in magnetic position measuring devices, a series of solutions are known. Here, a specific geometric arrangement of the detector elements is usually provided in the detector assembly on the sampling side according to the higher harmonics to be filtered.

[0004] JP 10-185507 A proposes a specific design of a detector base unit in a detector assembly, for example, for filtering out undesired third harmonics, the detector base unit comprising three strip-shaped, magnetoresistive detector elements, which are arranged spaced apart from one another in the measuring direction; the longitudinal direction of the detector elements is oriented perpendicular to the measuring direction in each case. Adjacent detector elements have a spacing of P / 8 in the measuring direction, wherein P describes the scale length of the scale area with opposite magnetization. The central detector of the detector base unit has a greater length with a length L1 than the two outer detector elements, which each have a length L2. The length L2 of the outer detector elements is selected according to JP 10-185507 A as L2=L1 / √2 in each case. A second detector base unit of the same design is arranged spaced apart in the measuring direction, which together with the first detector base unit forms a first detector block. A first periodic incremental signal is generated here by means of the first detector block; a second periodic incremental signal is generated via the second detector block, which is phase-shifted by 90° relative to the first incremental signal. The second detector block is arranged perpendicularly to the measuring direction offset relative to the first detector block by an amount greater than the length L1 .

[0005] This filter variant is designed on the one hand only to filter out the third harmonic from the measurement signal; however, sometimes the measurement signal also contains higher harmonics which are to be eliminated.

[0006] On the other hand, the required deflection of the detector block perpendicular to the strip direction for generating the first and second incremental signals has proven to be disadvantageous. For example, if there are inhomogeneities in the material composition of the scale, the amplitude of the first incremental signal and the amplitude of the second incremental signal may differ locally, which leads to inaccurate position detection. Summary of the invention

[0007] The object of the present invention is to provide a high-precision magnetic position measuring device which allows effective filtering of a plurality of undesired harmonics from the output signal. In this case, a detector assembly which is as compact as possible should ensure a good filtering effect even when there are inhomogeneities in the sampled scale.

[0008] This object is achieved according to the invention by a magnetic position measuring device according to the invention.

[0009] Advantageous embodiments of the magnetic position measuring device according to the invention result from the measures listed in the remainder of the disclosure.

[0010] The magnetic position measuring device according to the invention comprises a magnetic scale and a sampling unit movable relative to the magnetic scale in at least one measuring direction. The magnetic scale has a scale region arranged with a uniform grating scale P, the scale region being provided with magnetizations oriented in opposite directions, wherein the grating scale P defines the extension of the scale region along the measuring direction. The sampling unit has at least one first detector elementary unit, the first detector elementary unit comprising three strip-shaped, magnetoresistive detector elements, the detector elements being arranged spaced apart from one another along the measuring direction, wherein the longitudinal directions of the detector elements are each oriented perpendicular to the measuring direction. The detector elements adjacent to one another along the measuring direction in the first detector elementary unit have a spacing D x = P / 12.

[0011] Preferably, the middle detector element has a length L along its longitudinal direction b , which is greater than the lengths L a 、L c of the two outer detector elements.

[0012] In a possible embodiment, the two outer detector elements each have a detector element length

[0013] Furthermore, it can be provided that the sampling unit has at least one first detector block, the first detector block comprising a first detector elementary unit and a second detector elementary unit, the second detector elementary unit being constructed identically to the first detector elementary unit, wherein the second detector elementary unit

[0014] - is arranged offset by a measuring direction offset V_DE x = P / 6 along the measuring direction relative to the first detector elementary unit, and - is arranged offset by a transverse offset V_DE y = L b + Δ1 perpendicular to the measuring direction relative to the first detector elementary unit, such that the first detector block has a detector block length L_DB y = 2·L b + Δ1 along the longitudinal direction of the detector elements, and wherein Δ1 = [10 μm to 100 μm] is selected.

[0015] Furthermore, it is feasible that the sampling unit also has a second detector block, which is constructed identically to the first detector block, wherein the first detector block and the second detector block together form a first detector group, and wherein the second detector block

[0016] - is offset by a measuring direction offset V_DB xis arranged at P / 22, and - is laterally offset by a lateral offset V_DB relative to the first detector block perpendicular to the measurement direction y = L_DB y is arranged at +Δ2, and wherein Δ2 is selected to be [10 μm to 100 μm].

[0017] Furthermore, the detector elements of the first detector group can be connected in series with each other, so that a periodic first sub-increment signal can be generated via the first detector group in the case of relative movement between the scale and the sampling unit.

[0018] Furthermore, it can be arranged that the sampling unit has at least three additional detector groups, and the additional detector groups are respectively constructed identically to the first detector group, wherein,

[0019] - The second detector group is arranged at a spacing G along the measurement direction x = P / 4 spaced apart from the first detector group, so that a periodic second sub-increment signal can be generated via the second detector group in the case of relative movement between the scale and the sampling unit, and the second sub-increment signal is phase-shifted by 90° relative to the first sub-increment signal, and

[0020] - The third detector group is arranged at a spacing G along the measurement direction x = P / 4 spaced apart from the second detector group, so that a periodic third sub-increment signal can be generated via the third detector group in the case of relative movement between the scale and the sampling unit, and the third sub-increment signal is phase-shifted by 90° relative to the second sub-increment signal, and

[0021] - The fourth detector group is arranged at a spacing G along the measurement direction x = P / 4 spaced apart from the third detector group, so that a periodic fourth sub-increment signal can be generated via the fourth detector group in the case of relative movement between the scale and the sampling unit, and the fourth sub-increment signal is phase-shifted by 90° relative to the third sub-increment signal.

[0022] It is feasible here that

[0023] - The first and third detector groups are connected to each other such that a periodic first increment signal can be generated from the first and third sub-increment signals, and

[0024] - The second and fourth detector groups are connected to each other such that a periodic second increment signal can be generated from the second and fourth sub-increment signals, and the second increment signal is phase-shifted by 90° relative to the first increment signal.

[0025] In an alternative embodiment, it can also be provided that the sampling unit has at least one first detector block, the first detector block including a first detector elementary cell and a second detector elementary cell, wherein the second detector elementary cell is offset relative to the first detector elementary cell by a measurement direction offset V_DE perpendicular to the measurement direction. x is arranged at P / 6, and wherein the detector element is a part of not only the first detector elementary cell but also the second detector elementary cell, so that the first detector block includes five detector elements.

[0026] It is feasible here that

[0027] - the middle detector elements of the two detector elementary cells respectively have the same length L b = L b ', and - the outermost detector elements of the two detector elementary cells respectively have the same length L a = L a ', and - the detector element that is a part of not only the first detector elementary cell but also the second detector elementary cell has a detector element length along its longitudinal direction

[0028] Preferably, here the first detector block has a detector block length L_DB y ' = 2·L b +Δ1', where Δ1' is selected to be [10 μm to 100 μm].

[0029] Furthermore, it is provided here that

[0030] - the detector element that is a part of not only the first detector elementary cell but also the second detector elementary cell is symmetrically arranged with respect to the central symmetry line of the first detector block, and

[0031] - the two other detector elements of the first detector elementary cell are arranged spaced apart on one side of the symmetry line within the range between Δ1' / 2 and L_DB y ' / 2, and

[0032] - the two other detector elements of the second detector elementary cell are arranged on the opposite side of the symmetry line within the range between Δ1' / 2 and L_DB y ' / 2.

[0033] Furthermore, the sampling unit can also have a second detector block, which is constructed identically to the first detector block, wherein the first detector block and the second detector block together form a first detector group, and wherein the second detector block

[0034] - Offset by a measurement direction offset V_DB relative to the first detector block along the measurement direction x ' = P / 22 and - offset by a lateral offset V_DB perpendicular to the measurement direction relative to the first detector block y = L_DB y ' + Δ2' and wherein Δ2' is selected to be [10 μm to 100 μm].

[0035] Advantageously, the detector elements of the detector group are connected in series with each other respectively.

[0036] Furthermore, it can be arranged that the detector elements are constructed as anisotropic magnetoresistive sensors.

[0037] In the magnetic position measuring device according to the invention, a device can be constructed based on the structure of the first detector basic unit, which also ensures filtering or suppression of multiple unwanted harmonics in the output signal, for example, simultaneous filtering of the 3rd, 5th, 7th, 9th, and 11th harmonics. This can be achieved in addition by an extremely compact spatial extension of the required structures in the detector assembly on the sampling side. Thereby, the influence of possible scale non-uniformity on the desired filtering effect can be significantly reduced.

[0038] Other details and advantages of the invention are explained by the following description of embodiments of the device according to the invention in conjunction with the drawings. Description of the Drawings

[0039] Wherein:

[0040] Figure 1 Schematic diagram showing a first embodiment of a magnetic position measuring device according to the invention suitable for detecting rotational relative movement;

[0041] Figure 2 Schematic diagram showing a second embodiment of a magnetic position measuring device according to the invention suitable for detecting linear relative movement;

[0042] Figure 3 Schematic diagram showing the structure of a detector basic unit in an embodiment of a sampling unit of a magnetic position measuring device according to the invention for illustration;

[0043] Figure 4 Schematic diagram showing the structure of a detector block in an embodiment of a sampling unit of a magnetic position measuring device according to the invention for illustration;

[0044] Figure 5 Schematic diagram showing the structure of a detector group in an embodiment of a sampling unit of a magnetic position measuring device according to the invention for illustration;

[0045] Figure 6 Schematic diagram showing the arrangement of a plurality of detector groups in an embodiment of a sampling unit with a magnetic position measuring device according to the present invention;

[0046] Figure 7 Schematic diagram showing the structure of a detector block in a further embodiment of a sampling unit of a magnetic position measuring device according to the present invention;

[0047] Figure 8 Schematic diagram showing for illustration of Figure 7 the structure of a detector group in an embodiment of. Detailed Description of the Invention

[0048] Figure 1 and 2 Diagrammatically illustrate in a highly schematic form the first and second embodiments of a magnetic position measuring device according to the present invention.

[0049] Figure 1 The variant shown in is used here to detect the relative position of two - not shown - objects, which are arranged rotatably relative to each other about a rotation axis R. Here, the first object is connected to the magnetic scale 10 of the magnetic position measuring device according to the present invention, and the second object is connected to the sampling unit 20 of the position measuring device. The scale 10 and the sampling unit 20 can move relative to each other along the measuring direction x about the rotation axis R, where the measuring direction x extends here along a circular ring about the rotation axis R.

[0050] The objects connected to the scale 10 and the sampling unit 20 can be, for example, two machine parts that are movable relative to each other about the rotation axis R, and the relative position of the machine parts can be detected by means of the magnetic position measuring device according to the present invention. For this purpose, the position measuring device generates a sampling signal that is position - dependent and in the form of a periodic incremental signal, which can be further processed by a - not shown - subsequent electronic device.

[0051] The magnetic scale 10 has scale regions 11a, 11b, which have magnetizations with opposite orientations, and the scale regions are arranged on the outer peripheral surface of a drum - shaped carrier along the measuring direction x with a uniform grating scale P. The drum - shaped carrier is rotatably arranged about the rotation axis R here. The grating scale P defines the extension of the scale regions 11a, 11b along the measuring direction x; thus, not only the scale region 11a but also the scale region 11b has the same extension along the measuring direction x. As shown by Figure 1It can be seen that the scale regions 11a, 11b are arranged such that adjacent scale regions 11a, 11b respectively have magnetized portions with opposite orientations or the same magnetic poles in the boundary region. Thus, in adjacent scale regions 11a, 11b, the magnetic north or south poles are always opposite to each other. The scale period λ in the scale 10 constructed in this way is thus obtained according to λ = 2·P.

[0052] Thereby, a periodically modulated magnetic field is generated adjacent to the scale 10 along the measurement direction x via the scale 10, and this magnetic field is sampled by the sampling unit 20. In a feasible embodiment, the grating pitch of the scale regions 11a, 11b is selected according to P = 395 μm.

[0053] On the side surface of the sampling unit 20, a detector assembly is provided, which has a plurality of magnetoresistive detector elements for generating a position-dependent sampling signal or incremental signal. The detector assembly is only schematically shown in Figure 1 and will be further explained in more detail in the course of the further description. In the present embodiment, the sampling unit 20 is fixedly arranged relative to a rotating, drum-shaped carrier with the scale 10.

[0054] In this embodiment, anisotropic magnetoresistive sensors serve as magnetoresistive detector elements in the sampling unit 20, and the anisotropic magnetoresistive sensors are also known as so-called aMR - sensors. The anisotropic magnetoresistive sensors are composed of strip-shaped thin layers made of a NiFe - alloy, such as permalloy, and the resistance of the NiFe - alloy changes in the presence of an external magnetic field. Based on the periodically modulated scale magnetic field, in the case of relative movement between the scale 10 and the sampling unit 20, a position-dependent, periodic sampling signal can thus be generated via the detector assembly of the sampling unit 20, which has a signal period SP = P.

[0055] The sampling signal generated by means of the magnetic position measuring device according to the invention is transmitted to a subsequent electronic device, which is also not shown in the drawings, and this subsequent electronic device further processes the sampling signal depending on the application. For example, the subsequent electronic device can be a superior machine control device that controls the relative movement of two machine parts that are movable relative to each other.

[0056] A second variant of the magnetic position measuring device according to the invention is shown in Figure 2 for detecting the relative position of two - also not shown - objects that are arranged movably relative to each other along a linear measurement direction x. The first object is again connected to the magnetic scale 110 of the magnetic position measuring device according to the invention, and the second object is connected to the sampling unit 120 of the position measuring device.

[0057] The scale 110 extends here along the linear measuring direction x and also has scale regions 111a, 111b with magnetized portions of opposite orientation. The scale regions 111a, 111b are arranged on a suitable carrier along the measuring direction x with a uniform grating pitch P as in the rotational variant.

[0058] In this example, the specific construction of the sampling unit 120 and in particular of the detector assembly with magnetoresistive detector elements cannot be seen from the figure. Subsequently, with the aid of Figures 3 to 6 a feasible variant of the sampling unit 120 of the magnetic position measuring device according to the invention will be explained in detail; it can be used not only in the rotational embodiment of the device according to the invention but also in the linear embodiment of the device according to the invention.

[0059] Figure 3 A top view of a first detector elementary unit 21.1 in the detector assembly of the sampling unit is shown in a schematic form, which sampling unit is shown adjacent to a section of the magnetic scale 10 sampled above this sampling unit. According to this embodiment, the detector elementary unit 21.1 comprises three bar-shaped, magnetoresistive detector elements 21.1a, 21.1b, 21.1c, which are arranged spaced apart from one another in the measuring direction x. The detector elements 21.1a to 21.1c are rectangularly shaped, wherein the longitudinally extending directions y of the detector elements, which are parallel to one another, each extend perpendicular to the measuring direction x.

[0060] The spacing D provided along the measuring direction x between adjacent detector elements 21.1a - 21.1c x is selected in the magnetic position measuring device according to the invention according to the grating pitch P of the scale regions 11a, 11b on the scale 10 and is x = P / 12.

[0061] As can be seen from Figure 3 the middle detector element 21.1b has a length L along its longitudinal direction y b , which length is selected to be greater than the lengths L a , L c of the two outer detector elements 21.1a, 21.1c. a The lengths L c of these two outer detector elements 21.1a, 21.1c are

[0062] selected to be the same and each have a length b In a feasible embodiment, in the case of a grating pitch P = 395 μm, the length L bSelection is made for = 80 μm, whereby for the lengths L of these two outer detector elements 21.1a, 21.1c a 、L c According to the relationship L mentioned above a = L c = 46.19 μm is obtained.

[0063] This configuration of the first detector basic unit 21.1 produces a defined filtering effect on the harmonics contained in the periodic sampling signal. Thus, with the detector basic unit 21.1 configured in this way, the fifth and seventh harmonics can be filtered out from the following sampling signal, which is generated when sampling the magnetic scale 10 during the relative movement between the scale 10 and the sampling unit.

[0064] In principle, in this example of the first detector basic unit 21.1, it is not necessarily required that the two outer detector elements 21.1a, 21.1c be arranged centered about the symmetry line S of the middle detector element 21.1b as set in the example of Figure 3 . Alternatively, it is also feasible that the detector elements 21.1a, 21.1c are arranged movably in the following region along their longitudinal direction y, and this region is preset by the length L of the middle detector element 21.1b b .

[0065] In order to remove other harmonics from the sampling signal in addition to the fifth and seventh harmonics, the detector assembly composed of the first detector basic unit 21.1 in the sampling unit can be appropriately modified or extended. A feasible solution for additional filtering of the third and ninth harmonics is illustrated below with the schematic diagram in Figure 4 .

[0066] In this embodiment, it is set that the detector assembly in the sampling unit has, in addition to the first detector basic unit 21.1, a second detector basic unit 21.2. The second detector basic unit 21.2 is in principle constructed in the same way as the first detector basic unit 21.1, that is, similar to the first detector basic unit 21.1, it also includes three detector elements 21.2a - 21.2c, and the lengths of the three detector elements along the direction y and their relative arrangements to each other along the measurement direction are selected similar to those of the first detector basic unit 21.1.

[0067] The second detector basic unit 21.2 is arranged in the detector assembly at a specific relative position with respect to the first detector basic unit 21.1. Thus, the second detector basic unit 21.2 is offset by a measurement direction offset V_DE along the measurement direction x with respect to the first detector basic unit 21.1 xArranged at P / 6. Additionally, it is arranged such that the second detector elementary unit 21.2 is offset by a lateral offset V_DE relative to the first detector elementary unit 21.1 perpendicular to the measurement direction x (i.e., along the y direction). y = L b Arranged at +Δ1. Here, the parameter Δ1 is preferably selected within the range of Δ1 = [10 μm to 100 μm].

[0068] Thereby, a first detector block 22.1 is constructed via these two detector elementary units 21.1, 21.2. The first detector block 22.1 has a detector block length L_DB along the longitudinal direction y of the detector elements 21.1a - 21.1c, 21.2a - 21.2c y = 2·L b +Δ1.

[0069] If in one embodiment the parameter Δ1 is selected, for example, Δ1 = 80 μm, then in the case of L b = 80 μm, a detector block length L_DB along the y direction is produced y = 240 μm. Thereby, by means of the detector assembly, it is thus possible to filter out undesired harmonics from the generated sampling signal, and the detector assembly is constructed very compactly along the y direction. If the typical extension of possible scale inhomogeneities is present on the order of about 300 μm, then the influence of possible scale inhomogeneities on the desired filtering effect can be significantly reduced by means of such a constructed detector assembly.

[0070] If in addition to filtering the 3rd, 5th, 7th, and 9th harmonics, the 11th harmonic is also to be filtered out from the sampling signal, then the detector assembly formed by the first detector block 22.1 can be Figure 4 extended again in the sampling unit. The following illustrates a feasible solution for the additional filtering of the 11th harmonic with the aid of the Figure 5 schematic diagram in.

[0071] In this embodiment, it is arranged such that the detector assembly in the sampling unit, in addition to the first detector block 22.1, also has a second detector block 22.2. The second detector block 22.2 is constructed in principle in the same way as the first detector block 22.1 and is also composed of two detector elementary units, which have a specific relative arrangement relative to each other.

[0072] The second detector block 22.2 is placed in the detector assembly with a specific relative arrangement relative to the first detector block 22.1. Thereby, on the one hand, it is arranged such that the second detector block is offset by a measurement direction offset V_DB relative to the first detector block 22.1 along the measurement direction x x= P / 22 is arranged. On the other hand, the second detector block 22.2 is offset by a lateral offset V_DB perpendicular to the measurement direction x with respect to the first detector block 22.1 y = L_DB y +Δ2 is arranged. The parameter Δ2 is preferably selected in the range of Δ2 = [10 μm to 100 μm] here.

[0073] In this embodiment, a first detector group 23.1 is constructed via two detector blocks 22.1, 22.2. The first detector group is suitable for filtering out the 3rd, 5th, 7th, 9th, and 11th harmonics from the sampling signal.

[0074] All detector elements of the first detector group 23.1 are connected in series with each other in the sampling unit. Thus, a periodic first sub-increment signal can be generated when the scale 10 and the sampling unit move relative to each other. This first sub-increment signal is denoted by S_0 below.

[0075] In order to be able to provide an increment signal with a phase shift of 90° to a subsequent electronic device downstream of the magnetic position measuring device according to the invention, Figure 5 the detector assembly in can be expanded again. The corresponding variants of such a detector assembly are shown schematically in Figure 6 In addition, connection lines are shown in this figure. The connection lines connect the detector elements in series with each other within the detector group 10; the connection lines can be constructed, for example, as copper lines between the permalloy strip layers of the detector elements.

[0076] Figure 6 The detector assembly shown in in addition to the first detector group 23.1 according to the example in Figure 5 also includes three additional detector groups 23.2 - 23.4. The additional detector groups are each constructed in principle in the same way as the first detector group 23.1.

[0077] Here, the second detector group 23.2 is arranged at a spacing G x = P / 4 spaced apart from the first detector group 23.1 along the measurement direction x. Thus, when the scale 10 and the sampling unit move relative to each other, a periodic second sub-increment signal S_90 can be generated via the second detector group 23.2. This second sub-increment signal is phase-shifted by 90° with respect to the first sub-increment signal S_0.

[0078] The third detector group 23.3 is furthermore arranged at a spacing G along the measurement direction x xis arranged spaced apart from the second detector group 23.2 by =P / 4, and in this case, when the scale 10 and the sampling unit move relative to each other, a periodic third sub-increment signal S_180 can be generated, and this third sub-increment signal is phase-shifted by 90° relative to the second sub-increment signal S_90.

[0079] Finally, the fourth detector group 23.4 is arranged along the measurement direction x at a pitch G x =P / 4 spaced apart from the third detector group 23.3, so that in this case, when the scale 10 and the sampling unit move relative to each other, a periodic fourth sub-increment signal S_270 can be generated via the fourth detector group 23.4, and this fourth sub-increment signal is phase-shifted by 90° relative to the third sub-increment signal S_180.

[0080] In order to generate two periodic increment signals with a 90° phase shift required for subsequent electronic devices from the four sub-increment signals S_0, S_90, S_180, S_270 generated in this way, it can also be arranged that, on the one hand, the first and third detector groups 23.1, 23.3 are interconnected via a half-bridge such that a periodic first increment signal SIN can be generated from the first and third sub-increment signals S_0, S_180. On the other hand, in this case, the second and fourth detector groups 23.2, 23.4 are interconnected via another half-bridge such that a periodic second increment signal COS can be generated from the second and fourth sub-increment signals S_90, S_270), and this second increment signal is phase-shifted by 90° relative to the first increment signal SIN. The corresponding interconnection of the detector elements is Figure 6 not shown in detail here, but only schematically.

[0081] Alternatively, the generation of the increment signals SIN, COS can also be achieved by a full bridge, which is respectively composed of two half-bridges connected in parallel with each other. Four additional detector groups (23.1', 23.2', 23.3' and 23.4') are provided to form the full bridge, and these four additional detector groups are constructed in the same way as the first to fourth detector groups according to the illustrated example and are arranged along the measurement direction x offset by the grating scale P relative to the first four detector groups. The first increment signal SIN is then generated by the full-bridge connection of the groups 23.1, 23.3, 23.1' and 23.3'. The second increment signal COS with a 90° phase shift is generated by the full-bridge connection of the groups 23.2, 23.4, 23.2' and 23.4'.

[0082] In addition, such a detector assembly can be extended into a matrix composed of multiple detector groups, which matrix is composed of rows of multiple detector groups arranged along the measurement direction x and columns with multiple detector groups arranged along the y direction. For example, for this purpose, a matrix composed of, for example, eight rows and four columns of detector groups can be constructed. Through such a detector assembly, a further improved averaging of the generated sampling signals can be achieved. In addition, the errors caused by the imperfect attachment of the position measuring device according to the invention can be minimized in corresponding applications.

[0083] A further embodiment of a suitable detector block or detector group in the detector assembly for alternatively constructing the sampling unit of the position measuring device according to the invention is explained below with the aid of Figure 7 and 8 illustrated; here, the decisive differences from the variants explained until now are discussed in writing.

[0084] In Figure 7 a possible embodiment for constructing a first detector block 222.1 including two detector basic monomers 221.1, 221.2 is shown, wherein the second detector basic monomer 221.2 is offset by a measurement direction offset V_DE x = P / 6 along the measurement direction x relative to the first detector basic monomer 221.1. In addition, it is arranged here that the detector element 221.3 is not only a part of the first detector basic monomer 221.1 but also a part of the second detector basic monomer 221.2. As can be seen from the drawings, the detector element is the third detector element from the left in the first detector basic monomer 222.1 or the first detector element from the left in the second detector basic monomer. In addition, the first and second detector basic monomers 221.1, 221.2 each further include two other detector elements 221.1a, 221.1b or 221.2a, 221.2b. Thus, Figure 7 the first detector block 222.1 shown in

[0085] has a total of five detector elements 221.1a, 221.1b, 221.3, 221.2a, 221.2b. x = P / 12.

[0086] In these two detector basic monomers 221.1, 221.2, the middle detector elements 221.1b, 221.2b each have the same length L b = L b'; Similarly, the outermost detector elements 221.1a and 221.2a of these two detector basic units 221.1 and 221.2 respectively have the same length L a = L a '.

[0087] This detector element 221.3, which is not only a component of the first detector basic unit 221.1 but also a component of the second detector basic unit 221.2, has a length in the illustrated embodiment For Figure 7 the first detector block 221.1 shown in, thus obtaining the detector block length L_DB along the longitudinal direction y of the detector elements 221.1a, 221.1b, 221.3, 221.2a, 221.2b y ' = 2·L b + Δ1'; Here, Δ1' = [10 μm to 100 μm] is selected.

[0088] So also from Figure 7 it can be seen that the detector element 221.3, which is not only a component of the first detector basic unit 221.1 but also a component of the second detector basic unit 221.2, is symmetrically arranged with respect to the central symmetry line S of the first detector block 221.1. The two other detector elements 221.1a and 221.1b of the first detector basic unit 221.1 are additionally spaced apart within the range between Δ1' / 2 and L_DB y ' / 2 on one side of the symmetry line S. The two other detector elements 221.2a and 221.2b of the second detector basic unit 221.2 are arranged on the opposite side of the symmetry line S within the range between Δ1' / 2 and L_DB y ' / 2.

[0089] With the first detector block 221.1 constructed in this way, the 3rd, 5th, 7th, and 9th harmonics can be filtered out from the periodic sampling signal. If in addition the 11th harmonic is also to be filtered out, the detector assembly can be supplemented with another, second detector block 222.2 similar to the above example, as is schematically shown in Figure 8 The second detector block 222.2 is constructed in principle the same as the first detector block 222.1; this second detector block together with the first detector block 222.1 in turn forms a first detector group 223.1, which is suitable for generating a first sub-increment signal.

[0090] The second detector block 222.2 is offset along the measurement direction x with respect to the first detector block 222.1 by the measurement direction offset V_DB x' = P / 22 is arranged. Perpendicular to the measurement direction x, the second detector block 222.2 is offset by a lateral offset V_DB with respect to the first detector block 22.1 y = L_DB y '+ Δ2' is arranged; here, Δ2' = [10 μm to 100 μm] is selected.

[0091] As in the above example, Figure 8 the detector assembly can of course also be supplemented by three additional detector groups, via which three additional sub-increment signals can be generated. A suitable connection of a total of four detector groups can then in turn form two increment signals SIN, COS with a phase offset of 90°.

[0092] In addition to the specifically described embodiments, there are of course also other design possibilities for the magnetic position measuring device according to the invention within the scope of the invention.

Claims

1. A magnetic position measuring device, the magnetic position measuring device having a magnetic scale (10; 110) and a sampling unit (20; 120) movable relative to the magnetic scale in at least one measuring direction (x), wherein, - the magnetic scale (10; 110) has scale regions (11a, 11b; 111a, 111b) arranged with a uniform grating pitch P, the scale regions having magnetizations with opposite orientations, wherein the grating pitch P defines the extent of the scale regions (11a, 11b; 111a, 111b) along the measuring direction (x), and - the sampling unit (20; 120) has at least one first detector elementary unit (21.1), the first detector elementary unit including three strip-shaped, magnetoresistive detector elements (21.1a - 21.1c), the detector elements being arranged spaced apart from one another in the measuring direction (x), wherein the longitudinal direction (y) of the detector elements (21.1a - 21.1c) is respectively oriented perpendicular to the measuring direction (x), characterized in that The detector elements (21.1a, 21.1c) adjacent to each other along the measurement direction (x) in the first detector basic unit (21.1) have a spacing D relative to each other x = P / 12, and the middle detector element (21.1b) has a length L along its longitudinal direction (y) b , and the length is greater than the lengths L a , L c of the two outer detector elements (21.1a, 21.1c), and the two outer detector elements (21.1a, 21.1c) each have a detector element length The sampling unit (20; 120) has at least one first detector block (22.1), the first detector block includes the first detector basic unit (21.1) and a second detector basic unit (21.2), the second detector basic unit is constructed identically to the first detector basic unit (21.1), wherein the second detector basic unit (21.2) - offset by a measurement direction offset V_DE relative to the first detector basic unit (21.1) along the measurement direction (x) x is arranged at P / 6, and - offset transversely by a transverse offset V_DE relative to the first detector basic unit (21.1) perpendicular to the measurement direction (x) y = L b + Δ1 arranged such that the first detector block (22.1) has a detector block length L_DB along the longitudinal direction (y) of the detector elements (21.1a - 21.1c; 21.2a - 21.2c) y = 2·L b + Δ1, and wherein Δ1 = [10 μm to 100 μm] is selected.

2. The magnetic position measuring device according to claim 1, characterized in that the sampling unit (20; 120) further has a second detector block (22.2), the second detector block being constructed identically to the first detector block (22.1), wherein the first detector block and the second detector block (22.1, 22.2) together form a first detector group (23.1), and wherein the second detector block (22.2) - Offset the measurement direction by a measurement direction offset V_DB relative to the first detector block (22.1) along the measurement direction (x) x is arranged at P / 22, and - offset transversely by a transverse offset V_DB relative to the first detector block (22.1) perpendicular to the measurement direction y = L_DB y + Δ2 is arranged, and wherein Δ2 is selected to be in the range of [10 μm to 100 μm].

3. The magnetic position measuring device according to claim 2, characterized in that, the detector elements of the first detector group (23.1) are connected in series with one another, such that in the case of relative movement of the scale (10; 110) and the sampling unit (20; 120), a periodic first sub-increment signal (S_0) can be generated via the first detector group (23.1).

4. The magnetic position measuring device according to claim 3, characterized in that, the sampling unit (20; 120) has at least three further detector groups (23.2, 23.3, 23.4), the further detector groups each being constructed identically to the first detector group (23.1), wherein, - The second detector group (23.2) is arranged at a spacing G along the measurement direction (x) x = P / 4 spaced apart from the first detector group (23.1), so that a periodic second sub-increment signal (S_90) can be generated via the second detector group (23.2) when the scale (10; 110) and the sampling unit (20; 120) move relative to each other, and the second sub-increment signal is phase-shifted by 90° relative to the first sub-increment signal (S_0), and - The third detector group (23.3) is arranged at a spacing G along the measurement direction (x) x = P / 4 spaced apart from the second detector group (23.2) such that a periodic third sub-increment signal (S_180) can be generated via the third detector group (23.3) when the scale (10; 110) and the sampling unit (20; 120) move relative to each other, the third sub-increment signal being phase-shifted by 90° relative to the second sub-increment signal (S_90), and - The fourth detector group (23.4) is arranged at a spacing G along the measurement direction (x) x = P / 4 and spaced apart from the third detector group (23.3), so that a periodic fourth sub-increment signal (S_270) can be generated via the fourth detector group (23.4) when the scale (10; 110) and the sampling unit (20; 120) move relative to each other. The fourth sub-increment signal is phase-shifted by 90° relative to the third sub-increment signal (S_180).

5. The magnetic position measuring device according to claim 4, characterized in that - the first detector group (23.1) and the third detector group (23.3) are interconnected such that a periodic first increment signal (SIN) can be generated from the first sub-increment signal (S_0) and the third sub-increment signal (S_180), and - the second detector group (23.2) and the fourth detector group (23.4) are interconnected such that a periodic second increment signal (COS) can be generated from the second sub-increment signal (S_90) and the fourth sub-increment signal (S_270), the second increment signal being phase-shifted by 90° relative to the first increment signal (SIN).

6. A magnetic position measuring device, the magnetic position measuring device having a magnetic scale (10; 110) and a sampling unit (20; 120) movable relative to the magnetic scale in at least one measuring direction (x), wherein, - The magnetic scale (10; 110) has scale regions (11a, 11b; 111a, 111b) arranged with a uniform grating pitch P, the scale regions being provided with magnetizations in opposite orientations, where the grating pitch P defines the extent of the scale regions (11a, 11b; 111a, 111b) along the measuring direction (x), and - The sampling unit (20; 120) has at least one first detector elementary unit (21.1), the first detector elementary unit comprising three strip-shaped, magnetoresistive detector elements (21.1a - 21.1c), the detector elements being arranged spaced apart from one another along the measuring direction (x), where the longitudinal direction (y) of the detector elements (21.1a - 21.1c) is respectively oriented perpendicular to the measuring direction (x), characterized in that - The sampling unit (20; 120) has at least one first detector block (222.1), the first detector block including the first detector elementary monomer (221.1) and the second detector elementary monomer (221.2), wherein the second detector elementary monomer (221.2) is offset by a measurement direction offset V_DE with respect to the first detector elementary monomer (222.1) perpendicular to the measurement direction (x). x is arranged at P / 6, and wherein the detector element (221.3) is a part of not only the first detector elementary monomer (221.1) but also the second detector elementary monomer (221.2), such that the first detector block (221) includes five detector elements (221.1a, 221.1b, 221.3, 221.2a, 221.2b). - The detector elements (221.1b, 221.2b) in the middle of these two basic detector monomers (221.1, 221.2) respectively have the same length L b = L b ', and - The outermost detector elements (221.1a, 221.2a) of the two detector basic monomers (221.1, 221.2) respectively have the same length L a = L a ', and - The detector element (221.3), which is a component not only of the first detector basic unit (221.1) but also of the second detector basic unit (221.2), has a length along its longitudinal direction (y).

7. The magnetic position measuring device according to claim 6, characterized in that, The first detector block (222.1) has a detector block length L_DB along the longitudinal direction (y) of the detector elements (221.1a, 221.1b, 221.3, 221.2a, 221.2b). y ' = 2·L b + Δ1', and where Δ1' is selected to be [10 μm to 100 μm].

8. The magnetic position measuring device according to claim 7, characterized in that - The detector element (221.3), which is a part not only of the first detector elementary unit (221.1) but also of the second detector elementary unit (221.2), is arranged symmetrically with respect to the central symmetry line (S) of the first detector block (221.1), and - The two further detector elements (221.1a, 221.1b) of the first detector basic unit (221.1) are arranged spaced apart on one side of the symmetry line (S) in the range between Δ1' / 2 and L_DB y ' / 2, and - Two further detector elements (221.2a, 221.2b) of the second detector elementary unit (221.2) are arranged on opposite sides of the symmetry line (S) in the range between Δ1' / 2 and L_DB y ' / 2.

9. The magnetic position measuring device according to claim 8, characterized in that, The sampling unit further has a second detector block (222.2), which is constructed identically to the first detector block (222.1), where the first detector block (222.1) and the second detector block (222.2) together form a first detector group (223.1), and where the second detector block (222.2) - Offset the measurement direction by a measurement direction offset V_DB relative to the first detector block (222.1) along the measurement direction (x). x is arranged at '= P / 22, and - offset transversely by a transverse offset V_DB perpendicular to the measurement direction (x) relative to the first detector block (222.1) y = L_DB y arranged '+Δ2', and wherein Δ2' = [10 μm to 100 μm] is selected.

10. The magnetic position measuring device according to claim 9, characterized in that, The detector elements of the detector group are connected in series with one another.

11. The magnetic position measuring device according to any one of claims 1 to 10, characterized in that, The detector elements are configured as anisotropic magnetoresistive sensors.

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