Transmit / receive configuration for electromagnetic induction encoders

Abstract

To provide an improved encoder configuration.SOLUTION: An electromagnetic induction encoder includes a scale and a detection unit. The detection unit includes a magnetic field generation coil (FGC) having elongated portions (EP) coupled to a generated magnetic field area (GFA) aligned with sensing winding in order to provide a position signal responsive to the scale that interacts with the generated magnetic field. A sensing element and the EP are made in a "front" layer of the detection unit. A transverse conductor portion (TCP) formed in a "rear" layer of the detection unit connects the EP of the FGC via interlayer connection. A shielding area in a layer between the front layer and the rear layer blocks at least half or more of a projection of the TCP towards the front layer in order to eliminate undesired signal effects. FGC interlayer connection creates a GFC interlayer connection stray field. A pair of the interlayer connection connecting a sensing winding signal to the rear layer of the detection unit is specially configured to mitigate the undesired signal effects that may result from coupling to the GFC interlayer connection stray field.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present disclosure relates to measuring instruments, and more particularly to electromagnetic inductive encoders that can be used in precision measuring instruments. [Background technology]

[0002] Various encoder configurations may include various types of optical, capacitive, magnetic, inductive, movement and / or position transducers. These transducers measure movement between the readhead and the scale using various geometric configurations of transmitters and receivers in the readhead. Magnetic and inductive transducers are desirable in many applications because they are relatively robust to contamination.

[0003] US Patent No. 5,399,663 describes an electromagnetic induction transducer that can be used for high precision applications. US Patent No. 5,399,663 and US Patent No. 5,399,677 describe an electromagnetic induction incremental caliper and linear scale that includes signal generation and processing circuitry. US Patent No. 5,399,663, US Patent No. 5,399,677 and US Patent No. 5,399,677 describe an electromagnetic induction absolute caliper and electronic tape measure that use an electromagnetic induction transducer. US Patent No. 5,399,677 describes an electromagnetic induction transducer that can be used for high precision applications, in which a parallel bisected scale and a set of multiple transmit and receive coils reduce certain signal offsets that can cause errors in the electromagnetic induction transducer. All of the above are incorporated herein by reference in their entirety. As described in these patents, the electromagnetic induction transducer can be manufactured using printed circuit board technology and is largely insensitive to dirt. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 6,011,389 [Patent Document 2] U.S. Pat. No. 5,973,494 [Patent Document 3] U.S. Patent No. 6,002,250 [Patent Document 4] U.S. Pat. No. 5,886,519 [Patent Document 5] U.S. Patent No. 5,841,274 [Patent Document 6] U.S. Pat. No. 5,894,678 [Patent Document 7] U.S. Pat. No. 7,906,958 Summary of the Invention [Problem to be solved by the invention]

[0005] However, such systems may be limited in their ability to provide a particular combination of features desired by a user, such as a combination of signal strength, small size, high resolution, cost, robustness to misalignment and dirt, etc. Encoder configurations that provide improved combinations of these and other features are desired. [Means for solving the problem]

[0006] 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.

[0007] An electromagnetic induction encoder is provided that can be used to measure a relative position between two elements along a measurement axis direction that coincides with an x-axis direction. In various embodiments, the electromagnetic induction encoder includes a scale, a detector, and a signal processor. The scale includes a signal modulation scale pattern that includes at least a first pattern track extending along the measurement axis direction and having a track width dimension along a y-axis direction orthogonal to the x-axis direction. In some embodiments, the signal modulation scale pattern includes the first pattern track and a second pattern track extending in the x-axis direction parallel to the first pattern track. Each pattern track includes signal modulation elements arranged to provide a spatially varying characteristic that changes as a periodic function of position along the x-axis direction.

[0008] The detector is mounted proximate to at least the first pattern track and configured to move along a measurement axis direction relative to at least the first pattern track. In various embodiments, the detector includes a multi-layer circuit element (e.g., a printed circuit board or a multi-layer circuit element) having a front surface that faces the scale during normal operation. The layers may include a shielded conductor layer(s), a shielding region layer(s), one or more receiving loop layers (typically two layers), and an extension layer(s). The detector includes a magnetic field generating coil, a conductive shielding region portion, a set of shielding layer conductor portions, and a sense winding portion.

[0009] A magnetic field generating coil (transmitter) is secured to the multi-layer circuit element. The magnetic field generating coil includes an input connecting the magnetic field generating coil to a signal processor for providing a coil drive signal, and at least one first track magnetic field generating coil section configured to nominally surround a first track generated magnetic field region nominally aligned with the first pattern track and generate a first track changing magnetic flux in the first track generated magnetic field region in response to the coil drive signal. The first track magnetic field generating coil section may be described as comprising a first track first side extension and a first track second side extension fabricated in one or more extension layers of the multi-layer circuit element and extending along an x-axis direction to a first side and a second side of the first track generated magnetic field region. The first track first side extension and the first track second side extension together extend across or define a first track extension length dimension along the x-axis direction, and a minimum separation in the y-axis direction between the first track first side extension and the first track second side extension defines a minimum width dimension of the first track generated magnetic field region. The magnetic field generating coil further comprises a set of extension inter-layer connections extending between the extension layer and the shielded conductor layer along a z-axis direction that is nominally normal to a front surface of the multilayer circuit element, the set consisting of a first end subset of extension inter-layer connections disposed at first ends of the first track first side extension and the first track second side extension of the magnetic field generating coil, and a second end subset of extension inter-layer connections disposed at second ends of the first track first side extension and the first track second side extension of the magnetic field generating coil. Each of the first end subset and second end subset of the extension layer connections is connected to a respective end of the first track first side extension and the first track second side extension of the magnetic field generating coil and is connected to the shield layer conductor portion for transmitting a coil drive signal therebetween.

[0010] The set of shielding layer conductors comprises a member fabricated in a shielded conductor layer of the multilayer circuit element. Several shielding layer conductors are included in the magnetic field generating coil. At least one such shielding layer conductor is a transverse conductor extending along a direction transverse to the x-axis direction. At least one such shielding layer transverse conductor spans at least a minimum separation in the y-axis direction between the first track first side extension and the second side extension, and is included in a conductor path connecting the first track first side extension and the second track second side extension in the first track magnetic field generating coil section.

[0011] The conductive shielding region configuration includes a shielded conductor layer and at least one first track conductive shielding region fabricated in a first track shielding region layer extending along a y-axis direction and located between the first track shielded conductor layer and one or more receiver loop layers of the multilayer circuit element with respect to a position along the z-axis direction. The conductive shielding region configuration includes at least one first track conductive shielding region interposed along the z-axis direction between the receiver loop layer and a shielded layer crossing conductor portion that spans at least a minimum separation in the y-axis direction. The first track conductive shielding region is configured to block at least half or more of an area of ​​a z-axis projection of the shielded layer crossing conductor portion toward the receiver loop layer along the z-axis direction.

[0012] The sensing winding section comprises at least two sets of spatial phase sensing windings each having a sensing element and a spatial phase signal connection arrangement. Each of the spatial phase sensing windings comprises a plurality of sensing elements each having a conductive receiving loop connected in series and fabricated in one or more receiving loop layers of the multilayer circuit element. The conductive receiving loops are distributed along the x-axis direction, and at least a first track portion of the conductive receiving loops is provided across a first track sensing element area nominally aligned with the first pattern track. The sensing elements in each of the spatial phase sensing windings are configured to provide a respective sensing signal or sensing signal contribution in response at least to a local influence on the first track changing magnetic flux provided by an adjacent signal modulating element of the scale pattern. Each spatial phase signal connection arrangement comprises a pair of sensing signal inter-layer connections extending along the z-axis direction between the receiving loop layer and the shielded conductor layer. One of the pair of sensing signal inter-layer connections is connected (e.g., directly or via a conductor portion disposed in the receiving loop layer) to a first signal connection node of its respective spatial phase sensing winding and connected to the signal processing section via a respective shielding layer conductor portion. The other of the pair of detection signal inter-layer connections is connected to the second signal connection node of the respective spatial phase detection winding (e.g., directly or via a conductor portion disposed in the receiving loop layer) and is connected to the signal processing unit via the respective shielding layer conductor portion, whereby the pair of detection signal inter-layer connections are configured to input the detection signal from the respective spatial phase detection winding to the signal processing unit.

[0013] The signal processing unit may be operatively connected to the detection unit to provide a coil drive signal, and is configured to determine the relative position of the detection unit and the signal modulation scale pattern based on a detection signal input from the detection unit.

[0014] In various embodiments consistent with the principles disclosed herein, the detection portion is configured as follows. a detection signal interlayer connection of each spatial phase signal connection arrangement is located outside and beyond an edge of a first track generated magnetic field region with respect to a position along an x-axis direction; when transmitting a coil drive signal, each subset of extension inter-layer connections generates a respective inter-layer connection magnetic stray field that includes inter-layer connection stray flux components oriented in an xy plane parallel to the x-axis and y-axis; each detection signal inter-layer connection pair in each spatial phase signal connection arrangement defines a respective inter-layer connection inductive coupling region plane that nominally passes through a central axis of each inter-layer connection of the pair and further defines an inter-layer connection inductive coupling region located within the plane between the inter-layer connections of the pair; And the detection signal inter-layer connection pairs of each spatial phase signal connection arrangement are configured to compensate or minimize their respective detection signal components resulting from receiving inter-layer connection stray magnetic flux via their respective inter-layer connection inductive coupling regions using at least one of arrangement characteristics A) or B).

[0015] Here, in arrangement characteristic A), the detection signal inter-layer connection pairs of each spatial phase signal connection arrangement are configured such that their inter-layer connection inductive coupling region planes are at an angle of up to 25 degrees to each other in the XY plane, and the detection signal inter-layer connection pairs of each spatial phase signal connection arrangement are positioned close to each other in the XY plane such that their inter-layer connection inductive coupling regions receive inter-layer connection stray magnetic flux components that similarly intersect in the XY plane.

[0016] Also, in arrangement characteristic B), the pairs of detection signal interlayer connections of each spatial phase signal connection arrangement are each configured such that their interlayer connection inductive coupling region planes are parallel to the XY plane and have an angle of up to 25 degrees in the XY plane with respect to the interlayer connection stray magnetic flux components passing through the central regions of their interlayer connection inductive coupling regions.

[0017] In some embodiments of the electromagnetic inductive encoder, the set of spatial phase sensing windings comprises at least three spatial phase sensing windings whose associated detection signal inter-layer connection pairs are configured according to arrangement characteristic A). In some such embodiments, the associated detection signal inter-layer connection pairs are configured such that their inter-layer connection inductive coupling areas differ by at most 20%. In some such embodiments, the associated detection signal inter-layer connection pairs are configured such that their inter-layer connection inductive coupling area planes are nominally parallel.

[0018] In some embodiments of the electromagnetic inductive encoder, the set of spatial phase sensing windings comprises at least two spatial phase sensing windings whose associated detection signal inter-layer connection pairs are each configured according to arrangement characteristic B). In some such embodiments, the associated detection signal inter-layer connection pairs are each configured such that their inter-layer connection inductive coupling area planes are parallel to the XY plane and have an angle of up to 10 degrees with respect to the inter-layer connection stray flux components passing through central areas of their inter-layer connection inductive coupling areas. In some such embodiments, the associated detection signal inter-layer connection pairs are configured such that their inter-layer connection inductive coupling areas differ by up to 20%.

[0019] In some "single track" embodiments according to arrangement characteristic B), a first end subset of extension inter-layer connections located at a first end of the magnetic field generating coil and a second end subset of extension inter-layer connections located at a second end of the magnetic field generating coil are each composed of two extension inter-layer connections connected to a first track first side extension and a first track second side extension. Some such single track embodiments may be configured as follows: each associated detection signal inter-layer connection pair may be configured such that their inter-layer connection inductive coupling region is located proximate to an XZ mid-plane that is parallel to the x-axis direction and the z-axis direction and aligned along the center of the first track generated magnetic field region with respect to the y-axis direction, and their inter-layer connection inductive coupling region planes are angled in the XY plane by at most 10 degrees with respect to the XZ mid-plane. In some such embodiments, each associated detection signal inter-layer connection pair may be configured such that their inter-layer connection inductive coupling region planes are nominally parallel to each other. In some such embodiments, associated detection signal inter-strata connection pairs are each configured such that their inter-strata connection inductive coupling areas differ by up to 20%.

[0020] In some embodiments of the electromagnetic inductive encoder, the set of spatial phase sensing windings comprises at least two spatial phase sensing windings, each associated pair of sensing signal interlayer connections being configured according to arrangement characteristic B).

[0021] In some embodiments, the electromagnetic induction encoder is of the "two track" type, comprising a first pattern track and a second pattern track, and the set of spatial phase sensing windings comprises at least two spatial phase sensing windings, each of which has its associated pair of sense signal inter-layer connections configured according to arrangement characteristic B), wherein the electromagnetic induction encoder comprises a first pattern track and a second pattern track, and the magnetic field generating coil comprises a first track magnetic field generating coil section aligned with the first pattern track and a similar second track magnetic field generating coil section aligned with the second pattern track. A first end subset of extension inter-layer connections disposed at a first end of the magnetic field generating coil and a second end subset of extension inter-layer connections disposed at a second end of the magnetic field generating coil each comprise four extension inter-layer connections connected to respective first track first side extensions and first track second side extensions and second track first side extensions and second track second side extensions. Two adjacent central extension inter-layer connections in each of the first end subset and the second end subset are connected to adjacent first track second side extensions and second track first side extensions, respectively, the magnetic field generating coils are configured such that currents of the coil drive signals flow in opposite directions in the two adjacent central extension inter-layer connections and the polarity of the magnetic field is the same in the first track generated magnetic field region and the second track generated magnetic field region, and the associated detection signal inter-layer connection pairs are each positioned such that their inter-layer connection inductive coupling regions are adjacent to an XY mid-plane configured to be parallel to the x-axis and z-axis directions and nominally midway between the two adjacent central extension inter-layer connections and / or nominally midway between the first track generated magnetic field region and the second track generated magnetic field region with respect to the y-axis direction, and their inter-layer connection inductive coupling region planes are configured to have an angle of at most 10 degrees in the XY plane with respect to the XZ mid-plane.

[0022] In some such two-track embodiments, each of the associated detection signal inter-layer connection pairs is configured such that their inter-layer connection inductive coupling region planes are nominally parallel to one another, hi some such embodiments, each of the associated detection signal inter-layer connection pairs is further configured such that their inter-layer connection inductive coupling regions differ by up to 20%.

[0023] In some embodiments, the inductive encoder is of the "two track" type, comprising a first pattern track and a second pattern track, and the set of spatial phase sensing windings comprises at least two spatial phase sensing windings, each of whose associated sense signal inter-layer connection pairs is configured according to arrangement characteristic B), wherein the magnetic field generating coil comprises a first track magnetic field generating coil section aligned with the first pattern track and a similar second track magnetic field generating coil section aligned with the second pattern track, and a first end subset of extension inter-layer connections disposed at a first end of the magnetic field generating coil and a second end subset of extension inter-layer connections disposed at a second end of the magnetic field generating coil each comprise four extension inter-layer connections connected to respective first track first side extensions and first track second side extensions and second track first side extensions and second track second side extensions. Two adjacent central extension inter-layer connections in each of the first end subset and the second end subset are connected to adjacent first track second side extensions and second track first side extensions, respectively, the magnetic field generating coils are configured such that currents of the coil drive signals flow in the same direction in the two adjacent central extension inter-layer connections and polarities of the magnetic fields are opposite in the first track generated magnetic field region and the second track generated magnetic field region, and + associated detection signal inter-layer connection pairs are each positioned such that their inter-layer connection inductive coupling regions are adjacent to an XZ mid-plane that is configured to be parallel to the x-axis and z-axis directions and nominally midway between the two adjacent central extension inter-layer connections and / or nominally midway between the first track generated magnetic field region and the second track generated magnetic field region with respect to the y-axis direction, and their inter-layer connection inductive coupling region planes are configured to have an angle of at most 10 degrees in the XY plane with respect to a YZ plane that is perpendicular to the XZ mid-plane.

[0024] In some such two-track embodiments, the associated detection signal interlayer connection pairs are each configured such that their interlayer connection inductive coupling region planes are nominally parallel to the YZ plane and their interlayer connection inductive coupling regions are intersected by the XZ mid-plane. In some such embodiments, the associated detection signal interlayer connection pairs are each further configured such that their interlayer connection inductive coupling regions differ by up to 20%.

[0025] In some embodiments according to principles disclosed herein, the detection signal interlayer connection pairs of the first spatial phase signal connection arrangement and the second spatial phase signal connection arrangement are configured according to arrangement characteristic B) and further configured according to arrangement characteristic A), respectively.

[0026] In various embodiments according to arrangement characteristic A) and / or arrangement characteristic B), each spatial phase signal connection arrangement may further include a pair of alignment conductors fabricated in a respective receiver loop layer such that: a first one of the pair of alignment conductors extends from a first portion of a conductive receiver loop of its associated spatial phase sensing winding to provide a first signal connection node at a location that connects to a first one of the pair of detection signal inter-layer connections associated with its spatial phase sensing winding; a second one of the pair of alignment conductors extends from a second portion of a conductive receiver loop of its associated spatial phase sensing winding to provide a second signal connection node at a location that connects to a second one of the pair of detection signal inter-layer connections associated with its spatial phase sensing winding; and the pair of alignment conductors are configured in the respective receiver loop layer such that at least half or more of their areas are aligned with one another along the z-axis direction.

[0027] It should be appreciated that the various embodiments outlined above may be particularly advantageous when used in combination with a configuration in which the first track sensing element area extends across a first track sensing element area long dimension along the x-axis direction that is longer than the first track extension long dimension, as disclosed with reference to Figures 4-8 herein and / or as disclosed in commonly assigned, pending U.S. application Ser. No. 16 / 863,543, which is incorporated herein by reference in its entirety.

[0028] It should be noted that the terms "nominal surround" or "encircle" as used herein apply to any generating coil section or other loop portion referred to herein, whether it is a complete or incomplete "loop," provided that it is configured to provide an operational coupling between the adjacent magnetic field or magnetic flux and the associated current flowing in that generating coil section or other loop portion. [Brief description of the drawings]

[0029] [Figure 1] FIG. 1 is an exploded isometric view of a hand tool type vernier caliper that uses an electromagnetic induction encoder including a detector and a scale. [Diagram 2] FIG. 2 is a plan view of a prior art embodiment of a detector that can be used in an electromagnetic induction encoder. [Diagram 3] FIG. 3 is an isometric view generally corresponding to FIG. 2 of a prior art embodiment of the end of the magnetic field generating coil of the detector, more clearly illustrating the relative arrangement of the magnetic field generating extension and the conductive receiving loop at the detector. [Figure 4] FIG. 4 is a plan view of a first exemplary embodiment of a detector according to principles disclosed herein and an interchangeable scale pattern usable in an electromagnetic inductive encoder. [Diagram 5]FIG. 5 is an isometric view of the first exemplary embodiment, generally corresponding to FIG. 4, and more clearly illustrating the relative arrangement of the magnetic field generating extension and the conductive receiving loop at the detection portion. [Figure 6] FIG. 6 is an isometric view of a second exemplary embodiment of a detector according to principles disclosed herein and an interchangeable scale pattern usable in an electromagnetic inductive encoder. [Figure 7] FIG. 7 is an isometric view of a third exemplary embodiment according to the principles disclosed herein and an compatible scale pattern that can be used in an electromagnetic inductive encoder. [Figure 8] FIG. 8 is a plan view of a fourth exemplary embodiment of a detector according to principles disclosed herein and an interchangeable scale pattern usable in an electromagnetic inductive encoder. [Figure 9] FIG. 9 is a block diagram illustrating one exemplary implementation of components of a measurement system including an electromagnetic inductive encoder. [Figure 10] FIG. 10 is an isometric view of a portion of the detector of FIG. 5 showing a portion of two sense windings including a first embodiment of a signal connection arrangement that mitigates certain stray signal errors in accordance with the principles disclosed herein. [Figure 11] FIG. 11 is an isometric view similar to FIG. 10 showing a portion of two sense windings including a second embodiment of a signal connection arrangement that mitigates or eliminates certain stray signal errors in accordance with the principles disclosed herein. [Figure 12] FIG. 12 is an isometric view similar to FIG. 11 showing a portion of two sense windings including a third embodiment of a signal connection arrangement that mitigates or eliminates certain stray signal errors in accordance with the principles disclosed herein. [Figure 13] FIG. 13 is an isometric view similar to FIG. 11 showing a portion of two sense windings including a fourth embodiment of a signal connection arrangement that mitigates or eliminates certain stray signal errors in accordance with the principles disclosed herein. [Figure 14]FIG. 14 is an isometric view of a portion of the detector portion of FIG. 7 showing a portion of two sense windings including a fifth embodiment of a signal connection arrangement similar to the fourth embodiment shown in FIG. 13 that mitigates or eliminates certain stray signal errors in accordance with the principles disclosed herein. [Figure 15] FIG. 15 is an isometric view of a portion of the detector of FIG. 6 showing a portion of two sense windings including a sixth embodiment of a signal connection arrangement that mitigates or eliminates certain stray signal errors in accordance with the principles disclosed herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] FIG. 1 is an exploded isometric view of a hand tool type caliper 100 that may use an electromagnetic induction encoder including a known detector 167 and scale pattern 180 or a novel detector 167 and scale pattern 180 in accordance with the principles disclosed herein. In the illustrated embodiment, the caliper 100 includes a scale member 102 having a spar of generally rectangular cross section that includes a scale 170, and a slider assembly 120. In various embodiments, the scale 170 may extend along a measurement axis direction MA, which corresponds to the x-axis direction, and may include a signal modulation scale pattern 180. A cover layer 172 (e.g., 100 μm thick) of known type may cover the scale 170. Jaws 108 and 110 near a first end of the scale member 102 and movable jaws 116 and 118 on the slider assembly 120 are used to measure the dimensions of an object in a known manner. The slider assembly 120 may optionally include a depth bar 126 that is received in a depth bar groove 152 beneath the scale member 102 by end stops 154. A depth bar measuring end 128 may extend into the hole to measure its depth. A cover 139 of the slider assembly 120 may include an on / off switch 134, a set zero switch 136, and a measurement result display 138. A base 140 of the slider assembly 120 includes a guide edge 142 that contacts a side edge 146 of the scale member 102, and a screw 147 biases a resilient pressure bar 148 against an opposing edge of the scale member 102 to ensure proper alignment for measurement and movement of the readhead portion 164 relative to the scale 170.

[0031] A pick-off assembly 160 mounted on the base 140 holds a read head portion 164 which in this embodiment includes a detection portion 167 including a magnetic field generating coil portion and a group of sensing elements (e.g., collectively magnetic field generating and sensing windings) arranged along a measurement axis direction MA, and a multi-layer circuit element 162 (e.g., a printed circuit board or PCB) carrying a signal processing portion (e.g., control circuitry) 166. To prevent contamination of the circuitry and connections, an elastic seal 163 may be compressed between the cover 139 and the multi-layer circuit element 162. The detection portion 167 may be covered by an insulating coating.

[0032] In one particular illustrative example, the detector portion 167 is disposed parallel to and facing the scale 170, and a front or surface of the detector portion 167 facing the scale 170 may be spaced apart from the scale 170 (and / or the signal modulation scale pattern 180) along the depth (Z) direction by a gap of about 0.5 mm. The readhead portion 164 and the scale 170 together may form a transducer as part of an electromagnetic inductive encoder. In one embodiment, the transducer may be an eddy current or induction type transducer that operates by generating a change in a magnetic field. As will be explained in more detail below, the change in the magnetic field induces eddy currents, known as eddy currents, in some of the signal modulating elements of the signal modulating scale pattern 180 that are placed within that magnetic field. It will be appreciated that the caliper 100 shown in FIG. 1 is one of a variety of applications that typically implement electromagnetic inductive encoders that have evolved over the years to provide a relatively optimized combination of compact size, low power operation (e.g., for extended battery life), high resolution and precision measurement, low cost, robustness to dirt, etc. Any of these factors and / or even slight improvements in the signal-to-noise ratio (S / N) achievable in a position encoder are highly desirable but difficult to achieve, particularly in light of the design constraints imposed to achieve commercial success in a variety of applications. The principles disclosed in the following description provide improvements in some of these elements, particularly in terms of cost-effectiveness and miniaturization.

[0033] Figures 2 and 3 are plan and isometric views, respectively, of known prior art implementations of a detector 267 and a scale pattern 180 that may be used as the detector 167 and signal modulating scale pattern 180 in an electromagnetic inductive encoder such as that shown in Figure 1. Only certain features of Figures 2 and 3 are described in detail below to provide appropriate background and explanation applicable to an understanding of certain similar features and operation of novel electromagnetic inductive encoders and detectors, which are described in detail below with reference to Figures 4-9. A more detailed description useful in understanding the embodiments shown in Figures 2 and 3 is provided in commonly assigned U.S. Patent No. 10,520,335 (hereinafter the '335 patent), which is incorporated herein by reference in its entirety.

[0034] FIG. 2 is a plan view showing a known prior art implementation of the detector 267 and scale pattern 180. FIG. 2 can be considered to be partly representational and partly schematic. Enlarged portions of the detector 267 and scale pattern 180 are shown at the bottom of FIG. 2. In FIG. 2, the various elements described below are represented by their shapes or contours and are shown superimposed on one another to emphasize certain geometric relationships. It should be understood that various elements may be present on various fabrication layers located in different planes along the z-axis direction, as necessary, to provide various operating gaps and / or insulating layers, as would be apparent to one skilled in the art, based on commonly known design practices and / or as outlined in the following description (e.g., with reference to FIG. 3). In the particular embodiment shown in Fig. 2 and Fig. 3, the extensions EP1 and EP2 of the magnetic field generating coil FGC overlap the conductive receiving loops SEN1 to SEN24 and are therefore made using a set of extension metal layers including at least a first inner metal layer of the multilayer circuit element, and the conductive receiving loops SEN1 to SEN24 are made using a set of receiving loop metal layers of the multilayer circuit element including at least one metal layer closer to the front surface of the detector facing the scale pattern 180 than the first inner metal layer. In relation to the present subject matter, the enlarged cross-sectional view of the detector 267 in Fig. 2 shows the y-axis ends of each of the conductive receiving loops SEN14 to SEN16 overlapping the extensions EP1 and EP2 with dashed lines, indicating that the conductive receiving loops are closer to the front surface of the detector than the extensions. (See also Fig. 3). Meanwhile, in the front view of the detector 267 in Fig. 2, the two ends of each of the conductive receiving loops SEN1 to SEN24 are shown with solid lines only for ease of illustration. It will be understood that throughout the figures of this disclosure, the illustrated x-axis, y-axis, and / or z-axis dimensions of one or more elements may be exaggerated for clarity.

[0035] The illustrated portion of the signal modulating scale pattern 180 includes signal modulating elements SME, shown in dashed outline, which are disposed on the scale 170 (shown in Figure 1). In the embodiment shown in Figure 2, the y-direction ends of most of the signal modulating elements SME are hidden under the first and second extensions EP1 and EP2. It will be appreciated that the scale pattern 180 moves relative to the detection portion 267 during operation, as shown in Figure 1.

[0036] 2, the scale pattern 180 has a nominal scale pattern width dimension NSPWD along a y-axis direction orthogonal to the x-axis and comprises individual signal modulation elements SME arranged periodically (e.g., corresponding to the x-axis direction) along the measurement axis direction MA. However, more generally, the signal modulation scale pattern 180 may include a variety of alternative spatial modulation patterns including individual elements or one or more contiguous pattern elements, provided that the pattern has spatial characteristics that vary as a function of position along the x-axis direction, thereby providing a position-dependent detection signal (also referred to in some embodiments as a detection signal component) resulting at the sensing elements SEN (e.g., SEN14) of the detector portion 267, in accordance with known methods.

[0037] In various implementations, the sensing portion 267 is mounted proximate to the scale pattern 180 and configured to move along a measurement axis direction MA relative to the scale pattern 180. As will be appreciated by those skilled in the art based on the following disclosure, the sensing portion includes a magnetic field generating coil FGC and a plurality of sensing elements SEN that can assume a variety of alternative configurations used in various embodiments in combination with various corresponding signal processing schemes. FIG. 2 shows a single representative set of sensing elements SEN1-SEN24, which in this particular embodiment comprise conductive receiving loops CRL1-CRL24 (alternatively referred to as sensing loop elements or sensing coil elements) connected in series. In this implementation, adjacent loop elements are connected by a configuration of conductors on various layers of a multilayer circuit element (e.g., as connected by interlayer connections (feedthroughs)) and are connected to have opposite winding polarities according to known methods. That is, if a first loop responds to a change in the magnetic field with a sense signal contribution of positive polarity, the adjacent loop responds with a sense signal contribution of negative polarity. In this particular embodiment, the sensing elements are connected in series such that their detection signals or signal contributions are summed, and the "summed" detection signal is output to a signal processor (not shown) at the detection signal output connections SDS1 and SDS2. While FIG. 2 shows a single set of sensing elements to avoid visual confusion, those skilled in the art will appreciate that in various 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 orthogonal signals). Of course, the configurations of sensing elements described herein are illustrative only and not limiting. As an example, individual sensing element loops may, in some embodiments, output individual signals to corresponding signal processors, for example, as disclosed in commonly assigned U.S. Patent Application Publication No. 2018 / 003524. More generally, in various embodiments, various known sensing element configurations may be used in combination with the principles disclosed and claimed herein for use in combination with various known signal modulation scale patterns and signal processing schemes.

[0038] The various sensing elements and the magnetic field generating coil FGC may be fixed onto a substrate (e.g., multi-layer circuit element 162 of FIG. 1). The magnetic field generating coil FGC may be described as surrounding an interior region INTA having a nominal coil region length dimension NCALD along the x-axis direction and a nominal coil region width dimension of about YSEP along the y-axis direction. In various embodiments, the magnetic field generating coil FGC may include a single winding surrounding the interior region INTA. In operation, the magnetic field generating coil FGC generates magnetic flux changes in the interior region INTA in response to a coil drive signal.

[0039] In various embodiments, the magnetic field generating coil FGC may include an input portion INP, a first extension EP1 and a second extension EP2, and an end portion EDP (e.g., implemented as disclosed with reference to FIG. 3). The input portion INP includes a first input connection ICP1 and a second input connection ICP2 that provide a coil drive signal from a signal processing portion (e.g., signal processing portion 166 of FIG. 1 or signal processing portion 966 of FIG. 9, etc.) to the magnetic field generating coil FGC. The first connection ICP1 and the second connection ICP2 may be connected to the signal processing portion via an interlayer connection of a printed circuit board or the like, and in some embodiments, the connections may be shielded using a principle similar to that disclosed below with reference to the end portion EDP. The first extension EP1 and the second extension EP2 each extend along the x-axis direction adjacent or close to a side of the internal region INTA and have a nominal generating trace width dimension NGTWD along the y-axis direction. In the illustrated embodiment, the nominal generated trace width dimension NGTWD is the same for the first extension EP1 and the second extension EP2, although this is not required in all embodiments. The end EDP (implemented, for example, as disclosed with reference to FIG. 3) spans a y-axis separation between the first extension EP1 and the second extension EP2 corresponding to the nominal coil area width dimension YSEP and provides a connection therebetween near the end of the interior region INTA. In the known embodiment shown in FIGS. 2 and 3, the magnetic field generating coil FGC is advantageously configured with a design ratio in which each nominal generated trace width dimension NGTWD may be at least 0.1 times, or 0.15 times, or 0.25 times, the nominal coil area width dimension YSEP and / or at least 25 times the skin depth of the extensions EP1 and EP2 to minimize the impedance of the magnetic field generating coil FGC at a nominal operating frequency defined in response to a detection signal generated in response to a changing magnetic flux. However, despite its usefulness in various known embodiments, it should be understood that this design ratio is not required in the various novel embodiments disclosed herein which may minimize the impedance of the field generating coils FGC by other means.

[0040] The sensing elements SEN1 to SEN24 are arranged along an x-axis direction (e.g., corresponding to a measurement axis direction MA) and are provided on a substrate (e.g., the multilayer circuit element 162 in FIG. 1). In the example of FIG. 2, each of the sensing elements SEN has a nominal sensing element width dimension NSEWD along the y-axis direction, and at least half of the nominal sensing element width dimension NSEWD is included within the nominal coil area width dimension YSEP along the y-axis direction. The sensing elements SEN are configured to provide detection signals in response to local influences on magnetic flux changes provided by adjacent signal modulation sections (e.g., one or more signal modulation elements SME) of the scale pattern 180 of the scale 170. The signal processor (e.g., the signal processor 166 in FIG. 1 or the signal processor 966 in FIG. 9, etc.) may be configured to identify the positions of the sensing elements SEN1 to SEN24 relative to the scale pattern 180 (or the scale 170) based on the detection signal input from the detector 267. In general, the field generating coils FGC and the sensing elements SEN1-SEN24 etc. may operate according to known principles (eg, inductive encoders) as described in the references.

[0041] In various embodiments, the magnetic field generating coils FGC and the sensing elements SEN are insulated from each other. In some embodiments, they are arranged in different metal layers separated by an insulating layer in a multi-layer circuit element, as already described. In the known embodiment illustrated in Figs. 2 and 3, this is the case if the nominal sensing element width dimension NSEWD of at least one sensing element SEN is preferably larger than the nominal coil area width dimension YSEP between the extensions EP1 and EP2 and extends beyond at least one inner edge IE of the extensions EP1 or EP2 by an amount defined as the overlap dimension OD. Furthermore, in various embodiments, the magnetic field generating coils FGC may be advantageously configured such that each nominal generating trace width dimension NGTWD is larger than the corresponding overlap dimension OD. These and other features described above for the known embodiment illustrated in Figs. 2 and 3 are generally selected to optimize the impedance and signal coupling in the detection portion 267 to maximize its signal-to-noise ratio and / or accuracy. However, it should be understood that, despite their usefulness in various known embodiments, these design features are not necessarily required in various new embodiments in accordance with the principles disclosed herein, which may achieve equal or better impedance and signal coupling by other means, as disclosed with reference to Figures 4-8, to obtain equal or better signal-to-noise ratios and / or accuracy.

[0042] 1, in various embodiments, the detector 267 may be included in various types of measurement instruments (e.g., calipers, micrometers, gauges, linear scales, etc.). For example, the detector 267 may be fixed to a slide member and the signal modulation scale pattern 180 may be fixed to a scale member having a measurement axis that coincides with the x-axis direction. In such a configuration, the slide member is movably attached to the scale member and is movable along the measurement axis direction MA in a plane extending along the x-axis and y-axis directions (the z-axis direction is perpendicular to the plane).

[0043] 3 is an isometric "wireframe" view of a prior art embodiment of the ends of the field generating coils of the detector portion, generally corresponding to FIG. 2, more clearly illustrating the relative arrangement of extensions EP1 and EP2, ends EDP of the field generating coil FGC usable in the detector portion 267, and the conductive receiving loop SEN in the detector portion 267. It will be understood that the elements of the detector portion 267 of FIG. 3 may be similar or identical to similarly numbered elements of the detector portion 267 of FIG. 2 and may generally be understood by analogy thereto.

[0044] The detection portion 267 is shown to include a magnetic field generating coil FGC and a plurality of sensing elements SEN1-SEN24 (representative sensing elements SEN17-SEN24 consisting of conductive receiving loops CRL14-CRL24 are shown in FIG. 3). The magnetic field generating coil FGC includes a first extension EP1, a second extension EP2, and an end EDP, and is fixed on a multi-layer circuit element 162 (e.g., the multi-layer circuit element 162 shown in FIG. 1) and nominally surrounds an interior region INTA.

[0045] As already outlined, in various embodiments, the magnetic field generating coil FGC and the sensing element SEN are insulated from each other, for example, by being disposed on different conductive layers of a printed circuit board separated by an intervening insulating layer. In the particular embodiment shown in FIG. 3, the extensions EP1 and EP2 of the magnetic field generating coil FGC are fabricated using a set of extension metal or conductive layers including at least a first internal metal layer of the multilayer circuit element (at Z coordinate Zep in FIG. 3), and the conductive receiving loops SEN1-SEN24 are fabricated using a set of receiving loop metal layers of the multilayer circuit element including two metal layers (at Z coordinate ZseL1 or ZseL2) closer to the front surface (Z coordinate Zfs) of the sensing element facing the scale pattern 180 than the first internal metal layer (Zep). In FIG. 3, the various labeled Z coordinates can be understood to coincide with or identify the respective faces of the various multilayer circuit element layers. In various embodiments, the multilayer circuit element can be fabricated using PCB, thick film hybrid circuit, thin film circuit, or other alternative manufacturing techniques according to known methods. The signal modulating element SME of the scale pattern 180 is present on the surface of the scale 170 (shown in FIG. 1) at Z coordinate Zsme. It will be understood that the scale 170 is separate from the multi-layer circuit element carrying the detection portion 267. As mentioned above, the multi-layer circuit element (detection portion 267) has a front surface (e.g., a front surface of an insulating coating) located at Z coordinate Zfs. There is an operating gap between the scale surface at Z coordinate Zsme and the front surface at Z coordinate Zfs. The detection element SEN comprises interconnected conductive receiving loops made using a set of receiving loop metal layers of the multi-layer circuit element including at least one metal layer at Z coordinate ZseL1 or ZseL2. The conductive receiving loops may be connected between layers (at Z coordinates ZseL1 and ZseL2) using a conductive inter-layer connection of known type, typically via an insulating layer separating the metal layers according to known methods, so that the conductive portions of the conductive receiving loops may cross each other while connecting the signal contributions of the detection elements in series and providing the polarity of the respective signal contributions, as will be explained more below.

[0046] In the particular embodiment shown in FIG. 3, the first extension EP1 and the second extension EP2 each extend along the x-axis direction and are nominally located at an extension z distance EPZD=(Zep-Zfs) along a z-axis direction perpendicular to the x-axis direction and y-axis direction from a front surface (Zfs) of the multilayer circuit element of the detector 267 facing the scale pattern 180. In some embodiments, the conductive receiver loop includes a planar trace loop portion formed on each layer (ZseL1 and ZseL2) included in the set of receiver loop metal layers, and an interlayer connection portion including a plated hole connecting the planar trace portion between the respective layers. In the illustrated embodiment, the planar trace portion is fabricated on each layer (ZseL1, ZseL2) closer to the detector front surface (Zfs) than the first internal metal layer (Zep). In some embodiments, at least a portion of the planar trace portion of the conductive receiver loop may be fabricated in the metal layer (Zfs) located in front of the detector, or in the respective layer (ZseL1 or ZseL2) that is the metal layer closest to the front of the detector.

[0047] As outlined above, the end EDP comprises a conductive path spanning a y-axis separation between the first and second extensions EP1 and EP2 corresponding to the nominal coil region width dimension YSEP to provide a connection therebetween near the end of the interior region INTA. In the embodiment shown in FIG. 3, the end EDP includes a shielded end SES present on the respective multilayer circuit element layer having a Z coordinate Zses. The shielded end SES is nominally located a shielded end z-distance SESZD=(Zses-Zfs) from the front surface (Zfs) of the multilayer circuit element of the detector 267, where the shielded end z-distance SESZD is greater than the extension z-distance EPZD. In the particular embodiment shown in Figure 3, the shielded end SES is offset along the x-axis direction from the ends of the extensions EP1 and EP2, with a first connection CNP1 (e.g., consisting of an interlayer connection CNP1A of a multilayer circuit element and a conductive trace CNP1B) connecting the first extension EP1 to a first end of the shielded end SES and a second connection CNP2 (e.g., consisting of an interlayer connection CNP2A of a multilayer circuit element and a conductive trace CNP2B) connecting the second extension EP2 to a second end of the shielded end SES. In an alternative embodiment (not shown in Figure 3), the shielded end SES may not be significantly offset along the x-axis direction from the ends of the extensions EP1, EP2, and the conductive traces CNP1B, CNP2B may be omitted. That is, the interlayer connection CNP1A of the multilayer circuit element may connect the first extension EP1 to a first end of the “non-offset” shielded end SES, and the interlayer connection CNP2A of the multilayer circuit element may connect the second extension EP2 to a second end of the “non-offset” shielded end SES.

[0048] In any of the embodiments of the edge EDP described above, the detection portion 267 further includes a conductive shielding region CSR (e.g., a conductive planar region represented by the somewhat arbitrarily placed dashed "edge" line in FIG. 3) extending along the x-axis direction and the y-axis direction, nominally located on the surface of the respective multilayer circuit element layer having a Z coordinate Zcsr, and located at a shielding region z distance SRZD=(Zcsr-Zfs) from the front surface of the multilayer circuit element of the detection portion 267. In various embodiments, the shielding region z distance SRZD is less than the shielded edge z distance SESZD, and the conductive shielding region CSR is located between at least a portion of the shielded edge SES and the front surface (Zfs) of the multilayer circuit element of the detection portion 267. The conductive shielding region CSR may include a portion of an extensive ground plane layer within the multilayer circuit element of the detection portion 267, or in some embodiments may include a discrete region. The conductive shielding region CSR may include clearance holes such that the first connection portion CNP1 and the second connection portion CNP2 (eg, interlayer connections of a multi-layer circuit element) are separated or insulated from the conductive shielding region CSR.

[0049] As taught in the '355 patent, prior to the use of shielded ends according to the principles described above with reference to FIG. 3, magnetic field components generated by the ends of the field generating coils (e.g., ends extending along the y-axis direction) caused error components in the detection signals of the closest sensing elements, so-called "end effects." Attempts have been made to mitigate this end effect by using "tapered end structures" of the sensing section and / or by spacing the ends of the field generating coils farther away from the end sensing elements. However, these approaches undesirably reduce the signal strength, increase the x-axis dimension of the sensing section, or both. In contrast, the shielded end configuration described above with reference to FIG. 3 tends to reduce and / or prevent the field components generated by the ends from reaching the signal modulating element SME. Thus, the magnetic field components coupled to the closest sensing elements are smaller and / or approximately constant, regardless of the position on the scale, thus substantially mitigating the end effects. The '335 patent further summarizes that the shielded end configuration as outlined above with reference to FIG. 3 uses conductive shielding region(s) CSR to reduce the effect of the shielded end SES on the sensing element SEN (e.g., associated with changing magnetic flux), which may allow for a shorter overall x-axis dimension for the field generating coil FGC (or detection portion 267) where the end EDP does not need to be positioned as far away as possible from the sensing element SEN so as not to affect the detection signal generated in response to changing magnetic flux, etc.

[0050] However, while the '335 patent (commonly assigned with the present application) suggests that the ends of the field generating coil FGC need not be located farther from the sensing elements SEN than the prior art configurations discussed above, it nevertheless discloses and teaches only configurations that include some separation between the ends EDP of the field generating coil FGC and the nearest sensing elements SEN. In particular, the '335 patent does not recognize or suggest that the ends EDP or shielded ends SES may be located proximate to any sensing elements SEN. In contrast, the inventors have discovered configurations in which the ends EDP or shielded ends SES are advantageously located proximate to and / or overlapping the sensing elements SEN. Or, stated differently, the inventors have discovered configurations in which the field generating coil FGC is substantially shorter than previously known configurations, and in which a plurality of sensing elements SEN advantageously extend beyond the ends EDP or shielded ends SES of the field generating coil FGC along the x-axis direction. Various features and alternatives that may be used in such configurations are disclosed below with reference to FIGS. 4-8.

[0051] 4 and 5 are plan and isometric views, respectively, of a first embodiment of a detector 467 and a compatible scale pattern 180 according to the principles disclosed and claimed herein, which can be used as the detector 167 and the signal modulation scale pattern 180 in an electromagnetic induction encoder as shown in FIG. 1, etc. The detector 467 has certain features and components similar to the detector 267 of FIG. 2 and FIG. 3. In particular, elements designated with similar reference numbers (e.g., similar names or numbers or numeric "suffixes") in FIG. 4 and FIG. 2, or in FIG. 5 and FIG. 3, or elements that are otherwise apparently similar in the various figures, may be understood to be similar elements and to operate similarly, except as otherwise noted below. Only certain features of FIG. 4 and FIG. 5 are described in detail below, in order that the description may highlight novel features and / or advantages in accordance with the principles disclosed and claimed herein, and the figures may be otherwise understood by one of ordinary skill in the art by analogy with other figures and descriptions contained herein, or other figures and descriptions contained in the incorporated references.

[0052] FIG. 4 is a plan view showing a first exemplary embodiment of a detector 467 and a compatible scale pattern 180 that can be used in an electromagnetic induction encoder. FIG. 4 can be considered to be partly representational and partly schematic. As previously indicated, it will be understood that throughout the drawings of this disclosure, the illustrated x-axis, y-axis, and / or z-axis dimensions of one or more elements may be exaggerated for clarity. Enlarged portions of the detector 467 and scale pattern 180 are shown at the bottom of FIG. 4. In FIG. 4, the various elements described below are represented by their shapes or contours and are shown superimposed on one another to emphasize certain geometric relationships. It will be understood that various elements may be present on various processing layers located in different planes along the z-axis direction, as necessary, to provide various operating gaps and / or insulating layers, based on commonly known design practices and / or as outlined in the following description and / or as outlined in the following description (e.g., with reference to FIG. 5), as will be apparent to one of ordinary skill in the art.

[0053] As shown in Figures 4 and 5, the signal modulation scale pattern 180 includes a first pattern track FPT having a pattern track width dimension PTDY along a y-axis direction orthogonal to the x-axis direction. The first pattern track includes signal modulation elements SME arranged to provide a spatially varying characteristic that varies as a periodic function of position along the x-axis direction. The detection portion 467 is mounted proximate to the first pattern track FPT and configured to move relative to the first pattern track FPT along the measurement axis direction MA. The detection portion 467 includes a multi-layer circuit element (e.g., as previously outlined herein) having a front surface that faces the scale carrying the scale pattern 180 during normal operation. The detection portion 467 includes a magnetic field generating coil FGC fixed to the multi-layer circuit element, at least one first track shield end arrangement SEC (FT), and a plurality of sensing elements SEN, as described in more detail below.

[0054] As shown in Fig. 4, the magnetic field generating coil FGC is composed of an input section INP including at least two connecting sections ICP1, ICP2 for connecting the magnetic field generating coil to a coil driving signal from a signal processing section (e.g., the signal processing section 166 in Fig. 1 or the signal processing section 966 in Fig. 9), and a first track magnetic field generating coil section FGCP(FT) configured to surround a first track generated magnetic field field GFA(FT) nominally aligned with the first pattern track FPT and generate a first track changing magnetic flux in the first track generated magnetic field field GFA(FT) in response to the coil driving signal. The first track magnetic field generating coil section FGCP(FT) shown in Fig. 4 is fabricated in one or more extension layers EPL of the multi-layer circuit element (e.g., as shown in Fig. 5) and has a first track first side extension section EPS1(FT) and a first track second side extension section EPS2(FT) extending along the x-axis direction adjacent to the first side and second side of the first track generated magnetic field field GFA(FT). The first track first side extension portion EPS1(FT) and the first track second side extension portion EPS2(FT) together extend across or define a first track extension length dimension EPDX along the x-axis direction, and the y-axis separation between the first track first side extension portion EPS1(FT) and the first track second side extension portion EPS2(FT) defines a minimum width dimension GFADY(FT) of the first track generated magnetic field region. The first track magnetic field generating coil section FGCP(FT) further comprises a first track shielded end SES(FT) fabricated in a first track shielded end layer (sometimes referred to as a shielded conductor layer) SESL(FT) of the multilayer circuit element (e.g., as shown in FIG. 5), spanning the y-axis distance between the first track first side extension portion EPS1(FT) and the first track second side extension portion EPS2(FT), and included in an end conductor path ECP connecting the first track first side extension portion EPS1(FT) and the first track second side extension portion EPS2(FT) in the first track magnetic field generating coil section FGCP(FT).

[0055] The first track shield end configuration SEC(FT) is composed of the above-mentioned first track shielded end SES(FT) and the first track conductive shield region CSR(FT) (e.g. as shown in FIG. 5). As will be described in more detail below with reference to FIG. 5, the conductive shield region CSR(FT) is included in the conductive shield region configuration CSRC, extends along the x-axis and y-axis directions, and is made in a first track shield region layer SRL(FT) located between the first track shielded end layer (shielded conductor layer) SESL(FT) and one or more receiving loop layers RLL (e.g. RLL1 and RLL2) of the multilayer circuit element with respect to a position along the z-axis direction that is nominally normal to the front surface FS of the multilayer circuit element.

[0056] As shown in FIG. 4, a plurality of sensing elements SEN (e.g., SEN1-SEN24) have respective conductive receiving loops (e.g., CRL1-CRL24) fabricated in one or more receiving loop layers RLL (e.g., RLL1 and RLL2 as shown in FIG. 5) of a multilayer circuit element, where the conductive receiving loops CRL are distributed along the x-axis direction over a first track sensing element area SEA(FT) nominally aligned with the first pattern track FPT. The sensing elements SEN are configured to provide a sensing signal or a sensing signal contribution in response to a local influence on the first track changing magnetic flux provided by an adjacent signal modulating element SME of the scale pattern 180. The sensing elements SEN are described in further detail below with reference to FIG. 5.

[0057] It will be understood that a signal processing unit (such as, for example, signal processing unit 566 in FIG. 5) may be operably connected (e.g., at connection points ICP1 and ICP2) to the detection unit 467 to provide a coil drive signal, and configured to determine the relative position between the detection unit 467 and the scale pattern 180 based on the detection signal input from the detection unit 467 (e.g., at detection signal output connections SDS1 and SDS2 in FIG. 4, as described in further detail below with reference to signal processing unit 566 in FIG. 5).

[0058] FIG. 5 is an isometric "wireframe" view of the first exemplary embodiment, generally corresponding to FIG. 4, and more clearly illustrating the relative arrangement of the extensions EPS1 and EPS2 generating the magnetic field at the detection portion 467, the shielded end SES, the conductor path ECP of the magnetic field generating coil FGC, and the conductive receiving loop CRL. For clarity of illustration, FIG. 5 shows fewer sensing elements SEN and / or conductive receiving loops CRL than FIG. 4, but these elements may be understood to be similar in FIG. 4 and FIG. 5. FIG. 5 can be considered to be partly representational and partly schematic. The suffix "(FT)" of "first track" used in FIG. 4 has been omitted from the reference numbers / reference characters throughout FIG. 5 for clarity of illustration. However, it will be understood that the elements illustrated in FIG. 5 may be considered, despite this omission, as “first track” elements, and alternatively, as “second track” elements (corresponding to the reference numeral / character suffix “(ST)” and usable in certain embodiments described in more detail below). It will be understood that the elements of detector 467 of FIG. 5 may be similar or identical to similarly numbered elements of detector 467 of FIG. 4 and may be generally understood by analogy thereto. Accordingly, only certain features of FIG. 5 are described in detail below as necessary to highlight novel features and / or advantages in accordance with the principles disclosed and claimed herein.

[0059] As shown in FIG. 5, the signal modulation scale pattern 180 includes a first pattern track FPT having the characteristics and dimensions already outlined. The detection portion 467 is mounted proximate to the first pattern track FPT and configured for relative displacement along the measurement axis direction MA with respect to the first pattern track FPT. It will be understood that the detection portion 467 includes a multi-layer circuit element represented by its conductive layers as described below, separated by insulating layers according to known principles, for example as already outlined herein. It will be understood that the multi-layer circuit element has a front surface facing the scale carrying the scale pattern 180 during normal operation. The detection portion 467 includes a magnetic field generating coil FGC fixed to the multi-layer circuit element, at least one first track shielding end arrangement SEC, and a plurality of sensing elements SEN with conductive receiving loops CRL, as will be described in more detail below.

[0060] As shown in FIG. 5, the magnetic field generating coil FGC comprises an input section INP and a first track magnetic field generating coil section FGCP configured to surround a first track generating magnetic field area GFA nominally aligned with the first pattern track FPT and to generate a first track changing magnetic flux in the first track generating magnetic field area GFA in response to a coil drive signal from the signal processing section 566.

[0061] In the particular embodiment shown in FIG. 5, in order to supply the coil drive signal from the signal processing unit 566, the input unit INP has two input connections ICP1A, ICP2A which are respectively connected to input connections ICP1B and ICP2B which connect the magnetic field generating coil FGC to the signal processing unit 566.

[0062] The first track magnetic field generating coil section FGCP shown in Fig. 5 has a first track first side extension EPS1 and a first track second side extension EPS2 fabricated in one or more extension layers EPL of a multi-layer circuit element. The layer EPL and other layers described herein are indicated in Fig. 5 by reference numbers and dashed lines corresponding to exemplary planes for such layers. The first track first side extension EPS1 and the first track second side extension EPS2 extend along the x-axis direction proximate the first side S1 and the second side S2 of the first track generated magnetic field field GFA. The first track first side extension portion EPS1 and the first track second side extension portion EPS2 together extend across or define a first track extension length dimension EPDX along the x-axis direction, and the y-axis separation between the first track first side extension portion EPS1 and the first track second side extension portion EPS2 defines a nominal width dimension GFADY of the first track generated magnetic field region.

[0063] The first track magnetic field generating coil section FGCP further comprises a first track shielded end SES fabricated in a first track shielded end layer (sometimes referred to as a shielded conductor layer) SESL of the multilayer circuit element, spanning the y-axis distance between the first track first side extension section EPS1 and the first track second side extension section EPS2, and included in an end conductor path ECP connecting the first track first side extension section EPS1 and the first track second side extension section EPS2 in the first track magnetic field generating coil section FGCP. In the particular embodiment shown in Fig. 5, the end conductor path ECP comprises a first track shielded end SES, end conductor path sections ECP1B and ECP2B, and two end conductor path sections ECP1A and ECP2A that are interlayer connection elements connected to the end conductor path sections ECP1B and ECP2B, respectively, for connecting the first track first side extension EPS1 and the first track second side extension EPS2 via the shielded end SES of the first track magnetic field generating coil section FGCP. In the particular embodiment shown in Fig. 5, the shielded end SES is offset along the x-axis direction from the ends of the extensions EPS1 and EPS2, which necessitates the use of the end conductor path sections ECP1B and ECP2B in the end conductor path ECP. In alternative embodiments (not shown in FIG. 5 ) (particularly alternative configurations in which the conductive shielding area is expanded along the x-axis direction, as indicated by arrows A1 or A2 in FIG. 5 ), the shielded end SES need not be significantly offset along the x-axis direction from the ends of the extensions EPS1 and EPS2. In such alternative embodiments, the end conductor path portion ECP1B and the end conductor path portion ECP2B may be omitted. That is, the interlayer connection element ECP1A may connect the first side extension EPS1 to a first end of the “non-offset” shielded end SES, and the interlayer connection element ECP2A may connect the second side extension EPS2 to a second end of the “non-offset” shielded end SES. As shown in FIG. 5, two end conductor path portions or interlayer connection elements ECP1A, ECP2A extend along the z-axis direction, pass through the conductive shielding area CSR using an insulated hole (void) INSV, and connect the first track first side extension portion EPS1 and the first track second side extension portion EPS2 through the shielded end portion SES via the end conductor path ECP.In various embodiments in which various configurations of conductive shielding regions CSR and / or end conductor paths ECP can be used, each connection between a first track extension, such as EPS1 or EPS2, and a first track shielded end SES includes an interlayer connection element (e.g., a PCB interlayer connection element) similar to those outlined above.

[0064] In the particular embodiment shown in Fig. 5, the first track shielding end configuration SEC comprises the first track shielded end SES described above and the first track conductive shielding region CSR, which in one embodiment may be configured substantially as illustrated by the solid lines in the first track shielding end configuration SEC in Fig. 5. As shown in Fig. 5, the conductive shielding region CSR may be considered to be included in the conductive shielding region configuration CSRC (which may include additional conductive shielding regions CSR' in some embodiments). The conductive shielding region CSR is generally made in a first track shielding region layer SRL that extends to various extents along the x-axis direction and the y-axis direction in various embodiments and is located between the first track shielded end layer (shielded conductor layer) SESL and one or more receiving loop layers RLL (e.g. RLL1 and RLL2) of the multilayer circuit element with respect to the position along the z-axis direction.

[0065] As shown in Figures 4 and 5, a plurality of sensing elements SEN (e.g., SEN1-SEN24) have respective conductive receiving loops (e.g., CRL1-CRL24) fabricated in one or more receiving loop layers RLL (e.g., RLL1 and RLL2) of a multilayer circuit element, and the conductive receiving loops CRL are distributed along the x-axis direction over a first track sensing element area SEA (having corresponding dimensions SEADX and SEADY) nominally aligned with the first pattern track FPT. The sensing elements SEN are configured to provide a detection signal or detection signal contribution in response to a local influence on the first track changing magnetic flux provided by an adjacent signal modulation element SME of the scale pattern 180. In the particular embodiment illustrated in Figure 5, the conductive receiving loops CRL do not overlap the first track first side extension EPS1 and the first track second side extension EPS2. Thus, in contrast to the layers of detection portion 267, in some embodiments of detection portion 467, the extension portion layer EPL and at least one receiving loop layer RLL1 or RLL2 may be the same layer of a multi-layer circuit element, and at least one of the first track extension portions EPS1 and EPS2 and at least a portion of the conductive receiving loop CRL may be fabricated within that same layer.

[0066] As already outlined when describing the particular input section INP shown in Fig. 5, the signal processing section 566 may be operatively connected to the detection section 467, for example via two input connections ICP1A, ICP2A respectively connected to input connections ICP1B, ICP2B connecting the field generating coil FGC to the coil drive signal from the signal processing section 566. The signal processing section 566 may further be configured to determine the relative position between the detection section 467 and the scale pattern 180, for example based on the detection signal input from the detection section 467 at the detection signal output connections SDS1 and SDS2, as shown in Fig. 5. In the particular embodiment shown in Fig. 5, the detection signal output connections SDS1 and SDS2 are connected to the signal processing section 566 via interlayer connection elements DSFT1 and DSFT2, respectively, which utilize insulated holes INSV to connect to the signal processing section 566 through the conductive shielding area CSR'. It will be appreciated that the connections and conductive shielding region CSR' used in the input portion INP are similar to the end conductor portions and shielded ends SES and conductive shielding region CSR used in the first track shielding end configuration SEC of Figure 5. It will be appreciated that in various embodiments it will be advantageous to utilize principles similar to those disclosed with reference to the first track shielding end configuration SEC for shielding the various connections of the input portion INP (and, if desired, the circuitry and connections associated with the signal processing portion 566).

[0067] 4 and 5 show one representative set of sensing elements SEN1-SEN24 with conductive receiving loops CRL1-CRL24 connected in series. In this particular embodiment, adjacent loop elements are connected by an arrangement of conductors on the two conductive receiving loop layers RLL1, RLL2, as already outlined with reference to the detection unit 267. The sensing elements SEN (conductive receiving loops CRL) are connected in series such that their detection signals or signal contributions are added, and a "added" detection signal is output to the signal processing unit 566 at the detection signal output connections SDS1 and SDS2. Although FIGS. 4 and 5 show a single set of sensing elements SEN to avoid visual confusion, those skilled in the art will appreciate that in various implementations it may be advantageous to configure the detection unit to provide one or more additional sets of sensing elements at different spatial phase positions (e.g. to provide orthogonal signals) and connect them in a similar manner to the signal processing unit 566. It will therefore be appreciated that the configurations of sensing elements SEN described herein are merely exemplary and not limiting. As an example, each sensing element loop may, in some embodiments, output a separate signal to a corresponding signal processor, as disclosed, for example, in commonly assigned U.S. Patent Application Publication No. 2018 / 003524. More generally, in various embodiments, a variety of known sensing element configurations may be used in combination with the principles disclosed and claimed herein for use in combination with a variety of known signal modulation scale patterns and signal processing schemes.

[0068] The embodiment shown in Figures 4 and 5 includes the following important and noteworthy features which differ from those used in the sensing portions of known prior art electromagnetic inductive encoders:

[0069] First, the first track sensing element area SEA(FT) extends across a first track sensing element area length dimension SEADX(FT) along the x-axis direction and a first track sensing element area width dimension SEADY(FT) along the y-axis direction, and the first track sensing element area length dimension SEADX(FT) along the x-axis direction is greater than the first track extension length dimension EPDX(FT). Conversely, the first track extension length dimension EPDX(FT) may be significantly less than the first track sensing element area length dimension SEADX(FT) along the x-axis direction. Surprisingly, the inventors have determined that such a configuration may enable unexpected trade-offs and advantages related to signal level, signal-to-noise ratio and / or accuracy, and manufacturing costs in an electromagnetic induction encoder in accordance with the principles disclosed herein. For example, it should be appreciated that in such a case, the sensing portion 467 may be significantly shorter than known sensing portions, and the relatively short first track first side extension EPS1 and first track second side extension EPS2 may also provide significantly reduced resistance to the relatively short magnetic field generating configuration FGC, which may have an inherently lower impedance compared to known magnetic field generating configurations. As a result, unexpectedly high signal levels may be achieved in a practical manner, while adverse end effects may be relatively reduced, various constraints on known magnetic field generating configurations and sensing portion configurations taught in such prior art may be relaxed or eliminated, and manufacturing costs may be reduced, as outlined below.

[0070] In some such embodiments, as shown in FIG. 5, the first track sensing element area length dimension SEADX along the x-axis direction may extend beyond the first track extension length dimension EPDX at each end by at least a dimension SE. In some embodiments, the inventors have discovered that it may be advantageous for accuracy if the dimension SE is at least K times the nominal width dimension GFADY of the first track generated magnetic field area, where K is a number that is at least 1. In some such embodiments, it may be more advantageous for accuracy if K is at least 2. As shown in FIG. 5, the signal modulating elements of the first pattern track may be arranged corresponding to a spatial wavelength WL along the x-axis direction. According to an additional design principle discovered by the inventors, in some embodiments where K is at least 1, it may be advantageous for accuracy if the dimension SE is also at least as large as WL. In some such embodiments, it may be more advantageous for accuracy if the dimension SE is even larger, at least 2*WL.

[0071] Second, as best shown in FIG. 5 with reference to the first track shielded end SES and the conductive receiving loop CRL, for example, the first track shielded end SES is configured such that its z-axis projection along the z-axis direction toward the receiving loop layer at least partially overlaps the conductive receiving loop CRL in the first track sensing element area SEA. It will be appreciated that this feature is related to the first track extension length dimension EPDX being less than the first track sensing element area length dimension SEADX along the x-axis direction, as discussed above. However, it is notable that this configuration feature is explicitly avoided in the teachings of the '335 patent and in known prior art detectors, thus imposing undesirable design limitations that impact the cost, size and / or accuracy that may be achieved with such detectors.

[0072] Third, the inventors have found that it is advantageous in various embodiments (or possibly all embodiments) (e.g., to facilitate precision, robustness, and / or low-cost manufacturing) if the first track conductive shielding region CSR is configured in its first track shielding region layer SRL to block at least half or more of the area of ​​the z-axis projection ZPROJ of the first track shielding end SES that overlaps with the conductive receiving loop CRL in the first track sensing element region SEA, between the first track shielding end SES and the conductive receiving loop CRL in the first track sensing element region SEA. It will be appreciated that the conductive shielding region CSR shown in solid outline in FIG. 5 is configured to block all of the area of ​​the z-axis projection ZPROJ of the first track shielding end SES that overlaps with the conductive receiving loop CRL of the first track sensing element region SEA (except for the insulated hole INSV that extends generally along the z-axis direction and surrounds the conductive interlayer connection that passes through the at least one first track conductive shielding region CSR). This may be advantageous in various embodiments. However, in some embodiments, significant and substantial benefits to accuracy may be obtained if the illustrated first track conductive shielding region CSR is scaled down along the x-axis direction as indicated by arrow A3, where the first track conductive shielding region CSR would be configured to shield at least half or more of the area of ​​the z-axis projection ZPROJ of the first track shielded end SES. In any case, known detector embodiments (e.g., as taught in the '335 patent) do not recognize such a configuration of the conductive shielding region CSR as a significant, useful, or applicable feature, since they utilize a fundamentally different configuration or positional relationship between the first track shielded end SES and the conductive receiving loop CRL within the first track sense element region SEA.

[0073] It will be appreciated that the function of the first track conductive shielding region CSR etc. is to mitigate or eliminate error-causing "end effect" interactions between magnetic fields generating in the vicinity of the first track shielded end SES and the sensing elements SEN and / or signal modulation elements SME in the first track sensing element region SEA. The description of the configuration of the conductive shielding region CSR relative to a hypothetical projection of one or more of these elements is merely a practical way of defining advantageous embodiments that achieve the desired mitigation or elimination of such error-causing "end effect" interactions.

[0074] The inventors have discovered that in some embodiments, the first track conductive shielding region CSR, constructed according to the principles described above, may be advantageously further constructed according to an additional design principle or design aspect, whereby the first track conductive shielding region CSR is advantageously further constructed to shield at least half or more of the area of ​​the projection along the z-axis direction of the conductive receiving loops CRL distributed at the end of the first track sensing element region SEA located outside the end of the first track extension dimension EPDX corresponding to the location of the first track shielded end SES. For further explanation and not by way of limitation, in the embodiment shown in FIG. 5, this description corresponds approximately to the projection along the z-axis direction of the conductive receiving loops CRL distributed along the dimension SE in the first track sensing element region SEA. It will be appreciated that the first track conductive shielding region CSR, shown in solid outline in FIG. 5, is constructed according to this additional design principle.

[0075] The inventors have discovered that in some embodiments, the first track conductive shielding region CSR, configured according to the principles described above, may be advantageously further configured according to additional design principles or aspects to shield all areas of the projection along the z-axis of at least one conductive receiving loop CRL that is distributed in a portion of the first track sensing element region SEA located inside the end of the first track extension dimension EPDX corresponding to the location of the first track shielded end SES. For further explanation and not by way of limitation, in the embodiment shown in FIG. 5, this description corresponds approximately to the projection along the z-axis of the conductive receiving loop CRL 14, and corresponds approximately to the expansion of the illustrated first track conductive shielding region CSR along the x-axis, as indicated by the arrow A1.

[0076] The inventors have found that in some embodiments, it is advantageous for a first track conductive shielding region CSR constructed according to the above principles to be further configured to block all of the areas of the projections along the z-axis direction of all conductive receiving loops CRL distributed in the first track sensing element region SEA, except when at least one first track conductive shielding region includes an insulated hole extending generally along the z-axis direction and surrounding a conductive interlayer connection passing through the at least one first track conductive shielding region. For further explanation and not by way of limitation, in the embodiment shown in Figure 5, the illustrated first track conductive shielding region CSR is expanded along the x-axis direction as indicated by the arrow A2, which corresponds approximately to merging the conductive shielding region CSR' with the conductive shielding region CSR in the conductive shielding region configuration CSRC and / or in the conductive shielding region configuration CSRC.

[0077] It should be understood that the design principles and embodiments disclosed above with reference to Figures 4 and 5 differ in several important respects from the prior art embodiments taught in the '335 patent and illustrated in Figures 2 and 3.

[0078] According to the first principle disclosed above, the first track detector element area SEA(FT) extends across a first track detector element area length dimension SEADX(FT) along the x-axis direction and a first track detector element area width dimension SEADY(FT) along the y-axis direction, the first track detector element area length dimension SEADX(FT) being greater than the first track extension length dimension EPDX(FT). The dimension in FIG. 2 which is similar to the first track detector element area length dimension SEADX(FT) is conveniently labeled SEADXana (the suffix "ana" signifying similar). The dimension in FIG. 2 which is similar to the first track extension length dimension EPDX(FT) is conveniently labeled EPDXana. In contrast to the above design principle, it can be seen that the '335 patent teaches the opposite. That is, as shown in FIG. 2, the analog of the first track detector element area length dimension SEADXana along the x-axis direction is significantly shorter than the analog of the first track extension length dimension EPDXana. 2. Or, stated another way, the first track extension length dimension EPDX(FT) shown in FIG. 4 is significantly shorter (eg, half the length or less) than its analog EPDXana shown in FIG.

[0079] According to the second principle disclosed above, the first track shielded end SES(FT) shown in FIG. 4 is configured such that its z-axis projection along the z-axis direction at least partially overlaps the conductive receiving loop CRL in the first track sensing element area SEA(FT) toward the receiving loop layer (e.g., as shown and described in more detail with reference to the first track shielded end SES shown in FIG. 5). Features similar to the first track shielded end SES(FT) of FIG. 2 and FIG. 3 are conveniently denoted as SESana (the suffix "ana" means similar). In contrast to the above design principle, it can be seen that the '335 patent teaches the opposite. That is, as shown in FIG. 2 and FIG. 3, the first track shielded end analog SESana is intentionally located significantly away from the nearest end conductive receiving loop CRL and is configured such that its z-axis projection along the z-axis direction toward the receiving loop layer is prohibited from overlapping (i.e., significantly away from) the conductive receiving loop CRL of the corresponding sensing element area of ​​FIG. 2 and FIG. 3. This limitation precludes several features and advantages associated with the electromagnetic inductive encoder and detector design principles disclosed and claimed herein as taught in the '335 patent and illustrated in Figures 2 and 3.

[0080] According to the third principle disclosed above, the first track conductive shielding region CSR(FT) is configured in its first track shielding region layer SRL to be interposed between the first track shielded end SES(FT) in the first track sensing element region SEA(FT) and the conductive receiving loop CRL, and to block at least half or more of the area of ​​the z-axis projection of the first track shielded end SES(FT) that overlaps with the conductive receiving loop CRL in the first track sensing element region SEA(FT) (for example, as shown and described in detail with reference to the conductive shielding region CSR and conductive shielding region configuration CSRC shown in FIG. 5). Features in FIG. 3 that are similar to the conductive shielding region CSR are similarly labeled CSR. In contrast to the design principles outlined above, it can be seen in FIG. 3 that the '335 patent teaches that the conductive shielding region CSR need not be configured to interpose between the first track shielded end SES and the corresponding conductive receiving loop CRL in the first track sensing element region in its first track shielding region layer (located at Z position Zcsr in FIG. 3). It can also be seen with reference to FIG. 3 that in contrast to the design principles outlined above, the '335 patent further teaches that the conductive shielding region CSR need not be configured to block at least half or more of the area of ​​the z-axis projection of the first track shielded end SES that overlaps with the conductive receiving loop CRL in the first track sensing element region. That is, as shown in FIG. 3, the analog of the first track shielded end SESana is intentionally positioned significantly away from the nearest end conductive receiving loop CRL, as well as its corresponding conductive shielding region CSR. As a result, their z-projections along the z-direction are prohibited from overlapping (i.e., significantly spaced apart) with the conductive receive loops CRL in their corresponding sensing element regions of Figure 3. Furthermore, the illustrated conductive shielding regions CSR of Figure 3 are similarly significantly spaced apart from the conductive receive loops CRL in their corresponding sensing element regions.

[0081] Thus, in accordance with the foregoing discussion, the teachings of the '335 patent (e.g., as illustrated in Figures 2 and 3) are incompatible with the design principles of the electromagnetic induction encoder and detector disclosed and claimed herein, because the '335 patent is directed to detector configurations that include certain fundamentally different element relationships than detectors constructed in accordance with the principles and claims disclosed herein. If there is an incidental reference in the '335 patent to a configuration that may satisfy the unique design principles disclosed herein, it is an accidental occurrence and is not an intentional teaching. Such a reference would not be understood by one of ordinary skill in the art as a particularly advantageous, desirable, or applicable design principle or feature that suggests the various design principles, features, and synergistic combinations thereof disclosed and claimed herein.

[0082] FIG. 6 is an isometric "wireframe" view showing a second exemplary embodiment of a detector 667 according to the principles disclosed herein and a compatible scale pattern 680 usable in an electromagnetic inductive encoder. The detector 667 has certain features and components similar to the detector 467 of FIGS. 4 and 5. In particular, elements designated with similar reference numbers (e.g., similar names or numbers or numeric "suffixes") in FIG. 6 and in FIGS. 4 and 5, or otherwise apparently similar elements in the various figures, may be understood to be similar elements and to operate similarly, except as otherwise noted below. Only certain features of FIG. 6 are described in detail below, such description being intended to highlight novel features and / or advantages in accordance with the principles disclosed and claimed herein, and the drawing may otherwise be understood by one of ordinary skill in the art by analogy with the other drawings and descriptions contained herein, or other drawings and descriptions contained in the incorporated references. The detector 667 and compatible scale pattern 680 provide a further advantage in that it provides more robust signal accuracy and / or signal strength compared to previously described embodiments.

[0083] Generally speaking, the main differences between the embodiment of FIG. 6 and the embodiments of FIGS. The scale pattern 680 further includes, in addition to the first pattern track FPT, a second pattern track SPT that is similar to the first pattern track FPT; In addition to a first track detector element (generally identified by the suffix "(FT)" for "first track"), the detector 667 further includes a second track detector element (generally identified by the suffix "(ST)") that is similar to the first track detector element described above.

[0084] 6, the signal modulation scale pattern 680 includes a first pattern track FPT, which will be understood to have the characteristics and dimensions outlined above, and a second pattern track SPT similar to the first pattern track FPT. The first pattern track FPT and the second pattern track SPT include the same type of signal modulation elements SME arranged according to the same spatial period or wavelength WL along the x-axis direction in the first pattern track FPT and the second pattern track SPT, respectively, and the signal modulation elements SME in the second pattern track SPT are offset along the measurement axis direction by a nominal scale track offset of about WL / 2 relative to the signal modulation elements in the first pattern track.

[0085] The detection section 667 is mounted adjacent to the first pattern track FPT and the second pattern track SPT and is configured to be displaced relative thereto along the measurement axis direction MA. It will be understood that the detection section 667 includes a multi-layer circuit element having conductive layers, represented by the various conductive elements illustrated in FIG. 6, as already outlined herein, which are separated by insulating layers according to known principles, as already outlined herein. The detection section 667 comprises a field generating coil FGC fixed to the multi-layer circuit element, at least one first track shielding end arrangement SEC, and a plurality of sensing elements SEN' with conductive receiving loops CRL', as will be described in more detail below.

[0086] As shown in Fig. 6, the magnetic field generating coil FGC comprises an input section INP, a first track magnetic field generating coil section FGCP(FT) and a second track magnetic field generating coil section (ST). The first track magnetic field generating coil section FGCP(FT) is configured to surround a first track generated magnetic field region GFA(FT) nominally aligned with the first pattern track FPT and generate a first track changing magnetic flux in the first track generated magnetic field region GFA(FT) in response to a coil driving signal from the signal processing section. Similarly, the second track magnetic field generating coil section FGCP(ST) is configured to nominally surround a second track generated magnetic field region GFA(ST) nominally aligned with the second pattern track SPT and generate a second track changing magnetic flux in the second track generated magnetic field region GFA(ST) in response to a coil driving signal from the signal processing section.

[0087] In the particular embodiment shown in FIG. 6, as will be understood based on the above description, the input section INP comprises two input connection sections ICP1 and ICP2 which are connected to the magnetic field generating coil FGC via inter-layer connections and which are also connected to the signal processing section.

[0088] The first track magnetic field generating coil section FGCP(FT) shown in FIG. 6 has a first track first side extension EPS1 and a first track second side extension EPS2 fabricated in one or more extension layers of a multi-layer circuit element as outlined above. The first track first side extension EPS1(FT) and the first track second side extension EPS2(FT) extend along the x-axis direction proximate to the first and second sides of the first track generated magnetic field field GFA(FT). The first track first side extension EPS1(FT) and the second side extension EPS2(FT) together extend along the x-axis direction across or define a first track extension length dimension EPDX(FT), and the y-axis separation between the first track first side extension EPS1(FT) and the second side extension EPS2(FT) defines a nominal width dimension GFADY(FT) of the first track generated magnetic field field. Similarly, the second track first side extension EPS1(ST) and the second track second side extension EPS2(ST) extend along the x-axis direction adjacent the first and second sides of the second track generated magnetic field field GFA(ST). The second track first side extension EPS1(ST) and the second track second side extension EPS2(ST) together extend along the x-axis direction across or define a second track extension length dimension EPDX(ST), and the y-axis separation between the second track first side extension EPS1(ST) and the second side extension EPS2(ST) defines a nominal width dimension GFADY(ST) of the second track generated magnetic field field.

[0089] The first track magnetic field generating coil section FGCP(FT) further comprises a first track shielded end section SES(FT) which is fabricated in the first track shielded end layer (shielded conductor layer) of the multilayer circuit element as already outlined, spans the y-axis distance between the first track first side extension section EPS1(FT) and the first track second side extension section EPS2(FT), and is included in the end conductor path ECP(FT) which also includes an interlayer connection as shown, and connects the first track first side extension section EPS1(FT) and the first track second side extension section EPS2(FT) in the first track magnetic field generating coil section FGCP(FT). The second track magnetic field generating coil section FGCP(ST) further comprises a second track shielded end SES(ST) which is fabricated in the second track shielded end layer (shielded conductor layer) of the multilayer circuit element as already outlined, spans the y-axis distance between the second track first side extension section EPS1(ST) and the second track second side extension section EPS2(ST), is included in the end conductor path ECP(ST) which also includes an interlayer connection as shown, and connects the second track first side extension section EPS1(ST) and the second track second side extension section EPS2(ST) in the second track magnetic field generating coil section FGCP(ST).

[0090] In the particular embodiment shown in Figure 6, the first track shielding end configuration SEC(FT) comprises the first track shielded end SES(FT) described above and the first track conductive shielding region CSR(FT), which in one embodiment may be configured substantially as shown in dashed outline in the first track shielding end configuration SEC(FT) in Figure 6. The second track shielding end configuration SEC(ST) comprises the second track shielded end SES(ST) described above and the second track conductive shielding region CSR(ST), which in one embodiment may be configured substantially as shown in dashed outline in the second track shielding end configuration SEC(ST) in Figure 6. As shown in Figure 6, the conductive shielding regions CSR(FT) and CSR(ST) may be considered to be included in a conductive shielding region configuration CSRC (which may in some embodiments include an additional conductive shielding region CSR'). In accordance with the principles outlined above, the conductive shielding regions CSR(FT) and CSR(ST) generally extend to various extents along the x-axis and y-axis directions in various embodiments and are fabricated in one or more shielding region layers located between the shielded end layer (shielded conductor layer) of the detection portion 667 and one or more receiving loop layers of the detection portion 667 with respect to their position along the z-axis direction.

[0091] As shown in Fig. 6, the plurality of sensing elements SEN' each constitutes a conductive receiving loop CRL' fabricated in one or more receiving loop layers of a multi-layer circuit element to operate according to the principles outlined above. However, one difference in the sensing elements SEN' compared to the previously described embodiment is that in the plurality of sensing elements, the conductive receiving loops CRL' of the sensing elements SEN' extend along the y-axis direction so as to overlap both the first pattern track FPT and the second pattern track SPT. Thus, they are distributed along the x-axis direction over both the first track sensing element area SEA(FT) and the second track sensing element area SEA(ST) nominally aligned with the second pattern track SPT. The sensing element SEN' is therefore configured to provide a detection signal or a detection signal contribution in response to a local effect on a first track changing magnetic flux provided by an adjacent signal modulation element SME of the first pattern track FPT of the scale pattern 680 and also in response to a local effect on a second track changing magnetic flux provided by an adjacent signal modulation element SME of the second pattern track SPT of the scale pattern 680.

[0092] As shown by the current flow arrows in FIG. 6, the magnetic field generating coil FGC is configured to generate a first track change magnetic flux having a first polarity in the first track generated magnetic field field GFA(FT) and a second track change magnetic flux having a second polarity opposite to the first polarity in the second track generated magnetic field field GFA(ST). The conductive receiving loop CRL' extends along the y-axis direction in both the first track sensing element area SEA(FT) and the second track sensing element area SEA(ST) and is configured to provide the same sensing loop polarity in the first track sensing element area SEA(FT) and the second track sensing element area SEA(ST). This configuration works in combination with a scale track offset of about WL / 2 in the first pattern track FPT and the second pattern track SPT to enhance the signal contribution from the first track sensing element area SEA(FT) and the second track sensing element area SEA(ST) in each of the sensing elements SEN'.

[0093] In the particular embodiment illustrated in FIG. 6, the conductive receiving loop CRL′ overlaps some of the extensions of the magnetic field generating coil. Thus, in this particular embodiment of the detector 667, the extension layer(s) EPL are not the same layer as the receiving loop layer of the multi-layer circuit element, and blind vias (as the term is used in printed circuit board manufacturing techniques, or other multi-layer manufacturing techniques) may be required for the fabrication of the conductive receiving loop CRL′ so that the conductive receiving loop CRL′ remains insulated from the extension layer(s) EPL. However, based on the teachings of the present disclosure, a person of ordinary skill in the art would understand that such an embodiment is merely exemplary and not limiting.

[0094] It will be understood that a signal processing unit (e.g. analogous to the signal processing unit 566) may be operatively connected to the detection unit 667 via two input connections ICP1 and ICP2 and via detection signal output connections SDS1 and SDS2 in a manner analogous to that already outlined with reference to Fig. 5 and / or known in the art. The signal processing unit may also be configured to provide coil drive signals to the field generating coil FGC at the two input connections ICP1, ICP2. The signal processing unit may further be configured to determine a relative position between the detection unit 667 and the scale pattern' 680 based on detection signals input from the detection unit 667, for example at the detection signal output connections SDS1 and SDS2.

[0095] It will be appreciated that the connections (e.g. connections ICPFTST, ICP1, ICP2, interlayer connections, etc.) and conductive shielding regions CSR' used in the input portion INP are similar to the end conductor portions ECP, shielded ends SES and conductive shielding regions CSR used in the first track shielding end configuration SEC(FT) and the second track shielding end configuration SEC(ST) of Fig. 6. It will be appreciated that in various embodiments it will be advantageous to utilize principles similar to those disclosed with reference to the first track shielding end configuration SEC(FT) and the second track shielding end configuration SEC(ST) to shield the various connections (and, if desired, the circuits and connections associated with the signal processing portion) of the input portion INP.

[0096] It will be appreciated that the detector 667 shown in Figure 6 and described above includes important and noteworthy features already outlined with reference to Figures 4 and 5, which differ from those used in detectors of known prior art electromagnetic inductive encoders and provide the benefits and advantages already outlined.

[0097] Briefly, first, the first track sensing element region SEA(FT) extends along the x-axis direction over a first track sensing element region length dimension SEADX(FT) that is longer than the first track extension length dimension EPDX(FT). Similarly, the second track sensing element region SEA(ST) extends along the x-axis direction over a second track sensing element region length dimension SEADX(ST) that is longer than the second track extension length dimension EPDX(ST).

[0098] Second, the first track shielded end SES(FT) is configured such that its z-direction projection along the z-direction toward the receive loop layer at least partially overlaps the conductive receive loop CRL' in the first track sense element area SEA(FT). Similarly, the second track shielded end SES(ST) is configured such that its z-direction projection along the z-direction toward the receive loop layer at least partially overlaps the conductive receive loop CRL' in the second track sense element area SEA(ST).

[0099] Third, the first track conductive shielding region CSR(FT) is configured in the first track shielding region layer between the first track shielded end SES(FT) and the conductive receiving loop CRL' in the first track sensing element region SEA(FT) and blocks at least half or more of the area of ​​the z-axis projection of the first track shielded end SES(FT) overlapping with the conductive receiving loop CRL' in the first track sensing element region SEA(FT). Similarly, the second track conductive shielding region CSR(ST) is configured in the second track shielding region layer (which may be the same as the first track shielding region layer) between the second track shielded end SES(ST) and the conductive receiving loop CRL' in the second track sensing element region SEA(ST) and blocks at least half or more of the area of ​​the z-axis projection of the second track shielded end SES(ST) overlapping with the conductive receiving loop CRL' in the second track sensing element region SEA(ST).

[0100] The conductive shielding regions CSR(FT) and CSR(ST) shown in FIG. 6 are configured to block all of the areas of the z-axis projection of the first track shielded ends SES(FT) and the second track shielded ends SES(ST) that overlap the conductive receiving loops CRL' of the first track sensing element region SEA(FT) and the second track sensing element region SEA(ST) (except for the insulated holes surrounding the conductive interlayer connections). This may be advantageous in various embodiments. However, in some embodiments, a significant and sufficient benefit to accuracy can be obtained if the first track conductive shielding region CSR(FT) and the second track conductive shielding region CSR(ST) are configured to block at least half or more of the areas of the z-axis projection of the first track shielded ends SES(FT) and the second track shielded ends SES(ST), even if they are somewhat reduced along the x-axis direction. This and other modifications according to the principles already outlined may be made in the detection unit 667.

[0101] FIG. 7 is an isometric "wireframe" view illustrating a third exemplary embodiment of a detector 767 according to principles disclosed herein and a compatible scale pattern 680 usable in an electromagnetic inductive encoder. The scale pattern 680 may be similar or identical to the scale pattern 680 described with reference to FIG. 6. The detector 767 is substantially similar to the detector 667 described with reference to FIG. 6 and may be understood by analogy, except for the differences outlined below. Elements designated with like reference numerals (e.g., similar names or numbers or numeric "suffixes") in FIG. 7 and FIG. 6 may be understood to be similar elements and operate similarly and provide similar benefits and advantages, except as otherwise noted below.

[0102] Generally speaking, the main differences between the embodiment of FIG. 7 and the embodiment of FIG. 6 relate to the specific functionality of the magnetic field generating coil FGC′ and the plurality of sensing elements SEN″ that constitute the conductive receiving loop CRL″, as will be explained in more detail below.

[0103] As shown in Fig. 7, in the magnetic field generating coil FGC', the input part INP has a different configuration from that in Fig. 6. In particular, the connection part ICP2 is connected to the extension part EPS2(ST) rather than the extension part EPS1(ST), and the connection part ICPFTST is connected to the extension part EPS2(FT) and the extension part EPS1(ST) rather than the extension part EPS2(ST).

[0104] As shown in FIG. 7, the plurality of sensing elements SEN″ include crossings or twists of conductive traces in their conductive receiving loops CRL″ in the region including the first track extension and the second track extension between the first track generated magnetic field region and the second track generated magnetic field region, thereby providing opposite sensing loop polarities in each sensing element SEN″ in the first track sensing element region SEA(FT) and the second track sensing element region SEA(ST).

[0105] As a result, as shown by the current flow arrows in FIG. 7, the magnetic field generating coil FGC′ is configured to generate a first track change magnetic flux having a first polarity in the first track generated magnetic field field GFA(FT) and a second track change magnetic flux having the same polarity as the first polarity in the second track generated magnetic field field GFA(ST). The twisted conductive receiving loop CRL″ configured as described above provides opposite sense element polarities in the first track sense element area SEA(FT) and the second track sense element area SEA(ST). This configuration, working in combination with a scale track offset of about WL / 2 in the first pattern track FPT and the second pattern track SPT, enhances the signal contribution from the first track sense element area SEA(FT) and the second track sense element area SEA(ST) in each of the sense elements SEN″. The detection unit 767 thus provides substantially similar signals and advantages as the detection unit 667 described above.

[0106] FIG. 8 is a plan view of a fourth exemplary embodiment of a detector 867 according to principles disclosed herein and an interchangeable scale pattern 180 that can be used in an electromagnetic inductive encoder.

[0107] Scale pattern 180 may be similar or identical to scale pattern 180 described with reference to Figures 4 and 5. Detection portion 867 is substantially similar to detection portion 467 described with reference to Figures 4 and 5 and may be understood by analogy, except for the differences outlined below. Elements designated with like reference numbers (e.g., like names or numbers or numeric "suffixes") in Figure 8 and Figures 4 and 5 may be understood to be similar elements, operate similarly, and provide similar benefits and advantages, except as otherwise noted below.

[0108] Generally speaking, the main differences between the embodiment of FIG. 8 and the embodiments of FIGS. 4 and 5 relate to the specific functionality of the field generating coil FGC″, as will be explained in more detail below.

[0109] The various generated magnetic field regions FGCs previously described herein may be characterized as "single-turn" configurations in which only one conductive turn or loop surrounds the generated magnetic field region GFA. In some embodiments, such a turn or loop may be a partial loop that incompletely surrounds the generated magnetic field region GFA but nevertheless provides an operable generated magnetic field thereat. In contrast, the detection portion 867 shown in FIG. 8 comprises a "two-turn" configuration, as described in more detail below.

[0110] It can be seen in FIG. 8 that the extensions EPXXxx(FT) of the magnetic field generating coil FGC″ are fabricated in the extension layer of the detection part 867 according to the principles already outlined. Other parts of the magnetic field generating coil FGC″, such as the shielded ends SESx(FT) shown in FIG. 8 with dark filling, are fabricated in the shielded end layer (shielded conductor layer) of the detection part 867 according to the principles already outlined. Such connections between layers are made by interlayer connections F-THRU according to the principles already outlined. The interlayer connections F-THRU are represented by black filled circles in FIG. 8.

[0111] As shown in FIG. 8, the magnetic field generating coil FGC″ has the following configuration:

[0112] The input connection portion CP1 is connected at a first end of the magnetic field generating coil FGC″ (i.e., a first end of the first track extension length dimension EPDX(FT)) to a first first side extension portion EPS1a(FT) that is connected in series to a first second side extension portion EPS2a(FT) by a shielded end portion SESa(FT) of a shielding end configuration SEC(FT).

[0113] The first second side extension portion EPS2a(FT) is connected in series to the second first side extension portion EPS1b(FT) by a shielded end portion SESab(FT) of a shielded end configuration SEC(FT) provided at a second end of the magnetic field generating coil FGC″ (i.e., a second end of the first track extension portion dimension EPDX(FT)).

[0114] The second first side extension portion EPS1b(FT) is connected in series to the second second side extension portion EPS2b(FT) by a shielded end portion SESb(FT) of a shielding end configuration SEC(FT) provided at a first end of the magnetic field generating coil FGC″ (i.e., a first end of the first track extension length dimension EPDX(FT)).

[0115] And the second second side extension portion EPS2b(FT) is connected to the input connection portion CP2 adjacent to the shielding end arrangement SEC(FT) of the second end of the magnetic field generating coil FGC″ (i.e., the second end of the first track extension portion dimension EPDX(FT)).

[0116] It should be appreciated that such a two-turn configuration may be advantageous or desirable in a detection portion in accordance with the principles disclosed herein, where the magnetic field generating coil FGC″ may be significantly shorter along the x-axis direction than that used in previously known detection portions providing similar performance and accuracy. As already described herein, the significantly shorter extensions EP permitted in accordance with the principles disclosed and claimed herein essentially allow the magnetic field generating coil FGC″ to have significantly less resistance and / or impedance compared to known magnetic field generating configurations. As a result, additional turns or loops may be added to the magnetic field generating coil FGC″ to tune (increase) the impedance to a desired level to drive resonant oscillation of the coil in some embodiments, without exceeding practical or desirable limits on the resistance and / or impedance of the magnetic field generating coil FGC″. In some such embodiments, unexpectedly high signal-to-noise ratios and / or accuracy may be achieved. It should be appreciated that in some embodiments, it may be preferable to use a magnetic field generating coil FGC that is a “three-turn” configuration or a configuration with more turns.

[0117] FIG. 9 is a block diagram illustrating one exemplary embodiment of components of a measurement system 900 including an electromagnetic induction encoder 910. Of course, some numbered components 9XX of FIG. 9 may correspond to and / or have similar operation as similarly numbered components 1XX of FIG. 1, except as specified below. The electromagnetic induction encoder 910 includes a signal processing unit 966, a scale 970 and a detection unit 967 that together form a transducer. In various embodiments, the detection unit 967 may include any of the configurations described with respect to FIGS. 2-8 or other configurations. The measurement system 900 further includes a user interface, such as a display 938 and user operable switches 934, 936, and may additionally include a power source 965. In various embodiments, an external data interface 932 may be included. All of these elements are coupled to a signal processing unit 966 (or signal processing and control circuitry), which may be embodied as a signal processor. The signal processing unit 966 may provide a drive signal to the magnetic field generating coil of the detection unit 967 and, based on the detection signal input from the detection unit 967, determine the position of the sensing element of the detection unit 967 relative to the scale 970, as outlined earlier in this specification.

[0118] In various embodiments, the signal processor 966 of FIG. 9 (and / or other signal processor configurations shown and described herein) may include or consist of one or more processors that execute software to perform the functions described herein. The 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 a random access memory (RAM), a read-only memory (ROM), a flash memory, or the like, or a combination of such components. The software may also be stored in one or more storage devices, such as optical-based disks, flash memory devices, or any other type of non-volatile storage medium that stores data. The software may include one or more program modules, including routines, programs, objects, components, data structures, and the like, 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 across multiple computer systems or devices and accessed via service calls in a wired or wireless configuration.

[0119] The disclosure described below with reference to Figures 10-15 introduces an element or configuration referred to as a signal connection arrangement (or SCA for short) that may be used in a sense winding portion (e.g., SWPh1 or SWPh2) of an electromagnetic inductive encoder to further reduce or eliminate certain position error components due to the effects of stray magnetic fields associated with the inter-layer connections included in the magnetic field generating coil FGC described above. In general, the SCA may be configured to compensate and / or minimize respective undesired sense signal components arising from respective sense signal inter-layer connection pairs associated with the sense winding connections (e.g., DSFT1 and DSFT2) that receive stray magnetic fluxes arising from the inter-layer connections included in the magnetic field generating coil FGC described above via an inter-layer connection inductive coupling area FTIArea disposed between the sense signal inter-layer connection pairs.

[0120] In contrast, the signal connection arrangements used in the sense windings as disclosed in the '335 patent or as previously described herein do not recognize or explicitly take into account such unwanted sense signal components or their potential sources, and thus do not explicitly describe or recognize properties of the signal connection arrangements that compensate for or minimize the respective unwanted sense signal components, as disclosed in more detail below. Any similarities between the previously disclosed signal connection arrangements and those disclosed and claimed below may be deemed to be coincidental or unintentional.

[0121] In some embodiments, SCAs configured according to the principles disclosed below may be used in combination with one or more teachings disclosed in the '335 patent and / or as previously disclosed herein with reference to Figures 4-8 to further improve signal to noise ratio, accuracy, and / or size in electromagnetic induction encoders. In some embodiments, the use of SCAs as disclosed herein may be combined with the teachings disclosed in commonly assigned, pending U.S. application Ser. No. 16 / 863,543, the entirety of which is incorporated herein by reference, to further improve signal to noise ratio, accuracy, and / or size in electromagnetic induction encoders. The SCA configurations shown and described in detail below are conveniently categorized and referred to as being configured according to a first type of arrangement characteristic designated A) or a second type of arrangement characteristic designated B). Additionally, some SCA configurations may be categorized as being configured according to both arrangement characteristic B) and arrangement characteristic A).

[0122] In the following description of Figures 10-15, for convenience of description due to the design and characteristic differences highlighted in this embodiment compared to those already disclosed, the conductor layer previously referred to as the shielded end layer will be referred to below using the more general designation "shielded conductor layer". For similar reasons, a set of shielding layer conductors is newly defined to encompass all of the various conductor portions made in the shielded conductor layer of the multilayer circuit element. In contrast to the approach of the previous description, this set of shielding layer conductors groups various functional elements, such as shielding layer conductors included in the field generating coils and / or shielding layer conductors connected to the sensing windings, as will be described in more detail below. For the purpose of relating the previous description to the following description, it will be understood that at least one such shielding layer conductor included in the set is similar or identical to an element previously mentioned herein and is identical to an element mentioned in the references incorporated herein as "shielded end SES". This element may alternatively be described as a shielded-layer transverse conductor portion that spans at least the minimum y-axis separation between the first track first side extension and the second side extension and is included in a conductor path (e.g., including an extension interlayer connection) connecting the first track first side extension and the second track second side extension of the first track magnetic field generating coil. More generally, the term transverse conductor portion refers to any conductor portion that extends along a direction transverse to the x-axis direction.

[0123] FIG. 10 is an isometric view of a portion of the detector 467 of FIG. 5, including a first embodiment of signal connection arrangements SCA-Ph1 and SCA-Ph2 that may mitigate certain stray signal errors according to the principles disclosed below. FIG. 10 shows a portion of FIG. 5 with parts removed or hidden from view and the remaining portions enlarged for better illustration of the various SCA features. In particular, FIG. 10 shows only the left portion of FIG. 5 with the signal processing section 566 shown in FIG. 5 hidden / removed to more clearly show the features currently shown in that vicinity in FIG. 10. In general, the detector 467 and other features shown in FIG. 10 may be understood to be similar or identical to those shown in FIG. 5, and their operation may be understood based on the preceding description. Elements designated with similar reference numbers (e.g., similar names or numbers or numeric "suffixes") in FIG. 10 and FIG. 5, or elements that are clearly similar in the figures, may be understood to be similar elements and operate similarly, except as otherwise noted below. Unless contradicted by the following description, it will be understood that the various features and concepts previously outlined with reference to Figure 5 and other previously illustrated figures herein are believed to be present and operative in connection with the detector 467 shown in Figure 10 even though such features or concepts or their reference numerals are not shown in Figure 10 in order to more clearly highlight the features and characteristics described below. Only certain features of Figure 10 are described in detail below with the intent to highlight certain disclosed and claimed features not previously expressly described herein.

[0124] Features added in FIG. 10 or shown in more detail compared to FIG. 5 include a first embodiment of a sensing winding configuration with a set of spatial phase sensing windings, each of which includes a first spatial phase sensing winding SWPh1, a second spatial phase sensing winding SWPh2, and a third spatial phase sensing winding SWPh3, and their associated signal connection arrangements SCA-Ph1, SCA-Ph2, and SCA-Ph3. Furthermore, FIG. 10 explicitly displays the previously described input connections ICP1A, ICP2A as extension inter-layer connections EPFT1A, EPFT2A, respectively. FIG. 10 further explicitly shows that the extension inter-layer connections EPFT1A and EPFT2A may be collectively referred to as a subset of extension inter-layer connections EPFTSub. FIG. 10 also shows a stray magnetic field STRAYBF generated by the flow of drive signal currents, represented by arrows, in the subset of extension inter-layer connections EPFTSub.

[0125] The subset of extension inter-layer connections EPFTSub may be considered as a subset of the full set of extensions EPFTSet, which further includes a subset of extension inter-layer connections EPFTSub' located at the distal or right ends of the disconnected extensions EPS1 and EPS2 in Fig. 10. For example, the full set of extensions EPFTSet is shown in Figs. 14 and 15. The set of extension inter-layer connections EPFTSet and its subsets EPFTSub and EPFTSub' may be described as follows: The set of extension inter-layer connections EPFTSet includes extension inter-layer connections (e.g., EPFT1A and EPFT2A) that each extend between an extension layer and a shielded conductor layer along a z-axis direction that is nominally normal to the front surface of the multilayer circuit element. The set of extension inter-layer connections EPFTSet comprises an illustrated first end subset EPFTSub of extension inter-layer connections arranged at a first end of the extension EP of the magnetic field generating coil FGC and a second end subset EPFTSub' of extension inter-layer connections arranged at a second end of the extension EP of the magnetic field generating coil FGC. Each of the first end subset EPFTSub and the second end subset EPFTSub' of extension inter-layer connections is connected to a respective end of the extension EP of the magnetic field generating coil FGC and to a shield layer conductor section and transmits a drive signal therebetween. For example, as shown in FIG. 10, the extension inter-layer connection EPFT1A is connected to an end of the extension EPS1 and to the shield layer conductor section ICP1B. Similarly, the extension inter-layer connection EPFT2A is connected to an end of the extension EPS2 and to the shield layer conductor section ICP2B.

[0126] The stray magnetic field STRAYBF is generated by the flow of drive signal current represented by arrows in the subset of extension inter-layer connections EPFTSub as shown above. The stray magnetic field STRAYBF may be informally referred to as the "B magnetic flux density". In general, when transmitting a drive signal, the subset of extension inter-layer connections EPFTSub generates a respective "inter-layer connection" stray magnetic field STRAYBF including "inter-layer connection" stray flux components oriented in the xy plane parallel to the x-axis and y-axis. For example, the particular structure of the subset of extension inter-layer connections EPFTSub shown in FIG. 10 generates a particular stray magnetic field STRAYBF shown in FIG. 10, having a structure and / or orientation represented qualitatively by flux components and / or magnetic field lines BFL1, BFL2, BFL2', BFL3, and BFL3' approximately in the XY plane.

[0127] The first, second and third spatial phase sensing windings SWPh1, SWPh2 and SWPh3, respectively, have their elements and structures described above in relation to the sensing element SEN and the conductive receiving loop CRL. As previously outlined herein, Figs. 2-8 show a single representative set of sensing elements SEN (e.g., SEN1-SEN24 in Figs. 2-4) that make up a corresponding conductive receiving loop CRL (e.g., CRL1-CRL24 in Figs. 2-3). As previously indicated, the elements SEN and / or CRL are alternatively referred to herein as sensing loop elements, sensing coil elements or sensing winding elements. These elements are connected in series to various layers of a multi-layer circuit element (e.g., connected by inter-layer connections) according to known methods to form a sensing winding in which adjacent loop elements have opposite winding polarities. This is described with respect to the sensing winding SWPh1, which was shown without labeling in Fig. 5 but is explicitly labelled in Fig. 10. In contrast to the previously shown figures of this specification, parts of additional substantially similar sense windings SWPh2 and SWPh3 ​​are also explicitly labeled and shown in FIG. 10. The presence of such sense windings was understood, but not explicitly depicted in the previously shown figures. As already indicated, in the previous figures, to avoid visual confusion, it was understood that a single set of sense elements (i.e. a single sense winding) was illustrated in the detector, where one or more additional sets of sense elements (or sense windings) are provided that are not illustrated (hidden). In particular, it was understood that such "hidden" detectors are provided in a different spatial phase position (e.g. to provide quadrature signals, or three-phase signals) than the illustrated sets of sense elements, according to known principles, as would be understood by a person skilled in the art. In particular, it will be understood by a person skilled in the art based on the following description that the sense winding configuration shown in FIG. 10 is a three-phase detector.To clarify and confirm their construction based on the above description, it will be understood that the first spatial phase sensing winding SWPh1, the second spatial phase sensing winding SWPh2, and the third spatial phase sensing winding SWPh3 ​​each constitute a plurality of sensing elements SEN of respective conductive receiving loops CRL connected in series and fabricated in one or more receiving loop layers of the multi-layer circuit element, where the conductive receiving loops SEN / CRL are distributed along the x-axis direction, at least a first track portion of the conductive receiving loops CRL is disposed over a first track sensing element area SEA that is nominally aligned with the first pattern track FPT, and where each sensing element SEN / CRL of each spatial phase sensing winding SWPh1, SWPh2, and SWPh3 ​​is configured to provide a sensing signal or a sensing signal contribution at least responsive to a local influence on a first track changing magnetic flux provided by an adjacent signal modulation element SME of the scale pattern 180.

[0128] A first embodiment of each of the signal connection arrangements SCA-Ph1, SCA-Ph2, SCA-Ph3 of the sensing winding section shown in FIG. 10 can be described as follows. The first spatial phase signal connection arrangement SCA-Ph1 comprises a pair of detection signal inter-layer connections DSFT1, DSFT2 each extending along the z-axis direction between the receiving loop layer and the shielded conductor layer. In various embodiments, the detection signal inter-layer connection DSFT1 may be connected to a first signal connection node SDS1 (previously called the detection signal output connection) of the first spatial phase sensing winding SWPh1 of the appropriate receiving loop layer, and may further be connected to a signal processing section (e.g., 566) via a corresponding shield layer conductor section as shown in FIG. 10. The detection signal inter-layer connection DSFT2 may be connected to a second signal connection node SDS2 of the first spatial phase sensing winding SWPh1 of the appropriate receiving loop layer, and may further be connected to a signal processing section (e.g., 566) via a corresponding shield layer conductor section as shown in FIG. 10. Thus, according to the present specification, the pair of detection signal inter-layer connections DSFT1, DSFT2 are configured to input the detection signal from the first spatial phase sensing winding SWPh1 to the signal processing unit (e.g., 566). Similarly, the second spatial phase signal connection arrangement SCA-Ph2 includes a pair of detection signal inter-layer connections DSFT1', DSFT2' each extending along the z-axis direction between the receiving loop layer and the shielded conductor layer. In various embodiments, the detection signal inter-layer connection DSFT1' may be connected to a first signal connection node SDS1' of the second spatial phase sensing winding SWPh2 of the appropriate receiving loop layer, and may further be connected to the signal processing unit (e.g., 566) via a corresponding shielding layer conductor section, as shown in FIG. 10. The detection signal inter-layer connection DSFT2' may be connected to a second signal connection node SDS2' of the second spatial phase sensing winding SWPh2 of the appropriate receiving loop layer, and may further be connected to the signal processing unit (e.g., 566) via a corresponding shielding layer conductor section, as shown in FIG. 10. Thus, according to this specification, the pair of sense signal interlayer connections DSFT1', DSFT2' is configured to input the sense signal from the second spatial phase sensing winding SWPh2 to a signal processing unit (eg, 566).Similarly, the third spatial phase signal connection arrangement SCA-Ph3 includes a pair of detection signal inter-layer connections DSFT1″, DSFT2″ each extending along the z-axis direction between the receiving loop layer and the shielded conductor layer. In various embodiments, the detection signal inter-layer connection DSFT1″ may be connected to a first signal connection node SDS1″ of the third spatial phase sensing winding SWPh3 ​​of the appropriate receiving loop layer, and may further be connected to a signal processing unit (e.g., 566) via a corresponding shielding layer conductor portion as shown in FIG. 10. The detection signal inter-layer connection DSFT2″ may be connected to a second signal connection node SDS2″ of the third spatial phase sensing winding SWPh3 ​​of the appropriate receiving loop layer, and may further be connected to a signal processing unit (e.g., 566) via a corresponding shielding layer conductor portion as shown in FIG. 10. Thus, according to this specification, the pair of detection signal inter-layer connections DSFT1″, DSFT2″ is configured to input the detection signal from the third spatial phase sensing winding SWPh3 ​​to the signal processing unit (e.g., 566).

[0129] In various embodiments, it may be advantageous to reduce stray signal coupling if the detection signal interlayer connections DSFT of the first, second and third spatial phase signal connection arrangements SCA-Ph1, SCAPh2 and SCAPh3 are located outside and beyond the edge of the generated magnetic field region GFA with respect to their position along the x-axis direction. This is particularly convenient and advantageous in configurations of position encoders such as those shown in Figures 10-15, in which the sensing element region SEA extends over a sensing element region length dimension SEADX that is longer than the elongation length dimension EPDX along the x-axis direction, as already described herein. However, it should be understood that in other embodiments, the detection signal interlayer connections DSFT of the first, second and third spatial phase signal connection arrangements SCA-Ph1, SCA-Ph2 and SCA-Ph3 may also be located outside and beyond the edge of the generated magnetic field region GFA that is longer than the sensing element region SEA, using suitable conductor parts (circuit traces) for connecting to the sensing elements in the generated magnetic field region GFA. For example, the types of "alignment conductors" described below with reference to Figures 14 and 15 may be suitable in such embodiments.

[0130] Some useful configurations are shown in Fig. 10. As shown in Fig. 10, the detection signal interlayer connection pair DSFT1 / DSFT2 in the first spatial phase signal connection arrangement SCA-Ph1 defines an interlayer connection inductive coupling area plane FTIAP that nominally passes through the axis of each of its paired interlayer connections, and further defines an interlayer connection inductive coupling area FTIArea located at each location between its paired interlayer connections in that plane. Similarly, the detection signal interlayer connection pair DSFT1' / DSFT2' in the second spatial phase signal connection arrangement SCA-Ph2 defines an interlayer connection inductive coupling area plane FTIAP' that nominally passes through the axis of each of its paired interlayer connections, and further defines an interlayer connection inductive coupling area FTIArea' located at each location between its paired interlayer connections in that plane. Similarly, the detection signal interlayer connection pair DSFT1″ / DSFT2″ in the third spatial phase signal connection arrangement SCA-Ph3 defines an interlayer connection inductive coupling area plane FTIAP″ that nominally passes through the axis of each of its paired interlayer connections, and further defines an interlayer connection inductive coupling area FTIArea″ located at each location between its paired interlayer connections within that plane. For ease of illustration, and in broad terms, FIG. 10 shows that a representative stray flux component BFL2 intersects a central area of ​​the interlayer connection inductive coupling area FTIArea′ and forms an incidence angle θ′ with the interlayer connection inductive coupling area plane FTIAP′ in the XY plane. Similarly, according to the conventions used herein, it will be understood that a magnetic flux component of substantially similar magnitude to the representative stray magnetic flux component BFL2 intersects the central region of the interlayer connection inductive coupling regions FTIArea and FTIArea″ and forms incidence angles θ and θ″ with the interlayer connection inductive coupling region planes FTIAP and FTIAP″, respectively, in the XY plane (not shown to avoid visual clutter). As a result, unwanted detection signal components are generated in the associated detection signal interlayer connection pair. For example, for the interlayer connection pair DSFT1 / DSFT2, according to known principles, the unwanted detection signal component USC is as follows in Equation 1: USC=k*BFL*FTIArea*cos(θ) (Equation 1) For the inter-layer connection pair DSFT1′ / DSFT2′, the unwanted detection signal component USC′ is given by Equation 2. USC'=k*BFL*FTIArea'*cos(θ') (Equation 2) For the inter-layer connection pair DSFT1″ / DSFT2″, the unwanted detected signal component USC″ is given by Equation 3. USC”=k*BFL*FTIArea”*cos(θ”) (Equation 3) where k is a proportionality factor and BFL is the magnitude of the applicable (local) stray flux component in the XY plane (e.g., the magnitude of BFL2).

[0131] As previously indicated, the SCA configurations shown and described in Figures 10-15 are conveniently categorized and referenced as being configured according to a first type of arrangement characteristic labeled "A") or a second type of arrangement characteristic labeled "B). In the embodiment shown in Figure 10, the detection signal inter-layer connection pairs DSFT1 / DSFT2, DSFT1' / DSFT2' and DSFT1" / DSFT2" of the first, second and third spatial phase signal connection arrangements SCA-Ph1, SCA-Ph2 and SCA-Ph3 are configured to compensate for respective detection signal components USC, USC' and USC" resulting from receiving respective first, second and third amounts of inter-layer connection stray flux (e.g., BFL2) via respective inter-layer connection inductive coupling regions FTIArea, FTIArea' and FTIArea", respectively, using arrangement characteristic A).

[0132] General arrangement characteristic A) is described as follows for each sense signal interlayer connection pair of each spatial phase signal connection arrangement included in each set of spatial phase sensing windings. In arrangement characteristic A), the detection signal interlayer connection pairs (e.g., DSFT1 / DSFT2, DSFT1' / DSFT2', and DSFT1" / DSFT2") of each spatial phase signal connection arrangement (e.g., SCA-Ph1, SCA-Ph2, and SCA-Ph3) are configured such that their interlayer connection inductive coupling area planes have an angle of up to 25 degrees relative to each other in the XY plane, and the detection signal interlayer connection pairs (e.g., DSFT1 / DSFT2, DSFT1' / DSFT2', and DSFT1" / DSFT2") of each spatial phase signal connection arrangement (e.g., SCA-Ph1, SCA-Ph2, and SCA-Ph3) are arranged close to each other in the XY plane such that their interlayer connection inductive coupling areas (e.g., FTIArea, FTIArea', and FTIArea") receive interlayer connection stray magnetic flux components (e.g., BFL2) that similarly intersect in the XY plane.

[0133] In the embodiment shown in FIG. 10, the detection signal interlayer connection pairs DSFT1 / DSFT2, DSFT1' / DSFT2' and DSFT1" / DSFT2" of each of the spatial phase signal connection arrangements SCA-Ph1, SCA-Ph2 and SCA-Ph3 are configured to meet the arrangement characteristic A), as described above. In the particular embodiment shown in FIG. 10, the detection signal interlayer connection pairs DSFT1 / DSFT2, DSFT1' / DSFT2' and DSFT1" / DSFT2" of each of the spatial phase signal connection arrangements SCA-Ph1, SCA-Ph2 and SCA-Ph3 are further configured such that their interlayer connection inductive coupling areas FTIArea, FTIArea' and FTIArea" are nominally small and equal, and their interlayer connection inductive coupling area planes FTIAP, FTIAP' and FTIAP" are nominally parallel. This is believed to be the most advantageous or ideal embodiment to meet the arrangement characteristic A). In this embodiment, the differences between USC, USC', and USC" are minimized according to Equations 1, 2, and 3. However, it should be understood that this particular embodiment is illustrative only and not limiting, as explained below.

[0134] With respect to the angles between the interlayer connection inductive coupling region planes FTIAP, FTIAP', and FTIAP", it will be appreciated that if the interlayer connection inductive coupling regions FTIArea, FTIArea', and FTIArea" similarly receive interlayer connection stray flux components that intersect, then the difference between the angles θ, θ', θ" in Equations 1-3 will be the same as the angle between the interlayer connection inductive coupling region planes FTIAP, FTIAP', FTIAP". For any given size and / or size coincidence of regions FTIArea, FTIArea', and FTIArea", it is advantageous to make the difference between the angles θ, θ', θ" as small as possible (e.g., 15 degrees, or 10 degrees or less) in order to make the difference between the unwanted detected signal components USC, USC', USC" as small as possible. Thus, in various embodiments, it is advantageous to make the angle between the interlayer connection inductive coupling region planes FTIAP, FTIAP', and FTIAP" as small as possible. Conversely, for a given tolerance between the unwanted detection signal components USC, USC', and USC", once the angles between the interlayer connection inductive coupling region planes FTIAP, FTIAP', and FTIAP" (and the angles between angles θ, θ', θ") are reduced below the 25 degree limit mentioned in arrangement characteristic A) (e.g., as small as 15 degrees or 10 degrees or less), it may be possible and / or desirable (e.g., for flexibility in the layout design of the detection section, or for other reasons) to relax the constraints or tolerances on the size and / or coincidence of the regions FTIArea, FTIArea', and FTIArea". However, it should be appreciated that when regions FTIArea, FTIArea', and FTIArea" are relatively small and well matched (e.g., when each is minimized and matched to the limit permitted by typical manufacturing techniques and tolerances used in the detection portion), the unwanted detection signal components USC, USC', and USC" and / or the differences therebetween may be essentially small, and controlling the angle between the interlayer connection inductive coupling region planes FTIAP, FTIAP', and FTIAP" to be at most 25 degrees (as described in arrangement characteristic A) may provide sufficient or desired accuracy in many applications.That is, by controlling the angle between the interlayer connection inductive coupling region planes FTIAP, FTIAP', and FTIAP" to be at most 25 degrees, the differences between the unwanted detection signal components USC, USC', and USC" are suppressed to be much smaller than their individual values ​​(e.g., half or much smaller than their individual values ​​depending on the nominal incidence angle θ (or θ' or θ")). This is a worthwhile achievement for error reduction. The smaller differences between the unwanted detection signal components USC, USC', and USC" are more reliably compensated for or eliminated to a more desirable level when using applicable "common mode error" compensation techniques employed in known three-phase (e.g., 0, 120, 240 degree spatial phase) processing methods, for example, as disclosed in U.S. Pat. No. 6,859,762, which is incorporated herein in its entirety.

[0135] Regarding the significance of the differences between the interlayer connection inductive coupling regions FTIArea, FTIArea', and FTIArea", as indicated above, if the angles between the interlayer connection inductive coupling region planes FTIAP, FTIAP', and FTIAP" (and the angles between the angles θ, θ', θ") are reduced below the 25 degree limit mentioned in arrangement characteristic A) (e.g., made as small as practical), for a given tolerance between the unwanted detection signal components USC, USC', and USC", it may be possible and / or desirable (e.g., for flexibility in the layout design of the detection section, or for other reasons) to relax the constraints or tolerances on the size and / or coincidence of the interlayer connection inductive coupling regions FTIArea, FTIArea', and FTIArea". This is particularly true, for example, when the interlayer connection inductive coupling region planes FTIAP, FTIAP', and FTIAP" are nominally parallel to their intersecting interlayer connection stray flux components. In such a case, the unwanted detection signal components USC, USC', and USC" would ideally be zero, regardless of the size or matching of the interlayer connection inductive coupling regions FTIArea, FTIArea', and FTIArea". However, while this may not be necessary in some particular embodiments, due to potential manufacturing variations, or potential unpredictable stray magnetic field variations, etc., in many embodiments it may be desirable to match the interlayer connection inductive coupling regions to at most 20%, or even 10% or less in difference.

[0136] Whether the detection signal interlayer connection pairs (e.g., DSFT1 / DSFT2, DSFT1' / DSFT2' and DSFT1" / DSFT2") of each spatial phase signal connection arrangement (e.g., SCA-Ph1, SCA-Ph2 and SCA-Ph3) are located sufficiently close to each other in the XY plane such that their interlayer connection inductive coupling regions (e.g., FTIArea, FTIArea' and FTIArea") receive similar intersecting interlayer connection stray magnetic flux components (e.g., BFL2) in the XY plane depends on both the structure of the stray magnetic field STRAYBF and the actual proximity of the interlayer connection inductive coupling regions FTIArea, FTIArea' and FTIArea". The sufficiency and / or appropriateness of these factors in a particular embodiment may be determined by analysis and / or experimentation.

[0137] While the usefulness of using arrangement characteristic A) in conjunction with a three-phase detector has been outlined above with reference to FIG. 10, it will be appreciated that arrangement characteristic A) is also generally useful in conjunction with detectors including four respective space phase windings, or more, to compensate for similar common mode errors (e.g., additional errors analogous to USC, USC', and USC" in the additional space phase windings). Differential signal processing methods for compensating for or "removing" common mode errors in four-phase quadrature detectors (e.g., 0, 90, 180, 270 degree spatial phases) are known in the art.

[0138] In contrast, however, common mode errors are not easily removed by signal processing in sensing windings that include only two spatial phases, such as in a two-phase quadrature sensing configuration (e.g., 0, 90 degree spatial phase). In such two-phase sensing winding configurations, it is desirable to minimize or eliminate the individual winding signal error components (e.g., USC and / or USC') using geometry characteristics B) specified herein, as described below.

[0139] FIG. 11 is an isometric view illustrating a detector 467A that is substantially similar to the detector 467A shown in FIG. 10, except that it includes a second embodiment of signal connection arrangements SCA-Ph1 and SCA-Ph2 that include only two spatial phases (e.g., 0.90 degree spatial phases) and can mitigate certain stray signal errors according to the principles disclosed below. Elements designated with similar reference numbers (e.g., similar names or numbers or numerical "suffixes") in FIG. 11 and 10 and FIG. 5, or elements that are clearly similar in the figures, can be understood to be similar elements and to operate similarly, except as otherwise noted below. It will be understood that, unless contradicted by the following description, various features and concepts already outlined with reference to FIG. 5 and other previously shown figures herein are considered to be present and operative in connection with the detector 467A shown in FIG. 11, even though such features or concepts or their reference numbers are not shown in FIG. 11 to more clearly highlight certain features and characteristics described below. Due to the aforementioned similarities, only certain clarifications and / or differences between FIG. 11 and FIG. 10 are described in detail below.

[0140] The main difference between the detection section 467A shown in FIG. 11 and the detection section 467 shown in FIG. 10 is that the signal connection arrangements SCA-Ph1 and SCA-Ph2 (i.e., their respective detection signal interlayer connection pairs) are rotated by a similar amount about the z-axis direction such that their associated interlayer connection inductive coupling area planes FTIAP and FTIAP', respectively, are angled at a relatively small angle with respect to the intersecting interlayer connection stray flux component BFL2 in the XY plane.

[0141] As indicated above, the SCA configurations shown and described in Figures 10-15 are conveniently categorized and referenced as being configured according to a first type of arrangement characteristic denoted as "A") and / or a second type of arrangement characteristic denoted as "B). In the embodiment shown in Figure 11, the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second spatial phase signal connection arrangements SCA-Ph1 and SCA-Ph2, respectively, are configured to compensate and / or minimize or eliminate respective detection signal components USC and USC' resulting from receiving first and second amounts of respective interlayer connection stray flux (e.g., BFL2) via respective interlayer connection inductive coupling regions FTIArea and FTIArea' using arrangement characteristic B) outlined below.

[0142] General layout characteristic B) is described for the sense signal inter-layer connection pair of each spatial phase signal connection arrangement included in each set of spatial phase sensing windings as follows: In layout characteristic B), the sense signal inter-layer connection pairs (e.g., DSFT1 / DSFT2 and DSFT1' / DSFT2') of each spatial phase signal connection arrangement (e.g., SCA-Ph1 and SCA-Ph2) are each configured such that their inter-layer connection inductive coupling region planes (e.g., FTIAP and FTIAP') have an angle of up to 25 degrees in the XY plane with respect to the inter-layer connection stray flux components (e.g., BFL2) that are parallel to the XY plane and pass through the central regions of their inter-layer connection inductive coupling regions.

[0143] In the embodiment shown in Figure 11, the detection signal inter-layer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first spatial phase signal connection arrangement SCA-Ph1 and the second spatial phase signal connection arrangement SCA-Ph2 are respectively configured to conform to the arrangement characteristic B). In particular, the respective inter-layer connection inductive coupling region planes (FTIAP, FTIAP') are rotated relative to their angles in Figure 10 to be at an angle of up to 25 degrees in the XY plane with respect to the inter-layer connection stray flux components (e.g., BFL2) that are parallel to the XY plane and pass through the central regions of those inter-layer connection inductive coupling region(s).

[0144] In the particular embodiment shown in FIG. 11, the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second spatial phase signal connection arrangements SCA-Ph1 and SCA-Ph2, respectively, are further configured such that their interlayer connection inductive coupling areas FTIArea and FTIArea' are nominally small and equal, and each of their interlayer connection inductive coupling area planes FTIAP and FTIAP' are nominally parallel and angled at a small angle (e.g., 10 degrees or less) in the XY plane with respect to the associated interlayer connection stray flux components (e.g., BFL2) passing through the central regions of their interlayer connection inductive coupling areas FTIArea and FTIArea'. This is believed to be a near-ideal embodiment that meets arrangement characteristic B). However, as explained below, it should be understood that this particular embodiment is illustrative only and not limiting.

[0145] Regarding the angle between each of the interlayer connection inductive coupling area planes FTIAP or FTIAP' and the interlayer connection stray magnetic flux component (e.g., BFL2) that is parallel to the XY plane and passes through the central area of ​​the interlayer connection inductive coupling area of ​​the associated detection signal interlayer connection pair, certain factors can be evaluated as follows. The expression "passes through the central area of ​​the interlayer connection inductive coupling area of ​​the associated detection signal interlayer connection pair" is a useful explanation in practice. In the above explanations of Figures 10 and 11, it is assumed that the curvature and gradient of the magnetic field is not significant at the location of the interlayer connection inductive coupling areas FTIArea and FTIArea', and the operational interlayer connection stray magnetic flux component in the XY plane can be approximated by BFL2 for each. However, in cases where the curvature and gradient of the magnetic field are significant such that this assumption does not apply, the expression "passes through the central area of ​​the interlayer connection inductive coupling area of ​​the associated detection signal interlayer connection pair" is a useful explanation in such a situation. With respect to the angle between each interlayer connection inductive coupling area plane FTIAP or FTIAP' and the interlayer connection stray flux components parallel to the XY plane (e.g., BFL2), by analogy with the previous discussion, if the interlayer connection inductive coupling area planes FTIAP and FTIAP' are nominally parallel to their interlayer connection stray flux components that intersect, the unwanted detection signal components USC and USC' will ideally be zero, regardless of the size or coincidence of the interlayer connection inductive coupling areas FTIArea and FTIArea'. Thus, in some embodiments, it is advantageous for the angle between each interlayer connection inductive coupling area plane FTIAP or FTIAP' and the interlayer connection stray flux components parallel to the XY plane to be as small as possible (e.g., as shown in FIG. 11) in order to make the unwanted detection signal components USC and USC' as small as possible.However, by analogy with the same previous discussion, if the areas FTIArea and FTIArea' are relatively small and well matched (e.g., each is minimized and matched to the limit allowed by typical manufacturing techniques and tolerances used for the detection section), the unwanted detection signal components USC and USC' may be inherently small, and controlling the angle between the interlayer connection inductive coupling area plane FTIAP or FTIAP' and the interlayer connection stray flux component parallel to the XY plane (e.g., BFL2) in the central area of ​​the interlayer connection inductive coupling area FTIArea or FTIArea' of the associated detection signal interlayer connection pair to be at most 25 degrees (as stated in arrangement characteristic B) can provide sufficient or desired accuracy in many applications. That is, by controlling the angle between the interlayer connection inductive coupling area plane FTIAP, FTIAP' and the interlayer connection stray flux component parallel to the XY plane (e.g., BFL2) to a maximum of 25 degrees in the central area of ​​the interlayer connection inductive coupling area FTIArea or FTIArea' of the associated sense signal interlayer connection pair, the unwanted sense signal components USC, USC' are suppressed to be individually much smaller than if a larger angle were allowed (e.g., due to lack of understanding of its importance). This may be a valuable measure for error reduction in some embodiments. Smaller unwanted sense signal components USC and USC' provide a more accurate position measurement (e.g., according to known two-phase quadrature signal processing methods).

[0146] By analogy with the previous explanation of the importance of the difference between the interlayer connection inductive coupling areas FTIArea and FTIArea', for a given tolerance limit for the unwanted detection signal components USC, USC', it may be possible and / or desirable (e.g. for layout design flexibility in the detection section or for other reasons) to relax the constraints or tolerances on the size and / or matching of the interlayer connection inductive coupling areas FTIArea and FTIArea' when the angle between each of the interlayer connection inductive coupling area planes FTIAP and FTIAP' and the interlayer connection stray flux components parallel to the XY plane in the central area of ​​the interlayer connection inductive coupling area FTIArea or FTIArea' of the associated detection signal interlayer connection pair is reduced to below the 25 degree limit mentioned in the arrangement characteristic B) (e.g. below 10 degrees). This is especially the case if, for example, the angle is made nearly zero. As mentioned above, in such a case, the unwanted detection signal components USC and USC' will ideally be zero, regardless of the size or matching of the interlayer connection inductive coupling areas FTIArea and FTIArea'. However, while this may not be necessary in some particular embodiments, due to potential manufacturing variations, potential unpredictable stray magnetic field variations, etc., in many embodiments it may be desirable to match the interlayer connection inductive coupling regions to a difference of at most 20%, or even 10% or less.

[0147] Whether each interlayer connection inductive coupling area plane (FTIAP, FTIAP') of the detection signal interlayer connection pair (e.g., DSFT1 / DSFT2 and DSFT1' / DSFT2') of the first and second spatial phase signal connection arrangements (e.g., SCA-Ph1 and SCA-Ph2) is configured to be at most 25 degrees in the XY plane with respect to the interlayer connection stray magnetic flux component (e.g., BFL2) parallel to the XY plane in the central area of ​​the interlayer connection inductive coupling area FTIArea and FTIArea' of the associated detector signal interlayer connection pair depends on knowing and adapting the structure of the stray magnetic field STRAYBF. The relevant structure of the stray magnetic field STRAYBF in a particular embodiment may be determined by analysis and / or experiment.

[0148] While the utility of using arrangement characteristic B) in connection with a two-phase detector section has been outlined above with reference to FIG. 11, it will be appreciated that arrangement characteristic B) is also generally useful in combination with detector sections including three or four or more respective space phase windings to minimize or eliminate errors outlined above (e.g., additional errors analogous to USC and USC' in additional space phase windings). It should be noted that in the embodiment shown in FIG. 11, in addition to conforming to arrangement characteristic B), the sense signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second space phase signal connection arrangements SCA-Ph1, SCA-Ph2, respectively, also conform to arrangement characteristic A), as will be understood based on their similarity to their counterparts in FIG. 10. Also, although not required, configurations conforming to arrangement characteristic A) in addition to arrangement characteristic B) may be advantageous and / or desirable in various two-phase, three-phase, and / or four-phase sense winding sections.

[0149] FIG. 12 is an isometric view illustrating a detector 467B that is substantially similar to the detector 467A shown in FIG. 11, except that it includes a third embodiment of signal connection arrangements SCA-Ph1 and SCA-Ph2 that can mitigate certain stray signal errors according to the principles disclosed below. Elements designated with similar reference numbers (e.g., similar names or numbers or numeric "suffixes") in FIG. 12, 11 and 10 and FIG. 5, or elements that are clearly similar in the figures, may be understood to be similar elements and to operate similarly, except as otherwise noted below. Unless contradicted by the following description, it will be understood that various features and concepts already outlined with reference to FIG. 5 and other previously shown figures herein are considered to be present and operative in connection with the detector 467B shown in FIG. 12, even though such features or concepts or their reference numbers are not shown in FIG. 12 to more clearly highlight certain features and characteristics described below. Due to the aforementioned similarities, only certain clarifications and / or differences between FIG. 12 and FIG. 11 will be described in detail below.

[0150] The main difference of the detection section 467B shown in Fig. 12 compared to the detection section 467A shown in Fig. 11 is that the signal connection arrangement SCA-Ph1 (i.e. its respective detection signal inter-layer connection pair) is moved to a different position on the sense winding SWPh1 and rotated at that position about the z-axis direction by an amount such that its associated inter-layer connection inductive coupling area plane FTIAP is angled with respect to its local / operative inter-layer connection stray flux component BFL2' in the XY plane to comply with the arrangement characteristic B). That is, the detection signal inter-layer connection pair DSFT1 / DSFT2 of the first spatial phase signal connection arrangement SCA-Ph1 is configured such that its inter-layer connection inductive coupling area plane FTIAP has an angle of up to 25 degrees in the XY plane with respect to the inter-layer connection stray flux component BFL2' that is parallel to the XY plane and passes through a central area of ​​its inter-layer connection inductive coupling area. Because the detection signal inter-layer connection pair DSFT1' / DSFT2' of the second spatial phase signal connection arrangement SCA-Ph2 is in the same position and has the same rotation compared to the configuration of FIG. 11, it will be understood that in the embodiment shown in FIG. 12, the detection signal inter-layer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second spatial phase signal connection arrangements SCA-Ph1 and SCA-Ph2, respectively, are configured to compensate and / or minimize or eliminate respective detection signal components USC and USC' resulting from receiving first and second amounts of respective inter-layer connection stray magnetic flux (e.g., BFL2' and BFL2, respectively) via the respective inter-layer connection inductive coupling areas FTIArea and FTIArea', respectively, using arrangement characteristic B) outlined below.

[0151] In contrast to the embodiment shown in FIG. 11, the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first spatial phase signal connection arrangement SCA-Ph1 and the second spatial phase signal connection arrangement SCA-Ph2 are not close to each other in the XY plane, and their interlayer connection inductive coupling area planes FTIAP and FTIAP' are angled relative to each other by more than 25 degrees in the XY plane, and therefore do not comply with arrangement characteristic A).

[0152] In the particular embodiment shown in FIG. 12, the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second spatial phase signal connection arrangements SCA-Ph1 and SCA-Ph2, respectively, are further configured such that their interlayer connection inductive coupling areas FTIArea and FTIArea' are nominally small and equal, and each of their interlayer connection inductive coupling area planes FTIAP and FTIAP' are angled at a nominally small angle (e.g., 10 degrees or less) in the XY plane with respect to the interlayer connection stray flux components (BFL2' or BFL2, respectively) that are parallel to the XY plane and pass through the central areas of their interlayer connection inductive coupling areas FTIArea and FTIArea'. This is believed to be a near-ideal embodiment that meets arrangement characteristic B) for the reasons already described with reference to FIG. 11. However, it should be understood that this particular embodiment is merely illustrative and not limiting, as already described with reference to FIG. 11.

[0153] The angle in the XY plane between each interlayer connection inductive coupling area plane FTIAP or FTIAP' and the interlayer connection stray magnetic flux components (e.g. BFL2' and BFL2, respectively) that are parallel to the XY plane and pass through the central area of ​​the interlayer connection inductive coupling area FTIArea or FTIArea' of their associated detection signal interlayer connection pair has been previously described with reference to Figure 11 and does not need to be described in detail here. In brief, by analogy with the previous description, in some embodiments, it is advantageous to make the angle between each interlayer connection inductive coupling area plane FTIAP or FTIAP' and the interlayer connection stray magnetic flux components (BFL2' and BFL2) in the XY plane as small as possible (e.g. to 10 degrees or less as shown in Figure 12) in order to make the unwanted detection signal components USC and USC' as small as possible. However, by analogy with the previous discussion, when the regions FTIArea and FTIArea' are relatively small and well-matched, controlling the angle in the XY plane between each of the interlayer connection inductive coupling region planes FTIAP and FTIAP' and the interlayer connection stray magnetic flux components (BFL2' and BFL2, respectively) that are parallel to the XY plane and pass through the central region of the interlayer connection inductive coupling region FTIArea or FTIArea' of their associated detection signal interlayer connection pair to be at most 25 degrees can provide sufficient or desired accuracy in many applications.

[0154] It should be noted that the significance of the difference between the interlayer connection inductive coupling areas FTIArea and FTIArea' has already been explained with reference to Fig. 11 and therefore need not be explained in detail here. In brief, by analogy with the previous explanation of the given tolerance limits for the unwanted detection signal components USC, USC', it may be possible and / or desirable (e.g. for layout design flexibility in the detection section or for other reasons) to relax the constraints or tolerances on the size and / or matching of the interlayer connection inductive coupling areas FTIArea and FTIArea' when the angle in the XY plane between each of the interlayer connection inductive coupling area planes FTIAP and FTIAP' and the interlayer connection stray flux components parallel to the XY plane and passing through the central area of ​​the interlayer connection inductive coupling area FTIArea or FTIArea' of their associated detection signal interlayer connection pair is reduced to below the 25 degree limit mentioned in the arrangement characteristic B) (e.g. below 10 degrees). This is especially the case when the angle is made approximately zero, for example. However, while this may not be necessary in some particular embodiments, due to potential manufacturing variations, potential unpredictable stray magnetic field variations, etc., in many embodiments it may be desirable to match the interlayer connection inductive coupling regions to a difference of at most 20%, or no more than 10%.

[0155] FIG. 13 is an isometric view illustrating a detector 467C that is substantially similar in many respects to the detector 467A shown in FIG. 11, except that it includes a fourth embodiment of signal connection arrangements SCA-Ph1 and SCA-Ph2 that may mitigate certain stray signal errors using additional design concepts or principles compared to FIG. 11, as described in more detail below. Elements designated with similar reference numbers (e.g., similar names or numbers or numeric "suffixes") in FIG. 13, 12, 11, and 10 and FIG. 5, or elements that are clearly similar in the figures, may be understood to be similar elements and to operate similarly, except as otherwise noted below. It will be understood that, unless contradicted by the following description, various features and concepts already outlined with reference to FIG. 5 and other previously shown figures herein are believed to be present and operative in connection with the detector 467C shown in FIG. 13, even though such features or concepts or their reference numbers are not shown in FIG. 13 to more clearly highlight certain features and characteristics described below. Due to the aforementioned similarities, only certain clarifications and / or differences between FIG. 13 and FIG. 11 are described in detail below.

[0156] 11, the main difference between the detection section 467C shown in FIG. 13 and the detection section 467A shown in FIG. 11 is that the signal connection arrangements SCA-Ph1 and SCA-Ph2 (i.e., their respective detection signal interlayer connection pairs) are moved to different positions and rotated in position to conform to the arrangement characteristic B). Furthermore, specific "alignment" conductor portions are added to the signal connection arrangements SCA-Ph1 and SCA-Ph2 to connect the rearranged interlayer connection pairs to their respective associated spatial phase detection windings SWPh1 and SWPh2, all of which will be described in more detail below.

[0157] Before describing specific embodiments of the interlayer connection pairs of signal connection arrangements SCA-Ph1, SCA-Ph2 according to arrangement characteristic B), it is useful to explain certain concepts related to the structure of the stray magnetic field STRAYBF. As shown before, arrangement characteristic B) requires that each interlayer connection inductive coupling area plane (FTIAP, FTIAP') is aligned at an angle of at most 25 degrees in the XY plane with respect to the interlayer connection stray magnetic flux components that are parallel to the XY plane and pass through the central area of ​​those interlayer connection inductive coupling areas. This depends on whether or not you know the structure of the stray magnetic field STRAYBF.

[0158] However, it should be understood that it is only necessary to know the structure of the stray magnetic field STRAYBF at the actual location of the interlayer connection inductive coupling area FTIArea, FTIArea' in the interlayer connection inductive coupling area plane FTIAP, FTIAP'. The embodiment of the interlayer connection pair of signal connection arrangements SCA-Ph1 and SCA-Ph2 shown in Figures 13-14 is based on the concept that, given the known structure of the set of extension interlayer connections EPFTSet including the subsets EPFTSub and EPFTSub', at a specific location, the structure of the stray magnetic field STRAYBF can be reliably predicted or inferred, as explained before. Thus, the interlayer connection pair of signal connection arrangements SCA-Ph1 and SCA-Ph2 can be implemented to meet the arrangement characteristic B) at their specific location without analytically or experimentally determining the detailed overall structure and directionality of the stray magnetic field STRAYBF.

[0159] In the particular embodiment shown in Fig. 13, a first end subset of extension inter-layer connections EPFTSub is arranged at the first ends of the extensions EPS1 and EPS2 of the magnetic field generating coil FGC and consists of two extension inter-layer connections EPFT1A and EPFT2A connected to the respective first track extensions EPS1 and EPS2. A second end subset of extension inter-layer connections EPFTSub' is arranged at the second ends of the extensions EPS1 and EPS2 of the magnetic field generating coil FGC and consists of two extension inter-layer connections (not shown or removed in Fig. 13, but shown as elements ECP1A and ECP2A in Fig. 5) connected to the respective first track extensions EPS1 and EPS2. As shown in Fig. 13, this embodiment in combination with the set of extension inter-layer connections EPFTSet (as shown in Fig. 13 and Fig. 5) and the flow of drive signal currents therein can be reliably expected to produce a relatively symmetrical magnetic stray field STRAYBF. In particular, the stray magnetic field STRAYBF is parallel to the x-axis and z-axis directions and symmetric along an XZ mid-plane XZMid (represented by a segment of that plane in FIG. 13) that is aligned with respect to the y-axis direction along the center of the first track-generated magnetic field area GFA (indicated by the dashed line MIDrefY in FIG. 13 (approximately halfway between the two extension interlayer connections EPFT1A and EPFT2A)). As shown in FIG. 13, along that XZ mid-plane, the symmetric stray magnetic field STRAYBF can be reliably predicted to have a straight interlayer connection magnetic flux component BFL1 in the XY plane. Thus, in the embodiment shown in FIG. 13, the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second spatial phase signal connection arrangements SCA-Ph1 and SCA-Ph2, respectively, are positioned close to the XZ mid-plane with their interlayer connection inductive coupling areas FTIArea and FTIArea' parallel to the x-axis and z-axis directions and aligned along the center of the first track generated magnetic field area GFA in the y-axis direction, and each of their interlayer connection inductive coupling area planes FTIAP and FTIAP' are aligned in the XY plane at an angle of up to 10 degrees with respect to the XZ mid-plane, or more advantageously, at an angle that allows for manufacturing tolerances.As will be appreciated based on the above description, in various embodiments, this ensures that for the interlayer connecting flux components BFL1 located in the XZ mid-plane, they comply with the geometry characteristic B).

[0160] In the particular embodiment shown in FIG. 13, the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first spatial phase signal connection arrangement SCA-Ph1 and the second spatial phase signal connection arrangement SCA-Ph2 are further configured such that their interlayer connection inductive coupling areas FTIArea and FTIArea' are nominally small and equal, and their interlayer connection inductive coupling area planes FTIAP and FTIAP' are nominally parallel. They are also nominally aligned with the XZ mid-plane and thus with the interlayer connection magnetic flux component BFL1. This is considered to be an almost ideal embodiment that meets the arrangement characteristic B) for the reasons already explained with reference to FIG. 11. However, it should be understood that this particular embodiment is merely exemplary and not limiting, as already explained with reference to FIG. 11 and further explained below.

[0161] In the embodiment shown in Fig. 13, the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first spatial phase signal connection arrangement SCA-Ph1 and the second spatial phase signal connection arrangement SCA-Ph2 are located along the x-axis direction beyond the ends of the sensing elements SEN / CRL of the sensing windings SWPh1 and SWPh2. This requires extending the sensing windings SWPh1 and SWPh2 to those positions, as shown in Fig. 13. In particular, it is advantageous to extend the connection nodes of the sensing windings SWPh1 and SWPh2 by using a pair of alignment conductor parts fabricated in the respective receiving loop layers, as described below. As shown in FIG. 13, in addition to the interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2', the first and second spatial phase signal connection arrangements SCA-Ph and SCA-P2 each have a pair of alignment conductor sections DSACP1 / DSACP2 and DSACP1' / DSACP2', each of which is formed in a respective receiving loop layer.

[0162] In the embodiment shown in Fig. 13, in the pair of alignment conductor sections DSACP1 / DSACP2, the alignment conductor section DSACP1 extends from a first portion of the conductive receiver loop CRL of its associated spatial phase sensing winding SWPh1 to provide a first signal connection node SDS1 at a location where it connects to the detection signal inter-layer connection DSFT1 associated with that spatial phase sensing winding SWPh1. The alignment conductor section DSACP2 extends from a second portion of the same conductive receiver loop CRL of its associated spatial phase sensing winding SWPh1 to provide a second signal connection node SDS2 at a location where it connects to the detection signal inter-layer connection DSFT2 associated with that spatial phase sensing winding SWPh1. Similarly, in the pair of alignment conductor sections DSACP1' / DSACP2', the alignment conductor section DSACP1' extends from a first portion of the conductive receiver loop CRL of its associated spatial phase sensing winding SWPh2 to provide a first signal connection node SDS1' at a location where it connects to the detection signal inter-layer connection DSFT1' associated with that spatial phase sensing winding SWPh2. The alignment conductor section DSACP2' extends from a second portion of the same conductive receiver loop CRL of its associated spatial phase sensing winding SWPh2 to provide a second signal connection node SDS2' at a location that connects to the detection signal interlayer connection DSFT2' associated with that spatial phase sensing winding SWPh2. Each pair of alignment conductor sections DSACP1 / DSACP2 and / or DSACP1' / DSACP2' are configured in their respective receiver loop layers such that at least half or more of their areas are aligned with each other along the z-axis direction, thereby reducing or preventing significant stray coupling signals that may otherwise occur in the conductor sections DSACP1 / DSACP2. Ideally, the alignment conductor sections DSACP1 / DSACP2 are aligned to the maximum extent possible over their entire length. However, this may not be possible in all implementations due to various circuit layout constraints, etc. It should be understood that alignment conductor sections similar to those described above can be used as needed to support desired layout alternatives in combination with any of the detection sections disclosed herein.

[0163] With respect to each of the interlayer connection inductive coupling area planes FTIAP and FTIAP' being angled in the XY plane with respect to the XZ mid-plane by at most 10 degrees, or more advantageously to allow for manufacturing tolerances, the 10 degree (or better) limit is easily achieved using practical manufacturing tolerances, since the location of the XZ mid-plane is clear based on the physical characteristics of the detection section 467C. Furthermore, the 10 degree (or better) limit allows for some margin of error for the interlayer connection flux component BFL1 nominally present in the XZ mid-plane to ensure that the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second spatial phase signal connection arrangements SCA-Ph1, SCA-Ph2 comply with the arrangement characteristic B) (i.e., allows for margin of error with respect to the 25 degree limit represented by the arrangement characteristic B). This is sufficient for many applications, as already explained with reference to Figures 11 and 12, and does not need to be explained in detail here.

[0164] As shown in FIG. 13, the interlayer connection inductive coupling area planes FTIAP and FTIAP' are nominally parallel to each other and also nominally aligned with the XZ mid-plane, and therefore aligned with the interlayer connection magnetic flux component BFL1. In short, by analogy with the previous explanation, in some embodiments, in order to make the unwanted detection signal components USC and USC' as small as possible, it is advantageous in terms of precision to make the angle between each of the interlayer connection inductive coupling area planes FTIAP or FTIAP' and the interlayer connection stray magnetic flux component BFL1 in the XY plane as small as possible (e.g., 10 degrees or less), and similarly, their angles relative to each other as small as possible. However, while the degree of angular control included in this embodiment may be desirable, in some applications a looser angular control within the various limits outlined above may be used and still provide sufficient precision. In short, as already explained with reference to FIG. 11 and FIG. 12, this is especially true when the areas FTIArea and FTIArea' are relatively small and well-matched (e.g., as shown in FIG. 13).

[0165] It should be noted that the significance of the difference between the interlayer connection inductive coupling areas FTIArea and FTIArea' has already been explained with reference to Figures 11 and 12 and therefore need not be explained in detail here. In brief, by analogy with the previous explanation, it is possible and / or desirable (e.g. for layout design flexibility in the detection section or for other reasons) to relax the constraints or tolerances on the size and / or coincidence of the interlayer connection inductive coupling areas FTIAP and FTIAP' when the angle between each of the interlayer connection inductive coupling area planes FTIAP and FTIAP' and the interlayer connection stray flux component BFL1 (nominally located in the XZ mid-plane) is reduced below the limits outlined above (e.g. 25 degrees, or 10 degrees, or less) for a given tolerance limit of the unwanted detection signal components USC and USC'. This is especially the case if the angle is reduced to approximately zero, for example. However, while this may not be necessary in some particular embodiments, due to potential manufacturing variations, potential unpredictable stray magnetic field variations, etc., in many embodiments it may be desirable to match the interlayer connection inductive coupling regions to a difference of at most 20%, or no more than 10%.

[0166] FIG. 14 is an isometric view illustrating a detector 767A that is substantially similar in many respects to the detector 767 shown in FIG. 7, except that it includes a fifth embodiment of signal connection arrangements SCA-Ph1 and SCA-Ph2 substantially similar to those shown in FIG. 13 that may mitigate or eliminate certain stray signal errors according to principles disclosed below. FIG. 14 shows portions of FIG. 7 removed or hidden from view and the remaining portions enlarged to better illustrate various SCA features. Elements designated with similar reference numbers (e.g., similar names or numbers or numeric "suffixes") in FIG. 14 and FIG. 13 and FIG. 7, or elements that are clearly similar in the figures, may be understood to be similar elements and to operate similarly, except as otherwise noted below. Unless contradicted by the following description, it will be understood that the various features and concepts previously outlined with reference to Figure 7 and other previously illustrated figures herein are believed to be present and operative in connection with the detector 767A shown in Figure 14, even though such features or concepts or their reference numerals are not shown in Figure 14 in order to more clearly highlight the particular features and characteristics described below. Because of the aforementioned similarities, only certain clarifications and / or differences between Figures 14 and 13 are described in detail below.

[0167] It will be understood that the implementation of the interlayer connection pairs of the signal connection arrangements SCA-Ph1 and SCA-Ph2 are similar or identical to their counterparts shown in FIG. 13. Due to this similarity, it will be understood that the interlayer connection pairs of the signal connection arrangements SCA-Ph1 and SCA-Ph2 shown in FIG. 14 are similarly configured to comply with the arrangement characteristic B). In general, the interlayer connection pairs of the signal connection arrangements SCA-Ph1 and SCA-Ph2 shown in FIG. 14, as well as their various functions, features, variations, and advantages and disadvantages, may be understood based on the description of their counterparts with reference to FIG. 13 and need not be repeated here. However, it should be understood that the XZ mid-plane shown and described in FIG. 14 is distinct from the XZ mid-plane described with reference to FIG. 13, as described in more detail below.

[0168] Briefly, the main difference of the detector 767a shown in FIG. 14 compared to the detector 467C shown in FIG. 13 relates to the fact that, as shown, the detector 767A is a "two-track" detector including a first and a second track (identified as FTrack and STrack). The first and second tracks cooperate to reduce certain errors in the resulting detection signal. The characteristics and operation of the first and second tracks have been described in detail with reference to FIG. 7 and need not be described here. The relevant function of the "two-track" detector 767A for the purposes of this specification is to generate a somewhat different structure in its symmetrical stray field STRAYBF compared to that generated by the "single-track" detector 467C shown in FIG. 13, as will be explained below.

[0169] In the particular embodiment shown in Fig. 14, a first end subset of extension inter-layer connections EPFTSub is arranged at a first end of the set of extensions EP of the magnetic field generating coil FGC and is composed of four extension inter-layer connections connected to respective first track extensions EPS1(FT) and EPS2(FT) and second track extensions EPS1(ST) and EPS2(ST). A second end subset of extension inter-layer connections EPFTSub' is arranged at a second end of the set of extensions EP of the magnetic field generating coil FGC and is composed of four extension inter-layer connections connected to respective first track extensions EPS1(FT) and EPS2(FT) and second track extensions EPS1(ST) and EPS2(ST). In each of the first end subset EPFTSub and the second end subset EPFTSub', the two adjacent extension inter-layer connections in the center (central extension inter-layer connections) are connected to the adjacent first track extension EPS2 (FT) and second track extension EPS1 (ST), respectively, as shown in Fig. 14 and as shown and described in detail with reference to Fig. 7. In the embodiment shown in Fig. 14, the field generating coils FGC are configured such that the current of the drive signal flows in opposite directions in the two adjacent central extension inter-layer connections and the polarity of the magnetic field is the same in the first track generated magnetic field region and in the second track generated magnetic field region, as already described with reference to Fig. 7 and as shown by the arrows indicating the current flow of the drive signal in Fig. 14.

[0170] This embodiment, in combination with the set of extension interlayer connections EPFTSet (as shown in FIG. 14 and FIG. 7) and the current flow of the drive signal therein, can be reliably expected to produce a relatively symmetrical magnetic stray field STRAYBF, with a symmetrical structure qualitatively illustrated in FIG. 14. In particular, the magnetic stray field STRAYBF shown in FIG. 14 is symmetrical along an XZ mid-plane XZMid (indicated by the dashed line MIDrefY in FIG. 14) that is parallel to the x-axis direction and the z-axis direction and nominally aligned midway between two adjacent central extension interlayer connections or nominally aligned midway between the first track and the second track generated magnetic field field GFA with respect to the y-axis direction. As shown in FIG. 14, along this XZ mid-plane, the symmetrical magnetic stray field STRAYBF can be reliably expected to have a straight interlayer connection magnetic flux component BFL1 in the XY plane. 14, the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second spatial phase signal connection arrangements SCA-Ph1 and SCA-Ph2 are configured to be located close to an XZ mid-plane where their interlayer connection inductive coupling areas FTIArea and FTIArea' are nominally aligned midway between two adjacent central extension interlayer connections or nominally aligned midway between the first and second track generated magnetic field areas GFA in the y-axis direction, and each of their interlayer connection inductive coupling area planes FTIAP and FTIAP' are angled in the XY plane by up to 10 degrees to this XZ mid-plane, or more advantageously, to allow for manufacturing tolerances. As will be understood based on the above description, in various embodiments, this ensures that they comply with the arrangement characteristic B) with respect to the interlayer connection magnetic flux component BFL1 located in the XZ mid-plane.

[0171] As indicated previously, the various functions, features, variants, and advantages and disadvantages of the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second spatial phase signal connection arrangements SCA-Ph1 and SCA-Ph2, as well as the alignment conductor pairs DSACP1 / DSACP2 and DSACP1' / DSACP2' shown in Fig. 14, can be understood based on the discussion of their counterparts with reference to Fig. 13 and need not be described in detail here. In brief, it can be noted that in the embodiment shown in Fig. 14, the interlayer connection inductive coupling area planes FTIAP and FTIAP' are nominally parallel to each other and nominally aligned with the XZ mid-plane (e.g., within 10 degrees, preferably as aligned as possible), and the areas FTIArea and FTIArea' are relatively small and well matched (e.g., the difference is 20% or less, preferably as well matched as possible) for the reasons already explained with reference to Fig. 13.

[0172] FIG. 15 is an isometric view illustrating a detector 667A, which in many respects is substantially similar to the detector 667 shown in FIG. 6, except that it includes a sixth embodiment of signal connection arrangements SCA-Ph1 and SCA-Ph2 according to a combination of design principles and concepts outlined above with reference to FIG. 14, which may mitigate or eliminate certain stray signal errors according to principles disclosed below. FIG. 15 shows portions of FIG. 6 removed or hidden from view and the remaining portions enlarged to better illustrate the various SCA features. Elements designated with similar reference numbers (e.g., similar names or numbers or numeric "suffixes") in FIG. 15 and FIG. 14 and / or FIG. 6, or elements that are clearly similar in the figures, may be understood to be similar elements and to operate similarly, except as otherwise noted below. Unless contradicted by the following description, it will be understood that the various features and concepts already outlined with reference to Figure 6 and other previously illustrated figures herein are believed to be present and operative in connection with the detector 667A shown in Figure 15 even though such features or concepts or their reference numerals are not shown in Figure 15 in order to more clearly highlight the particular features and characteristics described below. Because of the similarities discussed above, only certain clarifications and / or differences of the features of Figure 15 as compared to the corresponding features of Figure 14 are described in detail below.

[0173] In brief, like the detector 767A shown in Fig. 14, the detector 667A shown in Fig. 15 is a two-track detector, but with a different configuration of field generating coils FGC and a different stray magnetic field STRAYBF. Due to the characteristics of the different stray magnetic field STRAYBF described in detail below, the interlayer connection pairs of the signal connection arrangements SCA-Ph1 and SCA-Ph2 shown in Fig. 15 are advantageously configured to comply with arrangement characteristic B), as previously described with reference to Fig. 14 and described in detail below.

[0174] Generally, the interlayer connection pairs DSFT1 / DSFT2 and DSFT1′ / DSFT2′ of the signal connection arrangements SCA-Ph1 and SCA-Ph2 shown in FIG. 15, as well as their various functions, features, variations, and advantages and disadvantages, can be understood based on the description of their counterparts with reference to FIG. 14 and need not be described in detail here. However, they may be seen to be rotated 90 degrees with respect to their counterparts in FIG. 14. Concepts related to their specific locations and their different orientation angles in the two-track detector 667A shown in FIG. 15 are described below.

[0175] The detector 667A shown in FIG. 15 is a "two-track" detector including a first track and a second track (identified as FTrack and STrack) as shown. The first track and the second track cooperate to reduce certain errors in the resulting detector signal. The characteristics and operation of the first track and the second track have been described in detail with reference to FIG. 6 and need not be described here. A relevant feature of the "two-track" detector 667A to be discussed here is the structure of its symmetrical stray field STRAYBF, as described below.

[0176] In the particular embodiment shown in Fig. 15, a first end subset of extension inter-layer connections EPFTSub is arranged at a first end of the set of extensions EP of the magnetic field generating coil FGC and is composed of four extension inter-layer connections connected to respective first track extensions EPS1(FT) and EPS2(FT) and second track extensions EPS1(ST) and EPS2(ST). A second end subset of extension inter-layer connections EPFTSub' is arranged at a second end of the set of extensions EP of the magnetic field generating coil FGC and is composed of four extension inter-layer connections connected to respective first track extensions EPS1(FT) and EPS2(FT) and second track extensions EPS1(ST) and EPS2(ST). The two adjacent central extension inter-layer connections in each of the first end subset EPFTSub and the second end subset EPFTSub' are connected to the adjacent first track extension EPS2(FT) and second track extension EPS1(ST), respectively, as shown in Fig. 15 and as shown and described in detail with reference to Fig. 6. In the embodiment shown in Fig. 15, in contrast to the embodiment shown in Fig. 14, the field generating coil FGC is configured such that the current of the drive signal flows in the same direction in the two adjacent central extension inter-layer connections and the polarities of the magnetic field are opposite to each other in the first track generated magnetic field region and in the second track generated magnetic field region, as already explained with reference to Fig. 6 and as shown by the arrows showing the current flow of the drive signal in Fig. 15.

[0177] This embodiment, in combination with the set of extension interlayer connections EPFTSet (as shown in Fig. 15 and Fig. 6) and the flow of drive signal currents therein, can be reliably expected to produce a stray magnetic field STRAYBF having a structure qualitatively illustrated in Fig. 15. In particular, the stray magnetic field STRAYBF shown in Fig. 15 can be reliably expected to constitute interlayer connection magnetic flux components (e.g. BFL1 in Fig. 15) that include curvature but are locally approximately perpendicular to the XZ mid-plane XZMid shown in Fig. 15 (or in an alternative explanation, are locally aligned to the YZ plane) where they intersect with that XZ mid-plane. The XZ mid-plane XZMid shown in Fig. 15 will be understood to be represented by a segment of that plane, parallel to the x-axis direction and the z-axis direction, and aligned nominally midway between two adjacent central extension interlayer connections or aligned nominally midway between the first track and the second track generated magnetic field areas GFA with respect to the y-axis direction (indicated by the dashed line MIDrefY in Fig. 15).

[0178] Thus, in the embodiment shown in FIG. 15, the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second spatial phase signal connection arrangements SCA-Ph1 and SCA-Ph2 are configured such that their interlayer connection inductive coupling areas FTIArea and FTIArea' are nominally aligned midway between two adjacent central extension interlayer connections in the y-axis direction or are located close to this XZ mid-plane which is nominally aligned midway between the first track and second track generated magnetic field areas GFA, and their interlayer connection inductive coupling area planes are at an angle of up to 10 degrees in the XY plane with respect to the YZ plane perpendicular to the XZ mid-plane, or more advantageously, allowing for manufacturing tolerances. Following the same principles outlined above with reference to their counterparts in FIG. 11, in various embodiments, it will be appreciated that this ensures that at the locations of the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2', and in particular at the location of their midline, they comply with the arrangement characteristic B) with respect to the interlayer connection flux component BFL1 that is nominally parallel to the YZ plane perpendicular to the XZ midplane.

[0179] As indicated previously, the various functions, features, variants, and advantages and disadvantages of the detection signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second spatial phase signal connection arrangements SCA-Ph1 and SCA-Ph2, as well as the alignment conductor pairs DSACP1 / DSACP2 and DSACP1' / DSACP2' shown in Fig. 15, can be understood based on the discussion of their counterparts with reference to Fig. 14 and need not be described in detail here. In brief, it should be noted that in the embodiment shown in Fig. 15, the interlayer connection inductive coupling area planes FTIAP and FTIAP' are nominally parallel to the YZ plane and arranged to intersect with the XZ mid-plane (e.g., at their mid-lines), and the areas FTIArea and FTIArea' are relatively small and well-matched (preferably as well-matched as possible, e.g., with a difference of 20% or less) for the reasons already explained with reference to Fig. 14. This is believed to be a nearly ideal embodiment meeting configuration characteristic B) for reasons previously explained herein, however, it should be understood that this particular embodiment is merely exemplary and not limiting as previously explained herein.

[0180] While the utility of using arrangement characteristic B) in conjunction with two-phase sensing sections has been outlined above with reference to FIGS. 12-15, it will be appreciated that arrangement characteristic B) is also generally useful in conjunction with sensing sections including three or four or more respective space phase windings to minimize or eliminate the errors outlined above (e.g., USC in the additional space phase windings, and additional errors analogous to USC'). It is noted that in the embodiment shown in FIGS. 13-15, in addition to conforming to arrangement characteristic B), the sense signal interlayer connection pairs DSFT1 / DSFT2 and DSFT1' / DSFT2' of the first and second space phase signal connection arrangements SCA-Ph1, SCA-Ph2, respectively, may be configured to conform to arrangement characteristic A) if desired. Also, although not required, a configuration to conform to arrangement characteristic A) in addition to arrangement characteristic B) may be advantageous and / or desirable in various two-phase, three-phase, and / or four-phase sensing winding sections.

[0181] While preferred embodiments of the present disclosure have been shown and described, numerous variations in the arrangement and sequence of operation of the features shown and described will be apparent to those skilled in the art based on this disclosure. Various alternatives can be used to implement the principles disclosed herein. The various embodiments and features described above may be combined to provide further embodiments. All of the U.S. patents and U.S. patent applications referred to herein are incorporated herein by reference in their entirety. Aspects of the embodiments can be modified to use concepts from the various patents and applications, if necessary, to provide still further embodiments. By way of example, it will be understood that the various features and principles disclosed herein may be applied to a rotary encoder. Here, the x-axis and y-axis directions referred to in the above description and claims will be interpreted as corresponding to the circular measurement axis and radial directions, respectively, when applied to such a rotary position encoder.

[0182] These and other changes can be made to the practice in light of the above detailed description. Generally, in the following claims, the terms used should not be construed to limit the scope of the claims to the specific embodiments disclosed in the specification and the claims, but rather to include all possible embodiments along with the full scope of equivalents to which such claims are entitled.

Claims

1. 1. An electromagnetic inductive encoder usable to measure a relative position between two elements along a measurement axis direction coincident with an x-axis direction, comprising: a scale extending along a measurement axis direction and having a signal modulation scale pattern, the signal modulation scale pattern including at least a first pattern track having a pattern track width dimension along a y axis direction orthogonal to the x axis direction, each pattern track including signal modulation elements arranged to provide a spatially varying characteristic that varies as a periodic function of position along the x axis direction; a detection portion including a multi-layer circuit element mounted proximate to at least the first pattern track and configured to move relative to at least the first pattern track along a measurement axis, the multi-layer circuit element having a front surface facing the scale; a signal processor operatively connected to the detector to provide a coil drive signal and configured to identify a relative position of the detector and the signal modulation scale pattern based on a detection signal input from the detector; The detection unit is a magnetic field generating coil disposed on the multilayer circuit element; A set of shield layer conductor portions; a conductive shielding region configuration; A detection winding configuration, The magnetic field generating coils include: an input section including at least two connections connecting said field generating coils to said signal processing section for providing said coil drive signals; a first track magnetic field generating coil section configured to surround at least a first track generating magnetic field region aligned with the first pattern track and generate a first track changing magnetic flux in the first track generating magnetic field region in response to the coil drive signal, the first track magnetic field generating coil section comprising a first track first side extension and a first track second side extension formed in one or more extension layers of the multilayer circuit element and extending along an x-axis direction on a first side and a second side of the first track generating magnetic field region, the first track first side extension and the first track second side extension both extending along the x-axis direction across a first track extension length dimension and having a minimum separation from each other in a y-axis direction that is a minimum width dimension of the first track generating magnetic field region; a set of extension portion inter-layer connections extending between extension portions layers and shielded conductor layers along a z-axis direction normal to a front surface of the multilayer circuit element, the set including a first end subset of extension portion inter-layer connections disposed at first ends of the first track first side extension and the first track second side extension of the magnetic field generating coil, and a second end subset of extension portion inter-layer connections disposed at second ends of the first track first side extension and the first track second side extension of the magnetic field generating coil, each of the first end subset and the second end subset of extension portion inter-layer connections being connected to a respective end of the first track first side extension and the first track second side extension of the magnetic field generating coil and connected to a shield layer conductor portion, the set of extension portion inter-layer connections transmitting a coil drive signal therebetween. the set of shielding layer conductors is fabricated in the shielded conductor layer of the multilayer circuit element, at least one of the shielding layer conductors is a shielded layer crossing conductor extending along a direction transverse to the x-axis direction, at least one of the shielding layer crossing conductors spans at least a minimum separation in the y-axis direction between the first track first side extension and the first track second side extension, and is included in a conductor path including an extension inter-layer connection connecting the first track first side extension and the first track second side extension in the first track magnetic field generating coil section; The conductive shielding region configuration includes at least one first track conductive shielding region fabricated in the shielded conductor layer and a first track shielding region layer extending along a y-axis direction and located between a first track shielded conductor layer and one or more receiver loop layers of the multilayer circuit element with respect to a position along a z-axis direction, including at least one first track conductive shielding region interposed along the z-axis direction between the receiver loop layer and the shielded layer crossing conductor portion spanning at least a minimum separation in the y-axis direction, the first track conductive shielding region being configured to block at least half or more of an area of ​​a z-axis projection of the shielded layer crossing conductor portion toward the receiver loop layer along the z-axis direction; the sense winding section configuration comprises a set of spatial phase sense windings comprising at least two spatial phase sense windings; Each of the spatial phase sensing windings comprises: a plurality of sensing elements having respective conductive receiver loops fabricated in one or more of the receiver loop layers of the multilayer circuit element connected in series, the conductive receiver loops distributed along an x-axis direction, at least first track portions of the conductive receiver loops being disposed across a first track sense element area aligned with a first pattern track, each of the spatial phase sense winding sense elements configured to provide a sense signal or sense signal contribution at least responsive to a local influence on a first track changing magnetic flux provided by an adjacent signal modulating element of a scale pattern; a spatial phase signal connection arrangement including a pair of detection signal inter-layer connections extending along a z-axis direction between the receiving loop layer and the shielded conductor layer, one of the pair of detection signal inter-layer connections being connected to a first signal connection node of a corresponding spatial phase detection winding and connected to the signal processing unit via the corresponding shielding layer conductor portion, and the other of the pair of detection signal inter-layer connections being connected to a second signal connection node of the corresponding spatial phase detection winding and connected to the signal processing unit via the corresponding shielding layer conductor portion, whereby the pair of detection signal inter-layer connections are configured to input detection signals from the respective spatial phase detection windings to the signal processing unit; a detection signal interlayer connection of each spatial phase signal connection arrangement is located outside and beyond an edge of the first track generated magnetic field region with respect to a position along an x-axis direction; when transmitting a coil drive signal, each subset of extension inter-layer connections generates a respective inter-layer connection magnetic stray field that includes inter-layer connection stray flux components oriented in an xy plane parallel to the x-axis and y-axis; each detection signal inter-layer connection pair in each spatial phase signal connection arrangement defines a respective inter-layer connection inductive coupling region plane passing through a central axis of each inter-layer connection of the pair and further defines an inter-layer connection inductive coupling region located within the plane between the inter-layer connections of the pair; a detection signal inter-layer connection pair of each spatial phase signal connection arrangement is configured to compensate or minimize their respective detection signal components resulting from receiving inter-layer connection stray magnetic flux via their respective inter-layer connection inductive coupling regions using at least one of arrangement characteristics A) or B); In the arrangement characteristic A), the detection signal interlayer connection pairs of each spatial phase signal connection arrangement are respectively configured such that their interlayer connection inductive coupling area planes have an angle of up to 25 degrees with each other in the XY plane view, and the detection signal interlayer connection pairs of each spatial phase signal connection arrangement are arranged close to each other in the XY plane view such that their interlayer connection inductive coupling areas receive interlayer connection stray magnetic flux components that cross in the same way in the XY plane view; In the arrangement characteristic B), the detection signal interlayer connection pairs of each spatial phase signal connection arrangement are configured such that their interlayer connection inductive coupling region planes have an angle of up to 25 degrees in the XY plane with respect to the interlayer connection stray magnetic flux components that are parallel to the XY plane and pass through the central regions of their interlayer connection inductive coupling regions.

2. 2. The electromagnetic inductive encoder of claim 1, wherein the set of spatial phase sensing windings comprises at least three of the spatial phase sensing windings, the associated sensing signal interlayer connection pairs of which are configured according to arrangement characteristic A).

3. 3. The electromagnetic induction encoder of claim 2, wherein the associated detection signal interlayer connection pairs are configured such that the areas of their interlayer connection inductive coupling regions differ by up to 20%.

4. 4. The electromagnetic inductive encoder of claim 3, wherein the associated detection signal interlayer connection pairs are configured such that their interlayer connection inductive coupling region planes are parallel.

5. 2. The electromagnetic inductive encoder of claim 1, wherein the set of spatial phase sensing windings comprises at least two of the spatial phase sensing windings, each of whose associated detection signal interlayer connection pairs is configured according to arrangement characteristic B).

6. 6. The electromagnetic induction encoder of claim 5, wherein the associated detection signal inter-layer connection pairs are configured such that their inter-layer connection inductive coupling region planes are parallel to the XY plane and have an angle of up to 10 degrees in the XY plane with respect to inter-layer connection stray magnetic flux components passing through central regions of their inter-layer connection inductive coupling regions.

7. 7. The electromagnetic induction encoder of claim 6, wherein the associated detection signal interlayer connection pairs are configured such that the areas of their interlayer connection inductive coupling regions differ by up to 20%.

8. a first end subset of extension inter-layer connections disposed at the first end of the magnetic field generating coil and a second end subset of extension inter-layer connections disposed at the second end of the magnetic field generating coil each comprise two extension inter-layer connections connected to the first track first side extension and the first track second side extension, Each of the associated detection signal interlayer connection pairs comprises: the interlayer connecting inductive coupling regions are disposed adjacent an XZ mid-plane that is parallel to the x-axis direction and the z-axis direction and aligned along a center of the first track-generated magnetic field region with respect to the y-axis direction; 6. The electromagnetic induction encoder according to claim 5, characterized in that the planes of the interlayer connection inductive coupling regions are configured to have an angle of up to 10 degrees in the XY plane with respect to the XZ intermediate plane.

9. 9. The electromagnetic induction encoder of claim 8, wherein the associated detection signal interlayer connection pairs are configured such that their interlayer connection inductive coupling region planes are parallel to each other.

10. 10. The electromagnetic induction encoder of claim 9, wherein the associated detection signal inter-layer connection pairs are configured such that the areas of their inter-layer connection inductive coupling regions differ by up to 20%.

11. 6. The electromagnetic induction encoder of claim 5, wherein the set of spatial phase sensing windings comprises two spatial phase sensing windings.

12. 6. The electromagnetic induction encoder of claim 5, wherein each of the associated detection signal interlayer connection pairs is further configured according to arrangement characteristic A).

13. the set of spatial phase sensing windings comprises at least two of the spatial phase sensing windings, each of whose associated sensing signal interlayer connection pairs is configured according to arrangement characteristic B); the electromagnetic induction encoder is of a dual track type having the first pattern track and the second pattern track, the magnetic field generating coil having the first track magnetic field generating coil section aligned with the first pattern track and a similar second track magnetic field generating coil section aligned with the second pattern track; a first end subset of extension inter-layer connections disposed at the first end of the magnetic field generating coil and a second end subset of extension inter-layer connections disposed at the second end of the magnetic field generating coil each comprising four extension inter-layer connections connected to the first track first side extension and the first track second side extension and the second track first side extension and the second track second side extension, respectively, two adjacent central extension inter-layer connections in each of the first end subset and the second end subset being connected to adjacent first track second side extension and second track first side extension, respectively; the magnetic field generating coils are configured such that currents of coil drive signals flow in opposite directions in two adjacent central extension inter-layer connections, and a polarity of the magnetic field is the same in the first track generating magnetic field region and the second track generating magnetic field region; The associated detection signal interlayer connection pairs are each the interlayer connection inductive coupling regions are arranged parallel to the x-axis direction and the z-axis direction and adjacent to an XZ mid-plane configured to be located midway between two adjacent central extension interlayer connections or midway between the first track generating magnetic field region and the second track generating magnetic field region with respect to the y-axis direction; 2. The electromagnetic induction encoder according to claim 1, characterized in that the planes of the interlayer connection inductive coupling regions are configured to have an angle of up to 10 degrees with respect to the XZ intermediate plane in the XY plane view.

14. 14. The electromagnetic inductive encoder of claim 13, wherein the associated detection signal interlayer connection pairs are configured such that their interlayer connection inductive coupling region planes are parallel to each other.

15. 15. The electromagnetic inductive encoder of claim 14, wherein each of the associated detection signal inter-strata connections is further configured such that the areas of their inter-strata connection inductive coupling regions differ by up to 20%.

16. the set of spatial phase sensing windings comprises at least two of the spatial phase sensing windings, each of whose associated sensing signal interlayer connection pairs is configured according to arrangement characteristic B); the electromagnetic induction encoder is of a dual track type having the first pattern track and a second pattern track, the magnetic field generating coil having the first track magnetic field generating coil section aligned with the first pattern track and a similar second track magnetic field generating coil section aligned with the second pattern track; a first end subset of extension inter-layer connections disposed at the first end of the magnetic field generating coil and a second end subset of extension inter-layer connections disposed at the second end of the magnetic field generating coil each include four extension inter-layer connections connected to a first track first side extension and a first track second side extension and a second track first side extension and a second track second side extension, respectively, two adjacent central extension inter-layer connections in each of the first end subset and the second end subset are connected to adjacent first track second side extension and second track first side extension, respectively; the magnetic field generating coils are configured such that currents of coil drive signals flow in the same direction in two adjacent central extension inter-layer connections and polarities of magnetic fields are opposite in the first track generating magnetic field region and the second track generating magnetic field region; The associated detection signal interlayer connections are: the interlayer connection inductive coupling regions are arranged parallel to the x-axis direction and the z-axis direction and adjacent to an XZ mid-plane configured to be located midway between two adjacent central extension interlayer connections or midway between the first track generating magnetic field region and the second track generating magnetic field region with respect to the y-axis direction; 2. The electromagnetic induction encoder according to claim 1, characterized in that the planes of the interlayer connection inductive coupling regions are configured to have an angle of up to 10 degrees in the XY plane with respect to the YZ plane perpendicular to the XZ intermediate plane.

17. 17. The electromagnetic inductive encoder of claim 16, wherein the associated detection signal inter-layer connection pairs are each configured such that their inter-layer connection inductive coupling region planes are parallel to the YZ plane and their inter-layer connection inductive coupling regions are intersected by the XZ mid-plane.

18. 20. The electromagnetic inductive encoder of claim 17, wherein each of the associated detection signal inter-strata connections is further configured such that the areas of their inter-strata connection inductive coupling regions differ by up to 20%.

19. Each spatial phase signal connection arrangement further comprises a pair of alignment conductors fabricated in each of the receiving loop layers; a first one of a pair of alignment conductor portions extending from a first portion of a conductive receiver loop of its associated spatial phase sensing winding to provide a first signal connection node at a location that connects to a first one of a pair of detection signal inter-layer connections associated with its spatial phase sensing winding; a second one of the pair of alignment conductor portions extending from a second portion of the conductive receive loop of its associated spatial phase sensing winding to provide a second signal connection node at a location connecting to a second one of the pair of detection signal inter-layer connections associated with its spatial phase sensing winding; 2. The electromagnetic induction encoder according to claim 1, wherein a pair of alignment conductor portions are configured in each of the receiving loop layers such that at least half of their areas are aligned with each other along the z-axis direction.

20. 2. The electromagnetic induction encoder of claim 1, wherein the first track sensing element region extends across a first track sensing element region length dimension along an x-axis direction, the first track sensing element region length dimension along an x-axis direction being greater than the first track extension length dimension along an x-axis direction.

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