JP2022106663A - Sensing winding configuration for electromagnetic induction encoder - Google Patents

Abstract

To provide an electromagnetic induction encoder usable for measuring the relative position between two elements along a measurement axis direction.SOLUTION: An electromagnetic induction encoder includes a scale, a detection unit, and a signal processing unit. The scale includes a periodic pattern of signal modulating elements (SMEs) arranged along a measuring axis (MA) with a spatial wavelength W1. The detection unit comprises sensing elements and a field generating coil that generates a change in magnetic flux. The sensing elements comprise conductive loops and outputs detection signals in response to a local influence on the change in magnetic flux provided by adjacent SMEs. Part or all of the conductive loops are configured in accordance with an inter-loop shift relationship in which the equal "shift ratios" of the loops are shifted in opposite directions by W1/4K. K is an odd integer. The inter-loop shift relationship can be used for preventing the K-th spatial harmonic components of the detection signals, and can solve a long-time, harmful layout problem.SELECTED DRAWING: Figure 14

Description

The present disclosure relates to measuring instruments, and more particularly to electromagnetic induction encoders that can be used in precision measuring instruments.

Different encoder configurations can include different types of optical, capacitive, magnetic, electromagnetic induction, moving and / or position transducers. These transducers use various geometric configurations of transmitters and receivers within the read head to measure movement between the read head and the scale.

US Pat. No. 6,011,389 ('389), US Pat. No. 7,239,130 ('130), and US Pat. No. 6,124,708 ('708). ) Describes an electromagnetic induction transducer that can be used in high precision applications. US Pat. No. 5,973,494 (Patent No. '494) and US Pat. No. 6,002,250 (Patent No. '250) are electromagnetic induction incremental calipers and linears that include signal generation and processing circuits. Explains the scale. US Pat. No. 5,886,519 (Patent No. 519), US Pat. No. 5,841,274 (Patent No. '274), and US Pat. No. 5,894,678 (Patent No. '678). ) Describes an electromagnetic induction type absolute caliper and an electronic winding scale using an electromagnetic induction type transducer. US Pat. Nos. 10,520,335 ('335 patent), US Pat. No. 10,612,943 ('943 patent), and US Pat. No. 10,775,199 ('199 patent). ) Discloses winding configuration improvements that are useful for increasing the accuracy, robustness and ease of alignment of electromagnetic induction encoders. All of the above are incorporated herein by reference in their entirety. As described in these patents and applications, electromagnetic induction transducers can be manufactured using printed circuit board technology and are largely immune to fouling.

However, these systems are limited in their ability to provide a particular combination of features that the user desires, such as small size, high resolution, accuracy, low cost, robustness against dirt, robustness against misalignment, etc. There is. An encoder configuration that provides an improved combination of such characteristics is desired.

This overview is provided to provide a simplified selection of concepts that will be further explained in the detailed description below. This summary is not intended to identify important features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

An electromagnetic induction encoder that can be used to measure the relative position between two elements along the measurement axis direction is provided. In various embodiments, the electromagnetic induction encoder includes a scale, a detector, and a signal processor.

The scale extends along the measurement axis direction and includes a periodic scale pattern that includes at least a first type of signal modulation element. The periodic scale pattern has a spatial wavelength W1. The first type of signal modulation element includes a plurality of conductive plates or a plurality of conductive loops arranged along the measurement axis direction corresponding to the spatial wavelength W1. The detection unit is mounted close to the periodic scale pattern and is configured to move along the measurement axis direction with respect to the periodic scale pattern. In various embodiments, the detector provides a magnetic field generation coil and at least one respective set of sensing elements corresponding to their respective nominal spatial phases (eg, two sets of spatial phases that differ by 90 degrees, each providing an orthogonal signal. Or one in which each of the three sets of spatial phases differing 120 degrees provides a three-phase signal). The magnetic field generation coil is fixed to the substrate and surrounds an internal region that is aligned with the effective region of the periodic scale pattern of the signal modulation element during operation. As used herein, the term "surrounding" can mean, in various embodiments, fully or partially encircling. The only constraint is that the magnetic field generating coil is configured to generate a flux change in the internal region in response to a coil drive signal to support operation according to the principles disclosed and claimed herein. Is Rukoto. Each detection element set is arranged along the measurement axis direction and fixed to the substrate. Members of the sensing element set are conductive loops or conductive loops that define the sensing element effective region EffASEN corresponding to the portion of the sensing element that is aligned with or overlaps the internal region surrounded by the magnetic field generation coil. It consists of parts.

Each detection element set is configured to provide a detection signal according to the local effect on the magnetic flux change provided by the adjacent signal modulation elements of the scale pattern and corresponds to their respective nominal spatial phases. .. The signal processing unit may be operably connected to the detection unit to provide a coil drive signal and determines the relative position of the detection unit and the scale pattern based on the detection signal input from the detection unit.

In various embodiments of the first type according to the principles disclosed herein (eg, shown in FIGS. 9-13), at least one respective set of sensing elements corresponding to their respective nominal spatial phases is combined. It comprises the features A1, B1 and C1 described above, and is further combined with at least one of the features D1 or E1 defined as follows.

A1) A plurality of positive loops corresponding to the first winding direction or polarity and the same number of negative loops corresponding to the second winding direction or polarity opposite to the first winding are provided.

B1) Each of the positive loop and the negative loop has all detection element effective regions EffASEN that are aligned with the internal region or overlap with one or more internal regions, and one or more perpendicular to the measurement axis direction. Defined to have an effective y-axis dimension EffYSEN along the y-axis direction, which is the sum of the dimensions of the internal regions of the DSENavg = (EffASEN / EffYSEN) is configured to be within the range of 0.33 * W1 ± 15%.

C1) The positive electrode loop is configured such that the effective region of the detection element is arranged in a positive loop regulation relationship (abbreviated as a positive loop regulation relationship) with respect to each nominal spatial phase of each detection element set, and is a negative electrode. The sex loop is configured such that the detection element effective region is arranged in a negative loop regulation relationship (abbreviated as a negative loop regulation relationship) with respect to each nominal spatial phase of each detection element set. In the positive loop regulation relationship, the shift ratio up to half of the effective region of all detection elements in a plurality of positive electrode loops is (W1) / 4K in relation to each nominal spatial phase along the measurement axis direction in the first direction. Shifted, the nominally same shift ratio of all detection element effective regions of multiple positive loops is along the measurement axis direction in the direction opposite to the first direction by (W1) / 4K in relation to each nominal spatial phase. The two shift ratios of the effective regions of all the detection elements in the positive loop region are shifted relative to each other by (W1) / 2K, and K is among 3, 5, 7, and 9. It is characterized by being one of. In the negative loop regulation relationship, the shift ratio up to half of the effective region of all the detection elements of the plurality of negative electrode loops is (W1) / 4K in relation to the respective nominal spatial phases along the measurement axis direction in the first direction. Shifted, the nominally same shift ratio of all detection element effective regions of multiple negative electrode loops is along the measurement axis direction in the direction opposite to the first direction by (W1) / 4K in relation to each nominal spatial phase. The two shift ratios of the effective regions of all the detection elements in the negative electrode loop region are shifted relative to each other by (W1) / 2K.

D1) Each of the positive and negative loops is composed of a detection element effective region EffASEN in which the maximum dimension DSENmax in the measurement axis direction is 0.45 * W1 at the maximum.

E1) Each detection element set corresponding to each nominal spatial phase (SETSENPh0) has a first separation portion composed of the same number of positive electrode loops and negative electrode loops, and the first separation portion and the measurement axis direction. It is composed of two parts, a second separation part that is nominally aligned along the line and has the same number of positive and negative loops as the first separation part, and is composed of a first separation part and a second separation part. The separation part is separated by a gap located along the measurement axis direction between the first separation part and the second separation part, and the gap is a positive loop or a negative electrode along the measurement axis direction. It has at least the same width as one of the loops, and the effective region of the positive loop or the effective region of the negative loop of each detection element set is not located in the gap.

As a result, each detection element set corresponding to each nominal spatial phase (SETSENPh0) has a practical configuration for providing a spatially filtered detection signal or a plurality of detection signals, and has a detection unit and a scale. Potentially unwanted third-order spatial harmonic detection signal components and potentially unwanted third-order spatial harmonics that can cause a determined relative position error with the pattern. It can be used to reduce or suppress both wave detection signal components.

As a result of implementing features A1, B1, and C1 together with at least one of features D1 and / or E1 as described above, each detection element set corresponding to each nominal spatial phase thereby has a detector and a scale pattern. Both potentially unwanted third-order spatial harmonic signal components and potentially unwanted K-th-order spatial harmonic signal components that can contribute to the determined relative position error between It is configured to provide a spatially filtered detection signal or multiple detection signals that can be used to reduce or suppress. In addition, this configuration provides the spatial filtering described above, while at the same time providing a novel "layout-friendly" loop arrangement to solve long-standing harmful layout problems, as detailed below. In some embodiments of the first type, it may be particularly advantageous when K = 5. In a particular embodiment of the first type, at least half or more of the positive and negative loops are at least 0.29 * W1 and up to 0, as described in more detail below with reference to various figures. It is advantageous if it is configured to provide a detection element average dimension DSENavg of .31 * W1.

In various embodiments of the first type, the respective positive or negative properties included in each detection element set comprising features A1, B1, C1 and at least one of features D1 and / or E1. The loop may be configured to provide each detection element effective region EffASEN that does not overlap the detection element effective region EffASEN of each of the other positive or negative loops included in the respective detection element set. This allows for low manufacturing cost layouts and also eliminates harmful loop shape irregularities resulting from layout problems that occur with traditional methods of providing spatial filtering and misalignment error reduction. Can be eliminated. With conventional techniques, there has been no configuration that can realize spatial filtering performance, robustness against misalignment, and a relatively ideal loop shape of the entire detection element with an economical manufacturing layout.

In some embodiments of the first type, at least each of the first set of sensing elements corresponding to each nominal spatial phase comprises features A1, B1, C1, and D1 and does not include feature E1. In some such embodiments, each first set of sensing elements has a first adjacent portion composed of the same number of positive and negative loops, and a first adjacent portion in the measurement axial direction. It is nominally aligned along the line and may include a second adjacent portion composed of the same number of positive and negative loops as the first adjacent portion. The first and second flanking sections may be located closer to each other along the measurement axis direction than the width of one of the positive or negative loops (hence the "adjacent" section herein. The loops of the first and second adjacent parts closest to each other may have opposite loop polarities. In some such embodiments, the electromagnetic induction encoder has at least a second set of sensing elements corresponding to each nominal spatial phase that is 90 degrees different from the nominal spatial phase of each set of first sensing elements. It may be included. Each of the second detection element sets comprises features A1, B1, C1, D1, and E1. Each of the second sets of sensing elements has the same loop polarity in the respective loops of its first and second separators that are closest to each other. Each first set of sensing elements has a first region centroid of its entire effective region of sensing elements located along the measurement axis between its first and second adjacent portions. Each of the second sets of detection elements has a second region center of gravity of its entire detection element effective region located along the measurement axis between its first and second separations. In each of the first and second detection element sets, the centers of gravity of the first and second regions are arranged at the same position along the measurement axis direction. Such center-of-gravity embodiments offer some advantage in eliminating certain errors due to "pitch" shifts between the detector and the scale pattern, while at the same time economical layout and manufacturing. Can be facilitated. In some such embodiments, the respective positive or negative loops contained in one of the first or second respective detection element sets are the same in the first or second detection element set. It is configured to provide each detection element effective region EffASEN that does not overlap with the detection element effective region EffASEN of each of the other positive or negative loops contained in one.

As outlined above, in various embodiments that include two adjacent portions, or two separate portions, the electromagnetic induction encoder may be configured according to either M1 or M2. M1) The first adjacent (or separated) unit is configured to output the first detection signal, the second adjacent (or separated) unit is configured to output the second detection signal, and signal processing. The unit is configured to determine the relative position between the detector and the scale pattern, at least partially based on the combination of the first and second signals. Alternatively, M2) the first adjacent (or separated) part is connected in series with the second adjacent (or separated) part to form a composite signal, and the series connection is the first and second parts of the composite signal. Each signal contribution is configured to be added, and the signal processor is configured to determine the relative position between the detector and the scale pattern, at least partially based on the composite signal. When the adjacencies are connected in series, the first and second adjacencies can, in some embodiments, be interpreted as part of a continuous, uninterrupted set of sensing elements.

In some embodiments of the first type, at least each first set of sensing elements corresponding to each nominal spatial phase comprises features A1, B1, C1, and E1. In some such embodiments, the first respective set of sensing elements may be configured such that the respective loops of its first and second separators closest to each other have the same loop polarity. Some such embodiments may include at least each second set of sensing elements corresponding to each nominal spatial phase 90 degrees different from the nominal spatial phase of each first set of sensing elements. Each of the second detection element sets comprises features A1, B1, C1, and E1. Each of the second sets of sensing elements has opposite loop polarities in the respective loops of its first and second separators closest to each other. Each first set of detection elements has a first region center of gravity of its entire detection element effective region located along the measurement axis between its first and second separations. Each of the second sets of detection elements has a second region center of gravity of its entire detection element effective region located along the measurement axis between its first and second separations. In each of the first and second detection element sets, the centers of gravity of the first and second regions are arranged at the same position along the measurement axis direction. In some such embodiments, the respective positive or negative loops contained in one of the first or second respective detection element sets are the same in the first or second detection element set. It is configured to provide each detection element effective region EffASEN that does not overlap with the detection element effective region EffASEN of each of the other positive or negative loops contained in one. In some such embodiments, both the first and second sets of sensing elements include both features D1 and E1.

In some embodiments of the first type, at least each set of sensing elements corresponding to each nominal spatial phase comprises features A1, B1, C1, and at least feature D1, according to feature C1. Multiple pairs of detection element effective regions of adjacent positive and negative loops are shifted in the first direction along the measurement axis by (W1) / 4K, and the same number of adjacent positive and negative loops are used. The pair of effective regions of the detection element is shifted by (W1) / 4K in the direction opposite to the first direction along the measurement axis direction. Such a configuration that shifts the positive and negative polarity detection loops in "pairs" (as compared to, for example, shifting the positive loop in the first direction and the negative loop in the opposite direction). May improve accuracy and robustness against misalignment. In some such embodiments, two respective pairs of adjacent loops at the opposite ends of each first set of sensing elements are along the measurement axis in each of those two pairs. It may be advantageous to have detection element effective regions of positive and negative loops shifted in the same direction (eg, as outlined with reference to FIG. 12).

The various embodiments of the first type described above operate on a "single track" scale having a single scale pattern track (eg, outlined below with reference to FIGS. 9, 10, 11, and 12). It may be configured to operate on a "two-track" scale having two scale pattern tracks (eg, outlined below with reference to FIG. 13). In various "two-track" embodiments, the scale pattern comprises signal modulation elements located on the first and second tracks extending along the measurement axis, and the magnetic field generation coil is located on the first track. It is configured to surround a first internal region portion to be aligned and a second internal region aligned with the second track. In such an embodiment, each sensing element set comprises at least one of features A1, B1, C1, and features D1 and / or E1, each comprising a first and second internal region portion. Defines first and second detection element effective region portions that extend across and in the measurement axis direction and correspond to portions of the sensing element that are aligned or overlap with the first and second internal region portions, respectively. It comprises a conductive loop, whereby the detection signal contributions generated in each conductive loop combine the contributions of the respective detection signals from its first and second detection element effective region portions.

In some of these two-track embodiments, the scale pattern is a signal modulation element or signal modulation element portion periodically arranged on the first track according to the wavelength W1 and a second scale pattern according to the wavelength W1. It is composed of a signal modulation element or a signal modulation element portion periodically arranged on the track, and the periodic arrangement of the first track and the second track is offset by (W1) / 2. It may be advantageous to use this configuration. The magnetic field generation coil is configured to generate a magnetic flux change of the first polarity in the first internal region portion and to generate a magnetic flux change of the opposite second polarity in the second internal region portion.

Of course, the various advantageous features outlined above can be used for each set of multiple sensing elements corresponding to each of the plurality of spatial phases in any encoder (eg, orthogonal, as outlined above). To provide a signal, or a three-phase signal). For example, in some such embodiments, the plurality of respective detection element sets corresponding to the plurality of respective spatial phases may each comprise at least features A1, B1, C1 and each of the plurality of detections. At least one of the element sets may further include at least feature E1. Such an embodiment thereby provides a potentially unwanted third-order spatial harmonic detection signal that can contribute to a determined relative position error between the detector and the scale pattern. It may be configured to provide a plurality of spatially filtered detection signals that can be used to reduce or suppress components and potentially unwanted K-order spatial harmonic detection signal components. In some such embodiments, each of the plurality of respective detection element sets has a region centroid of its entire detection element effective region located within its range along the measurement axis, and each of the plurality of detections. The device set may be configured such that the centers of gravity of their respective regions are nominally co-located along the measurement axis direction. With such a configuration, a specific misalignment error can be reliably eliminated, as described in detail below. In some such embodiments, the respective positive or negative loops included in any one of the plurality of respective detection element sets are included in the same one of the plurality of respective detection element sets. Each detection element effective region EffASEN that does not overlap with the detection element effective region EffASEN of each positive electrode or negative electrode loop is provided.

In various embodiments of the second type according to the principles disclosed herein (eg, shown in FIGS. 14-17), at least one respective set of sensing elements corresponding to each nominal spatial phase is: It comprises features A2 and B2 defined as.

A2) A plurality of positive loops corresponding to the first winding direction or polarity and the same number of negative loops corresponding to the second winding direction or polarity opposite to the first winding are provided.

B2) At least half of the positive loop and at least half of the negative loop have detection element effective regions arranged in a predetermined in-loop shift relationship with respect to each nominal spatial phase of each detection element set. It is configured as follows. In the loop shift relationship, in each such loop, the shift ratio in the loop up to half of the effective region of the detection element is measured in the first direction by (W1) / 4K in relation to the respective nominal spatial phase. The shift ratios in the loop, which are shifted along the axial direction and are nominally the same in the effective region of the detection element, are measured in the direction opposite to the first direction by (W1) / 4K in relation to the respective nominal spatial phases. It has a structure that shifts along. Thereby, the shift ratios in the two loops are shifted relative to each other by (W1) / 2K. K is one of 3, 5, 7, or 9.

As a result of implementing the above features (A2, B2), the detection element set corresponding to each nominal spatial phase can thereby cause a determined relative position error between the detector and the scale pattern. A practical configuration that provides a spatially filtered detection signal or multiple detection signals that can be used to reduce or suppress potentially unwanted K-order spatial harmonic detection signal components. It has become.

In some embodiments of the second type, in positive and negative loops configured by arranging the detection element effective regions in a predetermined intra-loop shift relationship, the intra-loop shift ratio is nominally their detection element. It may be half of the effective area. In some embodiments of the second type, it is particularly advantageous that all positive and negative loops are configured with their sensing element effective regions arranged in a predetermined intra-loop shift relationship. May be.

In some embodiments of the second type, at least each of the first sensing element sets is configured according to features A2 and B2 so that they have a nominally congruent shape with respect to their sensing element effective regions. At least the first pair of positive and negative loops configured in and at least the first pair of positive and negative loops configured to have a nominally congruent shape with respect to their detection element effective region. It comprises two pairs, the congruent shape in the first and second pairs is nominally a mirror image of each other, and the positive and negative loops of the first and second pairs are placed adjacent to each other. Will be done. Such a "mirror image pair" configuration may, in some embodiments, improve accuracy and / or robustness to a particular misalignment. In some such embodiments, each first set of sensing elements is configured to have a nominally congruent shape with respect to the effective region of the sensing element, at least within the first end pair. And at least the second of the positive and negative loops configured to have a nominally congruent shape with respect to at least the first end pair of the negative loop and the effective region of the detection element within the second end pair. It is advantageous that the pair of ends is provided and further configured to have a nominally congruent shape between the first pair of ends and the pair of second ends. It will be appreciated that the first and second end pairs are located at the first and second ends of the first set of sensing elements, respectively.

In some embodiments of the second type, is each sensing element included in each sensing element set configured to comprise features A2 and B2 aligned with one or more internal regions? Alternatively, it may have all overlapping effective detection element effective regions EffASEN, and may have an effective y-axis dimension EffYSEN along the y-axis direction, which is the sum of the dimensions of one or more internal regions orthogonal to the measurement axis direction. May be defined in. In various embodiments, at least half or more of such detectors are in the range of 0.33 * W1 ± 15%, along the measurement axis, as described in more detail below with respect to the various figures. It may be advantageous if it is configured to provide the average dimension DSENavg = (EffASEN / EffYSEN) of the detection element. In such various embodiments, K may be 5, 7, or 9. In such an embodiment, each detection element set configured to include features A2 and B2 can thereby contribute to a determined relative position error between the detector and the scale pattern. Spatial filtered, which can be used to reduce potential unwanted third-order spatial harmonic detection signal components and potential unwanted Kth-order spatial harmonic detection signal components. It is configured to provide a detection signal or a plurality of detection signals. In some such embodiments, K = 5 can be particularly advantageous. In some such embodiments, each positive or negative loop included in each set of detectors configured to comprise features A2 and B2 is included in each set of detectors. It may be configured to provide each detection element effective region EffASEN that does not overlap with the detection element effective region EffASEN of each positive or negative loop.

In some embodiments of the second type, at least each first set of sensing elements corresponding to their respective nominal spatial phases is configured according to features A2 and B2 and is characterized by a two-part configuration. And. The configuration consisting of the two parts is nominally aligned with the first separation part, which is composed of the same number of positive and negative loops, and the first separation part along the measurement axis direction. A second separation portion composed of the same number of positive electrode loops and negative electrode loops as the first separation portion is provided. The first separation part and the second separation part are separated by a gap located along the measurement axis direction between the first separation part and the second separation part, and the gap is separated in the measurement axis direction. Along it, it is at least as wide as one of the positive and negative loops, and the effective region of the positive loop or the effective region of the negative loop of each detection element set is not located within the gap. In some such embodiments, each of the first sets of sensing elements is configured such that the respective loops of its first and second separators closest to each other have the same loop polarity. In some such embodiments, the electromagnetic induction encoder has at least a second set of sensing elements corresponding to each nominal spatial phase 90 degrees different from the nominal spatial phase of each first sensing element set. Further provided, each of the second detection element sets is configured according to features A2 and B2, and is composed of two parts. The two-part configuration is composed of either two "adjacent parts" in some embodiments or two "separation parts" in other embodiments. In the following description, both cases will be described with reference to the alternative characteristics associated with the "separation" in parentheses. The configuration consisting of the two parts is nominally along the measurement axis direction with the first adjacent portion (separation portion) composed of the same number of positive electrode loops and negative electrode loops, and the first adjacent portion (separation portion). It is top-aligned and may include a second adjacent portion (separation portion) composed of the same number of positive electrode loops and negative electrode loops as the first adjacent portion (separation portion). The first and second adjacent portions (separations) are located closer to each other (away from each other) along the measurement axis direction than the width of one of the positive or negative loops, and are closest to each other. Each loop of the first and second adjacent portions (separations) has opposite loop polarities. Each of the first detection element sets has a first region center of gravity of the entire detection element effective region located between the first and second separation portions along the measurement axis, and each of the second detection elements. The element set has a second region center of gravity of the entire detection element effective region located between its first and second adjacent portions (separations) along the measurement axis. In some such embodiments, the first and second detection element sets may have their respective first and second region centroids co-located along the measurement axis direction. Such center-of-gravity embodiments offer some advantage in eliminating certain errors due to "pitch" shifts between the detector and the scale pattern, while at the same time economical layout and manufacturing. Can be facilitated. In some such embodiments, the respective positive or negative loops contained in one of the first or second sets of detectors are included in the same one of the first or second sets of detectors. It is configured to provide each detection element effective region EffASEN that does not overlap with the detection element effective region EffASEN of each of the other positive or negative loops.

As outlined above, in various embodiments of the second type that include two flanking sections, or two separating sections, the electromagnetic induction encoder may be configured according to either M1 or M2. M1) The first adjacent (or separated) unit is configured to output the first detection signal, the second adjacent (or separated) unit is configured to output the second detection signal, and signal processing. The unit is configured to determine the relative position between the detector and the scale pattern, at least partially based on the combination of the first and second signals. Alternatively, M2) the first adjacent (or separated) part is connected in series with the second adjacent (or separated) part to form a composite signal, and the series connection is the first and second parts of the composite signal. Each signal contribution is configured to be added, and the signal processor is configured to determine the relative position between the detector and the scale pattern, at least partially based on the composite signal. When the adjacencies are connected in series, the first and second adjacencies can, in some embodiments, be interpreted as part of a continuous, uninterrupted set of sensing elements.

The various embodiments of the second type described above are to operate on a "single track" scale having a single scale pattern track (eg, outlined below with reference to FIGS. 14, 15, and 16). It may be configured to operate on a "two-track" scale having two scale pattern tracks (eg, outlined below with reference to FIG. 17). In various "two-track" second type embodiments, the scale pattern comprises signal modulation elements located on the first and second tracks extending along the measurement axis, and the magnetic field generation coil is the first. It is configured to surround a first internal region portion aligned with one track and a second internal region aligned with the second track. In such an embodiment, each sensing element set comprises features A2 and B2, each extending across the first and second internal region portions in the measurement axis direction, respectively, of the first and second. Conductive loops may be provided that define first and second detection element effective region portions that correspond to portions of the sensing element that are aligned or overlap with the internal region portion. The contribution of the detection signal generated in each conductive loop combines the contribution of the respective detection signal from the first and second detection element effective region portions.

In some of these two-track second-type embodiments, the scale pattern is a signal-modulating element or signal-modulating element portion periodically arranged on the first track according to wavelength W1 and wavelength W1. It is composed of a signal modulation element or a signal modulation element portion periodically arranged on the second track according to the above, and the periodic arrangement of the first track and the second track is relative to (W1) / 2. It may be advantageous to use a configuration that is offset. The magnetic field generation coil is configured to generate a magnetic flux change of the first polarity in the first internal region portion and to generate a magnetic flux change of the opposite second polarity in the second internal region portion.

As described above and described in more detail below with respect to the various figures, many different embodiments of the second type include each conductive loop or conductivity included in each detection element set with features A2 and B2. The loop portion is configured to include a respective detection element effective region EffASEN that does not overlap with another conductive loop or other respective detection element effective region EffASEN included in the same respective detection element set. You may. This is considered to be particularly advantageous in order to facilitate economical layout and manufacturing in some embodiments of the second type, and at the same time, as outlined above and described in more detail below. Provides a relatively ideal combination of spatially filtered detection signals and suppression of misalignment errors. Conventional techniques do not provide a comparable combination of functionality and performance.

Of course, any of the second types of embodiments outlined above can be used in any encoder for a plurality of respective detection element sets corresponding to a plurality of respective spatial phases, as outlined above. Can (eg, to provide orthogonal signals, or three-phase signals). In such an embodiment, each of the plurality of respective detection element sets corresponding to the plurality of respective spatial phases is configured to include features A2) and B2), whereby the detection unit and the scale are provided. Spatial, which can be used to reduce or suppress potentially unwanted K-th order spatial harmonic detection signal components that can contribute to the determined relative positional error with and from the pattern. Is configured to provide a filtered detection signal. In some such embodiments, each of the plurality of respective detection element sets has a region centroid of its entire detection element effective region located within its range along the measurement axis, and each of the plurality of detections. The element set is configured such that the centers of gravity of their respective regions are aligned at the same location along the measurement axis direction. This may be beneficial in reducing certain misalignment errors that may occur in other ways, as outlined above and described in more detail below. As shown above, in some such embodiments, each conductive loop or conductive loop portion included in each detection element set comprising features A2 and B2 is the same respective detection element set. Each detection element effective region EffASEN that does not overlap with each other detection element effective region EffASEN included in the other conductive loop or the conductive loop portion may be provided. In some such embodiments, each detection element included in each of the plurality of detection element sets has a full detection element effective region EffASEN that is aligned with the internal region or overlaps with one or more internal regions. Detection that is defined to have an effective y-axis dimension EffYSEN along the y-axis direction, which is the sum of the dimensions of one or more internal regions perpendicular to the measurement axis direction, and is included in each of the plurality of detection element sets. At least half of the elements are configured so that the average dimension DSENavg = (EffASEN / EffYSEN) of the detection element along the measurement axis direction is within the range of 0.33 * W1 ± 15%. Thereby, the electromagnetic induction encoder has a potential unwanted third-order spatial harmonic detection signal component that can contribute to a determined relative position error between the detector and the scale pattern. And are configured to provide a plurality of spatially filtered detection signals that can be used to reduce or suppress potentially unwanted K-order spatial harmonic detection signal components.

It is an assembly disassembly isometric view of a hand tool type caliper using an electromagnetic induction type encoder including a detection part and a scale. FIG. 5 is a plan view schematically showing a specific feature of a typical prior art electromagnetic induction encoder presented as background information related to various principles disclosed herein. FIG. 1 is a plan view of an embodiment of a detection unit and a scale pattern that can be used in an electromagnetic induction encoder as shown in FIG. 1, and a signal modulation element based on the principle disclosed in the present specification is disclosed in the present specification. It is shown in combination with known "less desirable" sensing elements, along with various dimensions that can characterize their characteristics by principle. FIG. 3 is an enlarged isometric view of a portion of the detector and scale pattern shown in FIG. 3 and includes a qualitative representation of magnetic flux and magnetic flux coupling characteristics that may be associated with the operation of the signal modulation element in the electromagnetic induction encoder. Implementation of each signal modulation element and detection element similar to those shown in FIG. 3, including additional examples of specific exemplary dimensions capable of characterizing their features according to the principles disclosed herein. It is a top view schematically showing a specific aspect of a form. Implementation of each signal modulation element and detection element similar to those shown in FIG. 3, including additional examples of specific exemplary dimensions capable of characterizing their features according to the principles disclosed herein. It is a top view schematically showing a specific aspect of a form. It is compatible with the detection element configuration principles disclosed herein with reference to FIGS. 9-12 and is suitable for use in the detector and scale patterns of electromagnetic induction encoders as shown in FIG. FIG. 5 is a plan view showing various embodiments of detector elements and scale patterns, along with examples of various dimensions that may characterize their characteristics. It is compatible with the detection element configuration principles disclosed herein with reference to FIGS. 9-12 and is suitable for use in the detector and scale patterns of electromagnetic induction encoders as shown in FIG. FIG. 5 is a plan view showing various embodiments of detector elements and scale patterns, along with examples of various dimensions that may characterize their characteristics. It is compatible with the detection element configuration principles disclosed herein with reference to FIGS. 9-12 and is suitable for use in the detector and scale patterns of electromagnetic induction encoders as shown in FIG. FIG. 5 is a plan view showing various embodiments of detector elements and scale patterns, along with examples of various dimensions that may characterize their characteristics. According to the predetermined relational principle of the first type disclosed herein to provide a spatially filtered signal for use in the detector of an electromagnetic induction encoder as shown in FIG. A first compatible magnetic field generation coil and scale pattern on a particular aspect of the first detection element set corresponding to the first spatial phase, which is the first exemplary configuration of the configured detection element set. It is a plan view including various dimensions that characterize the detection element configuration according to the principle disclosed in this specification. Specific aspects of the second detection element set corresponding to the second spatial phase configured similar to the first detection element shown in FIG. 9 of the first detection element set shown in FIG. It is a plan view which is superposed on the ghosted expression, and shows the operation quadrature configuration which the spatial phase of the 1st and 2nd detection element sets is different by 90 degrees. A second detection element set corresponding to a second spatial phase, which is a second exemplary configuration of a detection element set configured according to a predetermined relational principle of the first type disclosed herein. It is a top view which shows a certain side surface together with the 1st detection element set shown in FIG. For illustration purposes, the first and second detector sets are to better show the individual characteristics and their relative alignment along the measurement axis in an operating quadrature configuration where the spatial phases differ by 90 degrees. The second set is offset from each other along the vertical direction in FIG. 11A. A first detection element set corresponding to a first spatial phase, which is a third exemplary configuration of a detection element set configured according to a predetermined relational principle of the first type disclosed herein. It is a top view which shows a specific side surface together with the 2nd detection element set shown in FIG. 11A. For illustration purposes, the first and second detector sets are to better show the individual characteristics and their relative alignment along the measurement axis in an operating quadrature configuration where the spatial phases differ by 90 degrees. The second set is offset from each other along the vertical direction in FIG. 11B. The first and second corresponding spatial phases, which are the fourth and fifth exemplary configurations of the sensing element set configured according to the predetermined relational principle of the first type disclosed herein. It is a top view which shows the specific side surface of the detection element set of. For illustration purposes, the first and second detector sets are to better show the individual characteristics and their relative alignment along the measurement axis in an operating quadrature configuration where the spatial phases differ by 90 degrees. The second set is offset from each other along the vertical direction in FIG. According to the predetermined relational principle of the first type disclosed herein to provide a spatially filtered signal for use in the detector of an electromagnetic induction encoder as shown in FIG. A second compatible magnetic field generation coil and scale pattern on a particular aspect of the first detection element set corresponding to the first spatial phase, which is the sixth exemplary configuration of the configured detection element set. It is a plan view including various dimensions that characterize the detection element configuration according to the principle disclosed in this specification. According to the predetermined relational principle of the second type disclosed herein to provide a spatially filtered signal for use in the detector of an electromagnetic induction encoder as shown in FIG. A side of the first detection element set corresponding to the first spatial phase, which is the first exemplary configuration of the configured detection element set, is exposed to a first compatible magnetic field shown in FIG. FIG. 5 is a plan view including a generation coil and a scale pattern, as well as various dimensions that characterize the detection element configuration according to the principles disclosed herein. According to the predetermined relational principle of the second type disclosed herein to provide a spatially filtered signal for use in the detector of an electromagnetic induction encoder as shown in FIG. A particular aspect of the first detection element set corresponding to the first spatial phase, which is the second exemplary configuration of the configured detection element set, is the first compatibility shown in FIGS. 9 and 14. It is a plan view which includes a magnetic field generation coil and a scale pattern, and various dimensions which characterize the detection element composition by the principle disclosed in this specification. A second detection element set corresponding to a second spatial phase, which is a third exemplary configuration of a detection element set configured according to a predetermined relational principle of the second type disclosed herein. It is a top view which shows a certain side surface together with the 1st detection element set shown in FIG. For illustration purposes, the first and second detector sets are to better show the individual characteristics and their relative alignment along the measurement axis in an operating quadrature configuration where the spatial phases differ by 90 degrees. The second set is offset from each other along the vertical direction in FIG. According to the predetermined relational principle of the second type disclosed herein to provide a spatially filtered signal for use in the detector of an electromagnetic induction encoder as shown in FIG. A particular aspect of the first detection element set corresponding to the first spatial phase, which is the fourth exemplary configuration of the configured detection element set, is the second compatible aspect shown in FIG. FIG. 5 is a plan view including a magnetic field generation coil and a scale pattern, as well as various dimensions that characterize the detection element configuration according to the principles disclosed herein.

FIG. 1 is an assembled and disassembled isometric view of a hand tool type caliper 100 including a scale member 172 and a slider assembly 120. The scale member 172 may include a main scale having a substantially rectangular cross section, including a scale 170 arranged in the groove. The slider assembly 120 can include a base 140, an electronic assembly 160, and a cover 150, which are described in more detail below. The electronic assembly 160 can include a detection unit 167 and a signal processing unit 166 arranged on the substrate 162. An elastic seal (not shown) may be compressed between the cover 150 and the substrate 162 to remove dirt from the electronics and connections. The scale 170, the detection unit 167, and the signal processing unit 166 work together to measure the relative position between the two elements (eg, between the scale member 172 and the slider assembly 120) along the measurement axis direction MA. Acts to provide an electromagnetic induction encoder that can be used for.

In various embodiments, the scale 170 extends along the measurement axial MA (eg, corresponding to the x-axis direction) and is created on the scale substrate (eg, using known printed circuit manufacturing methods). The signal modulation scale pattern 180 including the signal modulation element SME is included. In the various embodiments presented herein, the signal modulation scale pattern 180 may optionally be referred to as the periodic scale pattern 180, which is shown in FIG. 1 to have the spatial wavelength W1. In the illustrated embodiment, a known type of cover layer 174 (eg, 100 μm thick) covers the scale 170 (as shown cut out in FIG. 1).

In various embodiments, the mechanical structure and operation of Nogis 100 is commonly assigned US Pat. No. 5,901,458, and / or US Pat. No. 6,400,138, and / or US Reissue. It may be similar to that of a particular conventional electronic nogis, such as that of Japanese Patent No. 37490, each of which is incorporated herein by reference in its entirety. Jaw 176 and 178 near the first end of the scale member 172, as well as movable jaws 146 and 148 on the slider assembly 120, are used to dimension the object in a known manner. The measured dimensions can be displayed on a digital display 158 mounted within the cover 150 of the electronic assembly 160. The cover 150 can also include an on / off switch 154 and, optionally, other optional control buttons that activate the circuits or elements contained in the electronic assembly 160. The base 140 of the slider assembly 120 guides the slider assembly 120 along the mating edge of the scale member 172 to ensure proper alignment for measurement while moving the slider assembly 120 with respect to the scale 170. It may contain various known elements configured as such.

As shown in FIG. 1, the detection unit 167 can include a magnetic field generation coil FGC and a detection element set SETSEN arranged along the measurement axial direction MA. In one particular exemplary example, the detector 167 may be arranged parallel to the scale 170 and facing the scale 170, with the front surface of the detector 167 facing the scale 170 along the Z-axis direction. It may be separated from the scale 170 (and / or the scale pattern 180) by a gap of about 0.5 mm. The front surface of the detector 167 (eg, its constituent conductors) may be covered with an insulating coating. The structure and operation of the magnetic field generation coil FGC and the detection element set SETSEN will be described in more detail below.

The Nogis 100 shown in FIG. 1 offers a relatively optimized combination of compact size, low power operation (eg, due to long battery life), high resolution and precision measurements, low cost, and stain robustness. In order to do so, it will be understood that it is one of a variety of applications that typically implements electromagnetic induction encoders that have evolved over the years. Other applications that are perhaps even more difficult, for example, in terms of advanced precision improvements, cost-effective design and manufacturing, include medium-precision and high-precision digital "dial" indicators (these are, for example, respectively). Provides precision on the order of 10 micrometers and 1 micrometer). Even the slightest improvement in any of these factors in any of these applications is highly desirable, but especially in view of the design constraints imposed to achieve commercial success in a variety of applications. Is difficult to achieve. The principles disclosed and claimed herein provide improvements in many of these factors for a variety of applications.

FIG. 2 is a specific specification of a representative prior art electromagnetic induction encoder set forth in Japanese Patent No. '389, presented as background information relating to various principles disclosed elsewhere herein. It is a top view which shows the feature roughly. FIG. 2 further includes a reference number to indicate an equivalent reference number or symbol used to indicate an equivalent element in the other figures contained herein. In the following abbreviated description based on the disclosure of patent '389, the equivalent reference number in the other figures of the present disclosure is shown in parentheses following the original reference number from patent '389. A complete description of FIG. 2 of the prior art can be found in patent '389. Therefore, only abbreviated explanations, including teachings from patent '389, which are relevant to this disclosure, are included herein. As far as the inventor can confirm, the teachings outlined below with reference to FIG. 2 are the conventional theories known in the art and / or used in commercially available electromagnetic induction encoders and Represents a conventional design method.

As disclosed in Japanese Patent No. 389, a transducer as shown in FIG. 2 includes at least two substantially coplanar paths of wire or winding. The transmit winding 102 (FGC) forms a large planar loop. The receiving winding 104 (SETSEN), which is substantially coplanar with the transmitting winding 102, is arranged in one direction as indicated by the arrows in a zigzag or sinusoidal pattern, and then the windings are indicated by the arrows. They form loops 106 (SEN +) and 108 (SEN−) that are arranged in opposite directions across themselves and alternate between each other. As a result, each of the alternating loops 106 (SEN +) and 108 (SEN−) of the receiving winding 104 (SETSEN) has a different winding direction or polarity as compared to the adjacent loop. By applying an alternating current (changing) current to the transmit winding 102 (FGC), the transmit winding changes over time through loops 106 (SEN +) and 108 (SEN−) of the receive winding 104 (SETSEN). Generates a magnetic field.

A scale or scale pattern 112 (180) containing a conductive object (eg, a conductive plate 114 (SME), some of which are outlined using short dots on the scale pattern 112 in FIG. 2). When (the segment is outlined in FIG. 2 by edges showing alternating long and short dots) is moved closer to the transducer, the fluctuating magnetic field generated by the transmit winding 102 (FGC) , Inducing an eddy current into the conductive object, which in turn creates a magnetic field from the conductive object that counteracts fluctuations in the transmitter magnetic field, so that the magnetic field received by the receiving winding 104 (SETSEN) changes or Disturbed, thereby causing the receiving winding to output a non-zero EMF signal (voltage) at the output terminals V + and V- of the receiving winding 104, which is a positive "+" loop 106 (SEN +) of the conductive object. ) And the negative “−” loop 108 (SEN−), the polarity is changed as it moves.

In this prior art example, the distance between the positions of two loops of the same polarity (eg, between the position of loop 106 (SEN +) and the position of the next loop 106 (SEN +)) is the transducer pitch or wavelength 110. Defined as (W1). Therefore, it will be found that each loop 106 (SEN +) and / or 108 (SEN−) has a length or maximum dimension of 0.5 * W1 along the measurement axis direction 300. When the above-mentioned conductive object (for example, the conductive plate 114 (SME)) is close to the receiving winding 104 (SETSEN) and continuously changes at a position along the measurement axis 300 (MA), the receiving winding (eg, the receiving winding (SME)). The AC amplitude of the signal output from the SETSEN) is the periodic change in polarity of loops 106 (SEN) and 108 (SEN), as well as the transmission magnetic field caused by the conductive object (eg, the conductive plate 114 (SME)). Due to the local disturbance of, it changes continuously and periodically at the wavelength 110 (W1).

The '389 patent states that when a conductive object (eg, conductive plate 114 (SME)) is much smaller or larger than loop 106 and / or 108 (SEN +, SEN-), the amplitude of the signal output is weak. Emphasizes that it is difficult to obtain high accuracy. If the conductive object (eg, conductive plate 114 (SME)) has a length equal to about half the wavelength 110 (W1) (ie, the object exactly matches loop 106 or 108 (SEN + or SEN-)). The signal output has a large amplitude and is therefore most sensitive to the position of the conductive object. Therefore, the present disclosure (as described in Patent No. '389) preferably has a length equal to half the wavelength 110 (W1) (along the x-axis direction) (eg, a conductive plate 114). (SME)) is used.

The transmit winding 102 and the receive winding 104 (SETSEN) shown in FIG. 2 and described above are prior art of the element designated as the detection unit in the present specification (for example, the detection unit 167 shown in FIG. 1). An example of an example, scale or scale pattern 112 (180) is an example of a prior art embodiment shown herein as a scale pattern (eg, scale pattern 180 shown in FIG. 1).

FIG. 3 is a plan view of an embodiment of a detection unit 367 and a scale pattern 380 that can be used in an electromagnetic induction encoder as shown in FIG. For clarity of explanation, it is shown in combination with the conventionally known "less desirable" known detection element SEN. In addition, FIG. 3 introduces various dimensions that can characterize the characteristics of the signal modulation element SME and the detection element SEN according to the principles disclosed herein. The size and shape of the more preferred detection element SEN according to the principles disclosed herein will be described in more detail below with reference to FIGS. 6, 7, and 8. Refer to FIGS. 9-13 and 14-17 for desirable alternative configurations and / or predetermined relationships for determining the position and / or shape of the detector SEN according to the principles disclosed herein. This will be further described below.

Various features of the detector 367 and scale pattern 380 are configured to meet the various design principles disclosed and claimed herein, especially with respect to the signal modulation element SME. The several numbered components 3XX of FIG. 3 correspond to the similarly numbered components 1XX of FIGS. 1 and / or 2 and may provide / or provide similar behavior or functionality. It is understood that, for example, the detection unit 367 provides the same operation or function as the detection unit 167 and can be understood in the same manner unless otherwise instructed.

FIG. 3 can be regarded as partly concrete and partly schematic. An enlarged portion of the detection unit 367 and the scale pattern 380 is shown at the bottom of FIG. In FIG. 3, the various elements described below are represented by their shape or contour and are shown superimposed on top of each other to emphasize a particular geometric relationship. As will be apparent to those skilled in the art based on the following description and cited references, various located in different planes along the z-axis, as needed, to provide various operating gaps and / or insulating layers. It will be understood that various elements may be present on various processed layers. Throughout the drawings of the present disclosure, the illustrated x-axis, y-axis, and / or z-axis dimensions of one or more elements may be exaggerated for clarity, but they are described herein. It will be appreciated that it is not intended to be inconsistent with the various dimensional design principles and relationships disclosed and claimed in writing.

The illustrated portion of the scale pattern 380 includes a first type of signal modulation element SME that is dot-painted and outlined with a dashed line. The periodic scale pattern 380 has a spatial wavelength W1. In this embodiment, the first type of signal modulation element SME is such that (eg, formed by regions manufactured on a printed circuit board, or by raised regions extending from a conductive substrate). It is equipped with a plurality of conductive plates. However, in other embodiments, they can include multiple conductive loops (eg, formed by traces on a printed circuit board), as described in more detail below. In either case, it is arranged along the measurement axial direction MA corresponding to the spatial wavelength W1. The scale pattern 380 is generally mounted on a scale (eg, scale 170 shown in FIG. 1). In the embodiment shown in FIG. 3, the y-direction end of most signal modulator SMEs is as described in (eg, '335, '943, and '199 patents. ,) Hidden under the first extension EP1 and the second extension EP2 of the magnetic field generation coil FGC. As shown in FIG. 1, it will be understood that the scale pattern 380 moves relative to the detector 367 during operation.

In the example of FIG. 3, the scale pattern 380 has a nominal scale pattern width dimension NSPWD along the y-axis direction and is periodically (eg, corresponding to the x-axis direction) arranged along the measurement axis direction MA. It also includes a substantially rectangular signal modulation element SME. However, more generally, the scale pattern 380 has a spatial characteristic in which the pattern changes as a function of the position along the x-axis direction, and the detection element SEN (for example, SEN14) of the detection element set SETSEN in the detection unit 367. ) Can include various alternative spatial modulation patterns, including alternative signal modulation element configurations, provided that the position-dependent detection signal (also referred to as the detection signal component in some embodiments) is provided. ..

In various embodiments, the detector 367 is mounted in close proximity to the scale pattern 380 and is configured to move along the measurement axial direction MA with respect to the scale pattern 380. As will be appreciated by those skilled in the art, the detector is a set of detectors capable of taking various alternative configurations used in combination with the magnetic field generation coil FGC and various corresponding signal processing schemes in various embodiments. Includes with SETSEN. FIG. 3 shows a single representative set of detection elements SEN1 to SEN24, which in this embodiment are referred to as detection loop elements (or detection coil elements or detection winding elements) connected in series. To be equipped. In this embodiment, adjacent loop elements are connected by the configuration of conductors on various layers of the PCB (eg, connected by feedthrough) and opposite according to known methods (eg, as shown in FIG. 4). It is connected so as to have the winding polarity of. That is, when the first loop responds to the change in the magnetic field with a positive detection signal contribution, the adjacent loop responds with a negative detection signal contribution. Loops with positive detection signal contributions can be referred to herein as SEN + detection elements, and loops with negative detection signal contributions are referred to herein as SEN-detection elements. Can be done. In this embodiment, the detection elements are connected in series so that their detection signals or signal contributions are added, and the "added" detection signals are signaled by the detection signal output connections SDS1 and SDS2 (shown). Is output to.

FIG. 3 shows a set of detectors to avoid visual confusion, but in various embodiments, one or more additional detectors (eg, similar to SETSEN) at different spatial phase positions. Those skilled in the art will appreciate that it is advantageous to configure the detector to provide a set of elements (eg, to provide an orthogonal signal). However, it should be understood that the configuration of the detection element described herein is merely exemplary and not limiting. As an example, loops of individual detectors output individual signals to the corresponding signal processor in some embodiments, as disclosed, for example, in US Pat. No. 9,958,294. can do. More generally, the configurations of various known sensing devices for use in combination with various known scale patterns and signal processing schemes are combined with the principles disclosed and claimed herein. It can be used in various embodiments.

Various members of the detection element set SETSEN and the set of magnetic field generation coil FGC may be fixed on a substrate (eg, substrate 162 in FIG. 1). The magnetic field generation coil FGC can be described as enclosing an internal region INTA having a nominal coil area length dimension NCALD along the x-axis direction and a nominal coil area width dimension of about YSEP along the y-axis direction. .. The internal region INTA is aligned with the periodic scale pattern 380 of the signal modulation element SME during operation, as approximately illustrated. In the illustrated embodiment, the magnetic field generation coil FGC comprises a single winding surrounding the internal region INTA. However, in various other embodiments, the magnetic field generation coil FGC can include multiple turns and / or meander to operably surround the internal region INTA aligned with the scale pattern 380 (eg,). As disclosed in the bibliography, operably encloses other internal areas aligned with the scale track containing other scale patterns (eg, operably enclosing). Surrounding). In any case, during operation, the magnetic field generation coil FGC generates a magnetic flux change in the internal region INTA in response to the coil drive signal. In the illustrated embodiment, the first connection portion CP1 and the second connection portion CP2 are used to connect the coil drive signal from the signal processing unit (for example, the signal processing unit 166 in FIG. 1) to the magnetic field generation coil FGC. can do.

The detection element set SETSEN (for example, a set of detection elements SEN1 to SEN24) is arranged along the x-axis direction (for example, corresponding to the measurement axis direction MA) and fixed on the substrate (for example, the substrate 162 in FIG. 1). Will be done. As shown in FIG. 3, the members of the detection element set are aligned with the internal region INTA surrounded by the magnetic field generation coil FGC, or the portion of the detection element that overlaps the internal region INTA (that is, of the detection elements). It is composed of a conductive loop or a conductive loop portion (for example, SEN1 to SEN24) that defines the detection element effective region EffASEN corresponding to the portion that is aligned with or overlaps the INTA dimension YSEP. In various embodiments, the detection element effective region EffASEN, which is aligned with or overlaps the internal region INTA, has an effective y-axis dimension EffYSEN along the y-axis direction orthogonal to the measurement axis direction and a measurement axis direction (x-axis direction). ), And can be described as having the maximum dimension DSENmax. In the particular embodiment shown in FIG. 3, the effective y-axis dimension EffYSEN is equal to YSEP. This is because each of the detection elements SEN has a maximum detection element dimension YSENMAX along the y-axis direction that exceeds YSEP, and therefore its effective region EffASEN covers the entire dimension YSEP. The maximum dimension DSENmax in the measurement axis direction is nominally 0.5 * W1. However, these features are specific to this embodiment and are not limiting, as will be described in more detail below with reference to FIGS. 5B, 6, 7, and 8. In various embodiments, it may be of arbitrary choice (or undesired).

It is useful to further characterize the detection element effective region EffASEN by the detection element average dimension SENavg = (EffASEN / EffYSEN) along the measurement axis direction. In the particular embodiment shown in FIG. 3, since the detection element effective region EffASEN has parallel sides perpendicular to the x-axis direction, DSENavg is equal to DRENmax. However, this does not have to be the case in all embodiments, as described in detail below with reference to FIGS. 5B, 6, 7, and 8.

The detection element of the detection element set SETSEN provides a detection signal according to the local influence on the magnetic flux change provided by the adjacent signal modulation element SME (for example, one or more signal modulation element SMEs) of the scale pattern 380. It is configured as follows. The signal processing unit (for example, the signal processing unit 166 in FIG. 1) may be configured to determine the position of the detection element set SETSEN with respect to the scale pattern 380 based on the detection signal input from the detection unit 367. .. In general, the magnetic field generation coil FGC, the sensing element set SETSEN, and the like may operate according to known principles (eg, electromagnetic induction encoders) as described in the references.

In various embodiments, the magnetic field generation coil FGC and the sensing element SEN are isolated from each other (eg, as arranged on different layers of a printed circuit board). In such one embodiment, it is advantageous that the maximum y-axis direction detection element dimension YSENMAX of the detection element SEN is larger than the nominal coil area width dimension YSEP, and the extension portion EP1 or EP2 is increased by the amount defined as the overlap dimension. Extends beyond the inner edge of. Further, the magnetic field generation coil FGC may be advantageously configured such that the trace widths of the extension portions EP1 and EP2 along the y-axis direction are larger than the corresponding overlapping dimensions. In various embodiments, the extension parts EP1 and EP2 can be manufactured on the first layer of the printed circuit board, and the detection element SEN has a layer different from the first layer, at least in the vicinity of the overlap dimension. Included Conductive loops made within one or more layers of the printed circuit board can be included. However, such embodiments are exemplary and are not limiting, as will be further described below.

As shown above, in some embodiments, the magnetic field generation coil FGC can include one or more conductive traces made on a printed circuit board and the detection element SEN of the detection element set SETSEN. Can include a magnetic flux detection loop or loop portion formed by a conductive trace made on a printed circuit board. As mentioned above with respect to FIG. 1, in various embodiments, the detector 367 may be included in various types of measuring instruments (eg, calipers, micrometer, gauges, linear scales, etc.). For example, the detection unit 367 may be fixed to the slide member, and the scale pattern 380 may be fixed to a handle or a main scale whose measurement axis coincides with the x-axis direction. In such a configuration, the slide member is movably mounted on the beam or girder member and is movable along the measurement axial MA in a plane extending along the x-axis and y-axis directions. The z-axis direction is orthogonal to the plane.

With respect to the enlarged cross-section of the detector 367 and scale pattern 380 shown at the bottom of FIG. 3, it is the three exemplary detectors SEN14, SEN15, and SEN15 of the detector set SETSEN, bounded by a portion of the magnetic field generation coil FGC. SEN16 and two exemplary signal modulation elements SMEs are shown. In this embodiment, the detection element can be formed by a trace manufactured on the first and second layers of the circuit board with a layer of insulator sandwiched between them. The "first layer" trace is shown as a solid line and the "second layer" trace is shown as a dashed line. The small arrows indicate the direction of the current induced in the trace by the change in magnetic field generated from the magnetic field generation coil FGC. The sensing element SEN14 can be characterized as a "SEN +" positive loop due to its associated current direction, and the adjacent sensing element SEN15 is "SEN-" negative due to its associated "opposite polarity" current direction. It turns out that it can be characterized as a loop. The next adjacent detection element SEN16 may again be characterized as a "SEN +" positive loop, and so on.

The DSME is an average dimension along the measurement axis MA of the "effective domain" EffRSME of the (first type) signal modulation element SME. The effective region EffRSME of the signal modulation element SME is here aligned with or overlaps the y-axis dimension of the internal region INTA. The effective domain EffRSME produces a primary signal modulation effect in the detection element SEN. In the example shown in FIG. 3, it can be seen that this is the portion of the signal modulation element SME that coincides with the span of dimension YSEP along the y-axis direction. In various embodiments, the average dimension DSME of the signal modulation element SME can be considered to be the area of the effective region EffRSME of the signal modulation element SME divided by the y-axis dimension of the effective region EffRSME. Further examples of dimensional DSMEs for other configurations of the signal modulator SME are shown in FIGS. 5A, 5B, 6, 7, and 8.

As outlined above with reference to FIG. 2, a detection element such as the detection element SEN has conventionally been used to have a maximum dimension DSENmax along the measurement axis direction of 0.5 * W1. Such dimensions can be advantageous in various embodiments. Further, as described above with reference to FIG. 2, it has been conventionally practiced that a signal modulation element such as the signal modulation element SME has an average width dimension DSME of 0.5 * W1. Contrary to the conventional design method of the prior art described above, the present inventor is configured such that the signal modulation element SME has an average width dimension DSME significantly larger than 0.5 * W1 as shown in FIG. If so, we have found that certain performance characteristics may be improved. For example, in some embodiments, it may be advantageous if the DSPE is at least 0.55 * W1 and at most 0.8 * DSEN. In some such embodiments, it may be advantageous if the DSPE is at least 0.66 * W1, or 0.7 * W1 or higher. The reason will be described later with reference to FIG.

In addition, the inventor has an average dimension DSENavg of 0.5 * W1 for the detection elements in order to obtain the highest accuracy in various applications in order to mitigate certain errors that would otherwise appear. It has been further found that it is most desirable to use it in combination with a non-conventional detection element SEN configured to fall within a significantly smaller range. For example, in various embodiments, it is desirable that the average dimension DSENavg of the detection element is at least 0.285 * W1 and at most 0.315 * W1. This aspect of the invention will be described in more detail below with reference to FIGS. 6, 7, and 8. The combination of non-conventional features as described above provides advantageous detection signal characteristics compared to configurations based on prior art design principles (eg, better signal-to-noise (S / N) ratios). And / or reduce the error component in the detection signal).

FIG. 4 is a portion of the detector 367 and scale pattern 380 shown in FIG. 3, including a qualitative representation of the magnetic flux and magnetic flux coupling characteristics that may be associated with the operation of the signal modulation element SME in such an electromagnetic induction encoder. It is an enlarged isometric view. FIG. 4 shows, in various embodiments, it is advantageous that the signal modulation element SME is configured to have an average width dimension DSME of at least 0.55 * W1 and at most 0.8 * W1. It presents various considerations related to the possible reasons.

FIG. 4 shows the response of the signal modulation element SME to the generated changing magnetic field GCMF provided by the magnetic field generating coil FGC, as outlined above. As shown in FIG. 4, the coil drive signal current Igen applied to the magnetic field generation coil FGC generates a changing magnetic field GCMF that is inductively coupled to the signal modulation element SME. The signal modulation element SME is schematically shown as a conductive loop in FIG. 4, in response to a coupled changing magnetic field GCMF, an induced current Iind is generated in the signal modulation element SME, which is a magnetic flux line. Generates an induced magnetic field represented by (magnetic flux lines including the arrow in FIG. 4). The illustrated magnetic flux lines are the central magnetic flux CF represented by the central magnetic flux line CFL and the peripheral magnetic flux lines MFL1 to MFL3 shown to surround the conductive loop of the signal modulation element SME. Represents the magnetic flux MF of.

Generally speaking, it will be appreciated that the sensing elements of the sensing element set SETSEN generate signals (or signal contributions) in response to the induced magnetic flux changes represented as outlined above. In particular, the generated signal produces a signal contribution or signal component represented as a current sense in the detection element SEN14 of FIG. 4 in response to the amount of magnetic flux effectively coupled through its internal loop region. .. As shown in FIG. 4, in various embodiments, the detector 367 and the scale pattern 380 may be substantially planar (eg, they may include a substantially planar substrate or be formed on a substantially planar substrate). The detection unit 367 may be configured to be mounted substantially parallel to the periodic scale pattern 380 and with a nominal operating gap GapZ between the conductors. For example, in various embodiments, the nominal operating gap GapZ can be at least 0.075 * W1 to facilitate actual assembly and alignment tolerances. In some such embodiments, the nominal operating gap may be at least 0.15 * W1. As shown in FIG. 4, the central magnetic flux CF is generally effectively coupled via the detection element SEN 14 over a practical range of operating gaps. However, due to the operating gap, at least a portion of the peripheral magnetic flux MF may not be effectively coupled via the detection element SEN14. For example, as exaggerated in FIG. 4, in the relatively large size of the operating gap GapZ, none of the peripheral magnetic flux lines MFL1 to MFL3 are coupled via the detection element SEN14 and do not contribute to the current sense. As a result, in the configuration qualitatively shown in FIG. 4, the effective width Weff (indicated by the broken line in FIG. 4) of the signal modulation element SME detected by the detection element SEN14 is limited to the coupled central magnetic flux line CFL only. handle. As can be seen from FIG. 4, for example, even if the operating gap GapZ is reduced in order to couple the peripheral magnetic flux lines MFL3 via the detection element SEN14, the effective width Weff is higher than the average dimension DSME of the signal modulation element SME. Also remains small.

Therefore, contrary to the teachings of the prior art outlined above with reference to FIG. 2, it is advantageous for the signal modulation element SME to have an average dimension DSME larger than the desired effective width Weff, thereby the measurement axis. It produces the desired maximum signal variation and / or the desired signal profile pair displacement as it passes through the sensing element SEN along the direction. For example, in some embodiments, it may be desirable for the dimension Weff to be about 0.5 * W1, which, according to the aforementioned description, is a signal modulation element when using the actual operating gap GapZ. This means that it may be desirable for the average dimension DSME of the SME to be at least 0.66 * W1, or 0.7 * W1, or higher in some such embodiments.

When the signal modulator SME is a conductive plate rather than a conductive loop as shown in FIG. 4, the distribution of "concentric" eddy currents responds to the generated changing magnetic field GCMF and is such conductive. It should be understood that it can be produced on the plate. These eddy currents are operational comparable to the induced current Iind shown in FIG. If the conductive plates have the same average dimension DSME as the conductive loop SME shown in FIG. 4, their "equivalent current positions" are at the edges of the conductive plate due to the distributed "concentric" pattern of their eddy currents. Somewhere inside, the result is an effective width eff that is even smaller than that associated with a conductive loop of similar size. As a result, when a relatively large operating gap is used between the detection unit 367 and the scale pattern 380, the value of the average dimension DSME is relatively large, and in addition, the conductive plate type signal modulation element SME is described above. It may be particularly desirable to have an average dimension DSPE towards the larger end of the desired range outlined in. For example, the inventor has found that an average dimension DSME between 0.7 * W1 and 0.8 * W1 is advantageous in some such embodiments.

As a further consideration, with respect to the desired signal profile vs. displacement, the unwanted spatial harmonics contained in the signal profile are generally the shape of the signal modulation element SME and its effective width Gap, and the shape and width of the detection element SEN. And it should be understood that it depends on the operating gap between them. For example, in the above-described detection unit and scale configuration, when the effective width Weff is about 0.5 * W1, even-order spatial harmonics are mostly removed from the detection signal. However, odd-order spatial harmonics corresponding to 0.33 * W1 and the like may remain. In US Patent Application No. 16 / 021,528 published as US2020 / 0003581, 0.33 * W1 is supported by configuring the signal modulation element SME so as to provide an effective width Weff of 0.66 * W1. It is suggested that there is a tendency to suppress odd-order spatial harmonics. In addition, the present inventor has recently in patent No. 708 that the signal modulation element has an actual width of 5/6 * W1 regardless of whether or not there is a 1/6 * W1 width slot in the center thereof. It was found that it is suggested that the configuration so as to be (about 0.83 * W1) tends to suppress the odd-order spatial harmonics corresponding to 0.33 * W1. Note that this may not work as described in patent '708 because it does not take into account the description of effective width Weff above. In any case, these configurations did not actually achieve the expected or desired level of spatial filtering. Due to the high precision already achieved with the state-of-the-art electromagnetic induction encoders known to date, these configurations do not provide the expected or expected level of spatial filtering, which is the best in this regard. Advanced technology could not be improved or advanced as desired.

As disclosed herein, the inventor identifies a detection element SEN that can be used in combination with the configuration of the signal modulation element SME described above to ameliorate the drawbacks of spatial filtering described above. I found the composition. Various desirable configurations of the shape of the sensing element SEN are described in more detail below with reference to FIGS. 6, 7, and 8. Also, various desirable configurations according to predetermined relationships for the position and / or shape of the detection element SEN will be described in detail below with reference to FIGS. 9-13 and 14-17. However, prior to that, the definitions or interpretations of the specific dimensions and terms used in the description will be clarified with reference to the examples shown in FIGS. 5A and 5B. 5A and 5B are signals similar to those shown in FIG. 3, including additional examples of specific exemplary dimensions that can characterize their features according to the principles disclosed herein. FIG. 5 is a plan view schematically showing a specific aspect of an embodiment of a modulation element and a detection element.

5A and 5B illustrate embodiments of the respective electromagnetic induction encoders, showing further examples of the dimensions and terms DSENmax, DSENavg, DSME, EffRSME, EffASEN, and EffYSEN outlined earlier with reference to FIG. It is a plan view shown in. The dimensions YSEG are also introduced and explained. Some numbered components 5XX of FIGS. 5A and 5B may correspond to and / or provide similar behaviors or functions as the similar numbered components 3XX of FIG. It will be understood that, unless otherwise instructed, it can be understood as well.

5A and 5B show the spatial wavelength W1 and the aforementioned dimensions and terms applied to the non-linear boundary profile of the signal modulation element SME of FIG. 5A and the detection element of FIG. 5B. The effective region EffRSME of the signal modulation element SME shown above is within the region of the signal modulation element SME or the boundary indicated by the broken line in the area, is aligned with or overlaps with the internal region INTA, and is indicated by dot painting. Has been done. The DSME is an average dimension along the measurement axis direction MA of the "effective domain" EffRSME of the signal modulation element SME. In various embodiments, the average dimension DSME can be considered as the area of the effective region EffRSME of the signal modulation element SME divided by the y-axis dimension of the effective region EffRSME. For convenience and consistency of definition, in the case of the conductive plate type signal modulation element SME, the relevant dimensions may correspond to the edges of the SME, and in the case of the conductive loop type signal modulation element SME, the relevant dimensions. May correspond to the center line of the conductor. In the embodiment shown in FIGS. 5A and 5B, the dimension YSEP of the internal region INTA of the magnetic field generation coil FGC is smaller than the dimension in the −y axis direction of the signal modulation element SME and is included therein. The dimension of the region EffRSME in the y-axis direction is equal to the dimension YSEP. However, this does not have to be true in all embodiments (eg, as shown in FIG. 7), and the previous definition of effective region EffRSME is that the y-axis dimension of the effective region EffRSME is greater than the dimension of YSEP. It is more general, including small cases.

The effective region EffASEN of the detection element SEN outlined above is within the boundary indicated by the solid line within the region of the detection element SEN, is aligned with or overlaps the internal region INTA, and is indicated by diagonal marking. .. As outlined above, DSENmax is the maximum detection element width dimension along the x-axis direction or the measurement axis direction MA of the effective region EffASEN of the detection element SEN. DSENavg is the width dimension of the average detection element, and is defined as DSENavg = EffASEN / EffYSEN. As described above, EffYSEN is the dimension of the effective region EffASEN of the detection element in the y-axis direction. In the particular embodiment shown in FIGS. 5A and 5B, the effective y-axis dimension EffYSEN is equal to YSEP. This is because each of the detection elements SEN has a maximum detection element dimension along the y-axis direction that exceeds YSEP, and therefore its effective region EffASEN covers the entire dimension YSEP. In the particular embodiment shown in FIG. 5A, DSENavg is equal to DSNmax because the effective region EffASEN has parallel sides perpendicular to the x-axis and has a dimension YSEG that spans YSEP. For convenience, YSEG is defined as the y-direction dimension of a segment of a conductor that defines the detection element SEN, which is arranged apart from each other at the maximum dimension DSENmax and extends linearly along the y-axis direction. In the particular embodiment shown in FIG. 5B, the effective region EffASEN has a dimension DSENmax in the center along the y-axis direction, with its sides towards the top and bottom of the effective region EffASEN. Tapered or curved to narrow. Therefore, as shown, DSENavg is slightly smaller than DSENmax. For convenience and consistency of definition, when determining DSENavg = EffASEN / EffYSEN of the detection element SEN, the relevant dimensions may correspond to the center line of the conductor being defined. In the embodiments shown in FIGS. 5A and 5B, DSENmax is nominally 0.5 * W1. However, this value is not limited (for example, as shown in FIG. 8 below). The dimensions of the configuration of the detection element SEN shown in FIGS. 5A and 5B, DSENavg, are not preferred according to the principles outlined below with reference to FIGS. 6, 7, and 8, and the definition or quantification of DSENavg. It is presented only to clarify. The dimension CCSEN shown in FIG. 5B is the distance between the centers of the detection elements SEN along the x-axis direction. In various embodiments, it may be advantageous for CCSEN to be 0.5 * W1 regardless of the shape or size of the detection element SEN, DSENavg.

5A and 5B also show dimensions DSPC equal to W1 minus DSPE. Explaining the first method, the dimension DSPC can be described as corresponding to the "non-signal modulation space" between the first type of signal modulation element SMEs. However, to more generally describe a second method applied to various other embodiments of the periodic scale pattern, the dimensional DSPC can be described as corresponding to a second type of signal modulation element. The second type of signal modulation element can be arranged between the first type of signal modulation element SME along the measurement axis direction. The second type of signal modulation element is configured to have a relatively small effect on changes in magnetic flux as compared with the first type of signal modulation element SME. For example, in some embodiments, the second type of signal modulation device comprises a region of non-conductive material. In some such embodiments, the second type of signal modulation element comprises a region of a non-conductive scale substrate, and the first type of signal modulation element SME is manufactured and manufactured on the non-conductive scale substrate. / Or includes fixed conductors. As another example, in some embodiments, the second type of signal modulation device can include a "deeper recessed" region of conductive material used to form a scale pattern. One type of signal modulation device SME can include a "non-recessed" region of conductive material.

Here, returning to the discussion of filtering the error component (period of 0.33 * W1) of the third-order spatial harmonic from the signal of the detection element, as described above, the present inventor of the above-mentioned spatial filtering In order to improve the drawbacks, we have discovered a specific configuration of the detection element SEN that can be used in combination with the configuration of the signal modulation element SME described above. In the conventional technique, it is known that the error component of the third-order spatial harmonic is filtered from the signal of the detection element by various means. One approach is to theoretically configure the detection element in a sinusoidal shape that includes only the basic spatial frequency corresponding to W1. However, the error component of the third-order spatial harmonic cannot be completely suppressed due to various practical considerations, manufacturing restrictions, variations in assembly and gaps, and the like. Another approach is to arrange the detection element set SETSEN in the spatial phase separated by 0.33 * W1 and process the obtained signal to remove the error component of the third-order spatial harmonics. Although this method is relatively effective, many applications provide an orthogonal signal (ie, a spatially phased signal 0.25 * W1 away) from the detector set SETSEN for practical reasons. Is desirable, and therefore it is difficult or impractical to place a set of detectors SETSEN in spatial phases 0.33 * W1 apart (eg, due to layout constraints or interference). Maybe.

In order to solve the problems and defects inherent in the approach outlined above, we have described the configuration of the detector SEN to provide a particularly advantageous range of detector average dimensions DSENavg, the signal modulator SME outlined above. It has been found that the error components of the third-order spatial harmonics can be substantially filtered and / or suppressed when used in combination with the above configuration. Surprisingly, some encoder detectors and / or detector configurations do not include 0.33 * W1 in a particularly advantageous range, which is clearly expected based on theoretical considerations. Is to be done. For example, as disclosed herein, a detection element average dimension DSENavg of at least 0.285 * W1 and up to 0.315 * W1 is provided for wavelengths W1 and operating gaps in the practical range. When the detection element SEN configured as described above is used in combination with a signal modulation element SME having an average dimension DSPE of at least 0.55 * W1 and a maximum of 0.8 * W1, some detections. It is particularly advantageous for the configuration of the unit and / or the detection element. Various desirable configurations of such detection element SEN are described in more detail below with reference to FIGS. 6, 7, and 8.

6, 7, and 8 are plan views showing various embodiments of the scale pattern 680 including the detection element SEN and the signal modulation element SME. The disclosed embodiments are compatible with or can be used independently of the configuration principles of the detection elements disclosed herein with reference to FIGS. 9-12. In any case, the disclosed embodiments are suitable for use in the detector 667 (and / or 767, or 867) and scale pattern 680 in an electromagnetic induction encoder as shown in FIG. Also, FIGS. 6, 7, and 8 include examples of various dimensions that may characterize important features of the detector SEN. To make it easier to understand the conductor layout of the detector SEN, in the figure below, an arrow indicating the flow of current in the conductor segment and / or the "+" and / or "-" symbol inside the loop, The suffix (+) or (-) on the and / or label indicates the polarity of the loop. Some numbered and / or named components in FIGS. 6, 7, and 8 correspond to and / or similar components with similar numbers or names in FIGS. 5A and 5B. It will be understood that the operation can be provided and can be understood as well unless otherwise instructed. Therefore, in the following description, only specific differences between the detection element SEN and the signal modulation element SME will be emphasized.

The embodiment shown in FIG. 6 includes a signal modulation element SME similar to that shown in FIGS. 5A and 5B and has an effective region EffRSME having an average dimension DSPE of about 0.75 * W1 (in this particular embodiment). have.

The detection element SEN includes a conductor on the first machined layer (shown by a solid line) and a conductor on the second machined layer (shown by a dashed line), which are described in known methods (eg, cited literature). It is connected via the feedthrough FT according to the above method). In this embodiment, the magnetic field generation coil FGC is formed in a third processed layer in order to insulate the feedthrough FT. As shown in FIG. 6, the conductor of the detection element SEN has a short y-axis dimension YSEG, and is separated by DSENmax = 0.5 * W1 along the x-axis direction from the y-axis direction segment and the y-axis direction segment. Includes a segment that tapers from the directional segment towards the feedthrough FT. The relevant trapezoidal effective domain EffASEN (indicated by the shaded area in FIG. 6) has the y-axis dimension EffYSEN, which in this embodiment is equal to YSEP. Surprisingly, DSENavg = EffASEN / EffYSEN is at least 0.285 * W1 and at most 0.315 * in the shape of the detection element similar to this and in various embodiments using the signal modulation element SME. It was determined that it is advantageous when the detection element SEN is configured to be W1. In some embodiments, DSENavg may be particularly desirable if it is at least 0.29 * W1 and at most 0.31 * W1. Various values of DSENavg can be provided by appropriately setting the dimensions of the YSEG, as well as the positions of the feedthroughs and adjacent conductors, for a particular selection of DSENmax. In some such embodiments, the y-axis dimension YSEG may be at least 0.15 * W1. In the particular embodiment shown, the DSNmax is nominally 0.5 * W1, but if necessary, the detection element SEN near and adjacent to the dimension YSEG so that the DSNmax is less than 0.5 * W1. It is possible to construct the conductors of various layers so as to include overlapping x-axis segments between and.

FIG. 7 corresponds to similar numbered or named components of FIG. 6 (and FIGS. 5A and 5B) and / or has several numbered and / or named components that may operate similarly. It includes components, which can be similarly understood unless otherwise indicated. Therefore, in the following description, only specific differences between the detection element SEN and the signal modulation element SME will be emphasized. The embodiment shown in FIG. 7 includes a signal modulation element SME similar to that shown in FIG. 6 and has an effective region EffRSME with an average dimension DSME of about 0.75 * W1 (in this particular embodiment). ing.

The detection element SEN is similar to that shown in FIG. 6 and includes a conductor on the first machined layer (shown by a solid line) and a conductor on the second machined layer (shown by a dashed line). Connected via feedthrough FT according to known methods (eg, methods described in cited literature). However, the feedthrough FT is located within the internal region INTA. Thereby, in the present embodiment, the magnetic field generation coil FGC can be manufactured on the first and / or the third processed layer, and there is an advantage that the manufacturing cost of the detection unit 767 can be reduced. Compared with the embodiment shown in FIG. 6, the effective region EffASEN of the detection element SEN becomes smaller, and there is a drawback that the signal strength may decrease. However, for some applications this can be a desirable trade-off. The effective domain EffASEN (indicated by the shaded area in FIG. 7) has a y-axis dimension EffYSEN, which is smaller than YSEP in this embodiment. Surprisingly, DSENavg = EffASEN / EffYSEN is at least 0.285 * W1 and at most 0.315 * in the shape of the detection element similar to this and in various embodiments using the signal modulation element SME. It was determined that it is advantageous when the detection element SEN is configured to be W1. In some embodiments, DSENavg may be particularly desirable if it is at least 0.29 * W1 and at most 0.31 * W1. Various values of DSENavg can be provided by appropriately setting the dimensions of the YSEG, as well as the positions of the feedthroughs and adjacent conductors, for a particular selection of DSENmax. In the particular embodiment shown, the DSNmax is nominally 0.5 * W1, but if necessary, the detection element SEN near and adjacent to the dimension YSEG so that the DSNmax is less than 0.5 * W1. It is possible to construct the conductors of various layers so as to include overlapping x-axis segments between and. In the embodiment of the same shape, when DRENmax is 0.5 * W1 or less, it may be necessary to make the dimension of YSEG at least 0.14 * EffYSEN or more so that DSENavg is 0.285 * W1 or more. be.

FIG. 8 corresponds to similar numbered or named components of FIG. 6 (and FIGS. 5A and 5B) and / or has several numbered and / or named components that may operate similarly. It includes components, which can be similarly understood unless otherwise indicated. Therefore, in the following description, only specific differences between the detection element SEN and the signal modulation element SME will be emphasized. The embodiment shown in FIG. 8 includes a signal modulation element SME similar to that shown in FIG. 6 and has an effective region EffRSME with an average dimension DSME of about 0.75 * W1 (in this particular embodiment). ing.

The detection element SEN is similar to that shown in FIG. 6 and includes a conductor on the first machined layer (shown by a solid line) and a conductor on the second machined layer (shown by a dashed line). Connected via feedthrough FT according to known methods (eg, methods described in cited literature). In this embodiment, the magnetic field generation coil FGC is formed in a third processed layer in order to insulate the feedthrough FT. As shown in FIG. 8, the conductor of the detection element SEN has a long y-axis dimension YSEG (longer than and across the inner region INTA dimension YSEP) and is separated by DSENmax along the x-axis direction. Includes y-axis segments and segments that combine these segments into a feedthrough FT. The relevant rectangular effective domain EffASEN (shown in shaded area in FIG. 8) has a y-axis dimension EffYSEN, which in this embodiment is equal to YSEP. In this embodiment, DSENavg = DSENmax. In various embodiments using similar detection element shapes and signal modulation element SMEs, surprisingly, DSENmax and DSENavg are at least 0.285 * W1 and at most 0.315 * W1. It was determined that it is advantageous when the detection element SEN is configured as such. In some embodiments, DSENmax and DSENavg may be particularly desirable if they are at least 0.29 * W1 and at most 0.31 * W1. In the embodiment shown in FIG. 8, the sensitivity to unwanted signal changes that may occur due to various misalignment errors may be reduced.

For the advantageous range of dimensions DSME of the above signal modulation element SME, in many practical applications using the maximum practical gap allowed in consideration of signal strength, the most advantageous value of DSME is It may be at least 0.66 * W1, or 0.7 * W1, or more. For example, in various embodiments, it has been confirmed that it is particularly advantageous to set the value of DSME to 0.75 * W1. However, as suggested in previous discussions, this may depend to some extent on a particular wavelength W1, a particular operating gap and operating frequency, and a particular shape and structure of the signal modulation element SME.

For the advantageous range of the dimensions DSENavg of the above-mentioned detector element SEN, the maximum practical gap allowed in consideration of signal strength and the most advantageous value of DSME outlined above (eg DSME = 0.75). In many practical applications using * W1), at least for the shape of the sensing element similar to that outlined above with reference to FIGS. 6-9 and for embodiments using the signal modulation element SME. The value of DSENavg, which is an advantageous combination, is preferably in the range of 0.29 * W1 to 0.31 * W1. In such an embodiment, DSENavg = 0.30 * W1 has been confirmed to be particularly advantageous. However, as suggested in previous discussions, this depends to some extent on a particular wavelength W1, a particular operating gap, a particular dimensional DSME, and a particular shape and structure of the signal modulation element SME.

It should be understood that the error component of the third-order spatial harmonics in the signal from the signal modulation element set SETSEN is extremely sensitive to dimensional selection within the ranges disclosed above. For example, the dimension DSENavg may reject the error component of the third-order spatial harmonics of the signal with respect to the practical variation of the manufactured dimensions and the variation of the operating gap associated with the signal modulation element set SETSEN. It is desirable to be selected. Surprisingly, when using a sensing element shape and signal modulation element SME similar to those described above, in one embodiment configured to provide a value of 0.3 * W1 for DSENavg. The error component related to the error component of the third-order spatial harmonic is uniformly insensitive to fluctuations in the dimensional DSME of the signal modulation element SEN over the range of DSPE = 0.72 * W1 to DSPE = 0.79 * W1. The present inventor has found that. On the other hand, when DSENavg is changed from this value by about 10% (for example, to 0.27 * W1 or 0.33 * W1), the detection element in the range of DSME = 0.72 * W1 to DSME = 0.79 * W1. The error component of the third-order spatial harmonic increases more than 10 times with respect to the fluctuation of SEN, which is unacceptable.

The reason why the advantageous range of the disclosed dimensions DSENavg is so different from the "simply" expected value of 0.33 * is that the error component due to the impedance fluctuation of the detector depending on the position of the scale is DSENavg. There may be an explanation that it is affected. Such position-dependent impedance fluctuations can be on the order of 1% and are not known or considered in the prior art. The advantageous range of DSENavg disclosed herein is to "tune" or "tune" these impedance fluctuations, and the contribution of their signal components to be "aliased" in addition to the error components of the third-order spatial harmonics. It is possible that the sum of the effects cancels out the error component of the third-order spatial harmonics when combined with the source of. Such subtle effects and related design characteristics have not been considered in the prior art. For embodiments of detectors and signal modulation devices similar to those outlined above with reference to FIGS. 6-8, particularly advantageous values for DSENavg have been verified and identified above, but such values are Please understand that it is exemplary and not limiting. For example, in the embodiment of other detection units and signal modulation elements, the advantageous range of the value of DSENavg may be different. It is considered that this is because, as described above, the error components generated from the scale position-dependent impedance fluctuation of the detection unit are different. Therefore, the specific detector configured according to the predetermined relational principle of the first type or the second type disclosed below with reference to FIGS. 9 to 17 is 0.285 * W1 to 0.315 * W1. It should be understood that it may be beneficial to use a particular DSENavg value that is outside the range of. For example, if the value of DSENavg is within a large range of 0.33 * W1 ± 15%, it is unnecessary in various detectors configured according to the predetermined relational principle of the first type or the second type shown below. It may be useful to sufficiently reduce or suppress the third-order spatial harmonic detection signal component. In particular, the value of DSENavg in the range of 0.33 * W1 ± 15% is configured to sufficiently reduce or suppress unnecessary third-order spatial harmonic detection signal components, which are further shown below. It is configured to reduce or suppress unwanted 5th (or 7th, or 9th) spatial harmonic detection signal components according to a predetermined relationship principle of the first type or the second type. In the case, an unprecedented level of spatial filtering is provided to suppress unwanted spatial harmonics. In addition, unprecedented levels of spatial filtering are achieved using a less complex, more powerful, and more economically manufacturable detector layout.

In FIGS. 9 to 13, the detection element SETSEN is compatible with the spatially filtered signal for use in the detection unit X67 (for example, 967, 1367, etc.) of the electromagnetic induction type encoder as shown in FIG. Configured or arranged according to the predetermined relational principle of the first type disclosed herein, which is arranged to provide with a magnetic field generation coil FGC and a scale pattern X80 (eg, 980, 1380, etc.). Sensing Element Set Set is a partially specific, partially schematic, plan view showing specific aspects of various exemplary configurations of the detector set SETTEN and used to dispose of those detector elements SETSEN. It contains various dimensions that can characterize a given type of relational principle of the first type. According to the promises used herein, embodiments that comply with certain first type of relational principles (discussed in more detail below) may be referred to as first type embodiments for short. be.

The principles outlined below with reference to FIGS. 9-13 are detection elements for spatially filtering potential 5th (or 7th, or 9th) harmonic components in the detection signal. It is advantageous to place the SEN, especially when used in combination with a detection element SEN formed to spatially filter potential third harmonic components in the detection signal according to the principles outlined above. Is. However, the principles for arranging the detection element SEN to spatially filter potential harmonic error components, outlined below with reference to FIGS. 9-13, are not so limited. It should be understood that there is no such thing. More generally, these principles can be used in combination with various other sensing element SENs and signal modulation element SMEs (eg, known in the prior art) and may still provide great advantages. ..

Conventionally, the detection element SEN has been periodically arranged along the measurement according to the wavelength W1 as described above. In particular, the positive loops of the detection element SEN are typically uniformly arranged with a center spacing W1 or a multiple of W1, and the negative loops of the detection element SEN are typically center spacing W1 or a multiple of W1. It is uniformly arranged in multiples of W1. Further, the positions of the positive electrode loop and the negative electrode loop are generally offset uniformly from each other by (W1) / 2 along the measurement axis direction. Such positions and intervals are considered to be optimal for spatially filtering the signal strength and potential spatial harmonics (second, fourth, etc.) contained in the detected signal. However, the inventor has the following in order to obtain the highest accuracy in a variety of applications in order to provide spatial filtering to mitigate certain additional error components that may otherwise appear. As described in detail, it has been found that it may be desirable for the sensing element SEN to use different positions and / or spacings.

FIG. 9 is a predetermined of the first type disclosed herein to provide a spatially filtered signal for use in the detector of an electromagnetic induction encoder as shown in FIG. A specific aspect of the first detection element set SETSEN-Ph0 (also abbreviated as SETSEN) corresponding to the first spatial phase Ph0, which is the first exemplary configuration of the detection element set configured according to the relational principle of. Is shown, along with a first compatible magnetic field generation coil FGC and scale pattern 980, including various dimensions that characterize the detection element configuration according to the principles disclosed herein. FIG. 9 corresponds to similar numbered or named components of FIGS. 2, 3, and 8 and / or some numbered and / or named components that may operate similarly. Including, these can be understood as well unless otherwise indicated. Therefore, in the following description, only specific differences in the position of the detection element SEN of the detection unit 967 will be emphasized.

Briefly, the detection element SEN is similar to that shown in FIG. 8 in terms of its general shape, its effective region EffASEN, and its dimensions DSENavg. In the particular embodiment shown in FIG. 9, DSENavg is about 0.3 * W1, but as described above, this is exemplary and limited in various embodiments of the first type. It's not something like that. The detection element SEN includes a conductor on the first machined layer (shown by a solid line) and a conductor on the second machined layer (shown by a dashed line), which are described in known methods (eg, cited literature). It is connected via a feedthrough FT (eg, an inner layer feedthrough that is insulated from the magnetic field generation coil FGC) according to the above method. In some places in FIG. 9, the "non-loop" portions of the conductors of different layers are aligned with each other, showing only a single conductor layer. The presence of hidden "aligned" conductors can be inferred by those skilled in the art. In this embodiment, the magnetic field generation coil FGC is made in a third processed layer in order to insulate the feedthrough FT and the conductor connected thereto. To make it easier to understand the conductor layout of the detector SEN, in the figure below, an arrow indicating the flow of current in the conductor segment and / or the "+" and / or "-" symbol inside the loop, The suffix (+) or (-) on the and / or label indicates the polarity of the loop.

As implicitly shown in FIG. 9, the scale extends along the measurement axis direction (MA) and includes a periodic scale pattern 980 with a signal modulation element SME and a spatial wavelength W1. The detector 967 is configured to be mounted in close proximity to the periodic scale pattern 980 so as to move relative to each other along the measurement axial direction MA. The detection unit 967 includes a magnetic field generation coil FGC and at least one respective detection element set SETSEN corresponding to each nominal spatial phase. In the particular embodiment shown in FIG. 9, each sensing element Tosset SETSEN comprises two subsets or partials of SETSEN-Ph0sub1 and SETSEN-Ph0sub2, each with a nominal spatial phase Ph0, as described in more detail below. It corresponds. The magnetic field generation coil surrounds an internal region INTA aligned with the effective region EffRSEN of the operating signal modulation element SME. Each detection element set SETSEN is arranged along the measurement axis direction and fixed to the substrate. Members of the detection element set consist of a conductive loop or conductive loop portion that defines the detection element effective region EffASEN corresponding to the portion of the detection element that is aligned with or overlaps the internal region INTA. The detection element set SETSEN is configured to provide a detection signal according to the local influence on the magnetic flux change provided by the adjacent signal modulation element SME of the scale pattern 980, and corresponds to its nominal spatial phase Ph0. ing. The signal processing unit may be operably connected to the detection unit to provide a coil drive signal, as outlined earlier herein, with the detection unit based on the detection signal input from the detection unit. Determine the position relative to the scale pattern.

In various embodiments of the first type configured to provide spatially filtered detection signals, as disclosed below with reference to FIGS. 9-13, for each nominal spatial phase. Each of the corresponding at least first detection element sets SETSEN comprises features A1, B1 and C1 to be combined, and further combines at least one of features D1 or E1 as defined below.

A1) A plurality of positive loops corresponding to the first winding direction or polarity and the same number of negative loops corresponding to the second winding direction or polarity opposite to the first winding are provided.

B1) Each of the positive loop and the negative loop has all detection element effective regions EffASEN that are aligned with the internal region or overlap with one or more internal regions, and one or more perpendicular to the measurement axis direction. Defined to have an effective y-axis dimension EffYSEN along the y-axis direction, which is the sum of the dimensions of the internal regions of the DSENavg = (EffASEN / EffYSEN) is configured to be within the range of 0.33 * W1 ± 15%.

C1) The positive electrode loop is configured such that the effective region of the detection element is arranged in the positive loop regulation relationship (abbreviated as the positive loop regulation relationship) with respect to each nominal spatial phase of each detection element set, and the negative electrode. The sex loop is configured such that the detection element effective region is arranged in a negative loop regulation relationship (abbreviated as a negative loop regulation relationship) with respect to each nominal spatial phase of each detection element set. In the positive loop regulation relationship, the shift ratio up to half of the effective region of all detection elements of a plurality of positive electrode loops is (W1) / 4K in relation to each nominal spatial phase along the measurement axis direction in the first direction. Shifted, the nominally same shift ratio of all detection element effective regions of multiple positive loops is along the measurement axis direction in the direction opposite to the first direction by (W1) / 4K in relation to each nominal spatial phase. The two shift ratios of the effective regions of all the detection elements in the positive loop region are shifted relative to each other by (W1) / 2K, and K is among 3, 5, 7, and 9. It is characterized by being one of. In the negative loop regulation relationship, the shift ratio up to half of the effective region of all the detection elements of the plurality of negative electrode loops is (W1) / 4K in relation to each nominal spatial phase along the measurement axis direction in the first direction. Shifted, the nominally same shift ratio of all detection element effective regions of multiple negative electrode loops is along the measurement axis direction in the direction opposite to the first direction by (W1) / 4K in relation to each nominal spatial phase. The two shift ratios of the effective regions of all the detection elements in the negative electrode loop region are shifted relative to each other by (W1) / 2K.

D1) Each of the positive and negative loops is composed of a detection element effective region EffASEN in which the maximum dimension DSENmax in the measurement axis direction is 0.45 * W1 at the maximum.

E1) Each detection element set corresponding to each nominal spatial phase (SETSENPh0) has a first separation portion composed of the same number of positive electrode loops and negative electrode loops, and the first separation portion and the measurement axis direction. It is composed of two parts, a second separation part that is nominally aligned along the line and has the same number of positive and negative loops as the first separation part, and is composed of a first separation part and a second separation part. The separation part is separated by a gap located along the measurement axis direction between the first separation part and the second separation part, and the gap is a positive loop or a negative electrode along the measurement axis direction. It has at least the same width as one of the loops, and the effective region of the positive loop or the effective region of the negative loop of each detection element set is not located in the gap.

As a result of implementing the combination of the above features A1, B1, and C1 and at least one of the features D1 or E1, the detection element set SETSEN corresponding to each nominal spatial phase is thereby subjected to the detection unit and the scale pattern. Reduces or suppresses both potentially unwanted third-order spatial harmonic detection signal components and K-th-order spatial harmonic detection signal components that can cause errors in the determined relative positions between. It has a practical configuration that provides a spatially filtered detection signal or multiple detection signals that can be used to do so. Some embodiments of the first type may be particularly advantageous when K = 5, as described in more detail below with respect to the various figures. In certain embodiments of the first type, at least half or more of the positive and negative loop SENs provide a detection element average dimension DSENavg of at least 0.29 * W1 and up to 0.31 * W1. Although it may be advantageous to be configured, this scope is exemplary only and not limiting for specific embodiments.

9-13 (and further below FIGS. 14-17) are several instances of each spatial phase Ph0 (also referred to and / or indicated) separated by wavelength W1. It includes a "reference grid" that indicates the position of, and more clearly shows how each sensing element set SETSEN is configured according to the principles described above. Further, the center position of the effective region EffASEN of each detection element SEN is indicated by the position of the center line CLSEN of the broken line for the same purpose.

Returning to the further discussion of the embodiment shown in FIG. 9, based on the reference grid and centerline indicators shown in FIG. 9, the detection element set SETSEN shown in FIG. 9 has features A1, B1, C1 and D1 outlined above. Will be understood by the scrutiny of FIG. A brief explanation is as follows.

In the embodiment shown in FIG. 9, each sensing element set SETSEN comprises two similar subsets or partial SETSEN-Ph0sub1 and SETSEN-Ph0sub2 corresponding to their respective nominal spatial phases Ph0. Each sensing element set SETSEN has a plurality of positive loops (indicated by "+" inside the loop) corresponding to the first winding direction or polarity and a second winding opposite to the first winding. Includes the same number of negative loops (indicated by "-" inside the loop) corresponding to the line direction or polarity. In the particular embodiment shown in FIG. 9, the two subset or partial SETSEN-Ph0sub1 and SETSEN-Ph0sub2 individually contain the same number of positive and negative loops.

Of all the detection element effective regions of the positive loop of the detection element SETSEN, the first half located in the positive loops SEN2 and SEN4 (that is, the first half of the total of the detection element effective regions EffASEN) is nominal. In relation to the spatial phase Ph0, it is shifted in the first direction along the measurement axial direction MA by (W1) / 4K, and is located in the positive loops SEN5 and SEN7 in the effective region EffASEN of all the detection elements of the positive loop. The second half is shifted in the direction opposite to the first direction along the measurement axis direction MA by (W1) / 4K in relation to the nominal spatial phase Ph0nom. As a result, the first and second halves of the entire detection element effective region of the positive loop region are relatively shifted to each other (W1) / 2K along the measurement axis direction.

Of all the detection element effective regions EffASEN of the negative electrode loop of the detection element SETSEN, the first half located in the negative loops SEN1 and SEN3 is related to the offset of (W1) / 2 from the nominal spatial phase Ph0nom. (W1) / 4K is shifted in the first direction along the measurement axial direction MA, and the second half of the effective region EffASEN of the entire detection element of the negative electrode loop, which is located in the negative loops SEN6 and SEN8, is nominal. In relation to the offset of (W1) / 2 from the spatial phase Ph0nom, only (W1) / 4K is shifted along the measurement axis direction MA in the direction opposite to the first direction. As a result, the first and second halves of the entire detection element effective region of the negative electrode loop region are relatively shifted to each other (W1) / 2K along the measurement axis direction. In the particular embodiment shown in FIG. 9, the illustrated shift corresponds to K = 5, which is exemplary and not limiting as already shown in the description of feature C1.

In the particular embodiment shown in FIG. 9, the average detection element dimension DSENavg (= EffASEN / EffYSEN) is illustrated to be within the range of 0.33 * W1 ± 15%, which relates to principle or feature B1. It conforms to the explanation so far.

As a result of implementing the features A1, B1, and C1 as described above, each detection element set SETSEN corresponding to each nominal spatial phase Ph0 shown in FIG. 9 is thereby between the detector and the scale pattern. Potentially unwanted third-order spatial harmonic signal components that may contribute to the determined relative position error are reduced or suppressed (based on B1 above) and are also potentially unwanted. It is configured to provide a spatially filtered detection signal or plurality of detection signals that can be used to reduce or suppress the Kth order spatial harmonic signal component (based on C1 above).

Regarding the embodiment of the feature D1, in the implementation shown in FIG. 9, the detection element maximum dimension DRENmax is the same as the detection element average dimension DSENavg, and is about 0.33 * W1. This is smaller than the requirement of feature D1 of 0.45 * W1. One aspect of the usefulness of the feature D1 in the embodiment shown in FIG. 9 is shown by the layout of the detection elements SEN4 and SEN5, which are shifted from each other by the total amount (W1 / 10) in the illustrated embodiment. If the maximum dimensions DSENmax of the detectors SEN4 and SEN5 are wide, the layout of their conductors will overlap and / or interfere between them, facilitating the placement of feedthroughs, and / or insulating between the various conductors. It will be appreciated that layout adjustments and / or irregularities or distortions of the sensing elements (eg, as depicted in the '130 patent) are required to provide. Patent No. '130 aims to provide an aligned center of gravity for the purpose of eliminating errors due to "pitch" deviations (rotation of the detector or scale about the Z axis). The solution implements the teaching using a detector element with a nominal maximum dimension of W / 2, resulting in a number of problematic layout adjustments and irregularities in the detection area (eg, shown in FIG. 8). Like). However, such layout and irregularities in the detection area can adversely affect manufacturing cost, accuracy, sensitivity to misalignment, and the like, even with the utmost care. In contrast, by implementing feature D1 with the configuration shown in FIG. 9, any of the detection elements SEN of the detection element set SETSEN overlaps or interferes with the detection element effective region of the other detection element SEN. Despite having no effective region EffASEN and shifting the detection element SEN according to the principles disclosed herein, layout irregularities, detection element irregularities, and the harmful effects associated therewith are present. Avoided.

In the specific embodiment shown in FIG. 9, the detection element set SETSEN is composed of two parts, and the detection element set SETSEN has the same number as a plurality (two) positive electrode loops (SEN1 and SEN3). A first adjacent portion SETSEN-Ph0sub1 with (2) negative electrode loops (SEN2 and SEN4), and the same number (2) negative loops as a plurality (2) positive loops (SEN5 and SEN7). A second adjacent portion SETSEN-Ph0sub2 comprising (SEN6 and SEN8) is provided. The first and second flanking sections are located closer to each other along the measurement axis than the width of one of the positive or negative loops (hence the term "adjacent" section herein. ), The respective loops of the first and second adjacent portions closest to each other (ie, SEN4 and SEN5) have opposite loop polarities. However, such embodiments are exemplary and not limiting. An alternative example of the two-part configuration will be described in detail below. The region center of gravity CEN-SEETSEN-Ph0 of the detection element set SETSEN will be described later with reference to FIGS. 10 and 11.

For signal processing relating to a configuration consisting of various two parts, in various embodiments including the first and second parts (eg, two adjacent parts, or two separate parts, as further outlined), electromagnetic. The inductive encoder may be configured according to either method M1 or M2 described below.

Method M1) The first part is configured to output the first detection signal (eg, the voltage signal V0 between the detection signal output connection SDS1 and SDS2), and the second part is the second detection signal (eg, the second detection signal). , Detection signal output connection is configured to output a voltage signal V0') between SDS1'and SDS2', and the signal processing unit and the detection unit are at least partially based on the combination of the first and second signals. It is configured to determine the relative position with respect to the scale pattern.

Method M2) The first part is connected in series with the second part to form a composite signal, and the series connection is configured such that the signal contributions of the first and second parts are added to each other in the composite signal. The signal processor is configured to determine the relative position between the detector and the scale pattern, at least partially based on the composite signal.

One exemplary embodiment of series connection by M2 can be described with reference to the aligned trace zone ATZ shown in FIG. In particular, the feedthrough illustrated in the aligned trace zone ATZ is eliminated and "solid" traces of the detector elements SEN4 and SEN5 in contact with the aligned trace zone ATZ are placed on the metal layer in which they are arranged together. May be connected by a trace across. Similarly, "dashed" traces of the detector elements SEN4 and SEN5 that come into contact with the aligned trace zone ATZ may be connected by traces across the aligned trace zone ATZ on the metal layer in which they are located. If the two connection traces on the two layers are aligned with each other, no loop region will occur and no significant signal disturbance will occur. When such a series connection is used, of a pair of detection signal output connections SDS1 and SDS2, or SDS1'and SDS2'(eg, shown in FIGS. 9 and / or other figures herein). One of may be omitted and the associated connection points on the associated detector loop are reconstructed for conductor conduction in a manner similar to the other "connectionless" detector loops shown. May be done. This type of series connection is shown in FIG. 16 showing a series connection between its adjacent portions SETSEN-Ph90sub1 and SETSEN-Ph90sub2 (ie, between the respective detection elements SEN4 and SEN5). When the adjacent portions are connected in series, in some embodiments, the resulting set of detectors SETSEN may be visually represented as a continuous, uninterrupted set of detectors (eg, FIG. 16). As shown). In such cases, such a detector set SETSEN may be interpreted as a single contiguous set in some contexts, or, in some contexts, a contiguous, uninterrupted detection. It should be understood that it may be interpreted as the first and second adjacencies connected to create the appearance of the device set. In some embodiments, a series connection may be provided between the appropriate one of the detection signal output connections SDS1 or SDS2 and the appropriate one of the detection signal output connections SDS1'or SDS2'. .. Other alternative configurations of series connection will be apparent to those skilled in the art. The two-part signal processing and / or series connection options described above are generally applicable to any of the compatible two-part configurations shown in any of FIGS. 9-17. Will be understood. In each of the detection element sets shown in FIG. 10, when a series connection is provided to the aligned trace zone ATZ between SEN4 and SEN5, they are each a visually continuous and uninterrupted detection element set, as described above. It will be appreciated that it may be expressed and / or considered as. In such a case, it will be understood that each detection element set of FIG. 10 is considered to include features A1, B1, C1 and D1 and not feature E1.

FIG. 10 shows an aspect of a second sensing element set SETSEN-Ph90 (referred to as SETSEN for short in some contexts below) corresponding to a second spatial phase Ph90 (denoted as Ph90nom in FIG. 10). It is a top view which shows. It is configured to be similar or identical to the first detection element set SETSEN-Ph0 shown in FIG. 9 (except for its spatial phase) and is therefore not described in detail here. The reference numeral of the detection element SEN shown in FIG. 10 is arranged at the center of the detection element of the second detection element set SETSEN-Ph90. This is shown superimposed on the non-emphasized representation of the first detection element set corresponding to the first spatial phase Ph0 illustrated in FIG. 9, the first detection element set SETSEN-Ph0 and the second detection. The operation quadrature configuration in which the spatial topologies of the element set SETSEN-Ph90 differ by 90 degrees is shown. FIG. 10 corresponds to similar numbered or named components of FIG. 9 and / or includes several numbered and / or named components that may operate similarly or identically. Can be understood in the same way unless otherwise instructed. Therefore, in the following description, only a specific relationship between the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 will be emphasized.

As shown in FIG. 10, the second detection element set SETSEN-Ph90 is 90 degrees different from the spatial phase of the first detection element set SETSEN-Ph0 (that is, shifted 90 degrees to the right) and corresponds to the spatial phase. Has. The first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 are omitted in FIG. 10 and the other figures thereafter to avoid visual clutter, respectively, but are shown in FIG. It will be appreciated that the detection signal output connections SDS1 and SDS2, as well as SDS1'and SDS2', are similar to those shown. The first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 include advanced spatial filtering according to the above principle in order to operate together to perform highly accurate position measurement. Output an orthogonal signal. Both the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 have features A1, B, C1 and D1 and therefore the various advantages described above with reference to FIG. I will provide a. As seen in FIG. 10, the layout and performance advantages associated with the embodiments of these features are superimposed "quadrature layouts" of the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90. It will be understood that it extends to. That is, in the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90, their conductors do not interfere with each other, and the shape of the detection element SEN requires irregularity or difference. It will be appreciated that it is easily laid out in the desired phase relationship without the need for it. Therefore, the layout and performance advantages outlined above are provided in a fully operational quadrature encoder layout as shown in FIG.

The embodiment shown in FIG. 10 has some aspects that are not ideal for some applications. In particular, as shown in FIG. 10, the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 are substantially similar or the same, and the first detection element set SETSEN-Ph0 or the second detection element set is set. Since none of the detection element sets SETSEN-Ph90 of the above has the feature E1, the region center of gravity CEN-SETENS-Ph90 of the second detection element set SETSEN-Ph90 is the region center of gravity CEN-of the first detection element set SETSEN-Ph0. It is shifted by 90 degrees spatial phase shift (that is, W1 / 4) with respect to SETSEN-Ph0. If the region centroids of two different sets of sensing elements corresponding to two different spatial phases are misaligned, as taught in patent '130, their associated detectors (eg, detector 967) or The pitch shift of the scales (eg, scale pattern 980) results in differences in their respective operating gaps and signal strengths. Such pitch shifts may be static or dynamic in a variety of applications. In any case, the static or dynamic difference in signal strength between two orthogonal signals (or three three-phase signals) is more complex signal processing (eg, undesirably expensive and / or slow). It requires signal processing) or causes unwanted measurement errors. The embodiment shown in FIG. 11A addresses these potential concerns.

FIG. 11A is a specific set of second sensing element sets SETSEN-Ph90 (referred to as SETSEN for short in some contexts below) corresponding to a second spatial phase Ph90 (indicated as Ph90nom in FIG. 11A). It is a top view which shows the side surface. It is a second exemplary configuration of a set of sensing elements configured according to a given type of relational principle of the first type disclosed herein. It is shown in FIG. 11A together with the first detection element set SETSEN-Ph0 corresponding to the first spatial phase Ph0 illustrated in FIG. For illustration purposes, the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 are shown in FIG. 11A to better show the individual characteristics and their relative alignment along the measurement axis direction. Are vertically offset from each other. These are arranged in a quadrature configuration that can operate along the measurement axis direction, and the spatial phases of the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 are different by 90 degrees. In a real encoder, you can see that they are not offset from each other along the "y-axis" direction. Rather, they overlap each other, similar to the first and second sets of sensing elements shown in FIG.

FIG. 11A corresponds to similar numbered or named components of FIGS. 9 and / or 10 and / or some numbered and / or named configurations that may operate similarly or identically. It includes elements, which can be understood as well unless otherwise indicated. Therefore, in the following description of FIG. 11A, only specific differences in the configuration of the second detection element set SETSEN-Ph90 will be emphasized.

The difference between the embodiment of the second detection element set SETSEN-PH90 shown in FIG. 11A and the embodiment shown in FIG. 10 can be briefly explained as follows. The first detection element set SETSEN-Ph0 can be regarded as unchanged from the description of FIGS. 9 and 10. It can be considered that the detection elements SEN5 to SEN8 of the second part SETSEN-Ph90sub2 have not been changed from the description of FIG. The detection elements SEN1 to SEN4 of the first portion SETSEN-Ph90sub1 have been changed from the description of FIG. In particular, in the embodiment shown in FIG. 11A with respect to those positions in FIG. 10, their layout has moved to the left by (W1) / 2, and the output signal connection is currently connected to the rightmost detection element SEN4. It is provided and remains associated with the trace of the positive loop due to the conceptual continuity between FIGS. 10 and 11. According to the above description, there is no difference in the operation of the first portion SETSEN-Ph90sub1 in the relationship between the signal output and the position, as shown in FIGS. 10 and 11. Further, the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 shown in FIG. 11A have features A1, B, C1 and D1 and are therefore described above with reference to FIG. It offers various advantages.

Importantly, the embodiment shown in FIG. 11A has a more ideal aspect than the embodiment shown in FIG. 10 for applications that may include pitch shifts. In particular, as shown in FIG. 11A, since the first portion SETSEN-Ph90sub1 is shifted to the left by (W1) / 2 with respect to the position of FIG. 10, the entire second detection element set SETSEN-Ph90. The regional center of gravity CEN-SETSEN-Ph90 is shifted to the left by (W1) / 4 so as to be aligned with the regional center of gravity CEN-SETSEN-Ph0 of the first detection element set SETSEN-Ph0. Become. When the regional centroids of two different sets of sensing elements corresponding to two different spatial phases are aligned, their respective operating gaps and signal strengths are static, as taught in patent '130. Targeted or dynamic pitch shifts are similarly affected, which eliminates most of the errors that can occur due to pitch shifts.

Embodiments of the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 shown in FIG. 11A can be comprehensively described as follows without referring to FIG. The first detection element set SETSEN-Ph0 corresponds to the first spatial phase Ph0 and includes features A1, B1, C1, and D1 (not features E1). It is a first adjacent portion SETSEN-Ph0sub1 with a plurality of (2) positive loops (SEN1 and SEN3) and an equal number (2) of negative loops (SEN2 and SEN4), and a plurality (2). It is composed of two parts including a second adjacent portion SETSEN-Ph0sub2 having the same number (two) of negative loops (SEN6 and SEN8) as positive loops (SEN5 and SEN7). The first and second flanking sections are located closer to each other along the measurement axis than the width of one of the positive or negative loops (hence the term "adjacent" section herein. ), The respective loops of the first and second adjacent portions closest to each other (ie, SEN4 and SEN5) have opposite loop polarities. The second detection element set SETSEN-Ph90 corresponds to the second nominal spatial phase Ph90 and comprises features A1, B1, C1, D1, and E1. It is configured to include feature E1 as follows. It is a first separation part SETSEN-Ph90sub1 composed of the same number (two) of positive electrode loops (SEN2, SEN4) and negative electrode loops (SEN1, SEN3), a first separation part SETSEN-Ph90sub1 and a measurement shaft. A second that is nominally aligned along the direction and has the same number (two) of positive loops (SEN5, SEN7) and negative loops (SEN6, SEN8) as the first separator SETSEN-Ph90sub1. It is composed of two parts including a separation part SETSEN-Ph90sub2. The first separation part SETSEN-Ph90sub1 and the second separation part SETSEN-Ph90sub2 are separated by a gap located along the measurement axis direction between the first separation part and the second separation part. Is at least as wide as either the positive or negative loop along the measurement axis. The positive loop effective region EffASEN or the negative loop effective region EffASEN of the second detection element set SETSEN-Ph90 is not located in the gap.

The first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 can be further described as follows. The second detection element set SETSEN-Ph90 corresponds to a nominal spatial phase Ph90 that is 90 degrees different from the nominal spatial phase Ph0 of each of the first detection element sets SETSEN-Ph0. In the second detection element set SETSEN-Ph90, the loops of the first separation part SETSEN-Ph90sub1 and the second separation part SETSEN-Ph90sub2, which are closest to each other (for example, SEN4 and SEN5), are the same. It is configured to have loop polarity. The first detection element set has a first region center of gravity of its entire detection element effective region located along the measurement axis between its first and second adjacent portions. Each of the second detection element sets SETSEN-Ph90 is a second region of the entire detection element effective region located along the measurement axis between the first separation unit SETSEN-Ph90sub1 and the second separation unit SETSEN-Ph90sub2. It has a center of gravity CEN-SETSEN-Ph90. In the first and second detection element sets, the first region center of gravity CEN-SETSEN-Ph0 and the second region center of gravity CEN-SETSEN-Ph90 are arranged at the same position along the measurement axis direction.

As mentioned above, when the regional centroids of two different sets of sensing elements corresponding to two different spatial topologies are aligned, their respective operating gaps and signal intensities are static or dynamic pitch shifts. Is similarly affected by, which eliminates most of the errors that can be caused by pitch shifts. According to one useful point of view, since the second detection element set SETSEN-Ph90 includes the feature E1, the detection element set so that the regional centers of gravity of the plurality of detection element sets SETSEN are aligned in a usable configuration. It facilitates (or is a by-product of) rearranging and / or rearranging a particular loop or sensing element SEN in order to rearrange the region centroid of the SETSEN in the desired relationship with respect to its nominal spatial phase. It should be understood to include a gap (ie, the gap shown between SEN4 and SEN5).

Looking at FIG. 11A, in contrast to the region center of gravity alignment technique disclosed in Patent No. 130, the first detection element set SETSEN-Ph0 and the second detection element set SETSEN shown in FIG. 11A. -Ph90 is a state in which the center of gravity of their regions is easily aligned in a desired phase relationship without the conductors interfering with each other and without requiring irregularities or differences in the shape of the detection element SEN. It will be understood that it will be laid out. Therefore, by using the combination of features A1, B1, C1, D1 and E1 shown with reference to FIG. 11A, the layout and performance advantages described with reference to FIGS. 9 and 10 are fully operational. It is provided with an orthogonal encoder layout, and also offers the advantages associated with aligned region centroids.

In the embodiment shown in FIG. 11A, each positive or negative loop (eg, each detection element SEN) included in one of the first detection element set SETSEN-Ph0 or the second detection element set SETSEN-Ph90 is , Each detection element effective region EffASEN that does not overlap with the detection element effective region EffASEN of each other positive or negative loop contained in the same one of the first or second detection element set. Will be understood. The first type of embodiment outlined above with reference to FIGS. 9, 10, and 11A is more complex than prior art spatial filtering detectors (eg, those disclosed in patent '130). Instead, it is understood that a high-performance, economically manufacturable detector layout can be used to provide an unprecedented level of spatial filtering that suppresses multiple unwanted spatial harmonic signal components. Will be done.

FIG. 11B is a specific set of first sensing element sets SETSEN-Ph0 (referred to as SETSEN for short in some contexts below) corresponding to a first spatial phase Ph0 (indicated as Ph0nom in FIG. 11B). It is a top view which shows the side surface. It is a third exemplary configuration of a set of sensing elements configured according to a given type of relational principle of the first type disclosed herein. It is shown in FIG. 11B, along with a second detection element set SETSEN-Ph90 corresponding to the second spatial phase Ph90 illustrated in FIG. 11A. For illustration purposes, the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 are shown in FIG. 11B to better show the individual characteristics and their relative alignment along the measurement axis direction. Are vertically offset from each other. These are arranged in a quadrature configuration that can operate along the measurement axis direction, and the spatial phases of the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 are different by 90 degrees. In a real encoder, you can see that they are not offset from each other along the "y-axis" direction. Rather, they overlap each other, similar to the first and second sets of sensing elements shown in FIG. FIG. 11B corresponds to similar numbered or named components of FIG. 11A and / or includes several numbered and / or named components that may operate similarly or identically. Can be understood in the same way unless otherwise instructed. The second detection element set SETSEN-Ph90 in FIG. 11B can be regarded as unchanged from the description of FIG. 11A. Therefore, in the following description of FIG. 11B, only specific differences in the configuration of the first detection element set SETSEN-Ph0 will be emphasized.

The difference between the embodiment of the first detection element set SETSEN-Ph0 shown in FIG. 11B and the embodiment shown in FIG. 11B can be briefly explained as follows. In the embodiment shown in FIG. 11B with respect to the position of FIG. 11A, the first portion SETSEN-Ph0sub1 moves to the left by (W1) / 2, and the second portion SETSEN-Ph0sub2 moves to the right by (W1) / 2. is doing. Output signal connections are currently provided on the rightmost sensing elements SEN4 and SEN6 and remain associated with the trace of the positive loop for conceptual continuity with FIG. 11A. Based on the above description, there is no difference in the operation of the first detection element set SETSEN-Ph0 in the relationship between the signal output and the position, as shown in FIGS. 11B and 11A.

Embodiments of the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 shown in FIG. 11B can be comprehensively described as follows. The second detection element set SETSEN-Ph90 corresponds to the second spatial phase and includes features A1, B1, C1, D1, and E1. Then, the loops of the first separation portion SETSEN-Ph90sub1 and the second separation portion SETSEN-Ph90sub2, which are closest to each other (for example, SEN4 and SEN5), are configured to have the same loop polarity. There is. All of these are the same as described for FIG. 11A. In contrast, the first detection element set SETSEN-Ph0 corresponding to the first nominal spatial phase Ph0 includes feature E1 in addition to features A1, B1, C1, D1 included in FIG. 11A. The feature E1 is provided because the first separation portion SETSEN-Ph90sub1 and the second separation portion SETSEN-Ph90sub2 separated by a gap equal to or larger than one width of the positive loop SEN or the negative loop SEN are provided. It is clear that they are doing. The positive loop effective region EffASEN or the negative loop effective region EffASEN of the second detection element set SETSEN-Ph90 is not located in the gap.

The first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 can be further described as follows. The second detection element set SETSEN-Ph90 corresponds to a nominal spatial phase Ph90 that is 90 degrees different from the nominal spatial phase Ph0 of each of the first detection element sets SETSEN-Ph0. In the first detection element set SETSEN-Ph0, the loops of the first separation part SETSEN-Ph0sub1 and the second separation part SETSEN-Ph0sub2, which are closest to each other (for example, SEN4 and SEN5), are opposite to each other. It is configured to have the loop polarity of. The first detection element set has a first region center of gravity of its entire detection element effective region located along the measurement axis between its first and second adjacent portions. Each of the second detection element sets SETSEN-Ph90 is a second region of the entire detection element effective region located along the measurement axis between the first separation unit SETSEN-Ph90sub1 and the second separation unit SETSEN-Ph90sub2. It has a center of gravity CEN-SETSEN-Ph90. In the first and second detection element sets, the first region center of gravity CEN-SETSEN-Ph0 and the second region center of gravity CEN-SETSEN-Ph90 are arranged at the same position along the measurement axis direction.

The above description describes the region centroid of each of the two detection element sets by including feature E1 in one (as in FIG. 11A) or both (as in FIG. 11B) of each of the two detection element sets. It shows that the alignment becomes easy. Based on the above description, it will be understood that the embodiment shown in FIG. 11B provides all the various advantages outlined above with reference to FIG. 11A.

FIG. 12 is a first spatial phase Ph0 and a first exemplary configuration of a set of sensing elements configured according to a predetermined relational principle of the first type disclosed herein. It is a top view which shows the specific side surface of the 1st detection element set SETSEN-Ph0 and the 2nd detection element set SETENS-Ph90 corresponding to the spatial phase Ph90 of 2. For the sake of explanation, the spatial phase Ph0 of the first detection element set and the spatial phase Ph90 of the second detection element set differ by 90 degrees. The first set SETSEN-Ph0 and the second set SETSEN-Ph90 are offset from each other along the vertical direction in FIG. In a real encoder, you can see that they are not offset from each other along the "y-axis" direction. Rather, they overlap each other, similar to the first and second sets of sensing elements shown in FIG. FIG. 12 comprises several numbered and / or named components that correspond to and / or may operate similarly or identically to the similarly numbered or named components of FIG. 11A. Can be understood in the same way unless otherwise instructed. Therefore, in the following description with respect to FIG. 12, only specific differences in the configurations of the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 will be emphasized.

The difference between the embodiment of the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 shown in FIG. 12 and the embodiment shown in FIG. 11A can be briefly explained as follows. .. In each of the detection element sets shown in FIG. 12, the pair of detection elements SEN1 and SEN2 of their first part SETSEN-Ph0sub1 and SETSEN-Ph90sub1 is not to the right as in FIG. 11A, but to their nominal spatial phase. It is shifted to the left by (W1) / 4K. On the contrary, in each detection element set shown in FIG. 12, the pair of the detection elements SEN5 and SEN6 of their second part SETTEN-Ph0sub2 and SETSEN-Ph90sub2 is not on the left as shown in FIG. 11A, but their nominal spatial phase. It is shifted to the right by (W1) / 4K.

As outlined above, the implementation of the "shifted pair" of detection elements SEN shown in FIG. 11B in either the first detection element set SETSEN-Ph0 or the second detection element set SETSEN-Ph90 is any detection element set. In this case as well, it can be comprehensively explained as follows. According to the first aspect of the embodiment, at least the first (second) detection element set SETSEN-Ph0 (SETSEN-Ph90) corresponding to each nominal spatial phase Ph0 (Ph90) has features A1, B1, C1. , And D1, and according to feature C1, a plurality of pairs of detection element effective regions of adjacent positive and negative loops are shifted in the first direction along the measurement axis direction by (W1) / 4K. The same number of pairs of detection element effective regions of adjacent positive and negative loops are shifted along the measurement axis direction by (W1) / 4K in a direction opposite to the first direction.

Either the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 can be further described as follows. According to a second aspect of the embodiment, two respective pairs of adjacent loops at the opposite ends of each first set of sensing elements (eg, a pair of SEN1 and SEN2, and a pair of SEN7 and SEN8). Pairs) have detection element effective regions of positive and negative loops shifted in the same direction along the measurement axis in each of those two pairs.

Further, the second detection element set SETSEN-Ph90 shown in FIG. 12 includes the feature E1 in addition to the features A1, B, C1 and D1, and has the region center of gravity CEN-SETENS-Ph0 and CEN-SETSEN-Ph90. Is aligned with.

Based on the above description, it will be understood that the embodiment shown in FIG. 12 provides all the various advantages outlined above with reference to FIG. 11A. It can provide additional benefits such as: As described above, the aligned region centroids of the embodiment shown in FIG. 11A have static or dynamic pitch shifts in the operating gaps and signal intensities of the first and second detector sets, respectively. It has the advantage of being similarly affected by, which eliminates most of the errors that can occur due to pitch shifts. However, all of the left half detection elements SEN in the embodiment are shifted in their respective first directions by shifting the spatial phase of (W1) / 4K, and all of the right half detection elements SEN in the embodiment are (W1). ) / 4K It can be understood that they are shifted in opposite directions by shifting the spatial phase. Due to static or dynamic pitch shifts, the contributions of the right and left halves of the signal are unbalanced. As a result, the contribution of the signal due to the shift of the spatial phase in the opposite directions of the right half and the left half becomes unbalanced to some extent, and the sensitivity of the position error to the pitch shift becomes small. In contrast, in the embodiment shown in FIG. 12, the pair of sensing elements SEN are shifted in both directions in both the right and left halves of the embodiment, spatially due to static or dynamic pitch shifts. The phase error is reduced or eliminated. As one reference example, in the embodiment shown in FIG. 12, since the detection elements SEN1 and SEN8 at the opposite ends of the right half and the left half are shifted in the same direction by (W1) / 4K, they are totaled. It will be appreciated that both the amplitude and spatial phase of the signal contribution do not nominally change due to pitch shifts.

It should be understood that the first aspect described above can provide some of the advantages described above in a particular embodiment without using the second aspect. However, in various embodiments, it may be most advantageous to use the first and second aspects in combination, as shown in FIG.

FIG. 13 is a predetermined of the first type disclosed herein to provide a spatially filtered signal for use in the detector of an electromagnetic induction encoder as shown in FIG. The specific aspects of each detection element set SETSEN-Ph90 corresponding to each spatial phase Ph90, which is the sixth exemplary configuration of the detection element set configured according to the relational principle of FIG. 5 is a plan view showing the magnetic field generation coil FGC and the scale pattern 1380, including various dimensions that characterize the detection element configuration according to the principles disclosed herein. FIG. 13 corresponds to similar numbered or named components of FIGS. 9 and 12 and / or includes several numbered and / or named components that may operate similarly or identically. , These can be understood in the same way unless otherwise instructed. In particular, the configurations of the detection element sets SETSEN-Ph90 shown in FIGS. 13 and 12 are similar in that features A1, B1, C1, D1 and E1 are both implemented in the same manner. Both implement the first and second aspects of the "shifted pair" configuration described above with reference to FIG. 12 in a similar manner. Therefore, in the following description, only specific differences in the detection element set SETSEN-Ph90 relating to the adaptation to operate in the detector 1367 in conjunction with the "two-track" magnetic field generation coil FGC and the scale pattern 1380. Will be emphasized and explained.

The detector 1367 is arranged in a "two-track" configuration that can be understood based on the following brief description, and is incorporated herein by reference in its entirety. It can be understood based on a similar embodiment disclosed in No. 199 (Patent No. 199). Simply put, the scale pattern 1380 includes signal modulation elements SMEs arranged on the first track FPT and the second track SPT, respectively, extending along the measurement axis direction MA, as shown in the figure. The magnetic field generation coil FGC surrounds a first portion surrounding the first internal region portion FINTA aligned with the first track FPT and a second internal region portion FINTA aligned with the second track SPT. It is configured to have two parts. The connection between the parts of the magnetic field generation coil FGC and the current flow will be understood based on the example of the current flow arrow shown in FIG.

In this embodiment, according to the previously disclosed principle, the first detection element set SETSEN-Ph0 includes two separate parts SETSEN-Ph90sub1 and SETSEN-Ph90sub2. These layouts have been slightly devised to improve compatibility with the two-track embodiment so that those skilled in the art can understand. The first detection element set SETSEN-Ph0 corresponding to the nominal spatial phase Ph0nom extends laterally across the first internal region portion FINTA and the second internal region portion FINTA in the measurement axial direction MA, respectively. The first detection element effective region portion FEffASEN and the second detection element effective region corresponding to the portion of the detection element SEN that is aligned with or overlaps the first internal region portion FINTA and the second internal region portion FINTA. It may include a conductive loop that defines the partial SEffASEN. Therefore, the contribution of the detection signal generated in each conductive loop is a combination of the contributions of the respective detection signals from the first detection element effective region portion FEffASEN and the second detection element effective region portion SEffASEN. Compared with the above description of FIG. 9, the total of the first detection element effective region portion FEffASEN and the second detection element effective region portion SEffASEN of the detection element SEN can be interpreted as the detection element effective region EffASEN.

In the embodiment shown in FIG. 13, the scale pattern 1380 has a signal modulation element SME (or a signal modulation element partial SME) periodically arranged on the first track FPT according to the wavelength W1 and a th-order according to the wavelength W1. It is composed of a signal modulation element SME (or a signal modulation element partial SME) periodically arranged on the second track SPT, and the periodic arrangement of the first track FPT and the second track SPT is only (W1) / 2. It is relatively offset. Further, the magnetic field generation coil FGC is configured to generate a magnetic flux change of the first polarity in the first internal region portion FINTA and to generate a magnetic flux change of the opposite second polarity in the second internal region portion FINTA. Will be done.

The nature of the contribution of the combined detection signals, in combination with the overlapping signal modulation element SMEs, is the paired reference numerals "+, +" or "+,-" or "inside each detection element SEN of FIG. It is clarified by "-,-" or "-, +". The first reference numeral in the pair indicates the loop polarity of the detection element, and the second reference numeral indicates the polarity of the magnetic flux generated in the corresponding internal region portion. As an example, in the detection element SEN2, the signal contribution from the first detection element effective region portion FEffASEN is a nominal positive contribution that is not reduced by the overlapping signal modulation element SMEs. The signal contribution from the second detection element effective area FEffASEN is the nominal negative electrode contribution (due to the negative flux), but this contribution is reduced or substantially eliminated by the overlapping signal modulation element SMEs. .. As a result, the net signal contribution of the detection element SEN2 to the illustrated scale position is the net signal contribution. The signal contribution of the other sensing element SEN and / or the signal contribution for other scale positions can be understood by analogy with the above description and / or as detailed in patent '199. ..

As shown above, the sum of the first detection element effective region portion FEffASEN and the second detection element effective region portion SEffASEN of the detection element SEN is interpreted as the detection element effective region EffASEN in the two-track embodiment. be able to. This interpretation is appropriately applied in determining the average dimension DSENavg of the sensing elements outlined in the two-track configuration principle or feature B1.

With respect to an additional aspect of the interpretation of the sensory element average dimension DSENavg outlined in Principles or Features B1, in the case of a two-track configuration, it is aligned with or overlaps with two internal regions (eg FINTA and SINTA). For the detection element effective region EffASEN of each detection element, the effective y-axis dimension EffYSEN along the y-axis direction, which is the sum of the dimensions of one or more internal regions (for example, FINTA and SINTA) orthogonal to the measurement axis direction MA. May be defined as having. In the specific embodiment shown in FIG. 13, the average dimension DSENavg (= EffASEN / EffYSEN) of the detection element according to the above interpretation is illustrated so as to fall within the range of 0.33 * W1 ± 15%, which is the principle. Alternatively, it conforms to the explanation so far regarding the feature B1.

The first or second type of embodiment shown herein and further disclosed herein with reference to the two-track configuration shown in FIG. 17 below is only exemplary. It will be understood that it is not limited. More generally, those skilled in the art who have benefited from this disclosure and the teachings of this specification will be subject to certain relational principles or features of type 1 or type 2 disclosed and claimed herein. Accordingly, various spatial filtering configurations can be adapted for use in various other two-track embodiments as disclosed in Japanese Patent No. 199.

It is understood that the detection element set SETSEN disclosed in the various embodiments of the first type described above with reference to FIGS. 9 to 13 is merely exemplary and not limiting. Will. For example, in any of the detection element set SETSEN, the resulting detection element set SETSEN comprises at least one of the features A1, B1, and C1 and features D1 and E1 of the predetermined relationship as described above. It may be modified to include an additional detection element SEN (or, in certain disclosed embodiments, a smaller number of detection elements), provided that it is in such a shape and position.

Further, feature D1 is included in each of the embodiments shown in FIGS. 9 to 13, but is required in all embodiments provided that feature E1 is included in at least one set of each sensing element. It is not said that. As one specific example with reference to FIG. 11A, the shift directions of all the detection elements SEN in the detection element set SETSEN-Ph0 are reversed, and all of the detection elements SEN shown in FIG. 11A are shown in FIG. When replaced with the detection element SEN (maximum dimension DSENmax is about 0.5 * W1), the resulting encoder can be described as follows. The encoder includes a plurality of respective detection element sets (for example, SETSEN-Ph0 and SETSEN-Ph90) corresponding to a plurality of respective spatial phases (for example, Ph0 and Ph90), and each of the detection element sets is characterized by A1 and B1. , And C1 (eg, SETSEN-Ph0 does not contain feature D1 or E1), and at least one of each of the plurality of detection element sets further comprises at least feature E1 (eg, SETSEN-Ph90). The electromagnetic induction encoder then provides a potentially unwanted third-order spatial harmonic detection signal component that can contribute to a determined relative position error between the detector and the scale pattern. It is configured to provide a plurality of spatially filtered detection signals that can be used to reduce or suppress potentially unwanted K-th (fifth) spatial harmonic detection signal components. The resulting encoder can be further described as follows. Each of the plurality of respective detection element sets (eg, SETSEN-Ph0 and SETSEN-Ph90) has a region center of gravity of the entire detection element effective region located within the range along the measurement axis, and each of the plurality of detection elements. The detection element set is configured such that the centers of gravity of their respective regions are nominally located at the same location along the measurement axis direction. Further, the resulting encoder includes each positive or negative loop contained in any one of the plurality of respective detection element sets in the same one of the plurality of respective detection element sets. It may be configured to provide each detection element effective region EffASEN that does not overlap with the detection element effective region EffASEN of each positive or negative loop.

Further, if necessary, it is also possible to configure a similar three-phase encoder so as to include three detection element sets having the features A1, B1 and C1, in which case at least two detection element sets. Is equipped with the feature E1.

Thus, although preferred embodiments of the first type have been illustrated and described, those skilled in the art will appreciate a number of variations in the arrangement of features illustrated and described based on the present disclosure.

14-17 are such that the detection element SEN provides a spatially filtered signal for use in a detector (eg, 1467, 1567, 1767, etc.) of an electromagnetic induction encoder as shown in FIG. Partially concrete, showing aspects of various exemplary configurations of a sensing element set SETTEN configured or arranged according to a predetermined relational principle of the second type disclosed herein as formed in. It is a target, partially schematic, plan view. Compatible magnetic field generation coils FGC and scale patterns (eg 980, 1380) are also drawn. According to the promises used herein, an embodiment that conforms to a predetermined relational principle of the second type (discussed in more detail below) may be abbreviated as the second type of embodiment. be.

The principles outlined below with reference to FIGS. 9-13 are the potential third, fifth, seventh, or ninth spatial harmonics in the detection signal in various alternative embodiments. It is advantageous to arrange the detection element SEN to spatially filter the wave component, and the dimension DSENavg of the detection element SEN is configured to spatially filter the potential third harmonic component in the detection signal. As such, when used in combination with sizing the detector SEN according to the principles outlined above, the detector SEN to spatially filter potential fifth-order spatial harmonic components. Is particularly advantageous for forming. However, its use is not limited to the examples disclosed below. More generally, these principles, in addition to those disclosed herein (eg, as known in the prior art), are the configurations and signal modulations of various other detector set SETSENs. It can be used in combination with the device SME and can still provide great advantages.

FIG. 14 is a second type of predetermined specification disclosed herein to provide a spatially filtered signal for use in the detector of an electromagnetic induction encoder as shown in FIG. The first detection element set SETSEN-Ph90 corresponding to the first spatial phase Ph90, which is the first exemplary configuration of the detection element set configured according to the relational principle of A particular aspect of (referred to as), along with the first compatible magnetic field generation coil FGC and scale pattern 980 shown in FIG. 9, characterizes a variety of detector configurations according to the principles disclosed herein. It is a top view which shows including the dimension. FIG. 14 corresponds to similar numbered or named components of earlier figures, in particular FIG. 9 and / or FIG. 11A, and / or some numbers and / or names that may operate similarly or identically. Includes components marked with, which can be similarly understood unless otherwise indicated. Simply put, the overall operation of the embodiment shown in FIG. 13 and the various elements therein can be understood by analogy with the description of FIGS. 9 and 11A (and others applicable) above. can. The biggest difference between the detection element set SETSEN-Ph90 shown in FIGS. 14 and 11A is that each shape of the detection element SEN shown in FIG. 14 is predetermined for the purpose of providing desired spatial filtering in each detection element SEN. It is to include two "in-loop" shift ratios that are shifted in opposite directions by quantity. When this feature is implemented in a second type of embodiment, the desired spatial filtering is achieved without the need to implement the principles or function C1 required in the first type of implementation. Since the overall detection operation of the detection element set SETSEN-Ph90 shown in FIGS. 14 and 11A is otherwise similar, the following description describes the detection element set SETSEN-Ph90 shown in FIGS. 14 and 11A. Of the configurations of the above, only specific aspects related to the shape of the detection element SEN and the shift ratio in the loop included therein will be emphasized and described.

In various embodiments of the second type configured to provide spatially filtered detection signals, as disclosed below with reference to FIGS. 14-17, for each nominal spatial phase. Each corresponding at least first set of sensing elements comprises features A2 and B2 as defined below.

A1) A plurality of positive loops corresponding to the first winding direction or polarity and the same number of negative loops corresponding to the second winding direction or polarity opposite to the first winding direction or polarity are provided.

B2) At least half of the positive loop and at least half of the negative loop have detection element effective regions arranged in a predetermined in-loop shift relationship with respect to each nominal spatial phase of each detection element set. It is configured as follows.

In the loop shift relationship, in each such loop, the shift ratio in the loop up to half of the effective region of the detection element is measured in the first direction by (W1) / 4K in relation to the respective nominal spatial phase. The shift ratios in the loop, which are shifted along the axial direction and are nominally the same in the effective region of the detection element, are measured in the direction opposite to the first direction by (W1) / 4K in relation to the respective nominal spatial phases. The shift ratios in the two loops are such that they are shifted relative to each other by (W1) / 2K, where K is 3, 5, 7, or. It is one of nine.

Thereby, the detection element set corresponding to each nominal spatial phase (SETSENPh0) can potentially cause an error in the determined relative position between the detector and the scale pattern. It has a practical configuration that provides a spatially filtered detection signal or a plurality of detection signals that can be used to reduce or suppress unnecessary K-th order spatial harmonic detection signal components.

As a result of implementing the above features A2 and B2, the detection element set SETSEN corresponding to each nominal spatial phase may thereby cause a determined relative position error between the detector and the scale pattern. In a practical configuration that provides a spatially filtered detection signal or multiple detection signals that can be used to reduce or suppress potentially unwanted K-order spatial harmonic detection signal components. It has become.

14 to 17 each include a "reference grid" as previously described herein, and the center positions of the first track effective region FEffASEN and the second track effective region SEffASEN of each detection element SEN are as follows. As described in more detail in, in order to explain how each detection element SEN is configured according to feature B2, it is indicated by the position of the dashed centerline CLSEN.

Returning to further discussion of the embodiments shown in FIG. 14, based on the reference grid and centerline indicators shown in FIG. 14, the detection element set SETSEN shown in FIG. 14 has the configuration principle outlined above or as follows: It will be appreciated that features A2 and B2 are satisfied. In the embodiment shown in FIG. 14, each sensing element set SETSEN-Ph90 corresponding to each nominal spatial phase Ph90 has a plurality of positive loops (inside the loop, "+" corresponding to the first winding direction or polarity. (Indicated by ")" and the same number of negative electrode loops (indicated by "-" inside the loop) corresponding to the second winding direction or polarity opposite to the first winding. In the embodiment shown in FIG. 14, all the positive loops and all the negative loops have the detection element effective region EffASEN in a predetermined loop with respect to each nominal spatial phase Ph90nom of each detection element set SETSEN-Ph90. It is configured to be arranged in a shift relationship. The intra-loop shift relationship is such that in each loop SEN, the intra-loop shift ratio ILSP up to half of the effective region of the detection element is the first in relation to the respective nominal spatial phase Ph90nom (W1) / 4K. The shift ratio ILSP in the loop, which is shifted in the direction along the measurement axial direction MA and is nominally the same in the effective region of the detection element, is the first direction by (W1) / 4K in relation to each nominal spatial phase Ph90nom. The configuration is such that the two in-loop shift ratios ILSPs (eg, FEffASEN and SEffASEN) are shifted in opposite directions along the measurement axis, thereby shifting relative to each other by (W1) / 2K. Has, K is one of 3, 5, 7, or 9. Each such detector SEN has two spatially filtered detection signal components (eg, two intra-loop shift ratio ILSPs (ie, FEffASEN) for K-th spatial harmonics that are 180 degrees out of phase with each other. And SEffASE)) are combined and configured to nominally cancel or suppress such K-th order spatial harmonic signal components in their combined signal contributions.

In the particular embodiment shown in FIG. 14, the in-loop shift ratio ILSP (eg, FEffASEN and / or SEffASEN) of the detection element SEN is nominally half of its detection element effective region EffASEN, thereby providing the best spatial filtering. Can be provided. However, as implied in the definition of feature B2, in some embodiments where the in-loop shift ratio ILSP is less than half the detection element effective region EffASEN, the spatial filtering provided is sufficient. There is.

In the specific embodiment shown in FIG. 14, in all of the positive loop SEN and all of the negative loop SEN, their detection element effective regions (for example, EffASEN = FEffASEN + SEffASEN) are arranged in a predetermined in-loop shift relationship. This can provide the best spatial filtering. However, as implied in the definition of feature B2, some such that only most of the positive and negative loops are configured by arranging the detection element effective regions in a predetermined intra-loop shift relationship. In some embodiments, the spatial filtering provided may be sufficient.

The entire detection element effective region EffASEN of the detection element SEN shown in FIG. 14 is defined as outlined above herein. This refers to a region within the detection element SEN that is aligned with or overlaps with one or more internal regions (eg, INTA in FIG. 14) and is one or more internal regions orthogonal to the measurement axis direction MA. It may be defined to have an effective y-axis dimension EffYSEN along the y-axis direction, which is the sum of the dimensions (eg, INTA in FIG. 14). In a specific embodiment of the second type shown in FIG. 14, K = 5, and the detection element SEN has a detection element average dimension DSENavg along the measurement axis direction within the range of 0.33 * W1 ± 15%. Therefore, each detection element set corresponding to each nominal spatial phase (SETSENPh0) is thereby potentially unwanted third-order spatial harmonic detection signal component and potential unwanted. It is configured to provide a spatially filtered detection signal or a plurality of detection signals that can be used to reduce the fifth-order spatial harmonic detection signal component. However, as shown above, this embodiment is exemplary and not limiting. In various other embodiments, K may be 5, 7, or 9. In such an embodiment, each detection element set configured to include features A2 and B2 can thereby contribute to a determined relative position error between the detector and the scale pattern. Spatial filtered, which can be used to reduce potential unwanted third-order spatial harmonic detection signal components and potential unwanted Kth-order spatial harmonic detection signal components. It is configured to provide a detection signal or a plurality of detection signals.

In the particular embodiment shown in FIG. 14, the sensing element set SETSEN-Ph90 comprises two similar subsets or partial SETSEN-Ph0sub1 and SETSEN-Ph0sub2 arranged mirror-symmetrically with each other. One advantage of this configuration is the lateral offset shift (ie, translational detection along the y-axis) as compared to using one of the partial SETSEN-Ph0sub1 and SETSEN-Ph0sub2 alone. The sensitivity of the position error to the portion 1667 and / or the deviation of the scale pattern 980) can be reduced or eliminated. However, such a two-part configuration is exemplary and not limiting. For example, any portion of either SETSEN-Ph0sub1 or SETSEN-Ph0sub2 individually comprises features A2 and B2 (eg, as is or by duplicating the pattern of their sensing element SEN to increase its length). By itself, it can be used alone, and the advantages of spatial filtering described above are still available in various embodiments.

FIG. 15 is a second type of predetermined specification disclosed herein to provide a spatially filtered signal for use in the detector of an electromagnetic induction encoder as shown in FIG. The first detection element set SETSEN-Ph90 (abbreviated in some contexts below) corresponding to the first spatial phase Ph90, which is the second exemplary configuration of the detection element set configured according to the relational principle of It is a plan view showing a specific aspect of (referred to as) together with the first compatible magnetic field generation coil FGC and scale pattern 980 shown in FIG. FIG. 15 corresponds to similar numbered or named components of FIG. 14 and / or includes several numbered and / or named components that may operate similarly or identically. Can be understood in the same way unless otherwise instructed. Therefore, in the following description, only specific differences in the configurations shown in FIGS. 15 and 14 will be emphasized.

Simply put, the overall operation of the embodiment shown in FIG. 15 and the various elements therein can be understood by analogy with the description of FIG. 14 (and others applicable) above. The only important difference between the detector set SETSEN-Ph90 shown in FIGS. 15 and 14 is that some orientations of the detector SEN shown in FIG. 15 are oriented as shown in FIG. It is a point that is inverted or "inside out" compared to. In particular, the pair of detection elements SEN1 and SEN2 and the pair of detection elements SEN5 and SEN6 are inverted or turned inside out as compared with their orientations, as shown in FIG.

The embodiment of the detection element set SETSEN-Ph90 shown in FIG. 15 can be comprehensively described as follows without referring to FIG. Each of the first detection element sets SETSEN-Ph90 is configured according to features A2 and B2, and is configured to have a nominally congruent shape with respect to the effective region of those detection elements. Positive electrodeposition configured to have a nominally congruent shape with respect to at least the first pair of loops (eg, a pair of SEN1-SEN2 or a pair of SEN7-SEN8) and their sensing element effective regions. It comprises at least a second pair of negative loops (eg, a pair of SEN3-SEN4 or a pair of SEN5-SEN6), and the congruent shapes in the first and second pairs are nominally mirror images of each other. The first and second pairs of positive and negative loops are arranged adjacent to each other (eg, a pair of SEN1-SEN2 and a pair of SEN3-SEN4, or a pair of SEN5-SEN6 and SEN7-SEN8. ).

Configurations with such "mirror image pairs" may, in some embodiments, improve accuracy and / or robustness to a particular misalignment. For example, in pitch misalignment combined with lateral offset and pitch misalignment combined with yaw misalignment (that is, rotation of the detector 1767 or scale pattern 980 around the Z axis), position error detection is reduced. May have been done.

The embodiment of the detection element set SETSEN-Ph90 shown in FIG. 15 can be further described as follows. Each of the first detection element sets, SETSEN-Ph90, is at least a positive and negative loop configured to have a nominally congruent shape with respect to its detection element effective region EffASEN within the first end pair. Positive and negative loops configured to have a nominally congruent shape for the first end pair (eg, SEN1-SEN2 pair) and its sensing element effective region EffASEN within the second end pair. With at least a second end pair (eg, a pair of SEN7-SEN8), the nominally congruent shape of the first end pair and the second end pair is the first end pair and the first. It is also nominally congruent between the two end pairs. It will be appreciated that the first and second end pairs are located at the first and second ends of each of the first detection element sets SETSEN-Ph90.

The advantage of a configuration with "mirror image pairs" may be enhanced in some embodiments if further congruent end pairs are provided, as shown in the overview above and FIG. .. However, even configurations with "mirror image pairs" that do not include congruent end pairs (eg, configurations with more detection elements and more mirror image pairs than are shown in FIG. 15). It should be understood that it can provide the great advantages mentioned above.

FIG. 16 is a plan view showing a specific aspect of the second detection element set SETSEN-Ph0 corresponding to the second spatial phase Ph0 (indicated as Ph0nom in FIG. 16). It is a third exemplary configuration of a set of sensing elements configured according to a predetermined relational principle of the second type disclosed herein. It is shown in FIG. 16 together with the first detection element set SETSEN-Ph90 corresponding to the second spatial phase Ph90 illustrated in FIG. For the sake of explanation, the first detection element set SETSEN-Ph90 and the second detection element set SETSEN-Ph0 are offset from each other in the vertical direction in FIG. These are arranged in a quadrature relationship that can operate along the measurement axis direction, and the spatial phases of the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 are different by 90 degrees. In a real encoder, you can see that they are not offset from each other along the "y-axis" direction. Rather, they overlap each other, similar to the first and second sets of sensing elements shown in FIG. FIG. 16 corresponds to similar numbered or named components of FIG. 15 and / or includes several numbered and / or named components that may operate similarly or identically. Can be understood in the same way unless otherwise instructed. The first detection element set SETSEN-Ph90 in FIG. 16 can be regarded as unchanged from the description of FIG. Therefore, in the following description of FIG. 16, only specific aspects of the configuration of the second detection element set SETSEN-Ph0 will be emphasized.

Briefly explaining the difference between the embodiments of the second detection element set SETSEN-Ph0 and the first detection element set SETSEN-Ph90 shown in FIG. 16, the first portion SETSEN-Ph0sub1 is compared with the first portion SETSEN-Ph90sub1. (W1) / 4 is moved to the right, and the second portion SETSEN-Ph0sub2 is moved to the left by (W1) / 4 as compared with the first portion SETSEN-Ph90sub1. As a result, the effective loop polarity of the detection element SEN is shown in FIG. The output signal connection is provided on the sensing element SEN5 and remains associated with the trace of the positive loop for conceptual continuity with FIG. In the particular embodiment shown in FIG. 16, the first portion SETSEN-Ph0sub1 and the second portion SETSEN-Ph0sub2 are connected by series connection in the aligned trace zone ATZ in the manner already outlined with reference to FIG. Only one output signal connection location is required.

Embodiments of the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 shown in FIG. 16 can be comprehensively described as follows. The first detection element set SETSEN-Ph90 corresponding to the nominal spatial phase Ph90 is configured according to features A2 and B2, and has a first separation part SETSEN-Ph90sub1 having the same number of positive and negative loops, and a first A second separation part SETSEN- that is nominally aligned with the separation part SETSEN-Ph90sub1 of 1 along the measurement axis direction and has the same number of positive and negative loops as the first separation part SETSEN-Ph90sub1. It is composed of two parts including Ph90sub2. The first separation part SETSEN-Ph90sub1 and the second separation part SETSEN-Ph90sub2 are separated by a gap located between them along the measurement axis direction, and the gap is positive along the measurement axis direction MA. It has at least the same width as either the loop or the negative loop, and the effective region EffASEN of the positive loop or the effective region EffASEN of the negative loop of each of the first detection element sets SETSEN-Ph90 is not located in the gap. Each of the first detection element sets SETSEN-Ph90 is configured such that the loops of the first and second separation portions closest to each other (that is, SEN4 and SEN5) have the same loop polarity. Has been done.

In the embodiment shown in FIG. 16, a second detection element set SETSEN-Ph0 corresponding to the nominal spatial phase Ph0, which is 90 degrees different from the nominal spatial phase Ph90, is further provided. The second detection element set, SETSEN-Ph0, is configured according to features A2 and B2, which is also composed of two parts. The second partial configuration is nominally aligned with the first adjacent portion SETSEN-Ph0sub1 having the same number of positive and negative loops and the first adjacent portion SETSEN-Ph0sub1 along the measurement axis direction. It includes a second adjacent portion SETSEN-Ph0sub2 having the same number of positive and negative loops as the first adjacent portion SETSEN-Ph0sub1. The first adjacent portion SETSEN-Ph0sub1 and the second adjacent portion SETSEN-Ph0sub2 are located closer to each other along the measurement axis direction than the width of one of the positive or negative loops. The loops of the first adjacent portion and the second adjacent portion that are closest to each other (that is, SEN4 and SEN5) have opposite loop polarities.

As shown in FIG. 16, the first detection element set SETSEN-Ph90 is a total detection element located between the first separation part SETSEN-Ph90sub1 and the second separation part SETSEN-Ph90sub2 along the measurement axis MA. Having a first region center of gravity CEN-SETSEN-Ph90 of the effective region, the second detection element set SETSEN-Ph0 has its first adjacent portion SETSEN-Ph0sub1 and second adjacent portion SETSEN along the measurement axis MA. It has a second region center of gravity CEN-SETSEN-Ph0 of the effective region of all detection elements located between -Ph0sub2. As shown in FIG. 16, the first detection element set SETSEN-Ph90 and the second detection element set SETSEN-Ph0 have the first region center of gravity CEN-SETENS-Ph90 and the second region center of gravity CEN-SETSEN-, respectively. Ph0 is arranged at the same position along the measurement axis direction.

The embodiments shown in FIG. 16 include potentially unwanted third-order spatial harmonic detection signal components that may contribute to a determined relative position error between the detector and the scale pattern. It is configured to provide a spatially filtered detection signal or multiple detection signals that can be used to reduce potentially unwanted K-order spatial harmonic detection signal components. It will be understood based on the explanation up to. In addition, it also includes other features that eliminate positioning errors associated with aligned region centroids and various types of misalignment. Further, each positive or negative loop (for example, each detection element SEN) included in one of the first detection element set SETSEN-Ph90 or the second detection element set SETSEN-Ph9 is a first or second detection element set. Each detection element effective region EffASEN that does not overlap with the detection element effective region EffASEN of each of the other positive or negative loops included in the same one of the detection element sets of the above is configured to provide.

Generally speaking, the second type of embodiment outlined above with reference to FIGS. 14, 15, and 16 is less complex, more powerful, and more economical than prior art spatial filtering detectors. It will be appreciated that the layout of the detectors that can be manufactured in a productive manner can be used to provide an unprecedented level of spatial filtering that suppresses multiple unwanted spatial harmonic signal components.

FIG. 17 is a second type of predetermined specification disclosed herein to provide a spatially filtered signal for use in the detector of an electromagnetic induction encoder as shown in FIG. A specific aspect of the first detection element set SETSEN-Ph90 corresponding to each spatial phase Ph90, which is a fourth exemplary configuration of the detection element set configured according to the relational principle of FIG. 13, is shown in FIG. FIG. 5 is a plan view shown with a second compatible magnetic field generation coil FGC and scale pattern 1380. FIG. 17 corresponds to a similar numbered or named component of the two-track configuration shown in FIG. 13 and / or some numbered and / or named configurations that may behave similarly. It is a "two-track" configuration that includes elements, which can be similarly understood unless otherwise indicated. The configuration of the detection element set SETSEN-Ph90 shown in FIG. 17 is illustrated and described with reference to FIGS. 15 and 16 in that both mount features A2 and B2 and the detection element SETSEN is arranged in a similar manner. It is similar to the detection element set SETSEN-Ph90. The conductor layout of the detection element SEN in FIG. 17 is adapted for collaboration with the two-track magnetic field generation coil FGC and scale pattern 1380, as can be understood by analogy with the description of FIG. 13 above. ing.

Based on the above description of similarity to previous figures, the embodiments shown in FIG. 17 and their various advantages are understood by analogy with the previous description of FIGS. 13, 14, 15, and 16. can do. Therefore, it is not necessary to explain in more detail here.

It will be appreciated that the detection element set SETSEN in the various embodiments of the second type described above with reference to FIGS. 13-17 is only exemplary and not limiting. For example, either a set of detectors, a subset, or a portion, is formed and configured such that the resulting set of detectors, SETSEN, conforms to features A2 and B2 of a given relationship, as outlined above. Subject to this, it can be modified to include an additional detection element SEN.

Further, in the various embodiments disclosed above, the detection elements constituting the detection element effective region may be combined with other detection element effective regions of other conductive loops or conductive loop portions included in the respective detection element sets. Although configured so that they do not overlap, such embodiments are exemplary and not limiting. Generally speaking, features A2 and B2 can be implemented in any desired sensing element arrangement, including overlapping arrangements commonly used in the prior art. In such an embodiment, the sensing element comprising features A2 and B2 may provide additional spatial filtering of the Kth order spatial harmonics as described above to enhance such embodiments. good.

As an example, the various embodiments described above correspond to K = 5 and are composed of detection elements having an average detection element dimension DSENavg within the range of 0.33 * W1 ± 15%. The combinations are exemplary and are not limiting, as will be apparent to those skilled in the art.

As another example, in the detection element set SETSEN-PH0 shown in FIG. 16, the gap between the portions is changed in the same manner as described with reference to the detection element set SETSEN-PH0 shown in FIG. , The two "separation" parts that provide the quadrature encoder configuration may be configured. Therefore, the general configurations of the first detection element set SETSEN-Ph0 and the second detection element set SETSEN-Ph90 shown in FIG. 16 are exemplary and not limited.

As another example, it is possible to configure each of the detection element sets of a three-phase encoder in a manner similar to any of the various embodiments of the second type described above. In such an embodiment, each of the plurality of respective detection element sets corresponding to the plurality of respective spatial phases is configured to include features A2) and B2), whereby the detection unit and the scale are provided. Spatial, which can be used to reduce or suppress potentially unwanted K-th order spatial harmonic detection signal components that can contribute to the determined relative positional error with and from the pattern. Is configured to provide a filtered detection signal.

Although preferred embodiments of the second type have been illustrated and described, those skilled in the art will appreciate a number of variations in the arrangement of features illustrated and described based on the present disclosure. Various alternative forms can be used to implement the predetermined relationship features A2 and B2 disclosed herein.

The principles disclosed and claimed herein are filed on March 23, 2020, with the various features disclosed in the incorporated literature and the disclosure of which is incorporated herein by reference in its entirety. Easily and preferably combined with the various features disclosed in the commonly assigned Simultaneously Assigned US Patent Application No. 16 / 286,842 entitled "TRANSMITTER AND RECEIVER CONFIGURATION FOR AN INDUCTIVE POSITION ENCODER". It will be understood that it can be done. Further embodiments can be provided by combining the various embodiments described above. All US patents and US patent applications referred to herein are incorporated herein by reference in their entirety. The embodiments may be modified to use various patent and application concepts, if desired, to provide further embodiments. These and other changes can be added to the implementation in the light of the detailed description above. Generally, in the following claims, the terms used should not be construed to limit the scope of the claims to the specific embodiments disclosed in the specification and claims, as such. The claims should be construed to include all possible embodiments, as well as the full range of entitled equivalents.

Claims (19)

An electromagnetic induction encoder that can be used to measure the relative position between two elements along the measurement axis direction.
Includes a periodic scale pattern that includes at least the first type of signal modulation element and has a spatial wavelength W1 that extends along the measurement axis and contains an effective region that extends along the measurement axis and is aligned or overlaps with the internal region of the magnetic field generation coil. Scale and
A detector that is mounted close to the periodic scale pattern and is configured to move along the measurement axis direction with respect to the periodic scale pattern.
A signal processing unit operably connected to the detection unit to provide a coil drive signal and specifying a relative position between the detection unit and the scale pattern based on the detection signal input from the detection unit. With,
The first type of signal modulation element comprises a plurality of conductive plates or a plurality of conductive loops arranged along the measurement axis direction corresponding to the spatial wavelength W1.
The detection unit
A magnetic field generation that is fixed to a substrate, surrounds an internal region of the signal modulation element that is aligned with the effective region of the periodic scale pattern during operation, and generates a magnetic flux change in the internal region in response to the coil drive signal. With the coil
It comprises at least one set of each sensing element, arranged along the measurement axis direction and fixed on the substrate, corresponding to each nominal spatial phase.
A member of the detection element set comprises a conductive loop or a conductive loop portion that defines a detection element effective region EffASEN corresponding to a portion of the detection element that is aligned with or overlaps the internal region. ,
The detection element set is configured to provide each detection signal according to the local influence on the magnetic flux change provided by the signal modulation element adjacent to the scale pattern, and corresponds to each nominal spatial phase. And
Each at least the first set of sensing elements corresponding to each nominal spatial phase comprises features A2 and B2 as defined below.
Feature A2 comprises a plurality of positive loops corresponding to the first winding direction or polarity and the same number of negative loops corresponding to the second winding direction or polarity opposite to the first winding direction or polarity. Prepare,
In feature B2, at least half of the positive loop and at least half of the negative loop are arranged so that the detection element effective region has a predetermined intra-loop shift relationship with respect to each nominal spatial phase of each detection element set. Is configured to be
The intra-loop shift relationship is such that in each such loop, the in-loop shift ratio up to half of the effective region of the detection element is in the first direction by (W1) / 4K in relation to the respective nominal spatial phase. The shift ratio in the loop, which is nominally the same in the effective region of the detection element, is shifted in the direction opposite to the first direction by (W1) / 4K in relation to the respective nominal spatial phases. It is shifted along the measurement axis direction, so that the shift ratios in the two loops are shifted by (W1) / 2K relative to each other, and K is 3, 5, It is one of 7 or 9 and
The set of detectors corresponding to each nominal spatial phase can thereby cause a determined relative position error between the detector and the scale pattern, potentially unwanted K-th order. An electromagnetic induction encoder having a practical configuration that provides a spatially filtered detection signal or multiple detection signals that can be used to reduce or suppress the spatial harmonic detection signal component. In feature B2, in the positive and negative loops formed by arranging the detection element effective regions in a predetermined in-loop shift relationship, the in-loop shift ratio is nominally half of those detection element effective regions. The electromagnetic induction type encoder according to claim 1, wherein the electromagnetic induction type encoder is characterized in that. The first aspect of the feature B2 is that all the positive electrode loops and the negative electrode loops are configured in a state in which the detection element effective regions thereof are arranged in a predetermined in-loop shift relationship. The electromagnetic induction encoder described. At least each of the first detection element sets is configured according to features A2 and B2, and has a positive electrode property and a negative electrode property which are configured to have a nominally congruent shape with respect to the effective region of the detection element. It comprises at least a first pair of loops and at least a second pair of positive and negative loops configured to have a nominally congruent shape with respect to the effective region of the sensing element. The congruent shape of the first and second pairs is nominally a mirror image of each other, and the positive and negative loops of the first and second pairs are arranged adjacent to each other. The electromagnetic induction type encoder according to claim 1. At least the first of the positive and negative loops in which each of the first set of sensing elements is configured to have at least a nominally congruent shape with respect to the effective region of the sensing element within the first end pair. And at least a second end pair of positive and negative loops configured to have a nominally congruent shape for the effective region of the detection element within the second end pair. The first and second end pairs are further configured to have a nominally congruent shape between the first end pair and the second end pair, and the first and second end pairs are the first. The electromagnetic induction encoder according to claim 4, wherein the electromagnetic induction encoder is located at the first and second ends of the respective detection element sets of the above. The electromagnetic induction encoder according to claim 1, wherein K = 5. Each of the detection elements included in each of the detection element sets configured to include features A2 and B2 is a total detection element that is aligned with the internal region or overlaps with one or more of the internal regions. Each said detection element set is defined to have an effective region EffASEN and an effective y-axis dimension EffYSEN along the y-axis direction, which is the sum of the dimensions of one or more internal regions perpendicular to the measurement axis direction. At least half of the detection elements included in the above are configured so that the average dimension DSENavg = (EffASEN / EffYSEN) of the detection elements along the measurement axis direction is within the range of 0.33 * W1 ± 15%. The detector set thereby provides a potentially unwanted third-order spatial harmonic detection signal component that can contribute to a determined relative position error between the detector and the scale pattern. It is characterized in that it is configured to provide a spatially filtered detection signal or a plurality of detection signals that can be used to reduce potential unwanted fifth-order spatial harmonic detection signal components. The electromagnetic induction type encoder according to claim 6. Each positive or negative loop included in each of the sensing element sets configured to comprise features A2 and B2 is another positive or negative loop included in each of the first sensing element sets. The electromagnetic induction type encoder according to claim 7, wherein each of the detection element effective regions EffASEN that does not overlap with the detection element effective region EffASEN of the negative electrode loop is provided. Each at least the first set of sensing elements corresponding to each nominal spatial phase is configured according to features A2 and B2 and is composed of two parts.
The configuration consisting of the two parts includes a first separation part having the same number of positive and negative loops, and a first separation part.
It is provided with a second separating portion that is nominally aligned with the first separating portion along the measurement axis direction and is composed of the same number of positive and negative loops as the first separating portion.
The first separation portion and the second separation portion are separated by a gap located along the measurement axis direction between the first separation portion and the second separation portion, and the gap is formed. The width is at least the same as that of either the positive electrode loop or the negative electrode loop along the measurement axis direction, and the effective region of the positive loop or the effective region of the negative loop of each of the first detection element sets is within the gap. The electromagnetic induction type encoder according to claim 1, wherein the electromagnetic induction type encoder is not located at. Equipped with either M1 or M2 below
The feature M1 is configured such that the first separation unit in each of the first detection element sets outputs a first detection signal, and the second separation unit in each of the first detection element sets. Is configured to output a second detection signal, the signal processing unit is at least partially based on the combination of the first and second signals, and the relative position between the detection unit and the scale pattern. Is configured to determine
In the feature M2, the first separation unit in each of the first detection element sets is connected in series with the second separation unit in each of the first detection element sets to form a composite signal, and the composite signal is formed in series. The connection is configured such that the signal contributions of the first and second separation units are added to the composite signal, and the signal processing unit is at least partially based on the composite signal and the detection unit. The electromagnetic induction encoder according to claim 9, wherein the electromagnetic induction encoder is configured to determine a relative position between the and the scale pattern. Each of the first detection element sets is configured such that the respective loops of the first and second separations closest to each other have the same loop polarity.
The electromagnetic induction encoder further includes at least each of the second detection element sets corresponding to each nominal space phase 90 degrees different from the nominal space phase of each of the first detection element sets, respectively. The detection element set of is configured to include features A2 and B2, and is composed of two parts.
The composition consisting of the two parts
A first adjacent portion with the same number of positive and negative loops,
It is provided with a second adjacent portion that is nominally aligned with the first adjacent portion along the measurement axis direction and is composed of the same number of positive and negative loops as the first adjacent portion.
The first and second adjacent portions are located closer to each other along the measurement axis direction than the width of one of the positive or negative loops, and the first and second adjacent portions closest to each other, respectively. Loops have opposite loop polarities and
Each of the first detection element sets has a first region center of gravity of its entire detection element effective region located along the measurement axis between the first and second separation portions.
Each of the second detection element sets has a second region center of gravity of its entire detection element effective region located along the measurement axis between the first and second adjacent portions.
The electromagnetic wave according to claim 9, wherein each of the first and second detection element sets has the center of gravity of the first and second regions arranged at the same position along the measurement axis direction. Inductive encoder. Each positive or negative loop included in one of the first or second detection element sets is each other contained in the same one of the first or second detection element sets. The electromagnetic induction type encoder according to claim 11, wherein each of the detection element effective regions EffASEN that does not overlap with the detection element effective region EffASEN of the positive electrode or negative electrode loop is provided. Each of the first detection element sets is configured such that the respective loops of the first and second separation portions closest to each other have the same loop polarity.
The electromagnetic induction encoder further includes at least each of the second detection element sets corresponding to each nominal space phase 90 degrees different from the nominal space phase of each of the first detection element sets, respectively. The detection element set of is configured according to features A2 and B2, and is composed of two parts.
The configuration consisting of the two parts includes a first separation part having the same number of positive and negative loops, and a first separation part.
It is provided with a second separating portion that is nominally aligned with the first separating portion along the measurement axis direction and is composed of the same number of positive and negative loops as the first separating portion.
The first and second separation portions are located farther from each other along the measurement axis direction than the width of one of the positive electrode or negative electrode loops, and are the closest to each other, respectively. Loops have opposite loop polarities and
Each of the first detection element sets has a first region center of gravity of its entire detection element effective region located along the measurement axis between the first and second separation portions.
Each of the second detection element sets has a second region center of gravity of its entire detection element effective region located along the measurement axis between the first and second separation portions.
The electromagnetic wave according to claim 9, wherein the first and second detection element sets have their respective first and second center of gravity of the region arranged at the same position along the measurement axis direction. Inductive encoder. The scale pattern comprises signal modulation elements arranged on the first and second tracks extending along the measurement axis direction, respectively.
The magnetic field generation coil is configured to surround a first internal region portion aligned with the first track and a second internal region aligned with the second track.
Each at least one set of sensing elements corresponding to each nominal spatial phase comprises features A2 and B2, each extending in the measurement axis direction across the first and second internal region portions, respectively. The detection comprising a conductive loop defining the first and second detection element effective region portions corresponding to the portions of the detection element that are aligned or overlap with the first and second internal region portions. A claim comprising an element, wherein the contribution of the detection signal generated in each conductive loop is a combination of the contributions of the respective detection signals from the first and second detection element effective region portions. Item 1. The electromagnetic induction type encoder according to Item 1. The scale pattern is a signal modulation element or a signal modulation element portion periodically arranged on the first track according to the wavelength W1, and a signal periodically arranged on the second track according to the wavelength W1. It is composed of a modulation element or a signal modulation element portion, and the periodic arrangement of the first track and the second track is offset by (W1) / 2 relative to each other.
The magnetic field generation coil is configured to generate a magnetic flux change of the first polarity in the first internal region portion and to generate a magnetic flux change of the opposite second polarity in the second internal region portion. The electromagnetic induction encoder according to claim 14. Each of the plurality of respective detector element sets corresponding to the plurality of respective spatial phases comprises features A2 and B2, respectively, and the electromagnetic induction encoder thereby between the detector and the scale pattern. Multiple spatially filtered that can be used to reduce or suppress potentially unwanted K-th order spatial harmonic detection signal components that can contribute to the determined relative position error. The electromagnetic induction type encoder according to claim 1, wherein the electromagnetic induction type encoder is configured to provide a detection signal. Each of the plurality of respective detection element sets has a region center of gravity of the entire detection element effective region located within the range along the measurement axis.
The electromagnetic induction encoder according to claim 16, wherein each of the plurality of detection element sets is configured such that the center of gravity of each of the regions is located at the same position along the measurement axis direction. Each positive or negative loop contained in any one of the plurality of respective detection element sets is each other positive or negative loop contained in the same one of the plurality of respective detection element sets. The electromagnetic induction type encoder according to claim 1, wherein each of the detection element effective regions EffASEN that does not overlap with the detection element effective region EffASEN is provided. Each of the detection elements included in each of the plurality of detection element sets has a total detection element effective region EffASEN that is aligned with the internal region or overlaps with one or more of the internal regions, and has a measurement axial direction. At least one of the detection elements defined to have an effective y-axis dimension EffYSEN along the y-axis direction, which is the sum of the dimensions of one or more of the internal regions perpendicular to, and included in each of the plurality of detection element sets. More than half is configured so that the average dimension DSENavg = (EffASEN / EffYSEN) of the detection element along the measurement axis direction is within the range of 0.33 * W1 ± 15%, whereby the electromagnetic induction type encoder is configured. Potentially unwanted third-order spatial harmonic detection signal components and potentially unwanted thirds that may contribute to a determined relative positional error between the detector and the scale pattern. 18. The electromagnetic field according to claim 18, characterized in that it is configured to provide a plurality of spatially filtered detection signals that can be used to reduce or suppress K-order spatial harmonic detection signal components. Inductive encoder.

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