GB2531257A - Compass sensor based angle encoder for a magnetic target ring - Google Patents
Compass sensor based angle encoder for a magnetic target ring Download PDFInfo
- Publication number
- GB2531257A GB2531257A GB1418055.8A GB201418055A GB2531257A GB 2531257 A GB2531257 A GB 2531257A GB 201418055 A GB201418055 A GB 201418055A GB 2531257 A GB2531257 A GB 2531257A
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- Prior art keywords
- ring
- angle encoder
- hall
- encoder according
- processing device
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
- G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
- G01D5/142—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage using Hall-effect devices
- G01D5/145—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage using Hall-effect devices influenced by the relative movement between the Hall device and magnetic fields
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/30—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring angles or tapers; for testing the alignment of axes
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
- G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
- G01D5/142—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage using Hall-effect devices
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
- G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
- G01R33/07—Hall effect devices
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
- G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
- G01R33/07—Hall effect devices
- G01R33/072—Constructional adaptation of the sensor to specific applications
- G01R33/075—Hall devices configured for spinning current measurements
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Transmission And Conversion Of Sensor Element Output (AREA)
Abstract
The invention relates to an angle encoder for use in bearing applications including a magnetic ring (14) with two or more poles configured to be fixed in rotation to a first ring (10) of a bearing and at least one Hall sensor (16a - 16c) configured to be fixed in rotation to a second ring (12) of the bearing, and a signal processing device (18) using the output of the at least one Hall sensor (16a - 16c) to determine the angle between the first ring (10) and the second ring (12) of the bearing. It is proposed that the Hall sensor (16a - 16c) is configured as a spinning-current Hall sensor.
Description
Compass sensor based angle encoder for a magnetic target ring
Background of the Invention
Common angle encoders used in bearings use a magnetic ring with two or more poles, a number of sensors around the circumference and an algorithm to find the angle between inner and outer ring of the bearings. The available sensors have limited the applicability terms of resolution, range, and size of the sensor area.
The resolution of the measurement of the magnetic field strength is limited by temperature-or deformation-induced varations of the offset-voltage. The range is limited by saturation of the field of high quality magnets on the one hand as well as by strong external fields that could not be sufficiently deflected.
Bearing assemblies including sensors for measuring the absolute position of one of the bearing rings with respect to the other bearing ring are known e.g. from the document WO 2007/077369 A2. The system comprises three magnetic sensors delivering sinusoidal signals in response to a magnetic field generated by a magnetic encoder ring and a subtraction module for processing the signals.
The active areas of Hall cells used in sensor bearings of the type described in W0 2007/077389 A2 need to be positioned very precisely relative to each other and relative to the pole surface of the magnetic multipolar encoder ring. Imprecision in the radial, axial or angular position of the active area of the Hall cells immediately affects the electric signal precision and therefore the precision of the position measurement.
A new class of digital output Hall sensors requiring small building space and having a resolution sufficient for sensing the magnetic field of the earth as well as a big dynamic range is disclosed in WO 2005/073744 Al. This document teaches a magnetic field sensor comprising at least two Hall plates, wherein the magnetic field sensor is equipped to generate measuring currents in a number of directions in the Hall plates and to measure a potential difference over the Hall plates in a plane direction of the Hall plate, wherein the direction is always essentially perpendicular to the direction of the measuring current and wherein the potential difference measured is a measure for the magnetic field through the Hall plate in a direction that is essentially perpendicular to the direction of the measuring current and the measured potential difference. The magnetic field sensor is equipped to generate a S measuring current in each Hall plate in preferably at least eight directions. The direction of the measuring current is periodically switched between the at least eight directions according to a predetermined sequence.
The sensors of this type are therefore referred to as "spinning-current" Hal sensors here and in the following.
Using two Hall plates and a driving method with spinning currents enables reducing the magnetic field offset and its variations below the required precision, which is at least one order of magnitude smaller than the earth's magnetic field of 30-5OpT in central Europe. Indeed, sensors as disclosed in WO 2005/073744 Al can be designed so as to have a sub-pT resolution.
The compass sensors as disclosed in WO 2005/073744 Al have been specifically designed to be small enough for inclusion in small electronic devices such as a OPS watch, and measure accurately the small earth magnetic field, even in the neighbor-hood of the steel of a car. However, the inclusion of this new class of sensors in applications other than compass and OPS devices, in particular in angle encoders, has never been envisaged.
Summary of the Invention
Angle encoder for use in bearing applications including a magnetic ring with two or S more poles configured to be fixed in rotation to a first ring of a bearing, and at least one Hall sensor configured to be fixed in rotation to a second ring of the bearing, and a signal processing device using the output of the at least one Hall sensor to determine the angle between the first ring and the second ring of the bearing.
It is proposed that the Hall sensor is configured as a spinning-current Hall sensor.
The invention overcomes the problems of the prior art by using a spinning-current Hall sensor as known from the field of modern compass sensors, preferably with a sub-microlesla resolution. The extreme resolution and big dynamic range, com-bined with near zero offset and its dynamic range that prevents saturation in the angle encoder bearing magnetic environment, makes it possible to improve the quality of the angle encoder and to open new possibilities for self-calibration, error detection, and detection of external magnetic fields.
The invention overcomes the technical prejudice that spinning current Hall sensors are not suitable for engineering applications usually requiring a high degree of robustness.
In a preferred embodiment of the invention, the angle encoder comprises at least three Hall sensors placed around the circumference of the second ring, which are preferably homogeneously distributed with essentially equidistant spacing around the circumference of the second ring.
Further, the at least one Hall sensor is preferably provided with means for offset compensation. The offset compensation enables precise measurement of small magnetic fields in the required sub-ii-Tesla range.
According to a further aspect of the invention, the at least one Hall sensor is equipped with a microcontroller with digital output. The digital output reduces signal distortions due to external magnetic fields in the bus system.
Further, it is proposed that the signal processing device is configured to read the magnetic field strength values of the at least three Hall sensors at the same time. As compared to sequential readouts, the influence of temporal variations or fluctuations of the external magnetic fields can be eliminated. As a consequence, the cross-calibration of sensors is not disturbed by such variations or fluctuations.
In a preferred embodiment of the invention, the signal processing device is config-ured to determine the minimum and maxmum signal strength of the magnetic field strength values over at least two periods, preferably three to five periods of the signals; calculate the offset of the respective signal as the difference between the maximum and the absolute value of the minimum strength of each signal; compare the offset to a predefined alarm threshold value and raising an alarm if the offset has passed the alarm threshold value. The offset value depends primarily on external magnetic fields, the presence of which may indicate that a motor or a generator nearby the angle encoder is defective.
Further, it is proposed that the signal processing device is configured to calculate the amplitude of the signal as the sum of the absolute value of the minimum signal strength and the maximum signal strength; and scale and normalize the signal value according to the computed amplitude. The scaling and normalizing of the signals eliminates the dependence on the distance between the sensors and the magnetic ring. The encoder is therefore very insensitive to mounting tolerances and operates even with large distances between the magnetic encoder ring and the sensors.
In a further aspect of the invention, it is proposed that the signal processing device is configured to verify if the values of the at least three scaled signals are at a distance of 1/3rd of a period of the sine wave and to correct the values accordingly to compensate an angular mounting deviation of one sensor. This correction may be achieved by adding a phase delay to the signal of the sensor with deviating position or by other suitable means.
It is further proposed that the signal processing device is configured to read the magnetic field strength values of the at least three Hall sensors; calculate an estimate for the magnetic field strength value of at least a first one of the at least three Hall sensors by extrapolating from or interpolating between magnetic field strength values of at least two Hall sensors other than the first one of the at least three Hall sensors; calculate a difference between the estimate and the magnetic field strength value measured by the first one of the at least three Hall sensors; and use the difference when processing the magnetic field strength value measured by the first one of the at least three Hall sensors. The difference is a measure for the reliability of the sensor, wherein the reliability decreases with increasing difference.
The difference therefore contains valuable information helping to monitor the proper functioning of the sensor.
In one aspect of the invention, it is proposed that the signal processing device is configured to calculate said difference for each of the at least three Hall sensors and to determine weight factors for the magnetic field strength values respectively, wherein the weight factors decrease with increasing difference and wherein the weight factors quantify the weight given to the corresponding magnetic field strength value when determining the angle between the first ring and the second ring of the bearing.
The signal processing device is configured to calculate said difference for each of the at least three Hall sensors, compare the difference to a threshold value respec-tively, and disregard the corresponding magnetic field strength value of one of the sensors when determining the angle between first ring and the second ring of the bearing when the difference pertaining to the one sensor exceeds the threshold value. Because of the high sensor accuracy a "limp home" mode using less sensors becomes feasible.
In a further aspect of the invention, it is proposed that the signal processing device is configured to calculate said difference for each of the at least three Hall sensors; compare the difference to an alarm threshold value respectively, and issue a warning signal when one of the differences exceeds the alarm threshold value.
The above description and the below description of the figures and the embodi-ments of the invention as well as the appended claims and figures contain multiple features of the invention in specific combination. The person skilled in the art will be able to combine these features in other suitable combinations or sub-combinations in order to find further embodiments of the invention as defined in the claims adapted to his or her specific needs.
Brief Description of the Figures
Fig. 1 is a schematic representation of the bearing equipped with an angle encoder according to the invention; and Fig. 2 is an overview of a processing flow implemented in a signal pro-cessing device of the angle encoder according to the invention.
Detailed Description of the Embodiments
Fig. 1 illustrates a bearing having a first ring formed as an outer ring 10 and a second ring formed as an inner ring 12, wherein a magnetic ring 14 with multiple poles is attached to the inner ring l2so as to rotate together with the inner ring 12.
Three Hall sensors 1 6a to 1 6c are attached to the outer ring 10 and are connected to inputs of a signal processing device 18 formed as a microcontroller via a bus system.
Each of the Hall sensors iSa to 16c is configured as a spinning-current Hall sensor comprising at least two essentially circular Hall plates equipped with suitable electrodes to generate measuring currents and bias voltages in at least eight directions of the Hall plates in order to measure magnetic fields perpendicular to the Hall plates. The direction of the current is switched by a signal processing device 18 according to a predetermined pattern and the directions of the currents in the two Hall plates of each sensor differ by a constant angle.
The Hall sensors 1 6a to 1 Sc are homogenously distributed with essentially equidis-tant spacing of approximately 120 degrees around the circumference of the outer ring 10.
The spinning current configuration enables an internal offset compensation of the Hall sensors 16a to 16c and the Hall sensors 16a to 16c are themselves equipped with a microcontroller (not illustrated) with digital output.
The digital outputs of the microcontrollers of the Hall sensors iSa to 16c are connected to the inputs of the signal processing device 18 reading the magnetic field strength values from this output. The magnetic field strength values are read at the same time and not sequentially as usual in the prior art.
In the step Si, the data processing device 18 converts the data received from the Hall sensors into 16 or 32 bit digital data. The data packets may include sensor identifiers and packet headers or the like which can be removed prior to processing.
In a step S2, the data processing device 18 carries out a moving average or other suitable low pass filtering procedure on the digital data and stores the minimum and maximum values over multiple periods, preferably three to five periods of the roughly sinusoidal signals.
After this, the offset of the signals pertaining to the different sensors is calculated as the difference between the maximum signal strength and the absolute value of the minimum signal strength and the offset is stored (Step S3).
The calculated offset is compared to a predetermined alarm threshold value by the signal processing device 18 which raises an alarm or re-calibrates the Hall sensors 16a to 16c if the offset has passed the alarm threshold value (Step 84).
Further, the amplitude of the signal is calculated as the sum of the absolute value of the minimum signal strength and the maximum signal strength and the signal values are scaled and normalized according to the computed amplitude (Step S5).
The signal processing device 18 then verifies if the at least three scaled signals pertaining to the different Hall sensors 16a to i6c are delayed by one third of a period of a sine wave. If this is not the case, the values are corrected accordingly (e.g. by adding a delay) to compensate for an angular mounting deviation of one of the Hal sensors 16a to lGc (Step S6).
Further, the signal processing device 18 cross-checks the function and reliability of the sensors 1 Ba to 1 6c by using the sensor outputs of the other Hall sen-sors 1 6a to 1 6c respectively. To this end. the signal processing device 18 calculates an estimate for the magnetic field strength value of each of the three Hall sen-sors 1 6a to 1 6c or interpolates the sensor values from the Hall sensors 1 6a to 1 6c other than the one for which the estimate is calculated (Step S7).
Then, the reliability of the Hall sensors 1 Ba to 1 6c is checked by comparing the thus calculated estimate with the actual measurement value. If the difference is too big,
B
i.e. bigger than a predetermined threshold value, the signal is identified as an outlier and disregarded or considered only with reduced weight as compared to the signals with higher quality when calculating the absolute angle between the first ring 10 and the second ring 12 of the bearing. Optionally, a warning signal can be issued or a corresponding entry into a storage medium can be made if one of the Hall sen-sors 1 6a to 1 6c is identified as defective by comparing the estimate with the actual measurement data.
Finally, the scaled and normalized signal values are multiplied with the weight factors determined based on the difference between the estimate and the sensor values and are input to an algorithm calculating the angle of rotation between the inner ring 10 and the outer ring 12 (Step SB).
Further, the data processing device may optionally compare the calculated offset values with pertinent threshold values and issue alarm signals or the like if a threshold value is exceeded. High offset values may indicate that excessive external magnetic fields exist, e.g. due to a defect in an electric motor or generator arranged in close proximity to the angle encoder according to the invention.
The scaling and normalizing of the signal value as described above results in the sensor unit continuously calibrating itself to compensate for aging and tolerances regarding the distance the magnetic target ring and the sensor. Indeed, due the high sensitivity of the spinning-current Hall sensor combined with the continuous re-calibration is impossible to use the sensors at high distances, i.e. with large gaps to the encoder ring and even outside of the metal environment housing the magnetic ring 14.
Claims (15)
- Claims 1. Angle encoder for use in bearing applications including a magnetic ring (14) with two or more poles configured to be fixed in rotation to a first ring (10) of a bearing and at least one Hall sensor (16a -16c) configured to be fixed in rotation to a second ring (12) of the bearing, and a signal processing device (18) using the output of the at least one Hall sensor (1 Ga -1 6c) to determine the angle between the first ring (10) and the second ring (12) of the bearing, characterized in that the Hall sensor (iSa -16c) is configured as a spinning-current Hall sensor.
- 2. Angle encoder according to claim 1, characterized by comprising at least three Hall sensors (lea -mc) placed around the circum-ference of the second ring (12).
- 3. Angle encoder according to claim 2, characterized in that the at least three Hall sensors (1 Ga -1 Sc) are homogeneously distributed with essentially equidistant spacing around the circumference of the second ring (12).
- 4. Angle encoder according to one of the preceding claims, characterized in that the at least one Hall sensor (1 Ga -1 Sc) is provided with means for offset compensation.
- 5. Angle encoder according to one of the preceding claims, characterized in that the at least one Hall sensor (isa -thc) is equipped with a microcontroller with digital output.
- 6. Angle encoder according to one of the preceding claims, characterized in that the signal processing device (18) is configured to read the magnetic field strength values of at least one of the three Hall sensors (iSa -1 Sc) at the same time.
- 7. Angle encoder according to claim 6, characterized in that the signal processing device (18) is configured to: a. determine the minimum and maximum signal strength of the magnet-ic field strength values over at least two periods of the signals; and b. calculate the offset of the respective signal as the difference between the maximum and the absolute value of the minimum strength of each signal.
- 8. Angle encoder according to claim 7, characterized in that the signal processing device (18) is configured to compare the offset to a is predefined alarm threshold value and to raise an alarm if the offset has passed the alarm threshold value.
- 9. Angle encoder according to claim 6, 7 orB, characterized in that the signal processing device (18) is configured to: a. calculate the amplitude of the signal as the sum of the absolute value of the minimum signal strength and the maximum signal strength; and b. scale and normalize the signal value according to the computed am-plitude.
- 10. Angle encoder according to claim 9, characterized in that the signal processing device (18) is configured to verify if the values of the at least three scaled signals are at a distance of 1/3rd of a period of the sine wave and to correct the values accordingly to compensate an angular mounting deviation of one sensor (isa -16c).
- 11. Angle encoder according to one of the preceding claims, characterized in that the signal processing device (18) is configured to: a. read the magnetic field strength values of the at least three Hall sen-sors (iSa -16c); b. calculate an estimate for the magnetic field strength value of at least a first one of the at least three Hall sensors (1 6a -1 6c) by extrapolat-ing from or interpolating between magnetic field strength values of at least two Hall sensors (1 6a -1 6c) other than the first one of the at least three Hall sensors (iSa -16c); c. calculate a difference between the estimate and the magnetic field strength value measured by the first one of the at least three Hall sensors (iSa -iSc); and d. use the difference when processing the magnetic field strength value measured by the first one of the at least three Hall sensors (isa -16c).
- 12. Angle encoder according to claim 11, characterized in that the signal processing device (18) is configured to calculate said difference for each of the at least three Hall sensors (1 Ga -1 Sc) and to determine weight factors for the magnetic field strength values respectively, wherein the weight factors decrease with increasing difference and wherein the weight factors quantify the weight given to the corresponding magnetic field strength value when determining the angle between the first ring (10) and the second ring (12) of the bearing.
- 13. Angle encoder according to claim 12, characterized in that the signal processing device (18) is configured to: a. calculate said difference for each of the at least three Hall sen-sors (lea -iSc); b. compare the difference to a threshold value respectively; and c. disregard the corresponding magnetic field strength value when de-termining the angle between the first ring (10) and the second ring (12) of the bearing when the difference exceeds the threshold value.
- 14. Angle encoder according to one of claims 11 -13, characterized in that the signal processing device (18) is configured to: a. calculate said difference for each of the at least three Hall sen-sors(16a-16c); b. compare the difference to an alarm threshold value respectively; and c. issue a warning signal when one of the differences exceeds the alarm threshold value.
- 15. Angle encoder according to one of the preceding claims, characterized in that the magnetic ring (14) is configured to be placed in a metal environment and in that the at least one Hall sensor (1 6a -1 6c) is placed outside said metal environment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1418055.8A GB2531257A (en) | 2014-10-13 | 2014-10-13 | Compass sensor based angle encoder for a magnetic target ring |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1418055.8A GB2531257A (en) | 2014-10-13 | 2014-10-13 | Compass sensor based angle encoder for a magnetic target ring |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB201418055D0 GB201418055D0 (en) | 2014-11-26 |
| GB2531257A true GB2531257A (en) | 2016-04-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| GB1418055.8A Withdrawn GB2531257A (en) | 2014-10-13 | 2014-10-13 | Compass sensor based angle encoder for a magnetic target ring |
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| GB (1) | GB2531257A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110657824A (en) * | 2018-06-29 | 2020-01-07 | 许弘裕 | Magnetic induction encoding device |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102019218270A1 (en) * | 2018-12-11 | 2020-06-18 | Aktiebolaget Skf | A system and method for determining angular displacement, speed and acceleration of a rotating member attached to a platform |
| CN115979312B (en) * | 2022-11-24 | 2023-08-01 | 哈尔滨理工大学 | Electromagnetic encoder angle value jump point suppression method and device based on ant colony algorithm |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2050627A (en) * | 1979-05-16 | 1981-01-07 | Ransome Hoffmann Pollard | Improvements in mechanical assemblies employing sensing means for sensing motion or position |
| WO2005073744A1 (en) * | 2003-12-19 | 2005-08-11 | Xensor Integration B.V. | Magnetic field sensor, support for such a magnetic field sensor and a compass provided with such a magnetic field sensor |
| US20090219016A1 (en) * | 2006-01-06 | 2009-09-03 | Franck Debrailly | System for Detecting an Absolute Angular Position by Differential Comparison, Rolling Bearing and Rotary Machine |
| WO2012025778A1 (en) * | 2010-08-24 | 2012-03-01 | Aktiebolaget Skf (Publ) | A method and a system for determining the angular position of a rotary element, and a bearing including such a system |
| US20120218018A1 (en) * | 2011-02-25 | 2012-08-30 | Allegro Microsystems, Inc. | Circuit and method for processing signals generated by a plurality of sensors |
| US20120229123A1 (en) * | 2011-03-09 | 2012-09-13 | Chi-Yuan Cheng | Magnetic ring encoding device for composite signals |
| US20140225597A1 (en) * | 2013-02-13 | 2014-08-14 | Hernan D. Romero | Magnetic Field Sensor and Related Techniques That Provide an Angle Correction Module |
| JP2014167422A (en) * | 2013-02-28 | 2014-09-11 | Asahi Kasei Electronics Co Ltd | Hall electromotive force signal detection circuit and current sensor thereof |
| US20140266182A1 (en) * | 2013-03-14 | 2014-09-18 | Robert Bosch Gmbh | Vertical Hall Effect Sensor with Offset Reduction |
-
2014
- 2014-10-13 GB GB1418055.8A patent/GB2531257A/en not_active Withdrawn
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2050627A (en) * | 1979-05-16 | 1981-01-07 | Ransome Hoffmann Pollard | Improvements in mechanical assemblies employing sensing means for sensing motion or position |
| WO2005073744A1 (en) * | 2003-12-19 | 2005-08-11 | Xensor Integration B.V. | Magnetic field sensor, support for such a magnetic field sensor and a compass provided with such a magnetic field sensor |
| US20090219016A1 (en) * | 2006-01-06 | 2009-09-03 | Franck Debrailly | System for Detecting an Absolute Angular Position by Differential Comparison, Rolling Bearing and Rotary Machine |
| WO2012025778A1 (en) * | 2010-08-24 | 2012-03-01 | Aktiebolaget Skf (Publ) | A method and a system for determining the angular position of a rotary element, and a bearing including such a system |
| US20120218018A1 (en) * | 2011-02-25 | 2012-08-30 | Allegro Microsystems, Inc. | Circuit and method for processing signals generated by a plurality of sensors |
| US20120229123A1 (en) * | 2011-03-09 | 2012-09-13 | Chi-Yuan Cheng | Magnetic ring encoding device for composite signals |
| US20140225597A1 (en) * | 2013-02-13 | 2014-08-14 | Hernan D. Romero | Magnetic Field Sensor and Related Techniques That Provide an Angle Correction Module |
| JP2014167422A (en) * | 2013-02-28 | 2014-09-11 | Asahi Kasei Electronics Co Ltd | Hall electromotive force signal detection circuit and current sensor thereof |
| US20140266182A1 (en) * | 2013-03-14 | 2014-09-18 | Robert Bosch Gmbh | Vertical Hall Effect Sensor with Offset Reduction |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110657824A (en) * | 2018-06-29 | 2020-01-07 | 许弘裕 | Magnetic induction encoding device |
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| Publication number | Publication date |
|---|---|
| GB201418055D0 (en) | 2014-11-26 |
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