CN109959398B - Winding and scale configuration for an inductive position encoder - Google Patents

Abstract

A pitch-compensated inductive position encoder includes a scale including a first track and a second track having a periodic pattern with a wavelength W, a detector, and a signal processing section. The second track pattern may be shifted in the measurement direction with respect to the first track pattern by a pattern shift amount STO. In the detector, the first and second orbit field-generating coil portions generate fields in first and second inner regions aligned with the first and second pattern tracks, respectively. The first and second sensing coil configurations, which are aligned with the first and second tracks, respectively, are offset in the measurement direction by STO +/-0.5W relative to each other. In various embodiments, the first and second sensing coil configurations may have the same order of individual coil polarities if the generated field polarities are different, and may have an inverted or opposite order if the generated field polarities are the same.

Description

Winding and scale configuration for an inductive position encoder

Cross Reference to Related Applications

This application is a partial continuation of U.S. patent application No.15/850,457, entitled "WINDING AND SCALE CONFIGURATION FOR use in creating a POSITION entry engine", filed 21/12/2017, filed 24/2016, filed 15/245,560, filed 24/WINDING CONFIGURATION FOR USE in creating a POSITION entry engine, the disclosure of each of which is incorporated herein by reference in its entirety.

Technical Field

The present invention relates to measuring instruments, and more particularly to inductive position encoders that may be used with precision measuring instruments.

Background

Various encoder configurations may include various types of optical, capacitive, magnetic, inductive, motion, and/or position transducers. These transducers utilize various geometric configurations of transmitters and receivers in the readhead to measure movement between the readhead and the scale. Magnetic and inductive transducers are relatively robust to contamination, but are not perfect.

U.S. patent No.6,011,389 ('389 patent) describes a faradaic position transducer that can be used in high accuracy applications, U.S. patent nos. 5,973,494 (' 494 patent) and 6,002,250 ('250 patent) describe incremental position sensing calipers and linear scales that include signal generation and processing circuitry, and U.S. patent nos. 5,886,519 (' 519 patent), 5,841,274 ('274 patent), and 5,894,678 (' 678 patent) describe absolute position sensing calipers and electronic band gauges that utilize faradaic transducers. U.S. patent No.7,906,958 (' 958 patent) describes an induced current position transducer that can be used in high accuracy applications, wherein a scale having two parallel halves and multiple sets of transmit and receive coils eliminates some signal biasing components that could otherwise produce errors in the induced current position transducer. However, the' 958 patent requires a non-conventional scale and shows only a schematic coil layout. Thus, the teachings herein, while useful, relate to generating a signal by an "ideal" sensor or at least an "identical" sensor. Rather, it does not account for and/or address certain manufacturing issues and/or limitations, which often result in "non-ideal" sensors resulting from practical layout, manufacturing, and cost constraints. These problems and associated design factors are discussed in detail below.

All of the previously listed U.S. patents are hereby incorporated by reference in their entirety. As described in these patents, inductive current transducers can be manufactured using printed circuit board technology and are largely unconcerned.

However, existing systems are limited in their ability to provide some combination of user-desired features, such as a combination of compact size, signal strength, high resolution, cost, practical layout, and robustness to misalignment and contamination. It would be desirable to provide an improved combined encoder configuration.

Disclosure of Invention

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key 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 electronic position encoder is provided that can be used to measure the relative position between two elements along a measurement axis direction that coincides with the x-axis direction. In various embodiments, an electronic position encoder includes a scale and a detector portion. In various embodiments, a signal processing arrangement may be operatively connected to the detector portion to provide a drive signal (e.g., to the field generating coil configuration) and determine a relative position between the detector portion (e.g., the sensing coil configuration) and the scale pattern based on the detector signal input from the detector portion. In various embodiments, the signal processing arrangement may be integrated with the detector portion (e.g., as circuitry on a circuit board that serves as a substrate for the detector portion). In other embodiments, the signal processing arrangement may comprise an external circuit connected to the detector portion by a connector.

The scale extends in a measurement axis direction and includes a signal modulating scale pattern including first and second pattern tracks arranged parallel to each other. Each pattern track includes field attenuating elements that locally attenuate a varying magnetic flux to a relatively large extent; and field sustaining elements that locally attenuate the varying magnetic flux to a relatively small extent or locally enhance the varying magnetic flux. The field attenuating elements and the field sustaining elements are interleaved in a periodic pattern having a spatial wavelength W along the x-axis direction.

The detector portion is configured to be mounted adjacent to the pattern track and to move relative to the pattern track in the direction of the measurement axis. In various embodiments, the detector portion includes a field generating coil configuration and a sensing coil configuration.

The field generating coil configuration comprises at least one field generating loop, which may be fixed on the substrate. The field generating coil configuration is configured to respond to a varying first magnetic flux provided by the coil drive signal in a first interior region aligned with the first pattern track and to respond to a varying second magnetic flux provided by the coil drive signal in a second interior region aligned with the second pattern track.

The sensing coil configuration includes a first track first spatial phase signal sensing coil configuration, and a second track first spatial phase signal sensing coil configuration. In various embodiments, the sensing coil configuration may further include first and second track "additional" phase signal coil configurations (e.g., second, third, fourth spatial phase signal coil configurations, etc.) similar to the first spatial phase signal coil configurations of the first and second tracks, according to known principles, and depending on the desired signal processing and position measurement techniques to be used in conjunction with the detector portion.

A first track first spatial phase signal sensing coil configuration is arranged in the first interior region and includes a set of N positive windings distributed in a positive winding region that repeats in the x-axis direction corresponding to the spatial wavelength W, and a set of N negative windings distributed in a negative winding region that alternates with the positive winding region and repeats in the x-axis direction corresponding to the spatial wavelength W. N is an integer of at least 2. The positive and negative pole windings each respond to a local effect on the varying magnetic flux provided by an adjacent field attenuating element or field maintaining element and provide a signal contribution to a first track first spatial phase signal component provided by a first track first spatial phase signal sensing coil configuration. A second track first spatial phase signal sensing coil configuration is arranged in the second interior region and includes a set of M positive windings distributed in a positive winding region that repeats in the x-axis direction corresponding to the spatial wavelength W, and a set of M negative windings distributed in a negative winding region that alternates with the positive winding region and repeats in the x-axis direction corresponding to the spatial wavelength W. M is an integer of at least 2. The positive and negative pole windings each respond to a local effect on the varying magnetic flux provided by an adjacent field attenuating or field maintaining element and provide a signal contribution to a second track first spatial phase signal component provided by a second track first spatial phase signal sensing coil configuration.

Unlike prior art configurations (e.g., as in the' 958 patent), the first track first spatial-phase signal sensing coil configuration and the second track first spatial-phase signal sensing coil configuration define first and second sensing spans, respectively, along the x-axis direction, and the first and second sensing spans are not aligned with each other along the x-axis direction, and the first track first spatial-phase signal sensing coil configuration and the second track first spatial-phase signal sensing coil configuration are not symmetric with each other about a boundary line between the first and second pattern tracks along the x-axis. This provides a certain degree of practical design freedom and other advantages described in detail below.

Unlike prior art configurations (e.g., as in the' 958 patent), in various embodiments, the periodic pattern of the second pattern track is aligned or offset in the x-axis direction relative to the periodic pattern of the first pattern track by a scale track pattern offset amount STO that is not 0.5W (where W is the scale pattern wavelength or pitch).

In embodiments, the electronic position encoder is configured according to one of a) or B), wherein:

A) the field generating coil configuration is configured to provide varying magnetic fluxes of opposite polarity in a first inner region along the first pattern track and in a second inner region along the second pattern track; and

starting from the start end along the sense coil configuration, the first track first spatial-phase-signal sense coil configuration has a configuration in which its start end winding along the first track has a first winding polarity, the second track first spatial-phase-signal sense coil configuration has a configuration in which its start end winding along the second track has a first winding polarity, and the start end windings along the first and second tracks are offset from each other in the x-axis direction by a winding offset WO STO +/-0.5W.

Or:

B) the field generating coil configuration is configured to provide a varying magnetic flux of the same polarity in a first inner region along the first pattern track and in a second inner region along the second pattern track; and

starting from the start end along the sense coil configuration, the first track first spatial-phase-signal sense coil configuration has a configuration in which its start end winding along the first pattern track has a first winding polarity, the second track first spatial-phase-signal sense coil configuration has a configuration in which its start end winding along the second pattern track has a second winding polarity opposite to the first winding polarity, and the start end windings along the first and second tracks are offset from each other in the x-axis direction by a winding offset WO STO +/-0.5W.

In embodiments according to either a) or B), N may be equal to M. In embodiments according to either A) or B), the scale pattern offset STO may be in the range 0 +/-0.25W. In some embodiments according to either A) or B), the scale pattern offset STO may be zero, which corresponds to the configuration of a conventional scale. In embodiments according to either a) or B), the windings of the first and second track first spatial phase signal sensing coils comprise conductors fabricated in printed circuit board layers, wherein the conductors comprise leads connected between different layers of the printed circuit board and no leads are contained in portions of the windings located in the first and second inner regions.

In embodiments according to either a) or B), the first track first spatial phase signal component and the second track first spatial phase signal component are combined to form a combined first spatial phase signal. In some such embodiments, the respective windings of the first and second track first spatial-phase signal sensing coil configurations comprise respective portions of a continuous conductor in which the first and second track first spatial-phase signal components inherently combine to form a combined first spatial-phase signal. In other such embodiments, as outlined before, the signal processing arrangement may be operatively connected to the detector section, with the first track first spatial phase signal component and the second track first spatial phase signal component connected to inputs of the signal processing circuitry and combined by signal processing to form a combined first spatial phase signal.

In embodiments according to a), starting from the start end along the sensing coil configuration, the first track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the first track has a first winding polarity and its end winding has a second winding polarity opposite to the first winding polarity. In such a case, the second track first spatial phase signal sensing coil configuration has a configuration in which its starting end winding along the second track has a first winding polarity and its ending end winding has a second winding polarity opposite to the first winding polarity.

In various other embodiments according to a), starting from the start end along the sensing coil configuration, the first track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the first track has a first winding polarity and its end winding also has a first winding polarity, at least one winding region between its start end winding and its end winding comprising two windings having a second winding polarity opposite to the first winding polarity. In such a case, the second track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the second track has a first winding polarity and its end winding also has a first winding polarity, at least one winding region between its start end winding and its end winding comprising two windings having a second winding polarity opposite to the first winding polarity.

In embodiments according to B), starting from the start end along the sensing coil configuration, the first track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the first track has a first winding polarity and its end winding has a second winding polarity opposite to the first winding polarity. In such a case, the second track first spatial phase signal sensing coil configuration has a configuration in which its starting end winding along the second track has a second winding polarity opposite to the first winding polarity and its ending end winding has the first winding polarity.

In various other embodiments according to B), starting from the start end along the sensing coil configuration, the first track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the first track has a first winding polarity and its end winding also has a first winding polarity, at least one winding region between its start end winding and its end winding comprising two windings having a second winding polarity opposite to the first winding polarity. In such a case, the second track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the second track has a second winding polarity opposite to the first winding polarity and its end winding also has a second winding polarity opposite to the first winding polarity, at least one winding region between its start end winding and its end winding including two windings having the first winding polarity.

The most basic combination of design features disclosed above is sufficient to eliminate certain design constraints in the prior art (e.g., in the' 958 patent), which have been deemed necessary design constraints of course to compensate or cancel certain "offset" signal components in an inductive encoder. As an example, the' 958 patent requires that there be no widely available non-conventional scale (i.e., a scale having two parallel tracks in which the scale pattern is offset relative to each other by one-half of its scale pitch). Such scales have cost and availability drawbacks and are not compatible with other types of detectors. Advantageously, non-conventional or conventional scales may be used with the respective embodiments disclosed herein. As another example, the prior art (' 958 patent) assumes or requires perfect symmetry in two symmetric halves of a detector section aligned along two parallel scale tracks. However, this does not take into account that placement and routing asymmetries may arise due to actual placement, manufacturing, or manufacturing constraints, which would result in various signal asymmetries and prevent "signal skew" from being obtained. This is particularly true considering that multiple "spatial phase" coil configurations must overlap in the same region (as opposed to the simple "single phase" schematic representation shown in the' 958 patent). This is also particularly true for relatively long detector designs, which may require many sensing loops with small dimensions in order to obtain high resolution and sufficient signal levels. Advantageously, the detector portion design principles disclosed herein allow for a greater number of actual layout and manufacturing alternatives, and potential signal asymmetries that could otherwise arise due to actual layout and manufacturing constraints can be reduced to an insignificant degree in accordance with the layout principles and features disclosed herein.

Advantageously, the design principles and features disclosed herein also provide an alternative for overcoming position measurement errors resulting from "dynamic pitch" effects explained in U.S. Pat. Nos. 5,998,990 and 7,239,130 (the '990 and' 130 patents, respectively), each of which is incorporated herein by reference in its entirety. The design principles and features disclosed herein may be used alone or in combination with the solutions disclosed in, for example, the '990 and/or' 130 patents to reduce and/or cancel errors resulting from "dynamic pitch" effects while using conventional scale and/or lower cost detector portion design configurations, even for pitch and/or high resolution position encoders.

Drawings

FIG. 1 is an exploded isometric view of a hand tool type caliper utilizing an electronic position encoder including a detector portion and a scale.

FIG. 2 is a plan view illustrating a first exemplary embodiment of a detector portion that may be used in an electronic position encoder.

FIG. 3 is a plan view illustrating a second exemplary embodiment of a detector portion that may be used in an electronic position encoder.

Fig. 4 is an isometric view illustrating a first exemplary embodiment of an end portion of a field generating coil of a detector section.

Fig. 5 is an isometric view illustrating a second exemplary embodiment of an end portion of a field generating coil of a detector section.

FIG. 6 is a block diagram of one exemplary embodiment of components of a measurement system including an electronic position encoder.

FIG. 7 is a plan view showing a third exemplary embodiment of a detector portion and a compatible scale pattern that may be used in an electronic position encoder.

FIG. 8 is a plan view showing a fourth exemplary embodiment of a detector portion and a compatible scale pattern that may be used in an electronic position encoder.

FIG. 9 is a plan view showing a fifth exemplary embodiment of a detector portion and a compatible scale pattern that may be used in an electronic position encoder.

FIG. 10 is a plan view showing a sixth exemplary embodiment of a detector portion and a compatible scale pattern that may be used in an electronic position encoder.

FIG. 11 is a plan view showing a seventh exemplary embodiment of a detector portion and a compatible scale pattern that may be used in an electronic position encoder.

FIG. 12 is a plan view showing an eighth exemplary embodiment of a detector portion and a compatible scale pattern that may be used in an electronic position encoder.

FIG. 13 is a plan view showing a ninth exemplary embodiment of a detector portion and a compatible scale pattern that may be used in an electronic position encoder.

Detailed Description

Fig. 1 is an exploded isometric view of a handheld tool type caliper 100 including a scale member 102 and a slider assembly 120, the scale member 102 having a generally rectangular cross-section including a scale 170. In various embodiments, the scale 170 may extend in the measurement axis direction MA (e.g., corresponding to the x-axis direction) and may include a signal-modulating scale pattern 180. A known type of cover layer 172 (e.g., 100 μm thick) may cover the scale 170. The jaws 108 and 110 near the first end of the scale member 102 and the movable jaws 116 and 118 on the slider assembly 120 are used in a known manner to measure the size of an object. The slider assembly 120 may optionally include a depth rod 126 that is retained in a depth rod channel 152 below the scale member 102 by an end stop 154. The depth rod engagement end 128 may extend into the bore to measure its depth. The cover 139 of the slider assembly 120 may include an open/close switch 134, a zero setting switch 136, and a measurement display 138. The base 140 of the slider assembly 120 includes a leading edge 142 that contacts a side edge 146 of the scale member 102, and a screw 147 biases a resilient pressure bar 148 against a mating edge of the scale member 102 to ensure proper alignment, for measurement, and for moving the readhead portion 164 relative to the scale 170.

A pick-up assembly 160 mounted on the base 140 holds a readhead portion 164, which in this embodiment comprises a substrate 162 (e.g. a printed circuit board) carrying a detector portion 167 and a signal processing arrangement 166 (e.g. control circuitry), the detector portion 167 comprising a field generating coil and a set of sensing elements (e.g. together referred to as a field generating and sensing winding configuration) arranged along the measurement axis direction MA. The elastomeric seal 163 may be compressed between the cover 139 and the substrate 162 to isolate contaminants from the circuitry and connections. The detector portion 167 may be covered with an insulating coating.

In one particular illustrative example, the detector portion 167 may be arranged parallel to the scale 170 and facing the scale 170, and a front face of the detector portion 167 facing the scale 170 may be separated from the scale 170 (and/or the scale pattern 180) by a gap on the order of 0.5mm in the depth (Z) direction. The readhead portion 164 and scale 170 may together form a transducer that is part of an electronic position encoder. In one embodiment, the transducer may be an eddy current transducer that operates by generating a varying magnetic field that induces circulating currents (which are also referred to as eddy currents) in some of the signal modulating elements of the scale pattern 180 within which the scale pattern 180 is disposed, as will be described in more detail below. It will be appreciated that the caliper 100 as shown in fig. 1 is typical of various applications implementing electronic position encoders that have been developed over the years to provide a relatively optimized combination of compact size, low power operation (e.g., for long battery life), high resolution and high measurement accuracy, low cost and pollution robustness. In any of these factors, even small improvements are highly desirable but difficult to achieve, particularly in view of the design constraints imposed in each application to achieve commercial success. The principles disclosed in the following description provide improvements in these factors in a particularly cost-effective and compact manner.

FIG. 2 is a plan view of a first exemplary embodiment of a detector section 167 and a signal-modulating scale pattern 180, etc., that may be used in the electronic position encoder shown in FIG. 1. Fig. 2 may be considered partially representative and partially schematic. The detector section 167 and an enlarged portion of the scale pattern 180 are shown in the lower part of fig. 2. In fig. 2, the various elements described below are represented by their shapes or contours and are shown superimposed on each other to emphasize some geometrical relationships. It is to be understood that the various elements may be in different fabrication layers located at different planes along the z-axis direction, such as providing various operational gaps and/or insulating layers as desired, as will be apparent to one of ordinary skill in the art based on the description and/or overview below with reference to fig. 4. Throughout the drawings of the present specification, it will be appreciated that the x-axis, y-axis, and/or z-axis dimensions of one or more elements may be exaggerated for clarity.

The illustrated portion of the scale pattern 180 includes signal modulating elements SME, shown in dashed outline, that are positioned on the scale 170 (shown in fig. 1). In the embodiment shown in fig. 2, the y-direction edges of most of the signal-modulating elements SME are hidden below the first and second elongated portions EP1 and EP 2. It will be appreciated that the scale pattern 180 moves relative to the detector section 167 during operation, as shown in fig. 1.

In the example of fig. 2, the scale pattern 180 has a nominal scale pattern width dimension NSPWD in a y-axis direction perpendicular to the x-axis and includes discrete signal modulating elements SME that are periodically arranged in a measurement axis direction MA (e.g., corresponding to the x-axis direction). More generally, however, the scale pattern 180 may comprise a variety of spatially alternating molded patterns comprising discrete elements or one or more continuous pattern elements, so long as the pattern has spatial characteristics that vary in accordance with position along the x-axis direction to provide a position-dependent detector signal (also referred to as a detector signal component, in some embodiments) generated in a sensing element SEN (e.g., SEN14) of the detector portion 167 according to known methods.

In various embodiments, the detector section 167 is configured to be mounted adjacent to the scale pattern 180 and to move relative to the scale pattern 180 along the measurement axis direction MA. The detector section includes a field generating coil FGC and a plurality of sensing elements, which may have various alternative configurations for use in combination with various corresponding signal processing mechanisms in various embodiments, as will be understood by those skilled in the art. FIG. 2 shows a representative single set of sense elements SEN1-SEN24, which in this particular embodiment include series-connected sense loop elements (alternatively referred to as sense coil elements or sense winding elements). In this embodiment, adjacent ring elements are connected by conductor formations on the respective PCB layers, which are connected by leads according to known methods (e.g. as shown in fig. 4) such that they have opposite winding polarities. That is, if a first loop responds to a changing magnetic field with a positive polarity detector signal contribution, then an adjacent loop responds with a negative polarity detector signal contribution. In this particular embodiment, the sensing elements are connected in series such that their detector signals or signal contributions are summed, the "summed" detector signals being output to a signal processing arrangement (not shown) at detector signal output connections SDS1 and SDS 2. Although fig. 2 shows a single set of sensing elements to avoid visual confusion, it will be appreciated that in some embodiments it may be advantageous to configure the detector to provide one or more additional sets of sensing elements at different spatial phase positions (e.g., to provide quadrature signals), as will be appreciated by those skilled in the art. It will be appreciated that the configuration of the sensing elements described herein is merely exemplary and not limiting. As an example, in some embodiments, each sense element loop may output a separate signal to a corresponding signal processing configuration, for example as disclosed in co-assigned pending U.S. patent application No.15/199,723, filed 2016, 6, 30, which is incorporated herein by reference in its entirety. More generally, in various embodiments, various known sensing element configurations may be used in combination with the principles disclosed and claimed herein for combination with various known scale patterns and signal processing mechanisms.

Each of the sensing elements and the field generating coil FGC may be fixed on a substrate (e.g., the substrate 162 of fig. 1). The field generating coil FGC may be described as surrounding an inner region INTA having a nominal coil region length dimension NCALD in the x-axis direction and a nominal coil region width dimension of substantially YSEP in the y-axis direction. In various embodiments, the field generating coil FGC may comprise a single turn around the inner region INTA. In operation, the field generating coil FGC produces a varying magnetic flux in the inner region INTA in response to a coil drive signal.

In various embodiments, the field generating coil FGC may comprise an input portion INP, first and second elongated portions EP1 and EP2, and an end portion EDP (e.g., in accordance with the implementations disclosed with reference to fig. 4 and/or 5). The input section INP comprises first and second connection sections CP1 and CP2, which connect coil drive signals from a signal processing arrangement (e.g., signal processing arrangement 166 of fig. 1, signal processing arrangement 766 of fig. 6, etc.) to the field generating coils FGC. In some embodiments, the first and second connection portions CP1 and CP2 may be connected to the signal processing arrangement by printed circuit board leads or the like, and the connections may be further shielded using those principles disclosed below with reference to the end portion EDP. The first and second elongated portions EP1 and EP2 each extend adjacent a side of the interior region INTA in the x-axis direction and have a nominal resulting trace width dimension NGTWD in the y-axis direction. In the illustrated embodiment, the nominal generated trace width dimension NGTWD is the same for EP1 and EP2, but this is not a requirement in all embodiments. The end portions EDP (for example, as implemented as disclosed with reference to fig. 4 and/or 5) are spaced apart across the y-axis direction corresponding to the nominal coil width dimension YSEP between the first and second elongate portions EP1 and EP2 to provide a connection therebetween proximate the ends of the inner region INTA. In embodiments according to the principles disclosed herein, the field generating coils FGC are advantageously constructed with a design ratio wherein each nominal generating trace width dimension NGTWD is at least 0.1 times the nominal coil region width dimension YSEP. In some embodiments, the field generating coils FGC may be configured such that each nominal generated trace width dimension NGTWD is at least 0.15 times, or at least 0.25 times, or at least 0.5 times the nominal coil region width dimension YSEP. In some embodiments, the field generating coils FGC may be configured such that each nominal generated trace width dimension NGTWD is at least 25 times the skin depth of the elongated portions EP1 and EP2 at a nominal operating frequency defined corresponding to the detector signal produced in response to the varying magnetic flux.

The sensing elements SEN1-SEN24 are arranged along the x-axis direction (e.g., corresponding to the measurement axis direction MA) and are fixed on a substrate (e.g., substrate 162 of FIG. 1). In the example of FIG. 2, each sense element SEN has a nominal sense element width dimension NSEWD in the y-axis direction, where at least a majority of the nominal sense element width dimension NSEWD is contained within a nominal coil region width dimension YSEP in the y-axis direction. The sensing element SEN is configured to provide a detector signal that is responsive to a local effect on the changing magnetic flux provided by the modulated portions of the scale pattern 180 of the adjacent scale 170. The signal processing arrangement (e.g., signal processing arrangement 166 of fig. 1, or signal processing arrangement 766 of fig. 6, etc.) may be configured to determine the position of the plurality of sensing elements SEN1-SEN24 relative to scale 170 based on the detector signals output from detector portion 167. In general, the field generating coils FGC and the sensing elements SEN1-SEN24, etc. may operate in accordance with known principles (e.g., those used in inductive encoders), such as those described in the incorporated references.

In embodiments, the field generating coil FGC and the sensing element SEN are insulated from each other (e.g., as being located in different layers of a printed circuit board, etc.). In one such embodiment, the nominal sensing element width dimension NSEWD of at least one sensing element SEN is advantageously greater than the nominal coil region width dimension YSEP and extends beyond the inner edge IE of at least one elongated portion EP1 or EP2 by an amount defined as the overlap dimension OD. Additionally, in various embodiments, the field generating coil FGC may advantageously be configured such that the nominal generated trace width dimension NGTWD is greater than the corresponding overlap dimension OD. In various embodiments, the elongated portions EP1 and EP2 may be fabricated on a first layer of the printed circuit board, and the sensing element SEN may comprise a conductive loop fabricated in one or more layers of the printed circuit board, the one or more layers comprising a layer different from the first layer, at least in the vicinity of the overlap dimension OD.

In various embodiments, the substrate may comprise a printed circuit board and the field generating coil FGC may comprise conductive traces fabricated on the printed circuit board (e.g., including elongated portions EP1 and EP 2). In various embodiments, the sensing element SEN may comprise a magnetic flux sensing loop formed from conductive traces fabricated on a printed circuit board. As described above with respect to fig. 1, in various embodiments, detector portion 167 may be included in various types of measurement instruments (e.g., calipers, micrometers, gauges, linear scales). For example, the detector section 167 may be fixed to a sliding member, and the scale pattern 180 may be fixed to a beam member having a measurement axis that coincides with the x-axis direction. In such a configuration, the slide member may be movably mounted on the beam member and may move in a plane along the x-axis direction and the y-axis direction along the measurement axis direction MA, the z-axis direction being orthogonal to the plane.

FIG. 3 is a plan view of a second exemplary embodiment of a detector section 367 or the like that may be used as the detector section 167 in the electronic position encoder shown in FIG. 1. Detector portion 367 has similar characteristics and components as detector portion 167 of FIG. 2, and its design and operation are configured to carry out the design principles disclosed and claimed herein. In particular, elements designated by "primed" reference numerals in FIG. 3 are similar to elements having corresponding similar "unprimed" reference numerals of FIG. 2 and may be understood to operate similarly unless otherwise noted below.

The primary difference between the embodiments of fig. 3 and fig. 2 is that detector section 367 is narrower in the y-axis direction than detector section 167, so that nominal scale pattern width dimension NSPWD is significantly larger than nominal scale pattern width dimension NSPWD' and the significantly other y-axis dimension of detector section 367. For example, in one particular embodiment, the nominal scale pattern width dimension NSPWD' may be about 2/3 or less of the nominal scale pattern width dimension NSPWD. In various embodiments, such a configuration may result in greater lateral offset tolerance for lateral movement of detector portion 367 relative to scale pattern 180.

Although this distinction exists, other features of detector portion 367 may be similar to those of detector portion 167. For example, each sense element SEN 'may have a nominal sense element width dimension NSEWD' in the y-axis direction, where at least a majority of the nominal sense element width dimension NSEWD 'is contained within a nominal coil region width dimension YSEP' in the y-axis direction. In various embodiments, the field generating coil FGC 'includes first and second elongated portions EP 1' and EP2 'and an end portion EDP' (e.g., in accordance with the implementations disclosed with reference to fig. 4 and/or 5), all of which may have similar configurations as the corresponding elements of the detector portion 167. In some embodiments, the field generating coils FGC ' may be configured such that each nominal generated trace width dimension NGTWD ' is at least 0.1 times, or at least 0.15 times, or at least 0.25 times, or at least 0.50 times the nominal coil region width dimension YSEP '. Other features and/or design relationships may also be similar to those described with reference to fig. 2, if desired.

With respect to the example configuration of detector portions 167 and 367 above, it should be appreciated that some prior systems utilized relatively narrow traces and/or relatively large internal regions (e.g., a large region INTA and/or a nominal coil region width dimension YSEP) for the field generating coils. More particularly, in some prior systems it is generally desirable that the associated detector section elements have a relatively high inductance, so that the system will have a sufficiently high Q to resonate for a relatively long time, which is considered advantageous for the signal processing and measurement methods utilized. In contrast, according to the principles disclosed herein, utilizing a wider trace width (e.g., at the expense of INTA and/or YSEP, for the total detector y-axis dimension limit imposed by a particular application) results in a relatively smaller inductance and smaller total impedance, for which a larger amount of current can flow in a relatively shorter time (e.g., producing a stronger signal) and resonance can still be obtained for a desired length of time for measurement. As described above with respect to detector portions 167 and 367, in various embodiments, each nominal generated trace width dimension NGTWD is at least 0.10 times, or at least 0.15 times, or at least 0.25 times, or at least 0.50 times the nominal coil region width dimension YSEP. As some specific example values, in some embodiments, the nominal coil region width dimension YSEP may be on the order of 2.0mm or 8.0mm or 10mm, and each nominal resulting trace width dimension NGTWD may be on the order of at least 0.25mm or 0.50mm or 1.00mm or more. These can be compared to trace widths in some prior systems on the order of 0.10 mm. Configurations such as those disclosed herein have been determined in some instances to achieve detector signal levels that exceed comparable prior art configurations signal levels by a factor of 1.5 or more, and in some cases by a factor of 3 or more, when comparable drive signals are input to the field generating coils.

Relative to the example configurations of detector portions 167 and 367, etc., in some embodiments, sensing elements SEN (e.g., region-enclosing rings or coil elements as shown in fig. 2 and 3) may provide some advantages (e.g., increased gain, etc.) relative to more conventional sensing elements if they are configured in accordance with the maximum signal gain design disclosed herein, wherein the amount of sensing element field-receiving region coincident with or within (e.g., within an INTA) field-generating coil FGC should be relatively maximized, while the amount of sensing element field-receiving region located outside of the conductors forming field-generating coil FGC (e.g., in the y-axis direction) should be relatively maximized. It will be appreciated that the sensing element SEN as shown in FIG. 2 exhibits an overlap dimension OD which has the above-described design relationship consistent with this principle. For example, each nominal generated trace width dimension NGTWD is made larger than the corresponding overlap dimension OD.

Fig. 4 is an isometric "wireframe" view illustrating a first exemplary embodiment of an end portion EDP of a field generating coil FGC included in a detector portion 467, according to principles disclosed and claimed herein. It should be appreciated that the elements of detector portion 467 may have been designed and operated similarly to like numbered elements of detector portion 167 of fig. 2. The detector section 467 includes field generating coils FGC and a plurality of sensing elements SEN1-SEN24 (illustrative sensing elements SEN17-SEN24 are shown in FIG. 4). The field generating coil FGC comprises first and second elongated portions EP1 and EP2 and an end portion EDP, and is fixed on a base plate (e.g., base plate 162 of fig. 1) and surrounds an inner region INTA.

In various embodiments, the field generating coil FGC and the sensing element SEN are insulated from each other, e.g. they are located in different layers of a printed circuit board (the layer structure is not clearly shown in fig. 4). In fig. 4, the Z coordinate of each mark may be understood to coincide with or identify a corresponding surface of each Printed Circuit Board (PCB) layer, although alternative manufacturing methods may be used. The elements SME of the scale pattern 180 are present on the surface of the scale 170 (as shown in fig. 1) at the Z-coordinate Zsme. It is understood that scale 170 is separate from a Printed Circuit Board (PCB) carrying the elements of detector portion 467. In the embodiment shown in fig. 4, the front surface of the PCB (e.g., the front surface with the insulating coating) is located at Z coordinate Zfs. There is an operating gap between the scale element Z coordinate Zsme and the front surface Z coordinate Zfs. The elongated portions EP1 and EP2 may be manufactured on the surface of a PCB layer having Z coordinates Zep, and they may be covered by an insulating coating. The sensing element SEN may comprise interconnected conductive loop portions located on respective PCB layer surfaces having Z coordinates ZseL1 and ZseL 2. The conductive loop portions may be connected between the layers using wires so that the conductors may be interleaved with each other while connecting the sense signal contributions in series and providing a responsive signal contribution polarity, as previously described.

The first and second elongated portions EP1 and EP2 each extend in the x-axis direction and are nominally located in the z-axis direction perpendicular to the x-axis and y-axis directions at a z-distance EPZD ═ (Zep-Zsme) from the front surface elongated portion of the PCB facing the detector portion 467 of the scale pattern 180. As mentioned above, the end portion EDP includes conductive paths spaced across the y-axis direction corresponding to the nominal coil width dimension YSEP between the first and second elongate portions EP1 and EP2 to provide connections therebetween proximate the ends of the interior region INTA. In the embodiment shown in fig. 4, the end portion EDP comprises a shielding end section SES located on the respective PCB layer surface having a Z coordinate Zses, nominally located at a shielding end section Z distance SESZD ═ (Zses-Zfs) from the front surface of the PCB of the detector portion 467, wherein the shielding end section Z distance SESZD is greater than the elongated portion Z distance EPZD. A first connection portion CNP1 (e.g. a PCB lead) connects the first elongated portion EP1 to a first end of the shielding end section SES, and a second connection portion CNP2 (e.g. a PCB lead) connects the second elongated portion EP2 to a second end of the shielding end section SES.

In the embodiment shown in fig. 4, the detector portion 467 further comprises a conductive shielding region CSR (e.g., a conductive planar region represented by the arbitrarily placed dashed "edge" lines in fig. 4) that extends along the x-axis and y-axis directions and is nominally located on a corresponding PCB layer surface having a Z-coordinate Zcsr, which is nominally located at a shielding region Z-distance SRZD (Zcsr-Zfs) from the front surface of the PCB of the detector portion 467. In various embodiments, the shield region z-distance SRZD is less than the shield end segment z-distance SESZD and the conductive shield region CSR is located between at least a portion of the shield end segment SES and the front surface of the PCB of the detector portion 467. The conductive shielding region CSR may comprise portions of an extended ground plane layer in the PCB of the detector portion 467, or in some embodiments it may comprise discrete regions. The conductive shielding region CSR may include a clearance hole such that the first and second connection portions CNP1 (e.g., PCB leads) are separated or insulated from the conductive shielding region CSR.

In general, previously known configurations for end portions of field generating coils (e.g., end portions extending in the y-axis direction) produce field components that have resulted in erroneous components in the detector signals closest to their sensing elements — known as "end effects". Attempts have been made to eliminate this end effect by utilizing a "tapered end configuration" in the detector and/or by separating the end portion away from the end sensing element. However, these solutions undesirably reduce signal strength, or increase detector x-axis dimension, or both. In contrast, the above-described shielding configuration tends to reduce the field component generated by the end portion and/or prevent it from reaching the signal modulating element SME. In this way, the field component coupled to the nearest sensing element is small and/or substantially constant regardless of the scale position, thereby substantially eliminating any end effects.

As mentioned above, in various embodiments the elongated portions EP1 and EP2 may be manufactured on a first layer of the printed circuit board, the shielding end section SES may be manufactured on a second layer of the printed circuit board, and the electrically conductive shielding region CSR is manufactured on a layer of the circuit board which is closer to a front surface of the detector (e.g. a front surface of a PCB of the detector) than the second layer of the printed circuit board. In one such embodiment, the conductive shield region CSR may be fabricated on a layer of the printed circuit board that is located between the first layer and the second layer. In such a configuration, the conductive shielding region CSR may comprise at least a portion of a ground plane layer of the printed circuit board, wherein the ground plane layer is located between the first layer and the second layer. In one embodiment, the connection between the elongated portion EP1 or EP2 and the shielding end section SES (e.g., as part of the first or second connection portion CNP1 or CNP 2) may comprise printed circuit board leads extending in the z-axis direction. In one such configuration, the conductive shielding region CSR may be fabricated on a layer of the printed circuit board between the first and second layers, and the printed circuit board leads may pass through openings fabricated in the conductive shielding region CSR.

Fig. 5 is an isometric "wireframe" view illustrating a second exemplary embodiment of an end portion EDP of a field generating coil FGC incorporated in a detector section 567, according to principles disclosed and claimed herein. It should be appreciated that the elements of detector portion 567 may be designed and operated similarly to like-numbered elements of detector portion 167 of fig. 2 and/or detector portion 467 of fig. 4, and may be substantially understood by analogy therewith.

In fig. 5, as in fig. 4, the Z coordinate of each mark may be understood to coincide or identify each surface of each Printed Circuit Board (PCB) layer, but alternative manufacturing methods may also be used. The elements SME of the scale pattern 180 are located on the surface of the scale 170 (as shown in fig. 1) at the Z-coordinate Zsme. The detector section 567 has a front surface (e.g., a front surface of an insulating coating on a PCB of the detector section 567) located at a Z coordinate Zfs. There is an operating gap between the scale element Z coordinate Zsme and the front surface Z coordinate Zfs. The elongated portions EP1 and EP2 may be manufactured on the surface of a PCB layer having Z coordinates Zep, and they may be covered by an insulating coating. The sensing element SEN may comprise interconnected conductive loop portions located on respective PCB layer surfaces having Z coordinates ZseL1 and ZseL2, connected as outlined above with reference to the detector portion 467.

The first and second elongated portions EP1 and EP2 are nominally located at a z-distance EPZD (Zep-Zsme) from the elongated portion facing the front surface of the detector portion 567 of the scale pattern 180. As in detector portion 467, the end portion EDP includes conductive paths that are spaced across the y-axis direction corresponding to the nominal coil width dimension YSEP between the first and second elongated portions EP1 and EP2 to provide connections therebetween proximate the ends of the inner region INTA. In the embodiment shown in fig. 5, the end portion EDP "comprises a shielding end section SES" located on the respective PCB layer surface having a Z-coordinate Zses ", nominally located at a shielding end section Z-distance SESZD" ═ (Zses "-Zfs) from the front surface of the detector portion 567, wherein the shielding end section Z-distance SESZD" is greater than the elongated portion Z-distance EPZD. A first connection portion CNP1 (e.g. comprising PCB leads CNP1A and conductive traces CNP1B) connects the first elongated portion EP1 to a first end of the shield end segment SES, and a second connection portion CNP2 (e.g. comprising PCB leads CNP2A and conductive traces CNP2B) connects the second elongated portion EP2 to a second end of the shield end segment SES.

In the embodiment shown in fig. 5, the detector section 567 further comprises a conductive shielding region CSR "(e.g., a conductive planar region indicated by the dashed edge lines in fig. 5) extending in the x-axis and y-axis directions and nominally located on a corresponding PCB layer surface having a Z-coordinate Zcsr", which is nominally located at a shielding region Z-distance SRZD "— (Zcsr" -Zfs) from the front surface of the PCB of the detector section 567. In various embodiments, the shield region z-distance SRZD "is less than the shield end section z-distance SESZD", and the conductive shield region CSR "is located between at least a portion of the shield end section SES" and the front surface of the PCB of the detector portion 567. For the example shown in fig. 5, it should be appreciated that in some embodiments, the shielded region CSR "may be located on the same surface as the elongated portions EP1 and EP2, if desired (i.e., Zcsr" ═ Zep and EPZD ═ SRZD ", if desired). Furthermore, in one such embodiment, the shield end segment SES "and the conductive traces CNP1B and CNP2B may be located on the same surface(s) for the sense element SEN, if desired (i.e., Zses" ═ ZseL1 or Zses "═ ZseL2, if desired). In such embodiments, the PCB of detector portion 567 may include fewer layers and/or be thinner along the z-axis than detector portion 467. In any event, the shielding configuration at the end portion EDP "of the detector portion 567 eliminates the end effect in a manner similar to that previously outlined with reference to the end portion EDP of the detector portion 467.

With regard to the example detector portions 467 and 567 described above, it should be appreciated that the conductive shielding region(s) CSR (CSR ") may reduce the effect (e.g., with respect to varying magnetic flux) of the shielding end segments SES on the sensing element SEN based at least in part on the relative layer positions of the shielding end segments SES (e.g., located on different PCB layers, etc.) relative to the layer positions of the elongated portions EP1 and EP2 of the field generating coil FGC. Such a configuration may allow the use of the conductive shielding region(s) CSR (CSR ") and allow the field generating coil FGC to have a shorter overall x-axis dimension (e.g., to this end, the end portion EDP need not be located away from the sensing element SEN to avoid affecting the detector signal produced in response to the changing magnetic flux, etc.).

FIG. 6 is a block diagram of one exemplary embodiment of components of a measurement system 700 including an electronic position encoder 710. It will be appreciated that some of the numbered components 7XX of fig. 6 may correspond to and/or have similar operation as similarly numbered components 1XX of fig. 1, unless otherwise described below. The electronic position encoder 710 comprises a scale 770 and a detector portion 767, which together form a transducer, and a signal processing arrangement 766. In various embodiments, the detector portion 767 can include any of the configurations described above with respect to fig. 2-6 or other configurations. The measurement system 700 also includes user interface features such as a display 738 and user-operable switches 734 and 736, and may additionally include a power supply 765. In various embodiments, an external data interface 732 may also be included. All of these elements are coupled to a signal processing arrangement 766 (or signal processing and control circuitry), which may be embodied as a single processor. Signal processing arrangement 766 determines the position of the sensing elements of detector portion 767 relative to scale 770 based on the detector signals input from detector portion 767.

In various embodiments, the signal processing arrangement 766 of fig. 6 (and/or the signal processing arrangement 166 of fig. 1) may include or consist of one or more processors running software to perform the functions described herein. A processor includes a programmable general purpose or special purpose microprocessor, a programmable controller, an Application Specific Integrated Circuit (ASIC), a Programmable Logic Device (PLD), or the like, or a combination of such devices. The software may be stored in a memory, such as Random Access Memory (RAM), Read Only Memory (ROM), flash memory, etc., or a combination of such components. The software may also be stored in one or more memory devices, such as an optical disk, a flash memory device, or any other type of non-volatile memory for storing data. Software may include one or more program modules including routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. In a distributed computing environment, the functionality of the program modules may be combined or distributed in a wired or wireless configuration across multiple computing systems or devices, and accessed via a service request.

FIG. 7 is a plan view of a third exemplary embodiment of a detector portion 767 and a compatible scale pattern 780, which may be used as the detector portion 167 and the scale pattern 180, respectively, in the electronic position encoder shown in FIG. 1. Detector portion 767 has similar characteristics and components as detector portion 167 of FIG. 2, and its design and operation are configured to implement the various design principles disclosed and claimed herein. In particular, like elements are indicated by reference numerals or numbers in fig. 7, like or identical to those in fig. 2 or other figures herein (e.g., like "XX" prefixed as 7XX and 2XX), and can be understood to operate similarly unless specifically noted below. Therefore, only the significant differences of the detector portion 767 and the scale pattern 780 will be described below. The detector portion 767 and the compatible scale pattern 780 provide additional advantages over previously described embodiments with respect to signal accuracy and/or signal length that provide greater robustness, as described in greater detail below.

One primary difference between the embodiments of fig. 7 and 2 is that the scale pattern 780 includes a first pattern track FPT and a second pattern track SPT arranged parallel to each other. The first pattern track FPT has a nominal first pattern track width dimension FPTWD in the y-axis direction between a first track inner limit FTIB, which is closest to the other pattern track, and a first track outer limit FTEB, which is furthest from the other pattern track. The second pattern track SPT has a nominal second pattern track width dimension SPTWD in the y-axis direction between a second track inner limit STIB, which is closest to the other pattern track, and a second track outer limit STEB, which is furthest from the other pattern track. Each of the first and second pattern tracks FPT and STP includes a signal modulating element SME arranged to provide a spatially varying characteristic that varies as a periodic function of position along the x-axis direction. In fig. 7, the illustrated signal modulating elements SME with cross-hatched areas can be considered to represent field attenuating elements that locally attenuate varying magnetic flux to a relatively large extent according to known principles (e.g., they can be conductive plates of a circuit board type scale, or raised areas of a metal strip type scale), and the spaces between the cross-hatched signal modulating elements SME can be considered to represent field maintaining elements that locally attenuate varying magnetic flux to a relatively small extent, or locally enhance varying magnetic flux according to known principles (e.g., they can be non-conductive areas of a circuit board type scale, or recessed areas of a metal strip type pattern).

Another major difference is that the detector portion 767 is configured to operate compatibly with the scale pattern 780. The detector part 767 comprises a field generating coil configuration FGC, which may be fixed on the substrate and comprises a first orbital field generating coil part FTFGCP and a second orbital field generating coil part STFGCP. The field generating coil configuration FGC may comprise an input section INP comprising at least two connection sections (e.g. CP1 and CP2) which connect coil drive signals from the signal processing arrangement to the field generating coil configuration FGC. In the field generating coil configuration FGC, the first track field generating coil portion FTFGCP surrounds a first inner region FINTA aligned with the first pattern track FPT and has a nominal first inner region length dimension FIALD in the x-axis direction and a nominal first inner region width dimension YSEP1 in the y-axis direction and produces a varying first magnetic flux in the first inner region FINTA in response to the coil drive signal. Similarly, the second track field generating coil portion STFGCP surrounds a second inner region SINTA aligned with the second pattern track SPT and has a nominal second inner region length dimension SIALD in the x-axis direction and a nominal second inner region width dimension YSEP2 in the y-axis direction, and generates a varying second magnetic flux in the second inner region SINTA in response to the coil drive signal.

The detector portion 767 also includes a plurality of sensing elements SEN (e.g., SEN1, SEN2) arranged along the x-axis direction and fixed on the substrate, each sensing element SEN having a nominal sensing element width dimension NSEWD along the y-axis direction that spans the first and second inner regions FINTA and SINTA, wherein the plurality of sensing elements SEN are configured to provide detector signals responsive to local effects on the varying magnetic flux provided by the signal modulating elements SME of the adjacent scale pattern 780. In various embodiments, the plurality of sensing elements SEN comprise magnetic flux sensing loops and may be formed by conductive traces and leads fabricated on a printed circuit board. In various embodiments (e.g., as shown in fig. 7), a magnetic flux sense loop configured to provide a first sense loop polarity (e.g., that is responsive to a changing magnetic flux of a first polarity to generate a current in a first direction) is interleaved in the x-axis direction with a magnetic flux sense loop configured to provide a second sense loop polarity (e.g., that is responsive to a changing magnetic flux of an opposite polarity to the first polarity to generate a current in the same direction), the second sense loop polarity being opposite polarity to the first sense loop polarity. A signal processing arrangement may be operatively connected to the detector sections to provide coil drive signals and to determine the relative position between the detector sections and the scale pattern based on detector signals input from the illustrated sensing elements SEN of the detector sections 767 (and other not illustrated sensing elements SEN arranged at other spatial phase positions according to known principles) according to known methods.

As shown in fig. 7, the field generating coil configuration FGC and the sensing element SEN are advantageously configured according to the principles disclosed heretofore. The field generating coil configuration FGC may include one or more of the illustrated leads to implement a shielding configuration for one or more of the end portion EDPs. It is understood that the illustrated leads, which are not needed or desired in certain embodiments, may be omitted.

In the embodiment shown in fig. 7, the first rail inner and outer elongated portions FTIEP and FTOEP, respectively, extend adjacent the first inner region FINTA in the x-axis direction. The first rail inner elongate portion FTIEP is located adjacent the first rail inner extent FTIB and the first rail outer elongate portion FTOEP is located adjacent the first rail outer extent FTEB. The first track inner elongate portion FTIEP has a nominal first track inner generation trace width dimension NFTIGTWD in the y-axis direction. The first track outer elongate portion FTOEP has a nominal first track outer generation trace width dimension nftogtw in the y-axis direction. In accordance with the principles disclosed herein, the nominal first track generation trace width dimensions NFTIGTWD and nftogtwwd (which may be the same or may be different from each other) are each at least 0.1 times the nominal first inner zone width dimension YSEP 1. In some embodiments, it may be advantageous for the first track generation trace width dimensions NFTIGTWD and nftogtwwd to be at least 0.15 times, or at least 0.25 times, or at least 0.50 times the nominal first inner zone width dimension YSEP 1.

The second rail inner and outer elongated portions STIEP and stop, respectively, extend adjacent the second inner region SINTA in the x-axis direction. The second rail inner elongate portion STIEP is located adjacent the second rail inner limit STIB and the second rail outer elongate portion stop is located adjacent the second rail outer limit STEB. The second track inner elongate portion STIEP has a nominal second track inner generation track width dimension nstigtd along the y-axis direction. The second track outer elongated portion stop has a nominal second track outer generation trace width dimension nstotwd in the y-axis direction. In accordance with the principles disclosed herein, the nominal second track generation trace width dimensions nstigwd and NSTOGTWD (which may be the same or may be different from each other) are each at least 0.1 times the nominal second inner zone width dimension YSEP 2. In some embodiments, it may be advantageous for the second track generation trace width dimensions nstigwd and NSTOGTWD to be at least 0.15 times, or at least 0.25 times, or at least 0.50 times the nominal second inner region width dimension YSEP 2. Other features and/or design relationships may also be similar to those described with reference to fig. 2, if desired.

In various embodiments, in combination with the features outlined above, at least a majority of the nominal sensing element width dimension NSEWD is comprised between the first track outer elongate portion FTOEP and the second track outer elongate portion stop. In some embodiments, at least a majority of the nominal sensing element width dimension NSEWD is contained between the first and second track inner regions FINTA and SINTA. In various embodiments, the field generating coil configuration FGC and the sensing element SEN are insulated from each other. As shown in fig. 7, the nominal sense element width dimension NSEWD of at least one sense element SEN is greater than the total inner zone width dimension OIAWD spanned between the first and second track outer elongate portions FTOEP and STOEP and extends beyond the inner edge IE of at least one of the first and second track outer elongate portions FTOEP and STOEP by an amount defined as the overlap dimension (e.g., the first and/or second track overlap dimensions FTOD and STOD, respectively). In embodiments, the field generating coil configuration FGC is configured such that each nominal outer generation trace width dimension (NFTOGTWD and NSTOGTWD) is greater than its associated overlap dimension. In various embodiments, all the elongated portions (FTIEP, FTOEP, STIEP, and STOEP) are fabricated in a first layer of the printed circuit board, and the sensing element SEN comprises a conductive loop fabricated in one or more layers of the printed circuit board, the one or more layers comprising a layer that is at least near the overlap dimension and that is different from the first layer.

In the particular embodiment shown in fig. 7, the first and second pattern tracks FPT and SPT may each include the same type of signal-modulating elements SME arranged in the first and second pattern tracks FPT and SPT along the x-axis direction according to the same spatial period or wavelength W. The signal modulating elements SME in the second pattern track SPT are offset in the measuring axis direction (x-axis direction) from the signal modulating elements in the first pattern track by a nominal scale track pattern offset amount STO of about W/2. As indicated by the current arrows in fig. 7, the field generating coil configuration FGC is configured to produce a first track-varying magnetic flux having a first polarity in the first inner region FINTA and a second track-varying magnetic flux having a second polarity, opposite to the first polarity, in the second inner region SINTA.

As previously mentioned, the plurality of sensing elements SEN may comprise magnetic flux sensing loops (alternatively referred to as sensing coils or sensing windings) having alternating sensing loop polarities in the x-axis direction, the magnetic flux sensing loops being formed by conductive traces fabricated on a printed circuit board. In various embodiments, at least a majority of the magnetic flux sensing loop may span the first and second inner regions FINTA and SINTA in the y-axis direction. As shown in fig. 7, for example, a particular sense element SEN14 may be described as including a first rail positive winding (or winding portion) FTSEN14 and a second rail positive winding (or winding portion) STSEN 14. For example, a particular sense element SEN15 may be described as including a first rail negative winding (or winding portion) FTSEN15 and a second rail negative winding (or winding portion) STSEN15, as may other sense elements. A group or cluster of windings (or winding portions) aligned with a first (track) inner region FINTA provides one embodiment of a first track first spatial phase sensing coil configuration FTFSPSCCF. A group or cluster of windings (or winding portions) aligned with a second (track) inner region SINTA provides one embodiment of a second track first spatial phase sensing coil configuration STFSPSCCF. First and second track first spatial-phase sensing coil configurations FTFSPSCCF and STFSPSCCF together form a total sensing coil configuration SCC that is configured such that, in cooperation with scale pattern 780, all signal components generated in each winding or winding portion thereof (e.g., FTSEN and STSEN) have the same spatial phase. That is, in this particular embodiment, each sense element SEN includes a winding or winding portion that provides the same sense loop polarity in the first and second inner regions FINTA and SINTA. Since the polarity of the magnetic flux generated in the first inner region FINTA is opposite to the polarity of the magnetic flux generated in the second inner region SINTA, this interacts with the pattern of signal modulating elements SME of which the first and second track patterns FTP and STP have a scale track pattern offset STO of about W/2 to produce an enhanced signal contribution in each sensing element SEN. It should be understood that additional sensing coil configurations SCC with different spatial phases may be similarly configured and added to the detector portion 767 according to known principles, and all resulting signals (e.g., quadrature signals) may be processed to provide robust position measurements.

FIG. 8 is a plan view of a fourth exemplary embodiment of a detector portion 867 and a compatible scale pattern 780, which may be used as the detector portion 167 and the scale pattern 180, respectively, in the electronic position encoder shown in FIG. 1. The scale pattern 780 shown in fig. 8 may be similar to or identical to the scale pattern shown in fig. 7 and will not be described in detail below, except with respect to its operation with the detector portion 867. The detector portion 867 has similar characteristics and components to the detector portion 767 of fig. 7, and its design and operation is configured to carry out the various design principles disclosed and claimed herein, and provides similar advantages. Similar elements are designated by reference numerals or numbers in fig. 8, similar or identical to those in fig. 7 or in other figures herein (e.g., similar "XX" prefixed with 8XX and 7XX), and may be understood to operate similarly unless specifically noted below. Therefore, only the significant differences of the detector portion 867 and the detector portion 767 will be described below.

Similar to the detector portion 767, the detector portion 867 is configured for compatible operation with the scale pattern 780. The first track field generating coil portion FTFGCP surrounds a first inner region finata aligned with the first pattern track FPT and has a nominal first inner region length dimension FIALD in the x-axis direction and a nominal first inner region width dimension YSEP1 in the y-axis direction and produces a varying first magnetic flux in the first inner region finata in response to the coil drive signal. Similarly, the second track field generating coil portion STFGCP surrounds a second inner region SINTA aligned with the second pattern track SPT, and has a nominal second inner region length dimension SIALD in the x-axis direction and a nominal second inner region width dimension YSEP2 in the y-axis direction, and generates a varying second magnetic flux in the second inner region SINTA in response to the coil drive signal.

One significant difference between detector portion 867 and detector portion 767 is that field generating coil configuration FGC is configured to produce a first track-varying magnetic flux having a first polarity in a first inner region FINTA and a second track-varying magnetic flux having the same polarity as the first polarity in a second inner region SINTA, as indicated by the current arrows in fig. 8. A second significant difference in the plurality of sensing elements SEN (e.g., SEN1, SEN14) is associated therewith, as described below.

Similar to the detector portion 767, in the detector portion 867, the plurality of sensing elements SEN have a nominal sensing element width dimension NSEWD in the y-axis direction that spans the first and second inner regions FINTA and SINTA, the plurality of sensing elements SEN configured to provide detector signals responsive to local effects on the changing magnetic flux provided by adjacent signal modulating elements SME of the scale pattern 780. As previously mentioned, the plurality of sensing elements SEN may comprise magnetic flux sensing loops (alternatively referred to as sensing coils or sensing windings) formed by conductive traces fabricated on a printed circuit board. In various embodiments, at least a majority of the magnetic flux sensing loop may span the first and second inner regions FINTA and SINTA in the y-axis direction. However, unlike detector portion 767, the flux sense loops shown in detector portion 867 each include an intersection or twist of their conductive traces to provide opposite sense loop polarities in the first and second inner regions FINTA and SINTA. In various embodiments, for at least a majority of the magnetic flux sensing loops, the intersections or twists of their conductive traces are located in or above an "inactive" central region between the first and second inner regions, FINTA, and including the first and second track inner elongated portions, FTIEP and STIEP, to avoid generating undesirable signal interference.

As shown in fig. 8, for example, a particular sense element SEN14 may be described as including a first rail positive winding (or winding portion) FTSEN14 and a second rail negative winding (or winding portion) STSEN 14. For example, a particular sense element SEN15 may be described as including a first rail negative winding (or winding portion) FTSEN15 and a second rail positive winding (or winding portion) STSEN15, with other sense elements being similar. A group or cluster of windings (or winding portions) aligned with the first (track) inner region FINTA provides another embodiment of the first track first spatial phase sensing coil configuration FTFSPSCCF. A group or cluster of windings (or winding portions) aligned with the second (track) inner region SINTA provides another embodiment of the second track first spatial phase sensing coil configuration STFSPSCCF. As shown in fig. 8, the flux sensing loop of sensing element SEN is additionally configured to have opposing sense loop polarities staggered in the x-axis direction in each of the first and second track first spatial phase sensing coil configurations FTFSPSCCF and STFSPSCCF (e.g., one exemplary sense loop conductor view and associated current arrows as schematically illustrated in the lower, enlarged view of fig. 8).

First and second track first spatial-phase sensing coil configurations FTFSPSCCF and STFSPSCCF together form a total sensing coil configuration SCC that is configured such that, in cooperation with scale pattern 780, all signal components generated in each winding or winding portion thereof (e.g., FTSEN and STSEN) have the same spatial phase.

That is, according to the above description, since the polarity of the magnetic flux generated in the first inner region FINTA is the same as the polarity of the magnetic flux generated in the second inner region SINTA, this interacts with the signal modulating element SME having a scale track pattern offset STO of about W/2 in the first and second track patterns FTP and STP to produce an enhanced signal contribution in each "twisted" sensing element SEN. A signal processing arrangement may be operatively connected to the detector sections to provide coil drive signals and to determine the relative position between the detector sections and the scale pattern based on detector signals input from the illustrated sensing elements SEN of the detector sections 867 (and from other not illustrated sensing elements SEN arranged at other spatial phase positions according to known principles) according to known methods.

As shown in fig. 8, the field generating coil configuration FGC and the sensing element SEN are advantageously configured according to the principles disclosed heretofore. The field generating coil configuration FGC may include one or more of the illustrated leads to perform a shielding configuration for one or more end portion EDPs. It is understood that the illustrated leads, which are not needed or desired in certain embodiments, may be omitted. In accordance with the principles disclosed herein, the nominal first track generation trace width dimensions NFTIGTWD and nftogtwwd are each at least 0.1 times the nominal first inner zone width dimension YSEP 1. In some embodiments, it may be advantageous for the first track generation trace width dimensions NFTIGTWD and nftogtwwd to be at least 0.15 times, or at least 0.25 times, or at least 0.50 times the nominal first inner zone width dimension YSEP 1. In accordance with the principles disclosed herein, the nominal second track generation trace width dimensions nstagwd and NSTOGTWD are each at least 0.1 times the nominal second inner zone width dimension YSEP 2. In some embodiments, it may be advantageous for the second track generation trace width dimensions nstigwd and NSTOGTWD to be at least 0.15 times, or at least 0.25 times, or at least 0.50 times the nominal second inner region width dimension YSEP 2.

Other features and/or design relationships used in the detector portion 867 can also be similar to compatible features and/or design relationships described with reference to the detector portion 767, if desired.

The dual track scale pattern used in combination with the field generating polarity and sensing element polarity as similarly outlined above with reference to fig. 7 and 8 may help reduce or eliminate certain signal offset components that would otherwise be generated in a single track scale pattern configuration, as disclosed without reference to the detailed manufacturing or layout considerations in the' 958 patent, which was previously incorporated herein by reference. As previously noted herein, prior systems (e.g., those referenced in the' 958 patent) utilize relatively narrow traces and/or relatively large internal regions (e.g., large regions FINTA and/or SINTA and/or nominal coil region width dimensions YSEP1 and/or YSEP2) for the field generating coil configuration. In some prior systems, it is generally considered desirable for the detector sensing element to have a relatively large area coupled to receive the changing magnetic flux in the inner region of the generating coil, which is considered advantageous for current and signal strength. In contrast, in accordance with the principles disclosed herein, utilizing a wider trace width (e.g., at the expense of the inner regions FINTA and/or SINTA and/or YSEP1 and/or YSEP2 for the total detector y-axis dimension limit imposed by a particular application) results in a relatively smaller total impedance for the field generating coil configuration FGC, for which a larger amount of current can flow in a relatively shorter time (e.g., producing a stronger signal), and resonance of a desired length of time can still be obtained for measurement. This is particularly valuable with respect to dual track scale patterns, which may be limited by practical considerations (e.g., to fit into the same space as previously utilized single track encoders) to relatively small first and second track pattern widths. A dual rail configuration constructed in accordance with the principles disclosed herein has been determined in some instances to achieve detector signal levels that exceed comparable prior art configuration signal levels by a factor of 1.5 or more, and in some cases by a factor of 3 or more, when comparable drive signals are input to the field generating coils.

Although a preferred embodiment has been shown and described with reference to fig. 1-8, numerous variations in the illustrated and described arrangements of features and sequences of operations will be apparent to those skilled in the art based on this description. Various modifications may be made to implement the principles disclosed above.

As an example, the embodiments shown and described with reference to fig. 2 and 3 and fig. 7 and 8 utilize a non-zero overlap dimension OD, but this is not necessary in all embodiments. As another example, the particular configuration of the sense element SEN and scale track pattern offset STO shown in FIGS. 7 and 8 is exemplary only, and not limiting. Other scale track pattern offsets STO may be used in combination with appropriate adaptive changes in the shape of the sensing element SEN to accommodate a particular amount of scale track offset, as will be appreciated by those skilled in the art based on the above description and principles.

FIG. 9 is a plan view illustrating a fifth exemplary embodiment of a detector portion 967 and a compatible scale pattern 980 that may be used in an electronic position encoder. Detector portion 967 has similar characteristics and components as detector portion 767 of FIG. 7, and its design and operation are configured to embody the various design principles disclosed and claimed herein. In particular, similar elements are designated by reference numerals or numbers in fig. 9, similar or identical to those in fig. 7 or in other figures herein (e.g., similar "XX" prefixed as 9XX and 2XX), and may be understood to operate similarly unless specifically noted below. Accordingly, only the significant differences between the detector portion 967 and the scale pattern 980 will be described below. The detector 967 and compatible scale pattern 980 provide certain advantages with respect to providing additional layout and manufacturing options and reduced cost for the detector portion 967 and, in some embodiments, the ability to utilize readily available conventional scales. Additionally, as described in greater detail below, the disclosed design principles and features also provide an alternative for overcoming position measurement errors that result from "dynamic spacing" due to certain mounting tilt or mounting misalignment, as explained in the previously incorporated '990 and' 130 patents.

Similar to the scale pattern 780, the scale pattern 980 includes first and second pattern tracks FPT and SPT disposed in parallel with each other, each pattern track including a signal modulation element SME, which may include a field attenuation element that locally attenuates a varying magnetic flux to a relatively large extent, and a field sustaining element that locally attenuates a varying magnetic flux to a relatively small extent or locally enhances a varying magnetic flux. The signal modulating elements SME (field attenuating elements) and the field sustaining elements are interleaved in a periodic pattern having a spatial wavelength W along the x-axis direction. However, one major difference is that, unlike the scale pattern 780, in the scale pattern 980, the second pattern track SPT is not offset relative to the first pattern track by a scale track pattern offset amount STO of about or exactly W/2. Rather, in the scale pattern 980, the periodic pattern of the second pattern track is aligned or offset in the x-axis direction relative to the periodic pattern of the first pattern track by a scale track pattern offset amount STO that is not about or exactly 0.5W. For example, the scale pattern offset may advantageously be in the range of 0 +/-0.25W. In some embodiments, it may be even more advantageous for the scale pattern offset STO to be zero, which corresponds to the configuration of a conventional scale. (in conventional scales, the signal modulating element is typically a narrow rectangular element or strip that extends across the full width of the scale pattern without interference or discontinuities or offsets.) conventional scales are more readily available at a lower price in each length than special scales having multiple tracks of different patterns or offsets.

Similar to detector portion 767, detector portion 967 is configured to be mounted proximate to and to move relative to pattern tracks FPT and SPT in the measurement axis direction and includes a field generating coil configuration FGC and at least one corresponding sensing coil configuration SCC that provides signal components having corresponding spatial phases. The field generating coil configuration FGC is only briefly described here. The field generating coil configuration FGC may be fixed on the substrate and include: a first track field generating coil portion FTFGCP configured to provide a varying first magnetic flux in a first inner region FINTA aligned with the first pattern track FPT in response to a coil drive signal; and a second track field generating coil portion STFGCP configured to provide a varying second magnetic flux in a second inner region SINTA aligned with the second pattern track SPT in response to the coil driving signal. In detector portion 967, the second changing magnetic flux has a field polarity opposite to the first changing magnetic flux. The field generating coil configuration FGC may advantageously be constructed according to the principles outlined previously. However, in various embodiments, such design principles are merely exemplary and not limiting.

The sensing coil configuration SCC of detector portion 967 may be similar to that of detector portion 767, and may be similarly understood, except for certain differences described below.

Briefly summarizing some similar aspects, the sensing coil configuration SCC shown in fig. 9 includes sensing elements SEN that each include a first track winding or winding portion FTSEN and a second track winding or winding portion STSEN. For example, SEN13 may be described as including a first rail positive winding (or winding portion) FTSEN13 and a second rail positive winding (or winding portion) STSEN 13. A group or cluster of windings (or winding portions) FTSEN aligned with the first (track) inner region FINTA provides one embodiment of a first track first spatial phase sensing coil configuration FTFSPSCCF. A group or cluster of windings (or winding portions) aligned with a second (track) inner region SINTA provides one embodiment of a second track first spatial phase sensing coil configuration STFSPSCCF. First and second track first spatial-phase sensing coil configurations FTFSPSCCF and STFSPSCCF together form a total sensing coil configuration SCC that is configured such that, in cooperation with scale pattern 980, all signal components generated in each winding or winding portion (e.g., FTSEN and STSEN) have the same spatial phase.

With respect to the differences from detector portion 767, detector portion 967 includes certain added and/or changed features configured for compatible operation with scale pattern 980, which has a scale track pattern offset STO that is different from scale pattern 780. In particular, first and second track first spatial phase sensing coil configurations FTFSPSCCF and STFSPSCCF are arranged in the x-axis direction according to a winding offset WO STO +/-0.5W, where STO is a particular scale track pattern offset STO for a particular implementation of scale pattern 980. As outlined before for the embodiment shown in fig. 9, the scale track pattern offset STO is not always 0.5W and it is advantageously within the range 0+/-0.25W (e.g. as shown in fig. 9), and even more advantageously may be zero. As can be seen in the embodiment shown in fig. 9, first track first spatial phase signal sensing coil configuration FTFSPSCCF and second track first spatial phase signal sensing coil configuration STFSPSCCF define first and second sensing spans FSS and SSS, respectively, in the x-axis direction. In contrast to the previous embodiments, the first and second sensing spans FSS and SSS are not aligned with each other in the x-axis direction and are not symmetrically positioned with respect to each other with respect to a boundary line in the x-axis direction between the first and second pattern tracks FPT and SPT. Alternatively, their spans FSS and SSS are offset from each other by the winding offset WO. In the particular embodiment shown in the lower part of fig. 9, in each sensing element SEN the first track winding FTSEN is offset WO from the second track winding STSEN.

In the particular embodiment shown in fig. 9, each of first and second track first spatial phase-signal sensing coil configurations FTFSPSCCF and STFSPSCCF is configured to provide the same number of positive and negative windings (winding portions) that are interleaved without interference along the x-axis direction. However, the '990 and' 130 patents explain pitch compensation in terms of imaginary interleaved positive and negative pole regions in the sense coil configuration. The respective pitch compensated sense coil configuration may have equal numbers of positive and negative pole windings, but the windings need not be distributed in each pole region. For example, in some pitch balanced configurations, one positive polarity region may include two positive polarity windings and the other positive polarity region may be empty. Some of the principles may be combined with various principles and features disclosed herein. Thus, the particular undisturbed and uniform first and second track first spatial phase signal sensing coil configurations FTFSPSCCF and STFSPSCCF shown in FIG. 9 are exemplary only and not limiting. More generally, a first track first spatial phase signal sensing coil configuration FTFSPSCC disposed in the first interior region may include a set of N positive windings distributed in a positive winding region that repeats in the x-axis direction corresponding to the spatial wavelength W, and a set of N negative windings distributed in a negative winding region that alternates with the positive winding region and repeats in the x-axis direction corresponding to the spatial wavelength W, where N is an integer that is at least 2. The positive and negative pole windings (e.g., FTSEN1-FTSEN24) are each configured to respond to local effects on the changing magnetic flux provided by adjacent field attenuating elements (e.g., signal modulating elements SME) or field sustaining elements and to provide a signal contribution to a first track first spatial phase signal component provided by a first track first spatial phase signal sensing coil configuration FTFSPSCCF (e.g., at detector signal output connections SDS1 and SDS 2). Similarly, second track first spatial phase-signal sensing coil configuration STFSPSCCF arranged in second inner region SINTA may include a set of M positive windings distributed in a positive winding region that repeats in the x-axis direction corresponding to spatial wavelength W, and a set of M negative windings distributed in a negative winding region that alternates with the positive winding region and repeats in the x-axis direction corresponding to spatial wavelength W, where M is an integer that is at least 2. The positive and negative pole windings (e.g., STSEN1-STSEN24) are each configured to respond to local effects on the changing magnetic flux provided by adjacent field attenuating elements (e.g., signal modulating elements SME) or field sustaining elements and to provide a signal contribution to a second track first spatial phase signal component provided by second track first spatial phase signal sensing coil configuration STFSPSCCF (e.g., at detector signal output connections SDS1 and SDS 2). In various embodiments, N ═ M is advantageous. However, in some embodiments, this is not strictly necessary.

It will be appreciated that in the particular embodiment shown in fig. 9, each sensing element SEN comprises a winding or winding portion FTSEN and STSEN having a winding offset WO STO +/-0.5W and providing the same sensing loop polarity in the first and second inner regions FINTA and SINTA. Since the polarity of the magnetic flux generated in the first inner region FINTA is opposite to the polarity of the magnetic flux generated in the second inner region SINTA, this interacts with the pattern of signal modulating elements SME having scale track pattern offsets STO in the first and second track patterns FTP and STP of the scale pattern 980 to produce an enhanced signal contribution in each sensing element SEN. Additionally, it should be appreciated that starting from the start end (e.g., the left end in fig. 9) along sensing coil configuration SCC, first track first spatial-phase signal sensing coil configuration FTFSPSCCF has a configuration in which its start end winding (e.g., FTSEN1) along first track FPT has a first winding polarity (e.g., positive), second track first spatial-phase signal sensing coil configuration STFSPSCCF has a configuration in which its start end winding (e.g., STSEN1) along second track SPT has a first winding polarity (e.g., positive), and the start end windings along the first and second tracks are offset from each other in the x-axis direction by a winding offset WO STO +/-0.5W. This particular feature is important to compensate for or eliminate signal offset components that could otherwise result from static or dynamic "pitch" misalignment of the detector sections 967 relative to the scale pattern 980. Pitch misalignment (pitch misalignment) refers to the angle at which the detector section 967 is tilted to rotate about the Y-axis so that it is not parallel to the plane of the scale pattern 980. The inventors have discovered that, in addition to the spacing compensation considerations disclosed in the '990 and/or' 130 patents, additional considerations not previously recognized relate to slight differences in the effects of the field attenuating elements and the field sustaining elements of the scale pattern (e.g., scale pattern 780 or 980). In addition to another, different, previously known spacing compensation consideration, a sensing coil configuration SCC constructed in accordance with the principles outlined above addresses this spacing compensation consideration.

FIG. 10 is a plan view illustrating a sixth exemplary embodiment of a detector portion 1067 that is also compatible with the previously described scale pattern 980. The detector portion 1067 has similar characteristics and components as the detector portion 867 of fig. 8 and the detector portion 967 of fig. 9, and its design and operation are configured to implement the various design principles disclosed and claimed herein. In particular, similar elements are designated by reference numerals or numbers in fig. 10, similar or identical to those in fig. 8 and/or 9 or other figures herein, and may be understood to operate similarly unless specifically noted below. Therefore, only the significant differences of the detector portion 1067 will be described below. The detector portion 1067, in combination with the scale pattern 980, provides some advantages similar to those previously outlined with reference to the detector portion 967.

Similar to detector portions 867 and 967, detector portion 1067 is configured to be mounted proximate to and to move relative to pattern tracks FPT and SPT along the measurement axis direction and includes a field generating coil configuration FGC and at least one corresponding sensing coil configuration SCC that provides signal components having corresponding spatial phases. The field generating coil configuration FGC is only briefly described here. The field generating coil configuration FGC may be fixed on the substrate and in the shown embodiment comprises a first track field generating coil portion FTFGCP and a second track field generating coil portion STFGCP configured to provide a varying magnetic flux of the same polarity in a first inner region FINTA along the first pattern track FPT and in a second inner region SINTA along the second pattern track SPT. The field generating coil configuration FGC may advantageously be constructed according to the principles outlined previously. However, in various embodiments, such design principles are merely exemplary and not limiting. In some embodiments, because the first track field generating coil portion FTFGCP and the second track field generating coil portion STFGCP provide the same varying magnetic flux polarity, a single winding around the sensing coil configuration SCC may be considered to provide two "coil portions" without the need to use the first and second track inner elongate portions FTIEP and stibep. Such a configuration may not provide some of the advantages outlined previously, but may be sufficient in some implementations.

The sensing coil configuration SCC of detector portion 1067 may be similar to the sensing coil configuration of detector portion 867, and may be similarly understood, except for certain differences described below.

Briefly summarizing some similar aspects, the sensing coil configuration SCC shown in fig. 10 includes sensing elements SEN that each include a first track winding or winding portion FTSEN and a second track winding or winding portion STSEN. For example, SEN13 may be described as including a first rail positive winding (or winding portion) FTSEN13 and a second rail negative winding (or winding portion) STSEN 13. A group or cluster of windings (or winding portions) FTSEN aligned with the first (track) inner region FINTA provides one embodiment of a first track first spatial phase sensing coil configuration FTFSPSCCF. A group or cluster of windings (or winding portions) aligned with a second (track) inner region SINTA provides one embodiment of a second track first spatial phase sensing coil configuration STFSPSCCF. First and second track first spatial-phase sensing coil configurations FTFSPSCCF and STFSPSCCF together form a total sensing coil configuration SCC that is configured such that, in cooperation with scale pattern 980, all signal components generated in each winding or winding portion (e.g., FTSEN and STSEN) have the same spatial phase.

With respect to differences compared to the detector portion 867, the detector portion 1067 includes certain added and/or changed features configured for compatible operation with the scale pattern 980 having a scale track pattern offset STO that is different from the scale pattern 780. In particular, first and second track first spatial phase sensing coil configurations FTFSPSCCF and STFSPSCCF are arranged in the x-axis direction according to a winding offset WO STO +/-0.5W, as can be appreciated from the principles previously described with respect to winding offset WO in detector portion 967. As outlined before, the scale track pattern offset STO for the scale pattern 980 is not always 0.5W, and it is advantageously within the range 0+/-0.25W, and even more advantageously may be zero. For compatibility with such scale patterns 980, in the detector portion 1067, the first and second sensing spans FSS and SSS are not aligned with each other in the x-axis direction and are not positioned symmetrically with respect to each other with respect to a boundary line in the x-axis direction between the first and second pattern tracks FPT and SPT. Alternatively, their spans FSS and SSS are offset from each other by the winding offset WO. In the particular embodiment shown in the lower part of fig. 9, in each sensing element SEN the first track winding FTSEN is offset WO from the second track winding STSEN.

In the particular embodiment shown in fig. 10, each of first and second track first spatial phase-signal sensing coil configurations FTFSPSCCF and STFSPSCCF is configured to provide the same number of positive and negative windings (winding portions) that are interleaved without interference along the x-axis direction. However, the particular undisturbed and uniform first and second track first spatial-phase signal sensing coil configurations FTFSPSCCF and STFSPSCCF shown in FIG. 10 are exemplary only and not limiting for the reasons outlined previously with reference to detector portion 967. More generally, first track first spatial phase signal sensing coil configuration FTFSPSCCF disposed in the first interior region may include a set of N positive windings distributed in a positive winding region that repeats in the x-axis direction corresponding to spatial wavelength W, and a set of N negative windings distributed in a negative winding region that alternates with the positive winding region and repeats in the x-axis direction corresponding to spatial wavelength W, where N is an integer that is at least 2. The positive and negative pole windings (e.g., FTSEN1-FTSEN24) are each configured to respond to local effects on the changing magnetic flux provided by adjacent field attenuating elements (e.g., signal modulating elements SME) or field sustaining elements and to provide a signal contribution to a first track first spatial phase signal component provided by a first track first spatial phase signal sensing coil configuration FTFSPSCCF (e.g., at detector signal output connections SDS1 and SDS 2). Similarly, second track first spatial phase-signal sensing coil configuration STFSPSCCF arranged in second inner region SINTA may include a set of M positive windings distributed in a positive winding region that repeats in the x-axis direction corresponding to spatial wavelength W, and a set of M negative windings distributed in a negative winding region that alternates with the positive winding region and repeats in the x-axis direction corresponding to spatial wavelength W, where M is an integer that is at least 2. The positive and negative pole windings (e.g., STSEN1-STSEN24) are each configured to respond to local effects on the varying magnetic flux provided by adjacent field attenuating elements (e.g., signal modulating elements SME) or field sustaining elements and to provide a signal contribution to a second track first spatial phase signal component provided by second track first spatial phase signal sensing coil configuration STFSPSCCF (e.g., at detector signal output connections SDS1 and SDS 2). In various embodiments, N ═ M is advantageous. However, in some embodiments, this is not strictly necessary.

It will be appreciated that in the particular embodiment shown in fig. 9, each sense element SEN comprises a winding or winding portion FTSEN and STSEN having a winding offset WO STO +/-0.5W and providing opposite sense loop polarities in the first and second inner regions FINTA and SINTA. Since the polarity of the magnetic flux generated in the first inner region FINTA is the same as the polarity of the magnetic flux generated in the second inner region SINTA, this interacts with the pattern of signal modulating elements SME having scale track pattern offsets STO in the first and second track patterns FTP and STP of the scale pattern 980 to produce an enhanced signal contribution in each sensing element SEN. Additionally, it will be appreciated that starting from the start end (e.g., the left end in fig. 10) along sensing coil configuration SCC, first track first spatial-phase signal sensing coil configuration FTFSPSCCF has a configuration in which its start end winding (e.g., FTSEN1) along first track FPT has a first winding polarity (e.g., positive), second track first spatial-phase signal sensing coil configuration STFSPSCCF has a configuration in which its start end winding (e.g., STSEN1) along second track SPT has a second winding polarity (e.g., positive) opposite the first winding polarity, and the start end windings along the first and second tracks are offset from each other in the x-axis direction by a winding offset WO STO +/-0.5W. This particular feature is important to compensate for or eliminate signal offset components that could otherwise result from static or dynamic "pitch" misalignment of the detector portion 1067 relative to the scale pattern 980, in accordance with the principles outlined previously with reference to the detector portion 967.

FIG. 11 is a plan view illustrating a seventh exemplary embodiment of a detector portion 1067 that is functionally similar to the detector portion 967 and is also compatible with the scale pattern 980 previously described. Similar elements are designated by reference numerals or numbers in fig. 11, similar or identical to those in fig. 9, and may be understood to operate similarly. The detector portion 1167 and compatible scale pattern provide some advantages similar to those previously described for the detector portion 967.

The field generating coil configuration FGC of detector portion 1167 may be similar to or the same as that of detector portion 967. Only the significant differences of detector portion 1167 as compared to detector portion 967 will be described below.

In detector portion 967, sensing coil configuration SCC includes first and second track windings FTSEN and STSEN arranged in pairs as part of respective sensing loops referred to as sensing elements SEN. In one manner of describing this arrangement, in detector portion 967, the first track winding FTSEN located in the responsive winding region of the first track first spatial phase signal sensing coil configuration FTFSPSCC includes first and second conductor segments aligned transverse to the x-axis direction in the first inner region FINTA. The first conductor segments are connected in series by a first series connection to output a sense current directly to a conductor segment (e.g., of the second track winding portion STSEN) aligned transverse to the x-axis direction in the second inner region SINTA that forms part of a winding of the second track first spatial phase signal sensing coil construction STFSPSCC (e.g., of the second track winding portion STSEN). Furthermore, the second conductor segments are connected in series by a second series connection to input a sense current directly from a conductor segment (e.g., of the second track winding portion STSEN) aligned transverse to the x-axis direction in the second inner region SINTA, which forms part of a winding (e.g., of the second track winding portion STSEN) of the second track first spatial phase signal sensing coil configuration STFSPSCC.

In contrast, in detector portion 1167, sensing coil configuration SCC includes first and second track windings FTSEN and STSEN that are disposed "separately" in first and second track first spatial phase signal sensing coil configurations FTFSPSCC and STFSPSCC, which are connected in series only at their ends, as shown to the right in fig. 11. One exemplary configuration for conductors for providing the first and second track first spatial phase signal sensing coil configurations FTFSPSCC and STFSPSCC is shown at the bottom of fig. 11. Otherwise, it should be understood that detector portion 1167 has similar construction features and provides similar advantages provided in accordance with the principles previously outlined with reference to detector portion 967.

Fig. 12 is a plan view illustrating an eighth exemplary embodiment of a detector portion 1267 that is functionally similar to the detector portion 1067 and that is also compatible with the scale pattern 980 previously described. Similar elements are designated by reference numerals or numbers in fig. 12, similar or identical to those in fig. 10, and may be understood to operate similarly. The detector portion 1267 and compatible scale pattern provide some advantages similar to those previously described for the detector portion 1067.

The field generating coil configuration FGC of the detector portion 1267 may be similar to or the same as that of the detector portion 1067. Only the significant differences of the detector portion 1267 as compared to the detector portion 1067 will be described below.

In detector portion 1267, sense coil configuration SCC includes first and second track windings FTSEN and STSEN arranged in pairs as part of respective sense loops referred to as sense elements SEN. In one way of describing this arrangement, in the detector portion 1067, the first track winding FTSEN located in the responsive winding region of the first track first spatial phase signal sensing coil configuration FTFSPSCC includes first and second conductor segments aligned transverse to the x-axis direction in the first inner region FINTA. The first conductor segments are connected in series by a first series connection to output a sense current directly to a conductor segment (e.g., of the second track winding portion STSEN) aligned transverse to the x-axis direction in the second inner region SINTA that forms part of a winding of the second track first spatial phase signal sensing coil construction STFSPSCC (e.g., of the second track winding portion STSEN). Furthermore, the second conductor segments are connected in series by a second series connection to input the sense current directly from a conductor segment (e.g., of a second track winding portion STSEN) aligned transverse to the x-axis direction in the second inner region SINTA that forms part of the windings of the second track first spatial phase signal sensing coil configuration STFSPSCC (e.g., the second track winding portion STSEN). The first and second series connections are provided with an intersection or a twist in the region between the first and second inner regions FINTA and SINTA.

In contrast, in detector portion 1267, sensing coil configuration SCC includes first and second track windings FTSEN and STSEN that are disposed "separately" in first and second track first spatial phase signal sensing coil configurations FTFSPSCC and STFSPSCC, which are connected in series only at their ends, as shown to the right in fig. 12. One exemplary configuration for conductors for providing the first and second track first spatial phase signal sensing coil configurations FTFSPSCC and STFSPSCC is shown at the bottom of fig. 12. Otherwise, it should be understood that the detector portion 1267 has similar construction features and provides similar advantages provided in accordance with the principles previously outlined with reference to the detector portion 1067.

FIG. 13 is a plan view illustrating a ninth exemplary embodiment of a detector portion 1367 that is functionally similar to the detector portion 1167 and is also compatible with the scale pattern 980 previously described. Similar elements are designated by reference numerals or numbers in fig. 13, similar or identical to those in fig. 11, and may be understood to operate similarly. The detector portion 1367 and compatible scale pattern provide some advantages similar to those previously described for the detector portion 1167.

The field generating coil configuration FGC of detector portion 1367 may be similar to or identical to that of detector portion 1167. Which is shown with the same length along the x-axis direction for convenient comparison with detector 1167, it is understood that it may be significantly shorter if desired due to the reduced length of the sensing coil configuration SCC in detector portion 1367. Only the significant differences of detector portion 1367 as compared to detector portion 1167 will be described below.

In detector portion 1167 (and in detector portion 967), the first and second track first spatial phase signal sensing coil configurations FTFSPSCC and STFSPSCC are each configured with positive and negative windings (winding portions) in alternating positive and negative pole regions that are interleaved without interference along the x-axis. In addition, starting from a starting end (e.g., the left end in the figure) along the sense coil configuration, first track first spatial phase signal sense coil configuration FTFSPSCC has a configuration in which its starting end winding along first track FPT has a first winding polarity and its ending end winding (e.g., the right end in the figure) has a second winding polarity that is opposite the first winding polarity; and the second track first spatial phase signal sensing coil configuration STFSPSCC has a configuration in which its start end winding along the second track SPT has a first winding polarity and its end winding has a second winding polarity opposite the first winding polarity.

However, as outlined previously, the particular undisturbed and consistent first and second track first spatial phase signal sensing coil configurations in detector portion 1167 (and in detector portion 967) are exemplary only and not limiting. Detector portion 1367 illustrates one of a number of possible alternative configurations. In the particular embodiment shown in fig. 13, the first track first spatial phase signal sensing coil configuration FTFSPSCCF includes four first track windings FTSEN. The positive first track windings FTSEN1 and FTSEN4 are located in respective positive winding regions, and the two negative first track windings FTSEN2 and FTSEN3 are located in a negative winding region therebetween. Second track first spatial phase signal sensing coil configuration STFSPSCCF includes four second track windings STSEN. The positive second track windings STSEN1 and FTSEN4 are located in respective positive winding regions, and the two negative first track windings STSEN2 and STSEN3 are located in a negative winding region therebetween.

As a broader description of the sensing coil configuration SCC of detector portion 1367 and the various alternatives that may be used in the cover position, starting from the beginning end (e.g., the left end in fig. 13) along sensing coil configuration SCC, the first track first spatial phase signal sensing coil configuration FTFSPSCC has a configuration in which its beginning end winding (e.g., FTSEN1) along first track FPT has a first winding polarity (e.g., positive) and its ending end winding (e.g., FTSEN4) also has that first winding polarity (e.g., positive), at least one winding region between its beginning end winding and its ending end winding including two windings (e.g., FTSEN2 and FTSEN3) having a second winding polarity (e.g., negative) opposite to the first winding polarity. The second track first spatial phase signal sensing coil configuration STFSPSCC has a configuration in which its start end winding along the second track has a first winding polarity and its end winding also has a first winding polarity, at least one winding region between its start end winding and its end winding including two windings having a second winding polarity opposite to the first winding polarity.

It may be noted that fig. 13 includes a first set of detector signal output connections SDS1 and SDS2 for the first track first spatial phase signal sensing coil configuration FTFSPSCC, and a second set of detector signal output connections SDS1 and SDS2 for the second track first spatial phase signal sensing coil configuration STFSPSCC. These may convey and/or output a first track first spatial phase signal component and a second track first spatial phase signal component, respectively. In each such embodiment, signal processing circuitry may be operatively connected to detector portion 1367, and the first track first spatial phase signal component and the second track first spatial phase signal component available at these sets of connections may be connected to inputs of the signal processing circuitry and combined by signal processing to form a combined first spatial phase signal. In various embodiments disclosed herein, this is an alternative method of combining a first track first spatial phase signal component and a second track first spatial phase signal component to form a combined first spatial phase signal. In contrast, the detector portion shown in fig. 9-12 utilizes a further alternative approach in which the respective windings of the first track first spatial phase signal sensing coil configuration ftfspsc and the second track first spatial phase signal sensing coil configuration stfspsc comprise respective portions of continuous conductors in which the first track first spatial phase signal component and the second track first spatial phase signal component inherently combine to form a combined first spatial phase signal that is available at a single set of detector signal output connections SDS1 and SDS 2. It will be appreciated that any of the detector portion configurations shown in fig. 9-13 may be readily adapted to any of the methods for providing a combined first spatial phase signal.

It should be appreciated that a detector portion 1367 that is functionally similar to detector portion 1167 suggests a similar detector portion that is functionally similar to detector portion 1267. In such a detector portion, the field generating coil configuration FGC will be similar or identical to the detector portion 1267, although it may have a reduced length in various embodiments. In detector portion 1267 (and in detector portion 1067), the first and second track first spatial phase signal sensing coil configurations FTFSPSCC and STFSPSCC are each configured with positive and negative windings (winding portions) in alternating positive and negative pole regions that are interleaved without interference along the x-axis. In addition, starting from a starting end (e.g., the left end in the figure) along the sense coil configuration, first track first spatial phase signal sense coil configuration FTFSPSCC has a configuration in which its starting end winding along first track FPT has a first winding polarity and its ending end winding (e.g., the right end in the figure) has a second winding polarity that is opposite the first winding polarity; and the second track first spatial phase signal sensing coil configuration STFSPSCC has a configuration in which its start end winding along the second track SPT has a second winding polarity opposite to the first winding polarity and its end winding has the first winding polarity.

In contrast, as a general description of various functionally similar sense coil configurations SCC that may be used in place of the sense coil configuration previously described for detector portion 1267, a first spatial phase signal sense coil configuration along a first track thereof has, starting at a start end along sense coil configuration SCC, a configuration in which its start end winding along the first track has a first winding polarity and its end winding also has a first winding polarity, at least one winding region between its start end winding and its end winding including two windings having a second winding polarity opposite to the first winding polarity; the second track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the first track has a second winding polarity opposite to the first winding polarity and its end winding also has a second winding polarity opposite to the first winding polarity, at least one winding region between its start end winding and its end winding including two windings having the first winding polarity.

It will be appreciated that in the detector portion configurations shown in fig. 9-13, the windings of the first and second track first spatial phase signal sensing coils FTFSPSCC and STFSPSCC comprise conductors fabricated in multiple layers of a printed circuit board, wherein the conductors include leads connected between different layers of the printed circuit board and no leads are included in portions of the windings located in the first and second inner regions FINTA and SINTA. This is particularly advantageous because the signal imbalances associated with loop area imbalances, which are otherwise associated with non-ideal conductor routing required to accommodate the leads, are largely eliminated because they fall outside the primary signal generating regions of the first and second track first spatial-phase signal sensing coils FTFSPSCC and STFSPSCC in the first and second inner regions FINTA and SINTA.

While preferred embodiments of the invention have been shown and described, numerous variations in the illustrated and described arrangements of features and sequences of operations will be apparent to those skilled in the art based on this description. Various modifications may be made to implement the principles disclosed herein.

As an example, the exemplary principles described and emphasized with reference to fig. 9-13 are illustrated in combination with various exemplary dimensions and dimensional relationships along the y-axis direction described and emphasized with reference to fig. 7 and 8. However, such combinations are exemplary only and not limiting. More generally, the exemplary principles described and emphasized with reference to fig. 9-13 may provide some benefits independent of such constraints of dimensions and dimensional relationships in the y-axis direction when used in other detector portion configurations, as will be apparent to those skilled in the art based on the principles disclosed herein.

As a further example, it will be appreciated that in various embodiments, the signal modulating element SME may comprise a ring element or plate element, or a variation in material properties, and/or in various embodiments may have a dimension of W/2 along the x-axis direction, or greater or less than W/2, to produce a desired periodic signal pattern. As a further example, it will be appreciated that the various features and principles disclosed herein may be applied to a rotary position encoder in which the measurement axis and radial directions of the circle are similar to the x-axis and y-axis directions referred to in the specification.

More generally, the various embodiments and features described above can be combined to provide further embodiments. All U.S. patents and U.S. patent applications referenced in this specification are hereby incorporated by reference in their entirety. Aspects of the embodiments can be modified, if necessary, to employ concepts of the various patents and applications to provide yet further embodiments.

These and other changes can be made to the embodiments in light of the above description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled.

Claims (12)

1. An electronic position encoder usable for measuring a relative position between two elements along a measurement axis direction, the measurement axis direction coinciding with an x-axis direction, the electronic position encoder comprising:

a scale extending in a measurement axis direction and including a signal modulation scale pattern including first and second pattern tracks arranged parallel to each other, each pattern track including a field attenuating element that locally attenuates varying magnetic flux to a relatively large extent and a field maintaining element that locally attenuates varying magnetic flux to a relatively small extent or locally enhances varying magnetic flux, and wherein the field attenuating element and the field maintaining element are interleaved in a periodic pattern having a spatial wavelength W in an x-axis direction; and

a detector section configured to be mounted adjacent to the first and second pattern rails and to move relative to the first and second pattern rails in a measurement axis direction, the detector section including:

a field generating coil configuration comprising at least one field generating loop fixed on the substrate, the field generating coil configuration configured to provide a varying first magnetic flux in a first interior region aligned with the first pattern track in response to a coil drive signal and to provide a varying second magnetic flux in a second interior region aligned with the second pattern track in response to a coil drive signal;

a sensing coil construction comprising:

a first track first spatial phase signal sensing coil configuration arranged in the first interior region comprising a set of N positive windings distributed in a positive winding region that repeats in the x-axis direction corresponding to the spatial wavelength W and a set of N negative windings distributed in a negative winding region that alternates with the positive winding region and repeats in the x-axis direction corresponding to the spatial wavelength W, wherein N is an integer of at least 2, and wherein the positive and negative windings each respond to a local effect on the varying magnetic flux provided by an adjacent field attenuating or field maintaining element and provide a signal contribution to a first track first spatial phase signal component provided by the first track first spatial phase signal sensing coil configuration; and

a second track first spatial phase signal sensing coil configuration arranged in the second interior region comprising a set of M positive windings distributed in a positive winding region that repeats in the x-axis direction corresponding to the spatial wavelength W and a set of M negative windings distributed in a negative winding region that alternates with the positive winding region and repeats in the x-axis direction corresponding to the spatial wavelength W, wherein M is an integer of at least 2, and wherein the positive and negative windings each respond to a local effect on the varying magnetic flux provided by an adjacent field attenuating or field maintaining element and provide a signal contribution to a second track first spatial phase signal component provided by the second track first spatial phase signal sensing coil configuration;

wherein:

the first and second track first spatial-phase signal sensing coil configurations define first and second sensing spans, respectively, in the x-axis direction, and the first and second sensing spans are not aligned with each other in the x-axis direction, and the first and second track first spatial-phase signal sensing coil configurations are not symmetric with each other about a boundary line between the first and second pattern tracks in the x-axis direction;

the periodic pattern of the second pattern track is aligned in the x-axis direction relative to the periodic pattern of the first pattern track, or is offset by a scale pattern offset STO that is not 0.5 x W; and is

The electronic position encoder is configured according to one of A) or B), wherein:

A)

the field generating coil configuration is configured to provide varying magnetic fluxes of opposite polarity in a first inner region along the first pattern track and in a second inner region along the second pattern track; and is

Starting from the start end along the sense coil configuration, the first track first spatial-phase-signal sense coil configuration has a configuration in which its start end winding along the first track has a first winding polarity, the second track first spatial-phase-signal sense coil configuration has a configuration in which its start end winding along the second track has a first winding polarity, and the start end windings along the first and second tracks are offset from each other in the x-axis direction by a winding offset WO STO +/-0.5W; or

B)

The field generating coil configuration is configured to provide a varying magnetic flux of the same polarity in a first inner region along the first pattern track and in a second inner region along the second pattern track; and is

Starting from the start end along the sense coil configuration, the first track first spatial-phase-signal sense coil configuration has a configuration in which its start end winding along the first pattern track has a first winding polarity, the second track first spatial-phase-signal sense coil configuration has a configuration in which its start end winding along the second pattern track has a second winding polarity opposite to the first winding polarity, and the start end windings along the first and second tracks are offset from each other in the x-axis direction by a winding offset WO STO +/-0.5W.

2. The electronic position encoder of claim 1, wherein the electronic position encoder is constructed in accordance with a).

3. An electronic position encoder according to claim 2 wherein the scale pattern offset STO is in the range 0+/-0.25W and starts from the start end along the sensing coil configuration:

the first track first spatial phase signal sensing coil configuration has a configuration wherein its starting end winding along the first track has a first winding polarity and its ending end winding has a second winding polarity opposite to the first winding polarity; and is

The second track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the second track has a first winding polarity and its end winding has a second winding polarity opposite the first winding polarity.

4. An electronic position encoder according to claim 2 wherein the scale pattern offset STO is in the range 0+/-0.25W and starting from the start end along the sense coil configuration:

the first track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the first track has a first winding polarity and its end winding also has a first winding polarity, and at least one winding region between its start end winding and its end winding includes two windings having a second winding polarity opposite to the first winding polarity; and is

The second track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the second track has a first winding polarity and its end winding also has a first winding polarity, and at least one winding region between its start end winding and its end winding includes two windings having a second winding polarity opposite to the first winding polarity.

5. An electronic position encoder according to claim 2 wherein the scale pattern offset STO is in the range 0+/-0.25W and at least a majority of the windings in each winding region of the first track first spatial phase signal sensing coil comprise:

first conductor segments aligned transverse to the x-axis direction in a first inner region and connected in series by a first series connection to output a sense current directly to conductor segments forming part of a winding of a second-track first spatial-phase signal sensing coil aligned transverse to the x-axis direction in a second inner region; and

second conductor segments aligned transverse to the x-axis direction in the first inner region and connected in series by a second series connection to input a sensing current directly from conductor segments forming part of a winding of a second track first spatial-phase signal sensing coil aligned transverse to the x-axis direction in the second inner region; and

the windings of the first and second track first spatial phase signal sensing coils comprise conductors fabricated in printed circuit board layers, wherein the conductors comprise leads connected between different layers of the printed circuit board, and portions of the windings located in the first and second inner regions do not comprise leads.

6. The electronic position encoder of claim 1, wherein the electronic position encoder is constructed in accordance with B).

7. An electronic position encoder according to claim 6 wherein the scale pattern offset STO is in the range 0+/-0.25W and starting from the start end along the sense coil configuration:

the first track first spatial phase signal sensing coil configuration has a configuration wherein its starting end winding along the first track has a first winding polarity and its ending end winding has a second winding polarity opposite to the first winding polarity; and is

The second track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the second track has a second winding polarity opposite to the first winding polarity and its end winding has a first winding polarity.

8. An electronic position encoder according to claim 6 wherein the scale pattern offset STO is in the range 0+/-0.25W and starting from the start end along the sense coil configuration:

the first track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the first track has a first winding polarity and its end winding also has a first winding polarity, and at least one winding region between its start end winding and its end winding includes two windings having a second winding polarity opposite to the first winding polarity; and is

The second track first spatial phase signal sensing coil configuration has a configuration in which its start end winding along the second track has a second winding polarity opposite to the first winding polarity and its end winding also has a second winding polarity opposite to the first winding polarity, and at least one winding region between its start end winding and its end winding includes two windings having the first winding polarity.

9. An electronic position encoder according to claim 6 wherein the scale pattern offset STO is in the range 0+/-0.25W and at least a majority of the windings in each winding region of the first track first spatial phase signal sensing coil comprise:

first conductive segments aligned transverse to the x-axis direction in a first inner region and connected in series by a first series connection to output a sense current directly to conductor segments forming part of a winding of a second track first spatial-phase signal sensing coil aligned transverse to the x-axis direction in a second inner region; and

second conductor segments aligned transverse to the x-axis direction in the first inner region and connected in series by a second series connection to input a sensing current directly from conductor segments forming part of a winding of a second track first spatial-phase signal sensing coil aligned transverse to the x-axis direction in the second inner region, and

wherein the first and second series connections provide an intersection or twist in a region between the first and second inner regions, and the windings of the first and second track first spatial-signal sensing coils comprise conductors fabricated in a printed circuit board layer, wherein the conductors comprise leads connected between different layers of the printed circuit board and no leads are included in portions of the windings located in the first and second inner regions.

10. An electronic position encoder according to claim 1 wherein the first track first spatial phase signal component and the second track first spatial phase signal component are combined according to one of C) or D) to form a combined first spatial phase signal, wherein,

C) the respective windings of the first track first spatial phase signal sensing coil configuration and the second track first spatial phase signal sensing coil configuration comprise respective portions of a continuous conductor, and the first track first spatial phase signal component and the second track first spatial phase signal component are inherently combined in the continuous conductor to form a combined first spatial phase signal; or

D) The signal processing circuit is operatively connected to the detector section, and the first track first spatial phase signal component and the second track first spatial phase signal component are connected to an input of the signal processing circuit and combined by signal processing to form a combined first spatial phase signal.

11. The electronic position encoder of claim 1, wherein N-M.

12. An electronic position encoder according to claim 1 wherein the scale pattern offset STO is zero.

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