WO2014106471A1 - 一种适用于角度磁编码器的永磁体 - Google Patents

一种适用于角度磁编码器的永磁体 Download PDF

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Publication number
WO2014106471A1
WO2014106471A1 PCT/CN2014/070086 CN2014070086W WO2014106471A1 WO 2014106471 A1 WO2014106471 A1 WO 2014106471A1 CN 2014070086 W CN2014070086 W CN 2014070086W WO 2014106471 A1 WO2014106471 A1 WO 2014106471A1
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Prior art keywords
permanent magnet
magnetic field
magnetic encoder
encoder according
phase angle
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PCT/CN2014/070086
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English (en)
French (fr)
Inventor
迪克·詹姆斯·G
周志敏
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江苏多维科技有限公司
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Application filed by 江苏多维科技有限公司 filed Critical 江苏多维科技有限公司
Priority to US14/758,447 priority Critical patent/US9715959B2/en
Priority to JP2015551115A priority patent/JP6438889B2/ja
Priority to EP14735222.3A priority patent/EP2942794B1/en
Publication of WO2014106471A1 publication Critical patent/WO2014106471A1/zh

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/02—Permanent magnets [PM]
    • H01F7/0205—Magnetic circuits with PM in general
    • H01F7/021—Construction of PM
    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
    • H01F1/047—Alloys characterised by their composition
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
    • H01F1/047—Alloys characterised by their composition
    • H01F1/053—Alloys characterised by their composition containing rare earth metals
    • H01F1/055—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
    • H01F1/0551—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 in the form of particles, e.g. rapid quenched powders or ribbon flakes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
    • H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
    • H01F1/06—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/02—Permanent magnets [PM]
    • H01F7/0273—Magnetic circuits with PM for magnetic field generation
    • H01F7/0289—Transducers, loudspeakers, moving coil arrangements

Definitions

  • the invention relates to a permanent magnet in the field of measurement technology, in particular to a permanent magnet suitable for an angular magnetic encoder, an angular magnetic encoder comprising the permanent magnet and an electronic water meter.
  • the photoelectric coding technology can realize direct reading and measurement of the digital counting wheel code, and does not need to be accumulated, thereby being widely used.
  • this technology generally has a carry-on error phenomenon, and has poor anti-interference ability to bubbles, glare, dirt, leakage and the like.
  • the angular magnetic coding technology has higher resolution, no carry error phenomenon, good stability, and can completely eradicate various kinds of bad faults caused by photoelectric technology, and becomes an alternative coding technique for photoelectric coding.
  • the angular magnetic coding technique obtains the measurement reading by encoding the digital counting wheel.
  • the principle is to use a magnetoresistive sensor such as a tunnel magnetoresistive angular displacement sensor to sense the rotating magnetic field phase of the annular permanent magnet mounted on the digital counting wheel.
  • a magnetoresistive sensor such as a tunnel magnetoresistive angular displacement sensor to sense the rotating magnetic field phase of the annular permanent magnet mounted on the digital counting wheel.
  • the measurement accuracy of the angular magnetic coding technique depends on the performance characteristics of the two components of the magnetic-sensitive angular displacement sensor and the permanent magnet.
  • magnetoresistive sensors such as tunnel magnetoresistive sensors have higher magnetic field sensitivity, and their power consumption and size can be greatly reduced.
  • the tunnel magnetoresistive angular displacement sensor comprises two mutually orthogonal tunnel magnetoresistive sensors.
  • the two sine and cosine outputs formed by the tunnel magnetoresistive angular displacement sensor and the phase angle of the rotating magnetic field formed by the permanent magnet detecting magnetic field component, that is, the magnetic field generated by the permanent magnet in the detecting surface and the sensitive axis of the tunnel magnetoresistive sensor ⁇ , also referred to herein as the phase angle of the detected magnetic field, is related as follows:
  • the phase angle of the rotating magnetic field can be calculated from the output of the tunnel magnetoresistive angular displacement sensor OUT1 and OUT2. Angle:
  • ⁇ ATAN ( OUT2/OUT1 ).
  • the rotational phase angle ⁇ of the permanent magnet during the rotation is defined as the position vector point r of the permanent magnet in the course of the rotation through the tunnel magnetoresistive sensor.
  • the phase angle of the permanent magnet detects the magnetic field component causing the tunnel magnetoresistive sensor to induce.
  • the permanent magnet rotation phase angle ⁇ and the rotating magnetic field phase angle ⁇ form a linear relationship, satisfying 0 ⁇ 360
  • the phase relationship between the phase angle ⁇ of the rotating magnetic field detected by the tunnel magnetoresistive sensor and the rotational phase angle ⁇ of the permanent magnet can be correlated.
  • the tunnel magnetoresistive angle magnetic encoder technology has special requirements for the design performance of permanent magnets when applied to electronic water meters, and the permanent magnets used in the existing angle magnetic encoders have the following disadvantages:
  • the existing angular magnetic encoder mostly uses a Hall sensor as an angle sensor, and the corresponding detection magnetic field component is a magnetic field generated by the permanent magnet perpendicular to the detection surface component, and the detection magnetic field component corresponding to the tunnel magnetoresistive sensor is a magnetic field detection.
  • the in-plane component so the permanent magnet of the existing angular magnetic encoder cannot meet the requirements of the magnetic field measurement of the tunnel magnetoresistive sensor.
  • the existing angular magnetic encoder permanent magnets generally adopt a solid cylindrical design, and the electronic water meter is to minimize the installation space, and the permanent magnets are required to be circularly arranged to be directly mounted on the runner.
  • the object of the present invention is to overcome the above-mentioned shortcomings in the prior art, and to provide a permanent magnet suitable for an angular magnetic encoder, which can be mounted on an electronic water meter runner, save installation space, and can meet the tunnel magnetoresistive sensor.
  • the phase angle of the rotating magnetic field between the magnetic field components in the detection plane The linear relationship between ⁇ and the rotational phase angle ⁇ of the permanent magnet increases the measurement accuracy of the angular magnetic encoder.
  • a permanent magnet suitable for an angular magnetic encoder having a columnar annular structure including a first permanent magnet unit and a second permanent magnet unit, the first permanent magnet unit and The second permanent magnet unit is geometrically symmetrical with respect to the diameter section, and the diameter section is a section formed by the outer diameter and the axial length of the permanent magnet.
  • the magnetization of the first permanent magnet unit and the magnetization of the second permanent magnet unit are parallel to the axial direction of the cylindrical ring and are opposite in direction, or
  • the magnetization of the first permanent magnet unit and the magnetization of the second permanent magnet unit are perpendicular to the diameter section, and the directions are parallel.
  • the magnetization of the first permanent magnet unit and the magnetization of the second permanent magnet unit are the same.
  • the permanent magnet columnar ring structure has an outer diameter of 3-200 mm.
  • the permanent magnet columnar ring structure has an inner diameter of 1-100 mm.
  • the permanent magnet columnar ring structure has an axial length of 1-50 mm.
  • the detecting surface corresponding to the permanent magnet is located in front of the cylindrical annular end surface and parallel to the bottom surface.
  • the distance between the detecting surface and the end surface of the columnar ring is 1-5 mm.
  • the detected magnetic field component corresponding to the permanent magnet is a component of the magnetic field in the detection plane.
  • the specific detection area is located in a region of the detection plane that is within a specific radius of the cylindrical ring axis, and the rotational phase angle of the detected magnetic field component and the rotational phase angle of the permanent magnet have a linear variation characteristic in the specific detection area.
  • the constituent material of the permanent magnet is Alnico.
  • the constituent material of the permanent magnet is a ferrite ceramic material MO ⁇ 6Fe 2 O 3 , M is Ba, Sr or a combination of the two.
  • the constituent material of the permanent magnet is one or more selected from the group consisting of FeCrCo alloy and NbFeB alloy.
  • the permanent magnet is a composite of a powder of a constituent material of the permanent magnet and a plastic, rubber or resin.
  • the columnar circular permanent magnet used in the invention has a simple structure and can be directly embedded in the digital wheel of the water meter to reduce the requirement for the installation space.
  • the columnar circular permanent magnet used in the present invention comprises two simple permanent magnet units, and the magnetization configuration is simple and easy to implement.
  • the cylindrical annular permanent magnet used in the present invention has a specific detection region having a linear relationship between the rotational phase angle of the detected magnetic field component and the rotational phase angle of the permanent magnet in the detecting surface, and satisfies the measurement requirement of the tunnel magnetoresistive sensor.
  • the cylindrical annular permanent magnet used in the invention has a distance between the detecting surface and the end surface, and the distance between the specific detecting area and the axial center in the detecting surface can be varied within a wide range, so that the installation space of the tunnel magnetoresistive sensor is flexible.
  • the magnetic encoder and the electronic water meter according to the present invention have a small volume and high measurement accuracy.
  • Figure 1 is a top plan view of a permanent magnet according to Embodiment 1 of the present invention.
  • Figure 2 is a front view of the permanent magnet shown in Figure 1.
  • Figure 3 is a top plan view of a permanent magnet according to Embodiment 2 of the present invention.
  • Figure 4 is a front view of the permanent magnet shown in Figure 3.
  • Figure 5 is a top plan view of the mounting position of the permanent magnet relative to the tunnel magnetoresistive sensor in accordance with the present invention.
  • Figure 6 is a side elevational view of the mounting position of the permanent magnet relative to the tunnel magnetoresistive sensor in accordance with the present invention.
  • Fig. 7 is a three-dimensional magnetic field vector distribution diagram of the permanent magnet of the first embodiment in the detection plane.
  • Fig. 8 is a view showing a phase angle of a rotating magnetic field ⁇ and a rotational phase angle of a permanent magnet for detecting a magnetic field component in the permanent magnet detecting surface of the first embodiment Typical linear relationship diagram.
  • Fig. 9 is a view showing the phase angle of the rotating magnetic field ⁇ and the rotational phase angle of the permanent magnet of the magnetic field component detected by the permanent magnet in the embodiment 1.
  • Figure 10 is a diagram showing the phase angle of the rotating magnetic field ⁇ and the rotational phase angle of the permanent magnet for detecting the magnetic field component in the permanent magnet detecting surface of the first embodiment. A graph of the relationship between linear and nonlinear.
  • Figure 11 shows the magnetic field amplitude of the magnetic field component Bx-y and the rotational phase angle of the permanent magnet in the permanent magnet detection plane of the first embodiment. relation chart.
  • a linear fitting parameter R 2 for detecting a relationship between a rotating magnetic field phase angle ⁇ of a magnetic field component and a rotational phase angle ⁇ of a permanent magnet in the permanent magnet detecting surface of Embodiment 1, and a relative position r/Ro of the tunnel magnetoresistive sensor from the axial center. relation chart.
  • Figure 13 is a diagram showing the relative magnetic field amplitude of the magnetic field component and the distance from the axis of the tunnel magnetoresistive sensor in the permanent magnet detecting surface of the first embodiment. r/Ro diagram.
  • Fig. 14 is a three-dimensional magnetic field vector distribution diagram of the permanent magnet of the second embodiment in the detection plane.
  • Figure 15 is a diagram showing the phase angle of the rotating magnetic field ⁇ and the rotational phase angle of the permanent magnet for detecting the magnetic field component in the permanent magnet detecting surface of the second embodiment. Typical linear relationship diagram.
  • Figure 16 is a diagram showing the phase angle of the rotating magnetic field ⁇ and the rotational phase angle of the permanent magnet for detecting the magnetic field component in the permanent magnet detecting surface of the embodiment 2. Nonlinear relationship diagram.
  • Figure 17 is a diagram showing the phase angle of the rotating magnetic field ⁇ and the rotational phase angle of the permanent magnet of the rotating magnetic field component of the permanent magnet detected in Example 2. A graph of the relationship between linear and nonlinear.
  • Figure 18 is a diagram showing the magnetic field amplitude of the magnetic field component detected by the permanent magnet in the second embodiment. Bx-y and the rotational phase angle of the permanent magnet ⁇ relation chart.
  • Figure 20 is a diagram showing the relative magnetic field amplitude of the magnetic field component and the distance from the axis of the tunnel magnetoresistive sensor in the permanent magnet detecting surface of the second embodiment. r/Ro diagram.
  • Figure 21 is a schematic diagram of the structure of an electronic water meter.
  • FIG. 1 and 2 schematically show schematic views of a permanent magnet 100 according to Embodiment 1 of the present invention.
  • Permanent magnet 100 The cylindrical ring geometry includes a permanent magnet unit 101 and a permanent magnet unit 102, and the permanent magnet unit 101 and the permanent magnet unit 102 are geometrically symmetric with a diameter section 110.
  • Permanent magnet unit 101 The magnetization 103 and the magnetization 104 of the permanent magnet unit 102 are anti-parallel in the direction of the axis.
  • the magnetization 103 of the permanent magnet 101 and the magnetization of the permanent magnet unit 102 104 is the same size.
  • the size of the permanent magnet 100 can design the size of the permanent magnet 100 as needed.
  • the inner diameter of the cylindrical ring of the permanent magnet 100 is 1-100mm
  • the outer diameter of the cylindrical ring is 3-200 mm
  • the axial length of the cylindrical ring is 1-50 mm.
  • the detecting surface 120 corresponding to the permanent magnet 100 is located in front of the cylindrical annular end surface and parallel to the end surface. Preferably, the detecting surface 120 The distance from the end face of the cylindrical ring is 1-5 mm.
  • the detected magnetic field component 121 corresponding to the permanent magnet 100 is a component of the magnetic field generated by the permanent magnet in the detecting surface 120.
  • the detection surface The specific detection area 122 corresponding to 120 is located in a region of a specific radius from the axis of the cylindrical ring, in which the rotational phase angle of the magnetic field component 121 and the permanent magnet 100 are detected.
  • the rotational phase angle has a linear variation characteristic, which will be described in detail below.
  • the constituent material of the permanent magnet 100 is Alnico.
  • the constituent material of the permanent magnet 100 is a ferrite ceramic material MO ⁇ 6Fe 2 O 3 , M is Ba, Sr or a combination of both.
  • the constituent material of the permanent magnet 100 is a FeCrCo alloy or an NbFeB alloy.
  • the permanent magnet 100 is a composite of a powder of a constituent material of the permanent magnet 100 and a plastic, a rubber or a resin.
  • Permanent magnet 300 It is a cylindrical ring geometry comprising a permanent magnet unit 301 and a permanent magnet unit 302, and the permanent magnet unit 301 and the permanent magnet unit 302 are geometrically symmetric with a diameter section 310.
  • Permanent magnet unit 301 The magnetization 303 and the magnetization 304 of the permanent magnet unit 302 are parallel in a direction perpendicular to the diameter cross section.
  • the magnetization 303 and the permanent magnet unit 302 of the permanent magnet unit 301 The magnetization 304 is the same size.
  • the size of the permanent magnet 300 can design the size of the permanent magnet 300 as needed.
  • the inner diameter of the cylindrical ring of the permanent magnet 300 is 1-100mm
  • the outer diameter of the cylindrical ring is 3-200 mm
  • the axial length of the cylindrical ring is 1-50 mm.
  • the detecting surface 320 corresponding to the permanent magnet 300 is located in front of the end surface of the cylindrical ring and is parallel to the end surface. Preferably, the detecting surface 320 The distance from the end face of the cylindrical ring is 1-5 mm.
  • the detected magnetic field component 321 corresponding to the permanent magnet 300 is a component of the magnetic field generated by the permanent magnet in the detecting surface 320.
  • the detection surface A specific detection area 322 corresponding to 320 is located in a region from a specific radius of the axis of the cylindrical ring in which the rotational phase angle of the magnetic field component 321 and the permanent magnet 300 are detected.
  • the rotational phase angle has a linear variation characteristic, which will be described in detail below.
  • the constituent material of the permanent magnet 300 is Alnico.
  • the constituent material of the permanent magnet 300 is a ferrite ceramic material MO ⁇ 6Fe 2 O 3 , M is Ba, Sr or a combination of both.
  • the constituent material of the permanent magnet 300 is a FeCrCo alloy or an NbFeB alloy.
  • the permanent magnet 300 is a composite of a powder of a constituent material of the permanent magnet 300 and a plastic, a rubber or a resin.
  • Embodiment 3 is an angle magnetic encoder according to the present invention, including The digital wheel can be rotated around the axis, the permanent magnets embedded in the digital wheel, the tunnel magnetoresistive sensor and the digital processing circuit.
  • the permanent magnet is a permanent magnet according to the invention.
  • the tunnel magnetoresistive sensor is located on the permanent magnet detecting surface for sensing a component of the magnetic field generated by the permanent magnet in the detecting surface and outputting a sensing signal.
  • the tunnel magnetoresistive sensor is disposed in a region of the detection surface of the permanent magnet within a specific radius range of the axis of the permanent magnet columnar ring, and the component of the magnetic field generated by the permanent magnet in the detection plane is within the region of the specific radius
  • Rotational magnetic field phase angle ⁇ has a linear relationship with the rotational phase angle ⁇ of the permanent magnet.
  • a digital processing circuit is operative to calculate and output a code characterizing the rotational angle of the permanent magnet based on the sensed signal from the tunnel magnetoresistive sensor.
  • Figures 5 and 6 are the permanent magnets 100, 300 and the tunnel magnetoresistive sensor 500 in the third embodiment, respectively.
  • X-Y is established in the detecting faces 120, 320 with the permanent magnet axis as the origin
  • the coordinate system is shown in Figure 5. It is assumed that the inner radius of the cylindrical ring of the permanent magnets 100, 300 is Ri, the outer radius is Ro, and the thickness is t, and the tunnel magnetoresistive sensor 500 is on the detecting surface 120.
  • the position vector in 320 is r(x, y) whose azimuth is ⁇ with respect to the X axis. Assume that the detected magnetic field component at r is Bx-y(Bx , By) and the azimuth angle is ⁇ .
  • the relationship between angle ⁇ and angle ⁇ is as follows:
  • ⁇ and ⁇ vary between (-180 0 , 180 0 ).
  • the tunnel magnetoresistive sensor 500 When the angular magnetic encoder is operating, the tunnel magnetoresistive sensor 500 remains fixed while the permanent magnets 100, 300 Rotating around the axis, the point in the detection plane is centered on the origin, and the point on the circle where r is the radius passes through the tunnel magnetoresistive sensor 500 in sequence, and generates a rotating magnetic field whose phase and amplitude are passed by the tunnel magnetoresistive sensor 500. Measured. This is equivalent to the permanent magnets 100, 300 remaining fixed, and the tunnel magnetoresistive sensor 500 is sequentially translated to different points on the circumference and the detection magnetic field is measured. At this time, the permanent magnet rotation phase angle is ⁇ And the phase angle of the rotating magnetic field is ⁇ .
  • FIG. 7 is a three-dimensional magnetic field vector diagram of the permanent magnet 100 on the detecting plane 120.
  • the relationship between the phase angle ⁇ and the rotational phase angle ⁇ of the permanent magnet may be a linear relationship, a nonlinear relationship or a relationship characteristic between linear and nonlinear.
  • the curve 18 shown in Fig. 8 is a typical linear relationship between the rotating magnetic field phase angle ⁇ and the permanent magnet rotating phase angle ⁇ .
  • the curve 19 shown in Fig. 9 is the rotating magnetic field phase angle ⁇ and the permanent magnet rotating phase angle ⁇ .
  • the typical nonlinear relationship that may occur between the curves 20 shown in Figure 10 is a linear and nonlinear relationship between the phase angle ⁇ of the rotating magnetic field and the rotational phase angle ⁇ of the permanent magnet.
  • Figure 11 is a plot of the relationship between the amplitude of the rotating magnetic field Bx-y and the angle of rotation ⁇ , curve 21. As seen from curve 21, the magnitude of the rotating magnetic field is a periodic W-shaped change, and its corresponding maximum and minimum values are B H , B L .
  • the fluctuation of the magnetic field amplitude of the permanent magnet during rotation is as small as possible to ensure that the sensor signal is not affected.
  • a linear function is used to fit the relationship between ⁇ and ⁇ as shown in Figures 8, 9, and 10, and the linear fitting parameter R 2 is calculated. The closer R 2 is to 1, the better the linearity.
  • the degree of magnetic field fluctuations shown by curve 21 can be characterized by the following relationship:
  • Figure 12 is a plot of the linear fit parameters R 2 and r/Ro. As can be seen from the curve 22, in the region 23, its value is close to 1, indicating that the phase angle ⁇ of the rotating magnetic field and the rotational phase angle ⁇ of the permanent magnet are close to a linear relationship in this region, so the region 23 is the tunnel magnetoresistive sensor in the permanent A specific detection area corresponding to the detection surface 120 of the magnet 100 is suitable for placing the tunnel magnetoresistive sensor 17 and is not suitable for placement of the tunnel magnetoresistive sensor 17 in the region 24.
  • Figure 13 shows the relative position of normalized B and tunnel magnetoresistive sensor 500 in the detection surface 120 r/Ro The relationship curve. As can be seen from the curve 25, the magnitude of the change in the magnetic field within the particular detection zone 23 is suitable for signal detection by the tunnel magnetoresistive sensor 17.
  • Embodiment 4 is another angle magnetic encoder according to the present invention, which is rotatable about an axis as embodied in Embodiment 2
  • Figure 14 is a three-dimensional magnetic field vector diagram of the permanent magnet 300 in the detection surface 320, through the two-dimensional magnetic field component in the detection plane 310
  • the Bx-y distribution characteristics are calculated to obtain a linear relationship between the phase angle ⁇ of the rotating magnetic field and the rotational phase angle ⁇ of the permanent magnet in the detection surface 320 as shown in Figs. 15, 16, 17 , the nonlinear relationship curve 27 and the relationship between the linear nonlinearities 28 .
  • the existence of the linear relationship curve 26 indicates that the permanent magnet 300 has a rotating magnetic field phase angle ⁇ on its detecting surface.
  • Figure 18 is a plot of the relationship between the amplitude of the rotating magnetic field Bx-y and the rotational phase angle of the permanent magnet. From the curve 29, the rotating magnetic field Bx-y follows the rotational phase angle ⁇ as a periodic M-shaped wave relationship.
  • the ⁇ - ⁇ relationship curves of the different relative position r/Ro values are fitted, and the linear fitting parameter R 2 curve shown in FIG. 19 is obtained, which can be obtained from the curve 30.
  • the specific detection area 31 in the detection surface 320 is suitable for the working area of the tunnel magnetoresistive sensor 500, while in the area 32 it is not suitable for placing the tunnel magnetoresistive sensor 500.
  • the variation range of the normalized B with the tunnel magnetoresistive sensor 500 relative position r/Ro relationship 33 in the specific detection region 31 is small with respect to the non-working region 32.
  • the detection planes 120 and 320 are Inside, there are specific detection areas 23 and 31 such that the tunnel magnetoresistive sensor 500 rotates the magnetic field phase angle ⁇ and the permanent magnet rotation phase angle in this area. There is a linear relationship between them, and the amplitude of the magnetic field fluctuations satisfies the requirements of the sensor. In this way, the angle of the rotating magnetic field measured by the tunnel magnetoresistive sensor can be changed into the rotation angle of the permanent magnet, and The digital processing circuit calculates and outputs a code that characterizes the rotation angle of the permanent magnet, and realizes angular encoding of the angular magnetic encoder.
  • the angular magnetic encoder according to the present invention can be applied to fields such as electronic water meters.
  • Figure 21 shows the structure of an electronic water meter with an angular magnetic encoder with permanent magnets 100 or 300 installed.
  • the permanent magnet and the angular magnetic encoder of the embodiment 4 describe an electronic water meter according to the present invention.
  • the electronic water meter includes a central shaft and at least one angular magnetic encoder.
  • the angular encoders arranged in sequence have a determined number of revolutions between the axes of rotation.
  • the permanent magnet 100 is a columnar ring structure including a permanent magnet unit 101 and a permanent magnet unit 102, and is opposite to the diameter section 110 Geometrically symmetrical, the corresponding magnetizations 103 and 104 of the permanent magnet unit 101 and the permanent magnet unit 102 are anti-parallel in the axial direction and of the same size.
  • the permanent magnet 100 has an outer diameter of 3-20 mm and an inner diameter of 1 -15 mm.
  • the axial length is 1.5-10 mm
  • the permanent magnet 100 is mounted in the digital wheel 2001, the digital wheel rotates around the central axis 2003, and the tunnel magnetoresistive sensor 500 is mounted at a distance from the permanent magnet.
  • 100 End face 1-5 mm Detection surface 120 Distance axis r/Ro In the specific detection area 23, the phase angle of the rotating magnetic field that detects the magnetic field component in this specific detection area ⁇ It is linear with the rotation phase angle ⁇ of the permanent magnet.
  • the detected magnetic field component 121 is the component of the magnetic field within the detection surface 120.
  • Tunnel magnetoresistive sensor 500 is located on the board 2002 On the top, the signals at both ends are output through the board 2002.
  • the digital wheel 2001 is mounted on the center shaft 2003 and is fixed to the water meter rack together with the circuit board 2002 2004 On. Since the linear relationship between the rotational magnetic field phase angle ⁇ of the magnetic field component 121 and the permanent magnet phase angle ⁇ is detected, the phase angle of the rotating magnetic field measured according to the tunnel magnetoresistive sensor 500 can be ⁇ One-to-one correspondence with the permanent magnet phase angle ⁇ .
  • the angle of the rotating magnetic field measured by the tunnel magnetoresistive sensor can be changed into the rotation angle of the digital wheel, and
  • the digital processing circuit calculates and outputs a code that characterizes the angle of rotation of the digital wheel.
  • Different digital reels on each reel of each magnetic encoder are used to read different digits, each of which is 10:1 The number of revolutions.
  • the angular displacement of each digital wheel is the rotation phase angle ⁇ of the permanent magnet, and the permanent magnet 100 connected to the digital wheel can be connected through each tunnel magnetoresistive sensor 500.
  • the measurement of the rotating magnetic field is calculated.
  • the digital processing circuit processing on 2002 is shown in digital code form.
  • the electronic water meter reading can be directly displayed by reading the numbers corresponding to different digital wheels.
  • Permanent magnet 300 It is a cylindrical ring structure comprising a permanent magnet unit 301 and a permanent magnet unit 302, and is geometrically symmetrical with respect to the diameter section 310. Permanent magnet unit 301 and permanent magnet unit 302 The magnetizations are of the same magnitude and the directions are parallel to the direction perpendicular to the diameter section 310.
  • the permanent magnet 300 has an outer diameter of, for example, 5-20 mm, an inner diameter of 1-5 mm, and an axial length of 1-5 mm. .
  • the tunnel magnetoresistive sensor 500 is mounted in a specific detection area with a distance r/Ro from the detection surface 320 of the 1-5 mm end face of the permanent magnet 300. Within this particular detection region, the phase angle ⁇ of the rotating magnetic field that detects the magnetic field component is linear with the rotational phase angle ⁇ of the permanent magnet. Detecting the magnetic field component 321 is the magnetic field on the detection surface 320 The component inside. The detection process is similar to the electronic water meter using the permanent magnet 100, and will not be described here.

Abstract

一种适用于角度磁编码器的永磁体，该永磁体（100，300）具有柱状圆环结构，并包含第一永磁单元（101，301）和第二永磁单元（102，302），第一永磁单元（101，301）和第二永磁单元（102，302）相对于直径截面（110，310）几何对称，第一永磁单元（101，301）的磁化强度（103，303）和第二永磁单元（102，302）的磁化强度（104，304）平行于柱状圆环的轴向，且方向相反，或第一永磁单元（101，301）的磁化强度（103，303）和第二永磁单元（102，302）的磁化强度（104，304）垂直于所述直径截面（110，310），且方向平行一致。

Description

一种适用于角度磁编码器的永磁体
技术领域
本发明涉及的是一种测量技术领域的永磁体，具体是涉及一种适用于角度磁编码器的永磁体，包含该永磁体的角度磁编码器和电子水表。
背景技术
随着传感器技术的迅猛发展，传统的机械水表逐渐向新颖的电子水表过渡。在各种传感器技术中，光电编码技术可以实现数字计数转轮代码的直接读取计量，而且不需要累积，从而得到广泛应用。但该技术普遍存在进位误码现象，而且对气泡、强光、污垢、渗漏等因素的抗干扰能力差。 与光电编码技术相比，角度磁编码技术分辨率更高，无进位误码现象，稳定性好，而且可以完全根除光电技术引起的各种不良故障，成为一种可替代光电编码的编码技术。 角度磁编码技术通过对数字计数转轮进行编码来得到计量读数，其原理是利用磁阻传感器如隧道磁阻角位移传感器来感应安装在数字计数转轮上的环形永磁体的旋转磁场相位 来测量转轮的转角和位置，并采用电子技术转变成相应数字读数。
角度磁编码技术的测量精度取决于磁敏角位移传感器和永磁体两个组成部分的性能特征。与霍尔传感器相比，磁阻传感器如隧道磁阻传感器具有更高的磁场灵敏度，其功耗和尺寸也可大大降低。隧道磁阻角位移传感器包含两个相互正交的隧道磁阻传感器。隧道磁阻角位移传感器工作时形成的两个正弦和余弦输出与永磁体检测磁场分量即永磁体产生的磁场在检测面内的分量及隧道磁阻传感器敏感轴之间形成的旋转磁场相位角 φ ，本文中也称为探测磁场相位角，关系如下：
OUT1=COS （ φ ）
OUT2=SIN （ φ ）
利用反正切函数，就能根据隧道磁阻角位移传感器的输出 OUT1 和 OUT2 计算出旋转磁场相位角 φ 角度：
φ =ATAN （ OUT2/OUT1 ）。
永磁体在旋转过程中其旋转相位角 α ，定义为永磁体在旋转过程中依次经过隧道磁阻传感器的位置矢量点 r 的相位角，永磁体的检测磁场分量使隧道磁阻传感器产生感应。当永磁体旋转相位角 α 和旋转磁场相位角 φ 之间形成线性关系，满足在 0~360 °范围内一一对应时，就可以将隧道磁阻传感器所探测的旋转磁场相位角 φ 和永磁体旋转相位角 α 位置关系对应起来。例如为了能使 0-9 这 10 个代表数字在转轮的某一直径的圆周上以等间距角度增量间隔开，事先将 α 的范围划分成 10 个区间，每一区间用一个预期的数字表示。通过将永磁体角度进行编码，进而通过电子技术转化，可以实现水表读数的直接输出。
因此，隧道磁阻角度磁编码器技术在应用于电子水表时对于永磁体的设计性能将具有特殊要求，而现有的角度磁编码器采用的永磁体具有如下缺点：
（ 1 ）现有的角度磁编码器大都采用霍尔传感器作为角度传感器，其对应的检测磁场分量为永磁体产生的磁场垂直于检测面的分量，而隧道磁阻传感器对应的检测磁场分量为磁场在检测面内的分量，因此现有角度磁编码器的永磁体不能满足于隧道磁阻传感器磁场测量的要求。
（ 2 ）现有的角度磁编码器永磁体一般采用的是实心圆柱设计，而电子水表为尽量减少安装空间，要求永磁体为圆环形以便直接安装在转轮上。
发明内容
本发明的目的在于克服现有技术中存在的上述缺点，提供一种适用于角度磁编码器的永磁体，使之能够安装在电子水表转轮上，节省安装空间，并能够满足隧道磁阻传感器与检测面内磁场分量之间的旋转磁场相位角 φ 和永磁体旋转相位角 α 之间线性关系的要求，从而提高角度磁编码器的测量精度。
根据本发明的一个方面，提供一种适用于角度磁编码器的永磁体，该永磁体具有柱状圆环结构，包含第一永磁单元和第二永磁单元，所述第一永磁单元和第二永磁单元相对于直径截面几何对称，所述直径截面为所述永磁体的外直径与轴向长度所构成的截面，
所述第一永磁单元的 磁化强度 和第二永磁单元的磁化强度平行于柱状圆环的轴向，且方向相反，或
所述第一永磁单元的 磁化强度 和第二永磁单元的磁化强度垂直于所述直径截面，且方向平行一致。
优选地，所述第一永磁单元的 磁化强度 和第二永磁单元的磁化强度大小相同。
优选地，所述永磁体柱状圆环结构的外径为 3-200 mm 。
优选地，所述永磁体柱状圆环结构的内径为 1-100 mm 。
优选地，所述永磁体柱状圆环结构的轴向长度为 1-50 mm 。
优选地，所述永磁体所对应的检测面位于柱状圆环端面前方且平行于底面。
优选地，所述检测面与所述柱状圆环端面之间的距离为 1-5 mm 。
优选地，永磁体所对应的检测磁场分量为磁场在检测面内的分量。
优选地， 特定检测区域位于检测面内距离柱状圆环轴心特定半径范围的区域内，在该特定检测区域内检测磁场分量的旋转相位角和永磁体的旋转相位角具有线性变化特征 。
优选地，所述永磁体的组成材料为 Alnico 。
优选地，永磁体的组成材料为铁氧体陶瓷材料 MO·6Fe2O3 ， M 为 Ba ， Sr 或者两者的组合。
优选地，永磁体的组成材料为选自 RECo5 ，其中 RE=Sm 和 / 或 Pr ； RE2TM17 ，其中 RE=Sm ， TM=Fe ， Cu ， Co ， Zr 和 / 或 Hf ；以及 RE2TM14B ，其中 RE=Nd ， Pr 和 / 或 Dy ， TM=Fe 和 / 或 Co 中的一种或多种。
优选地，永磁体的组成材料为选自 FeCrCo 合金和 NbFeB 合金中的一种或多种。
更优选地，永磁体为所述永磁体的组成材料的粉末和塑料、橡胶或树脂形成的复合体。
本发明具有如下有益效果：
1 ）本发明采用的柱状圆环永磁体，结构简单，能够直接镶嵌在水表数字转轮内，减小对安装空间的要求。
2 ）本发明采用的柱状圆环永磁体，包含两个简单永磁单元，其磁化组态简单，易于实现。
3 ）本发明采用的柱状圆环永磁体，在检测面内存在检测磁场分量旋转相位角和永磁体旋转相位角之间具有线性关系的特定检测区域，满足隧道磁阻传感器的测量要求。
4 ）本发明采用的柱状圆环永磁体，检测面与端面距离，检测面内的特定检测区域与轴心的距离都可以在较大范围内变化，使得隧道磁阻传感器的安装空间较为灵活。
5 ）根据本发明的磁编码器和电子水表具有小的体积和高的测量精度。
附图说明
图 1 为根据本发明实施例 1 的永磁体的顶视图。
图 2 为图 1 所示永磁体的前视图。
图 3 为根据本发明实施例 2 的永磁体的顶视图。
图 4 为图 3 所示永磁体的前视图。
图 5 为根据本发明的永磁体相对于隧道磁阻传感器的安装位置顶视图。
图 6 为根据本发明的永磁体相对于隧道磁阻传感器的安装位置侧视图。
图 7 为实施例 1 的永磁体在检测面内的三维磁场矢量分布图。
图 8 为实施例 1 的永磁体检测面内检测磁场分量的旋转磁场相位角 φ 和永磁体旋转相位角 α 的典型线性关系图。
图 9 为实施例 1 的永磁体检测面内检测磁场分量的旋转磁场相位角 φ 和永磁体旋转相位角 α 的非线性关系曲线图。
图 10 为实施例 1 的永磁体检测面内检测磁场分量的旋转磁场相位角 φ 和永磁体旋转相位角 α 的介于线性和非线性之间的关系图。
图 11 为实施例 1 的永磁体检测面内检测磁场分量磁场幅度 Bx-y 和永磁体旋转相位角度 α 关系图。
图 12 为实施例 1 的永磁体检测面内，检测磁场分量的旋转磁场相位角 φ 和永磁体旋转相位角 α 关系的直线拟合参数 R2 与隧道磁阻传感器距离轴心相对位置 r/Ro 关系图。
图 13 为实施例 1 的永磁体检测面内，检测磁场分量的正则磁场幅度与隧道磁阻传感器距离轴心相对位置 r/Ro 关系图。
图 14 为实施例 2 的永磁体在检测面内的三维磁场矢量分布图。
图 15 为实施例 2 的永磁体检测面内检测磁场分量的旋转磁场相位角 φ 和永磁体旋转相位角 α 的典型线性关系图。
图 16 为实施例 2 的永磁体检测面内检测磁场分量的旋转磁场相位角 φ 和永磁体旋转相位角 α 的非线性关系图。
图 17 为实施例 2 的永磁体检测面内旋转磁场分量的旋转磁场相位角 φ 和永磁体旋转相位角 α 的介于线性和非线性之间的关系图。
图 18 为实施例 2 的永磁体检测面内检测磁场分量的磁场幅度 Bx-y 与永磁体旋转相位角度 α 关系图。
图 19 为实施例 2 的永磁体检测面内，检测磁场分量的旋转磁场相位角 φ 和永磁体旋转相位角 α 的直线拟合参数 R2 与隧道磁阻传感器距离轴心相对位置 r/Ro 的关系图。
图 20 为实施例 2 的永磁体检测面内，检测磁场分量的正则磁场幅度与隧道磁阻传感器距离轴心相对位置 r/Ro 关系图。
图 21 为电子水表结构示意图。
具体实施方式
下面将参照附图并结合具体实施例对本发明进行详细的说明。
实施例 1
图 1 和图 2 示意性示出根据本发明实施例 1 的永磁体 100 的示意图。永磁体 100 为柱状圆环几何结构，包含永磁单元 101 和永磁单元 102 ，永磁单元 101 和永磁单元 102 以直径截面 110 几何对称。永磁单元 101 的磁化强度 103 和永磁单元 102 的磁化强度 104 沿轴心方向反平行。优选的，所述永磁体 101 的磁化强度 103 和永磁单元 102 的磁化强度 104 大小相同。
本领域技术人员可以根据需要设计永磁体 100 的尺寸。优选的，永磁体 100 的柱状圆环的内径为 1-100mm ，柱状圆环的外径为 3-200 mm ，柱状圆环的轴向长度为 1-50 mm 。
永磁体 100 对应的检测面 120 位于柱状圆环端面前方且平行于端面。优选的，该检测面 120 与柱状圆环端面之间的距离为 1-5 mm 。本文中，永磁体 100 所对应的检测磁场分量 121 为永磁体产生的磁场在检测面 120 内的分量。本文中，检测面 120 内所对应的特定检测区域 122 位于距离柱状圆环轴心特定半径范围的区域内，在该特定检测区域内，检测磁场分量 121 的旋转相位角和永磁体 100 旋转相位角具有线性变化特征，这将在下文具体描述。
优选的，永磁体 100 的组成材料为 Alnico 。可替换地，永磁体 100 的组成材料为铁氧体陶瓷材料 MO·6Fe2O3 ， M 为 Ba ， Sr 或者两者的组合。可替换地，永磁体 100 的组成材料为 RECo5 ， RE=Sm 和 / 或 Pr ； RE2TM17 ， RE=Sm ， TM=Fe ， Cu ， Co ， Zr 和 / 或 Hf 以及 RE2TM14B ， RE=Nd ， Pr 和 / 或 Dy ， TM=Fe 和 / 或 Co 。可替换地，所述永磁体 100 的组成材料为 FeCrCo 合金或 NbFeB 合金。优选的，所述永磁体 100 为上述永磁体 100 的组成材料的粉末和塑料、橡胶或树脂等形成的复合体。
实施例 2
图 3 和图 4 示意性示出根据本发明实施例 2 的永磁体 300 的示意图。永磁体 300 为柱状圆环几何结构，包含永磁单元 301 和永磁单元 302 ，永磁单元 301 和永磁单元 302 以直径截面 310 几何对称。永磁单元 301 的磁化强度 303 和永磁单元 302 的磁化强度 304 沿垂直于直径截面方向平行一致。优选的，所述永磁单元 301 的磁化强度 303 和永磁单元 302 的磁化强度 304 大小相同。
本领域技术人员可以根据需要设计永磁体 300 的尺寸。优选的，永磁体 300 的柱状圆环的内径为 1-100mm ，柱状圆环的外径为 3-200 mm ，柱状圆环的轴向长度为 1-50 mm 。
永磁体 300 对应的检测面 320 位于柱状圆环端面前方且平行于端面。优选的，该检测面 320 与柱状圆环端面之间的距离为 1-5 mm 。本文中，永磁体 300 所对应的检测磁场分量 321 为永磁体产生的磁场在检测面 320 内的分量。本文中，检测面 320 内所对应的特定检测区域 322 位于距离柱状圆环轴心特定半径范围的区域内，在该特定检测区域内，检测磁场分量 321 的旋转相位角和永磁体 300 旋转相位角具有线性变化特征，这将在下文具体描述。
优选的，永磁体 300 的组成材料为 Alnico 。可替换地，永磁体 300 的组成材料为铁氧体陶瓷材料 MO·6Fe2O3 ， M 为 Ba ， Sr 或者两者的组合。可替换地，永磁体 300 的组成材料为 RECo5 ， RE=Sm ， Pr ，或 RE2TM17 ， RE=Sm ， TM=Fe ， Cu ， Co ， Zr ， Hf 以及 RE2TM14B ， RE=Nd ， Pr ， Dy ， TM=Fe ， Co 。可替换地，所述永磁体 300 的组成材料为 FeCrCo 合金或 NbFeB 合金。优选的，所述永磁体 300 为上述永磁体 300 的组成材料的粉末和塑料、橡胶或树脂等形成的复合体。
实施例 3
实施例 3 为根据本发明的一种角度磁编码器，包括 可绕轴旋转数字转轮，镶嵌在数字转轮中的永磁体，隧道磁阻传感器和数字处理电路。永磁体为根据本发明的永磁体。隧道磁阻传感器位于所述永磁体检测面上，用于感测所述永磁体产生的磁场在该检测面内的分量并输出感测信号。隧道磁阻传感器被布置在永磁体的检测面内距离永磁体柱状圆环轴心特定半径范围的区域内，在该特定半径范围的区域内，所述永磁体产生的磁场在检测面内的分量的旋转磁场相位角 φ 与永磁体旋转相位角 α 呈线性变化关系。数字处理电路用于根据来自所述隧道磁阻传感器的感测信号计算并输出表征所述永磁体旋转角度的代码。
图 5 和图 6 分别为实施例 3 中永磁体 100 ， 300 和隧道磁阻传感器 500 安装位置的顶视图和侧视图，检测面 120 ， 320 距离永磁体端面距离为 d 。以永磁体轴心为原点在检测面 120 ， 320 内建立 X-Y 坐标系统，如图 5 所示。假定永磁体 100 ， 300 的柱状圆环内半径为 Ri ，外半径为 Ro ，厚度为 t ，隧道磁阻传感器 500 在检测面 120 ， 320 内的位置矢量为 r(x ， y) ，其相对于 X 轴的方位角为 α 。假定 r 处的检测磁场分量 Bx-y(Bx ， By) 方位角度为 β 。角度 α 和角度 β 的计算关系如下：
Figure PCTCN2014070086-appb-I000001
， (x>0) ，
Figure PCTCN2014070086-appb-I000002
， (x<0 ， y>0) ，
Figure PCTCN2014070086-appb-I000003
， (x<0 ， y<0) ，
Figure PCTCN2014070086-appb-I000004
， (Bx>0) ，
Figure PCTCN2014070086-appb-I000005
， (Bx<0 ， By>0) ，
Figure PCTCN2014070086-appb-I000006
， (Bx<0 ， By<0) ，
α 和 β 在 (-1800 ， 1800) 之间变化。
隧道磁阻传感器 500 所测量的为检测磁场分量 Bx-y 与其敏感轴的夹角 φ = β - α 。
当角度磁编码器工作时，隧道磁阻传感器 500 保持固定，而永磁体 100 ， 300 围绕轴心旋转，则检测平面内以原点为圆心， r 为半径的圆上各点依次经过隧道磁阻传感器 500 ，并产生旋转磁场，其相位和幅度被隧道磁阻传感器 500 所测量。这等效于永磁体 100 ， 300 保持固定，隧道磁阻传感器 500 依次平移到圆周上不同位置点并测量检测磁场。则此时，永磁体旋转相位角为 α ，而旋转磁场相位角为 φ 。
图 7 为永磁体 100 在检测平面 120 上的三维磁场矢量图，通过对检测平面 120 内二维磁场分量 Bx-y 分布特征进行计算，可以得到 r 在 (0 ， Ro) 范围内变化时旋转磁场相位角 φ 和永磁体旋转相位角 α 的关系，其关系可以是线性关系，非线性关系或介于线性和非线性之间的关系特征。例如，图 8 所示曲线 18 为 旋转磁场相位角 φ 和永磁体旋转相位角 α 之间可能出现的典型的线性关系，图 9 所示曲线 19 为旋转磁场相位角 φ 和永磁体旋转相位角 α 之间可能出现的典型非线性关系，图 10 所示曲线 20 为旋转磁场相位角 φ 和永磁体旋转相位角 α 之间可能出现的介于线性和非线性之间关系特征。图 11 为旋转磁场幅度 Bx-y 和旋转角度 α 关系图，曲线 21 。由曲线 21 看出，旋转磁场幅度是周期 W 形变化，其对应的最大值和最小值为 BH ， BL 。对于磁阻角度传感器而言，希望永磁体在旋转过程中磁场幅度的波动尽可能小，以保证传感器信号不受影响。
采用直线函数来拟合如图 8 ， 9 ， 10 所示的 φ 和 α 之间关系，并计算其线性拟合参数 R2 ， R2 越接近 1 表示线性越好。
曲线 21 所示的磁场波动程度可以采用如下关系式进行表征：
normalized B 数值越小，表明磁场波动越小。
为了确定检测面 120 内旋转磁场相位角 φ 和永磁体旋转相位角 α 之间线性的区域以及非线性的区域的范围，对 r 在（ 0 ， Ro ）之间取不同值时的旋转磁场相位角 φ 和永磁体旋转相位角 α 关系 曲线进行拟合，并计算得到磁场波动关系 normalized B 与永磁体旋转相位角 α 关系曲线。
图 12 为线性拟合参数 R2 与 r/Ro 的关系图。从曲线 22 可以看出，在区域 23 内，其值接近于 1 ，表明在此区域内旋转磁场相位角 φ 和永磁体旋转相位角 α 接近线性关系，因此区域 23 即为隧道磁阻传感器在永磁体 100 的检测面 120 内所对应的特定检测区域，该区域适合于放置隧道磁阻传感器 17 ，而在区域 24 范围内则不适合于隧道磁阻传感器 17 的放置。
图 13 为检测面 120 内， normalized B 与隧道磁阻传感器 500 相对位置 r/Ro 的关系曲线。从曲线 25 可以看出，在特定检测区域 23 内磁场变化幅度适合于隧道磁阻传感器 17 的信号探测。
实施例 4
实施例 4 为根据本发明的另一种角度磁编码器，包括 可绕轴旋转的如具体如实施例 2 所述结构的永磁体，隧道磁阻传感器和数字处理电路。除永磁体外，实施例 4 与实施例 3 相同，这里不再赘述。
图 14 为永磁体 300 在检测面 320 内的三维磁场矢量图，通过对检测平面 310 内二维磁场分量 Bx-y 分布特征进行计算，得到图如 15 ， 16 ， 17 所示的检测面 320 内旋转磁场相位角 φ 和永磁体旋转相位角 α 之间线性关系曲线 26 ，非线性关系曲线 27 和介于线性非线性的关系曲线 28 。线性关系曲线 26 的存在表明永磁体 300 在其检测面上存在旋转磁场相位角 φ 和永磁体旋转相位角 α 之间呈线性关系的区域，该永磁体可以应用于角度磁编码器。
图 18 为旋转磁场幅度 Bx-y 与永磁体旋转相位角度 α 关系图，从曲线 29 可以看出，旋转磁场 Bx-y 随旋转相位角 α 为周期性 M 形波动关系。
同样，为了确定线性区域在检测面 320 内的范围，对不同相对位置 r/Ro 数值的 φ - α 关系曲线进行拟合，得到图 19 所示的线性拟合参数 R2 曲线，由曲线 30 可以看出，检测面 320 内的特定检测区域 31 为适合于隧道磁阻传感器 500 的工作区域，而在区域 32 内则不适合于放置隧道磁阻传感器 500 。进一步，由图 20 可以看出， Normalized B 随隧道磁阻传感器 500 相对位置 r/Ro 关系曲线 33 在特定检测区域 31 内变化幅度相对于非工作区域 32 变化较小。
以上分析可以看出，对于永磁体 100 和永磁体 300 ，在检测平面 120 和 320 内，存在着特定检测区域 23 和 31 ，使得隧道磁阻传感器 500 在该区域内旋转磁场相位角 φ 与永磁体旋转相位角 α 之间存在线性关系，并且其磁场波动幅度满足传感器的要求。这样，隧道磁阻传感器所测量的旋转磁场角度可被转变化成永磁体旋转角度，并由 数字处理电路计算并输出为表征所述永磁体旋转角度的代码， 实现角度磁编码器的角度编码。根据本发明的角度磁编码器可应用于电子水表等领域。
实施例 5
图 21 所示为安装有永磁体 100 或 300 的角度磁编码器的电子水表结构图。下面结合实施例 1 的永磁体和实施例 4 的角度磁编码器描述根据本发明的电子水表。电子水表包括中心转轴和至少一个角度磁编码器。当电子水表包括多个角度磁编码器时， 依次排列的角度磁编码器的转轴间具有确定的转数关系。
例如，永磁体 100 为柱状圆环结构，包含永磁单元 101 和永磁单元 102 ，且相对于直径截面 110 几何对称，永磁单元 101 和永磁单元 102 的对应磁化强度 103 和 104 沿轴线方向反平行，且大小相同。
在每个 角度磁编码器 中，永磁体 100 外径为 3-20 mm ，内径为 1 -15 mm ，轴向长度为 1.5-10 mm ，永磁体 100 镶嵌在数字转轮 2001 中，数字转轮围绕中心轴 2003 转动，隧道磁阻传感器 500 安装在距离永磁体 100 端面 1-5 mm 的检测面 120 内的距离轴心 r/Ro 特定检测区域 23 内，在该特定检测区域内，检测磁场分量的旋转磁场相位角 φ 与永磁体旋转相位角 α 呈线性关系。检测磁场分量 121 为磁场在检测面 120 内的分量。隧道磁阻传感器 500 位于电路板 2002 上，其两端信号通过电路板 2002 输出。数字转轮 2001 安装在中心轴 2003 上，和电路板 2002 一起固定在水表机架 2004 上。由于检测磁场分量 121 的旋转磁场相位角 φ 和永磁体相位角 α 之间的线性关系，因此，能够将根据隧道磁阻传感器 500 测量得到的旋转磁场相位角 φ 和永磁体相位角 α 一一对应起来。隧道磁阻传感器所测量的旋转磁场角度可被转变化成数字转轮的旋转角度，并由 数字处理电路计算并输出为表征所述数字转轮旋转角度的代码。
各磁编码器的各转轴上不同的数字转轮用于读出不同的位数，各转轴相互之间为 10:1 的转数关系。各数字转轮的角位移即为永磁体旋转相位角 α ，可通过各隧道磁阻传感器 500 对与数字转轮相连的永磁体 100 的旋转磁场的测量计算得到。通过将转轮的角度在 0~360 °内分成十个等分，并分别用十个数字进行表征，就可以建立转轮的角位移和数字之间的关系，并通过电路板 2002 上的数字处理电路处理显示成数字代码形式。通过对不同的数字转轮所对应的数字的读取，即可获得电子水表读数直接显示。
安装有永磁体 300 的电子水表的工作原理类似于采用永磁体 100 的电子水表。永磁体 300 为柱状圆环结构，包含永磁单元 301 和永磁单元 302 ，且相对于直径截面 310 几何对称。永磁单元 301 和永磁单元 302 磁化强度大小相同，方向沿垂直于直径截面 310 方向平行。永磁体 300 外径例如为 5-20 mm ，内径为 1-5 mm ，轴向长度为 1-5 mm 。隧道磁阻传感器 500 安装在距离永磁体 300 端面 1-5 mm 的检测面 320 内的距离轴心距离为 r/Ro 的特定检测区域 31 内，在该特定检测区域内，检测磁场分量的旋转磁场相位角 φ 与永磁体旋转相位角 α 呈线性关系。检测磁场分量 321 为磁场在检测面 320 内的分量。其检测过程类似于采用永磁体 100 的电子水表，这里不再赘述。
以上所述仅为本发明的优选实施例而已，并不用于限制本发明，对于本领域的技术人员来说，本发明可以有各种更改和变化。凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。

Claims (14)

1 ．一种适用于角度磁编码器的永磁体， 该永磁体 (100 ， 300) 具有柱状圆环结构，并包含第一永磁单元 (101 ， 301) 和第二永磁单元 (102 ， 302) ，所述第一永磁单元 (101 ， 301) 和第二永磁单元 (102 ， 302) 相对于直径截面 (110 ， 310) 几何对称， 其特征在于，
所述第一永磁单元 (101 ， 301) 的 磁化强度 (103 ， 303) 和第二永磁单元 (102 ， 302) 的磁化强度 (104 ， 304) 平行于柱状圆环的轴向，且方向相反，或
所述第一永磁单元 (101 ， 301) 的 磁化强度 (103 ， 303) 和第二永磁单元 (102 ， 302) 的磁化强度 (104 ， 304) 垂直于所述直径截面 (110 ， 310) ，且方向平行一致。
2 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于，所述第一永磁单元 (101 ， 301) 的 磁化强度 (103 ， 303) 和第二永磁单元 (102 ， 302) 的磁化强度 (104 ， 304) 大小相同。
3 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于，所述永磁体 (100 ， 300) 柱状圆环结构的外径为 3-200mm 。
4 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于，所述永磁体 (100 ， 300) 柱状圆环结构的内径为 1-100 mm 。
5 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于，所述永磁体 (100 ， 300) 柱状圆环结构的轴向长度为 1-50 mm 。
6 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于，所述永磁体 (100 ， 300) 所对应的检测面 (120 ， 320) 位于柱状圆环端面前方且平行于底面。
7 ．根据权利要求 6 所述的一种适用于角度磁编码器的永磁体，其特征在于，所述检测面 (120 ， 320) 与所述柱状圆环端面之间的距离为 1-5 mm 。
8 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于，永磁体 (100 ， 300) 所对应的检测磁场分量为磁场在检测面 (120 ， 320) 内的分量。
9 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于， 特定检测区域 (23 ， 31) 位于检测面 ( 120 ， 320 ) 内距离柱状圆环轴心特定半径范围的区域内，在该特定检测区域内检测磁场分量的旋转相位角（ φ ）和永磁体的旋转相位角（ α ）具有线性变化特征 。
10 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于，所述永磁体 (100 ， 300) 的组成材料为 Alnico 。
11 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于，永磁体 (100 ， 300) 的组成材料为铁氧体陶瓷材料 MO·6Fe2O3 ， M 为 Ba ， Sr 或者两者的组合。
12 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于，永磁体 (100 ， 300) 的组成材料为选自 RECo5 ，其中 RE=Sm 和 / 或 Pr ； RE2TM17 ，其中 RE=Sm ， TM=Fe ， Cu ， Co ， Zr 和 / 或 Hf ；以及 RE2TM14B ，其中 RE=Nd ， Pr 和 / 或 Dy ， TM=Fe 和 / 或 Co 中的一种或多种。
13 ．根据权利要求 1 所述的一种适用于角度磁编码器的永磁体，其特征在于，永磁体 (100 ， 300) 的组成材料为选自 FeCrCo 合金和 NbFeB 合金中的一种或多种。
14 ．根据权利要求 10-13 中任一权利要求的一种适用于角度磁编码器的永磁体，其特征在于，永磁体 (100 ， 300) 为所述永磁体 (100,300) 的组成材料的粉末和塑料、橡胶或树脂形成的复合体。
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9715959B2 (en) 2013-01-05 2017-07-25 MultiDimension Technology Co., Ltd. Permanent magnet suitable for magnetic angle encoder
EP3255391A4 (en) * 2015-02-04 2018-11-21 Multidimension Technology Co., Ltd. Magnetic automation flow recorder

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103913183A (zh) * 2013-01-09 2014-07-09 江苏多维科技有限公司 一种角度磁编码器和电子水表
DE102015210586A1 (de) * 2015-06-10 2016-12-15 Schaeffler Technologies AG & Co. KG Verfahren zum Betrieb eines Umdrehungssensors und entsprechender Umdrehungssensor
US10591274B2 (en) * 2016-09-28 2020-03-17 Infineon Technologies Ag External field robust angle sensing with differential magnetic field
US11550362B2 (en) * 2021-03-31 2023-01-10 Microsoft Technology Licensing, Llc Rotatably coupled touch screen displays
CN114659543B (zh) * 2022-05-20 2022-07-29 唐山工业职业技术学院 一种高精度多对极磁电编码器

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03283407A (ja) * 1990-03-29 1991-12-13 Matsushita Electric Ind Co Ltd 複合磁石及びその製造方法
CN1271416A (zh) * 1997-09-08 2000-10-25 株式会社安川电机 磁编码装置
JP2000308326A (ja) * 1999-04-15 2000-11-02 Japan Science & Technology Corp 発電装置およびそれを使用した生体用電子機器
CN203300354U (zh) * 2013-01-05 2013-11-20 江苏多维科技有限公司 一种适用于角度磁编码器的永磁体

Family Cites Families (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0328407A (ja) 1989-06-24 1991-02-06 Shigeto Kumagai 地表水の高速水はけ構造
JPH05198425A (ja) * 1992-01-22 1993-08-06 Mazda Motor Corp 回転センサの磁石体およびその製造方法
US6084401A (en) * 1998-04-02 2000-07-04 Ford Globa Technologies, Inc. Rotational position sensor employing magneto resistors
US6310473B1 (en) * 1998-12-15 2001-10-30 Kearney-National, Inc. Magnetic rotational position sensor
JP2001304805A (ja) * 2000-04-25 2001-10-31 Tokai Rika Co Ltd 回転角度検出装置
JP2002022406A (ja) * 2000-07-11 2002-01-23 Yazaki Corp 回転角センサ
DE10339126B4 (de) * 2003-08-22 2009-04-02 Zf Friedrichshafen Ag Kugelgelenk mit Winkelsensor
WO2006067878A1 (ja) * 2004-12-20 2006-06-29 Harmonic Drive Systems Inc. リング状マグネットの着磁方法および磁気エンコーダ
JP4947535B2 (ja) * 2005-02-01 2012-06-06 内山工業株式会社 磁気エンコーダ用ゴム組成物およびそれを用いた磁気エンコーダ
JP4729358B2 (ja) * 2005-08-03 2011-07-20 旭化成エレクトロニクス株式会社 回転角度センサ
EP2004446B1 (en) * 2006-03-13 2014-01-01 Magswitch Technology Worldwide Pty Ltd Magnetic wheel
DE102006018627A1 (de) * 2006-04-21 2007-10-25 Siemens Ag Magnetischer Drehwinkelgeber
JP5021253B2 (ja) * 2006-08-24 2012-09-05 株式会社デンソー 回転角度検出装置
DE102007013755B4 (de) * 2007-03-22 2020-10-29 Te Connectivity Germany Gmbh Indikatorelement für einen magnetischen Drehwinkelgeber
EP2056307B1 (de) * 2007-10-01 2010-12-22 Albert Maurer Lösevorrichtung zum Lösen von magnetisch lösbaren Diebstahlsicherungen
JP5202343B2 (ja) * 2009-01-08 2013-06-05 三菱電機株式会社 回転角検出器
JP5231365B2 (ja) * 2009-09-08 2013-07-10 Ｎｔｎ株式会社 回転角度検出センサ
JP6001450B2 (ja) * 2009-09-22 2016-10-05 コルレイティド マグネティクス リサーチ，リミティド ライアビリティ カンパニー 多重レベル相関磁気システム及びその使用法
FR2965347B1 (fr) * 2010-09-29 2015-04-03 Moving Magnet Tech Capteur de position ameliore
CN202974369U (zh) * 2012-08-24 2013-06-05 江苏多维科技有限公司 直读式计量装置和直读式水表
CN103915233B (zh) 2013-01-05 2017-02-08 江苏多维科技有限公司 一种适用于角度磁编码器的永磁体

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03283407A (ja) * 1990-03-29 1991-12-13 Matsushita Electric Ind Co Ltd 複合磁石及びその製造方法
CN1271416A (zh) * 1997-09-08 2000-10-25 株式会社安川电机 磁编码装置
JP2000308326A (ja) * 1999-04-15 2000-11-02 Japan Science & Technology Corp 発電装置およびそれを使用した生体用電子機器
CN203300354U (zh) * 2013-01-05 2013-11-20 江苏多维科技有限公司 一种适用于角度磁编码器的永磁体

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9715959B2 (en) 2013-01-05 2017-07-25 MultiDimension Technology Co., Ltd. Permanent magnet suitable for magnetic angle encoder
EP3255391A4 (en) * 2015-02-04 2018-11-21 Multidimension Technology Co., Ltd. Magnetic automation flow recorder

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US20150332831A1 (en) 2015-11-19
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EP2942794A4 (en) 2016-09-14

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