Mitutoyo Corporation

Ted Staton Cook

Scott Allen Harsila

Joseph Daniel Tobiason

Michael Nahum

Kazuhiko Hidaka

Christopher Richard Hamner

Norman Laman

Bjorn E B Jansson

James Allen Hitchman

An inductive type absolute electronic position encoder utilizing a single track configuration is provided. The encoder includes a scale portion and a detector portion configured to move relative to each other along a measuring axis direction. The scale portion includes a first scale element portion and a second scale element portion. The detector portion includes a field generating portion configured to generate changing magnetic flux, and a sensing portion including a first sensing element portion configured to operate with the first scale element portion and a second sensing element portion configured to operate with the second scale element portion. The detector portion and the scale portion are arranged in a single track configuration in which the first and second scale element portions are stacked relative to one another and the first and second sensing element portions are at least one of stacked or interleaved relative to one another.

Absolute position encoder utilizing single track configuration

A metrology system is provided for use with a movement system that moves an end tool (e.g., a probe). The metrology system includes a sensor configuration, a light beam source configuration and a processing portion. The sensor configuration comprises a plurality of light beam sensors. The light beam source configuration directs light beams to the light beam sensors of the sensor configuration. One of the light beam source configuration or the sensor configuration is coupled to the end tool and/or an end tool mounting configuration of the movement system which moves the end tool. The light beams that are directed to the light beam sensors cause the light beam sensors to produce corresponding measurement signals. A processing portion processes the measurement signals from the light beam sensors which indicate the position and orientation of the end tool.

Metrology system with position and orientation tracking utilizing light beams

An inductive type position encoder includes a scale, a detector portion and a signal processor. According to one aspect, field generating elements and sensing elements of the detector portion are provided on opposite sides of the scale such that at least part of the scale is between the field generating elements and the sensing elements (transmissive configuration). According to another aspect, the scale comprises a periodic scale pattern including signal modulating elements that are disposed along a scale direction, which is not parallel to a measuring axis direction of the encoder and is slanted at a scale angle relative to the measuring axis direction, such that there is a corresponding y-direction displacement for a given x-direction displacement of the encoder. These aspects of the disclosure make it possible to design a very compact inductive type position encoder, including one capable of indicating an absolute position along the scale.

Inductive position encoder utilizing slanted scale pattern

Inductive position encoder utilizing transmissive configuration

An inductive position encoder includes a scale, a detector and a signal processor. The scale includes a periodic pattern of signal modulating elements (SME) arranged along a measuring axis (MA) with a spatial wavelength W. The detector comprises sensing elements and a field generating coil that generates a changing magnetic flux. The sensing elements comprise conductive loops that provide detector signals responsive to a local effect on the changing magnetic flux provided by adjacent SME's. Some or all of the conductive loops are configured according to an intra-loop shift relationship wherein equal 'shifted proportions' of a loop are shifted in opposite directions by W/4K. K is an odd integer. The intra-loop shift relationship can be used to suppress Kth spatial harmonic components in the detector signals, while also overcoming longstanding detrimental layout problems. It combines easily with 'loop width' spatial filtering techniques that filter other spatial harmonic signal components.

Sensing winding configuration for inductive position encoder

A pitch compensated inductive position encoder includes a scale comprising first and second tracks including periodic patterns having a wavelength W, a detector, and signal processing. The second track pattern may be shifted along the measuring direction by a pattern offset STO relative to the first track pattern. In the detector, first-track and second-track field generating coil portions generate fields in first and second interior areas aligned with the first and second pattern tracks, respectively. First and second sensing coil configurations that are aligned with the first and second tracks, respectively, are offset relative to one another by STO+/&#x2212;0.5*W along the measuring direction. In various embodiments, the first and second sensing coil configurations may have the same sequence of individual coil polarities if the generated field polarities are different, and may have inverted or opposite sequences if the generated field polarities are the same.

Winding and scale configuration for inductive position encoder

An electronic position encoder includes a scale and detector. The detector includes a field generating coil (FGC) having elongated portions (EPs) bounding a generated field area (GFA) aligned with sensing windings, to provide position signals responsive to the scale interacting with the generated field. Sensing elements and EPs are fabricated in 'front' layers of the detector. A transverse conductor portion (TCP) fabricated in a 'rear' layer connects the EP of the FGC via feedthroughs. A shield region in a layer between the front and rear layers intercepts at least a majority of a projection of the TCP toward the front layers to eliminate undesirable signal effects. The FGC feedthroughs generate GFC feedthrough stray fields. Feedthrough pairs that connect sensing winding signals to rear layers of the detector are specially configured to mitigate undesirable signal effects that may otherwise result from their coupling to the GFC feedthrough stray fields.

Transmitter and receiver configuration for inductive position encoder

An electronic position encoder includes a scale and detector. The detector includes a field generating coil (FGC) having elongated portion configurations (EPCs) bounding a generated field area (GFA) aligned with sensing elements in a sensing area, to provide position signals responsive to the scale interacting with the generated field. Sensing elements and EPCs are fabricated in 'front' layers of the detector portion. The EPCs include end gradient arrangements (EGAs) configured to reduce field strength in the generated field area as a function of position along the x-axis direction for positions approaching the end of the GFA. A shielded transverse conductor portion (TCP) fabricated in a 'rear' layer connects the EPCs and/or EGAs of the FGC via feedthroughs. A conductive shield region (CSR) configuration in a CSR layer between the front and rear layers intercepts at least a majority of a projection of the TCP toward the front layers.

An electronic position encoder includes a scale and a detector. The detector includes a field generating coil (FGC) having elongated portions bounding a generated field area, and a sensing area, both aligned along the scale. Sensing elements in the sensing area provide position signals responsive to the scale interacting with the generated field. Sensing elements and elongated portions are fabricated in 'front' layers of the detector portion. A crosswise shielded end section (SES) fabricated in a 'rear' layer connects the elongated portions via feedthroughs. The sensing element area is longer than the elongated portions of the FGC. A projection of the SES normal to the layers overlaps sensing elements in the sensing element area. A conductive shield region CSR is configured in a CSR layer interposed between the front and rear layers to intercept at least a majority of the projection of the SES toward the overlapped sensing elements.

An inductive position detector (IPD) for stylus position measurement in a scanning probe comprises a coil board configuration located along a central axis in the probe with a motion volume extending on opposite sides of the coil board configuration. The coil board configuration includes N top rotary sensing coils (RSCs) and a top axial sensing coil configuration (ASCC), and N bottom RSCs and a bottom ASCC. A pair of stylus-coupled conductive disruptors move along Z (axial) and X-Y (rotary) directions in the motion volume. A generating coil (GC) of the coil board configuration generates a changing magnetic flux (e.g., encompassing all or at least part of the disruptors), and coil signals indicate the disruptors and/or stylus positions. Areas of the conductive disruptors may be larger than an area of the generating coil in some implementations, and the conductive disruptors may each comprise a plurality of concentric conductive loops, spirals, etc.

Inductive position detection configuration for indicating a measurement device stylus position

An inductive position detector (IPD) for stylus position measurement in a scanning probe comprises two substrates located along a central axis in the probe with a motion volume therebetween, each including N rotary sensing coils (RSCs) and respective axial sensing coil configurations (ASCC). A stylus-coupled conductive disruptor moves along Z (axial) and X-Y (rotary) directions in the motion volume. A generating coil (GC) generates a changing magnetic flux encompassing the disruptor and coils, and coil signals indicate the disruptor and/or stylus position. Axial projection of the disruptor defines axial sensing overlap area (ASOA) with the ASCC, and rotary sensing overlap areas (RSOAs) with respective RSCs. The IPD is configured such that the ASOA is independent of disruptor position, and N complementary pairs (CPs) of RSCs are provided, wherein the magnitude of the change in the RSOA in the two coils of a CP is the same for any disruptor displacement.

An absolute position encoder comprises a scale and a detector overlaying the scale. The scale includes a periodic pattern of wavelength Wf and a code pattern having bit length Wcode. The detector includes a set of periodic pattern sensors and M sets of code pattern sensors. M is at least two. The configuration principles include: a) Wcode is larger than Wf and at most M*Wf, and b) the sets of code pattern sensors are located along the measuring axis at respective alignment positions configured such that as the code pattern moves in a single direction it moves by successive alignment intervals that are each at most Wf to align with successive alignment positions. Signal processing is provided to determine the absolute position based on the M respective sets of code detector signals and on spatially periodic signals arising in the periodic pattern sensing elements due to the periodic pattern.

Compact pseudorandom scale and read head for an inductive type absolute position encoder

An electronic position encoder includes a scale comprising first and second pattern tracks including respective signal modulating scale patterns, a detector and a signal processing configuration. The detector includes first-track and second-track field generating coil portions that surround first and second interior areas aligned with the first pattern track and second pattern track, respectively. The first-track and second-track field generating coil portions each include first and second elongated portions extending along the measuring axis direction, connected to end portions extending along a y-axis direction transverse to the measuring axis. The detector includes sensing elements that span across the first and second interior areas along the y-axis direction. A nominal y-axis trace width dimension of the elongated portions is at least 0.1 times a y-axis width of the first and/or second interior areas. In various implementations, a shielded end section may be used to connect the elongated portions.

An electronic position encoder includes a scale comprising a pattern track having a track width dimension along a y-axis direction that is perpendicular to an x-axis measuring axis direction, a detector, and a signal processing configuration. The detector includes a field generating coil configuration fixed on a multi-layer printed circuit board (PCB), including a field generating coil portion that surrounds an interior area aligned with the pattern track and includes first and second elongated portions having a trace width along the y-axis direction, which is at least 0.1 times a y-axis width of the interior area. The detector includes conductive receiver loops arranged along the x-axis direction and fixed on the PCB. The first and second elongated portions are fabricated using at least an interior copper layer of the PCB, and the conductive receiver loops are fabricated using at least one copper layer that is closer than the interior copper layer to a front surface of the detector that faces the scale pattern.

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Kirkland, WA, United States of America

Ted Staton Cook