CN106052725B - A kind of Z-X axis magnetic resistance sensor - Google Patents

Abstract

The present invention proposes a Z-X axis magnetoresistive sensor to measure parameters of gears or multi-magnetic poles. The magnetoresistance sensor is a single-chip Z-X axis magnetoresistance sensor, comprising: The elongated soft magnetic flux concentrator on the bottom, and the magnetoresistive sensing unit string with the magnetic sensitivity direction along the X direction on the upper or lower surface of the soft magnetic flux concentrator, including the Y-axis centerline of the soft magnetic flux concentrator, the Y Reference, push, and pull magnetoresistive sensing unit strings on both sides of the shaft center line and equidistant, and two sensitive magnetoresistive sensing unit strings in the soft magnetic flux gap, and the push, pull magnetoresistive sensing unit strings and reference, sensitive The magnetoresistive sensing unit strings are staggered and connected into a reference bridge type X-axis sensor and a push-pull bridge type Z-axis sensor; the invention has the advantages of simple sensor structure, high sensitivity, low power consumption, small size, and the ability to measure any period interval Advantages of gears and multiple poles.

Description

A Z-X axis magnetoresistance sensor

technical field

The invention relates to the field of magnetic sensors, in particular to a Z-X axis magnetoresistance sensor.

Background technique

Magnetoresistive gears or multi-pole sensors are widely used to measure speed and displacement. The gears include flat strip gears or circular gears. The periodic change of the magnetic field generated on the surface of the magnetoresistive sensor when the tooth root and the tooth top pass through the back magnetic field in turn forms a sinusoidal output signal; while the multi-pole sensor is an incremental encoder, which adopts a planar strip shape or a circle NS-shaped alternating free magnetic poles, the free magnetic poles generate a magnetic field on the magnetoresistive sensor to form a sinusoidal output signal. Usually, when the magnetoresistive sensor outputs two sinusoidal signals with a phase difference of 90 degrees, the output voltage signal has the maximum value. And can determine the position of the sensor relative to the gear or multi-pole and the speed of the latter's movement.

Usually, the magnetoresistive sensor is a gradient type, including two sets of X or Z axis magnetoresistive sensor units separated by a characteristic distance, and when the characteristic distance is 1/4 of the periodic distance of the gear or multi-pole, the phase difference between the two is 90 , the output signal is the strongest at this time.

However, when the period length of gears or multi-poles is large, the two sets of magnetoresistive sensing units in the magnetoresistive sensor are also required to be separated by a large characteristic distance, which poses a challenge to the size and packaging of the magnetoresistive sensor. .

The recent patent CN104197828A discloses a single-chip off-axis magnetoresistive Z-X angle sensor and measuring instrument, including a bipolar magnetic encoder code disc whose magnetization direction is along the circular radial direction, and a single-chip Z-X angle sensor, the Z-X The angle sensor is located in the tangential direction of the circular code disc, including an X-axis magnetoresistive sensor along the substrate, and a Z-axis magnetoresistive sensor perpendicular to the substrate. During the test, the Z-axis direction is along the diameter of the magnetic encoder code disc direction, and the X-axis direction is along the tangential direction of the magnetic encoder code disc, thus realizing the output of two sinusoidal signals with a difference of 90 degrees. It is characterized in that the X-axis and Z-axis magnetoresistive sensors are located in the same chip, and It can be a single chip, and there is no separation feature distance requirement.

Aiming at the problem of measuring the position and speed of gears or multi-magnetic poles, the present invention proposes a new solution, that is, using X-Z magnetoresistive sensors, using the X-axis and Z-axis components of the magnetic circuit as magnetic signals to realize gear or multi-magnetic pole positions. and speed measurement.

Contents of the invention

Aiming at the problem of measuring the position and speed of gears or multi-magnetic poles, the present invention proposes a new solution, that is, adopting Z-X magnetoresistive sensors, using the X-axis and Z-axis components of the magnetic circuit as magnetic signals to realize gear or multi-magnetic pole positions and speed measurement.

A Z-X axis magnetoresistance sensor proposed by the present invention is used to detect the position, direction of motion, speed and acceleration of a device under test such as gears or multi-poles. The Z-X axis magnetoresistance sensor is located parallel to the tangent plane of the device under test And on the working plane with a predetermined gap from the tangent plane, the X-axis magnetic field sensitive direction of the Z-X axis magnetoresistive sensor is parallel to the tangent plane and along the tangential movement direction of the device under test, and the Z-X axis magnetic field The Z-axis magnetic field sensitive direction of the resistance sensor is perpendicular to the tangent plane, the device under test is a gear or a multi-pole, and the Z-X-axis magnetoresistance sensor is a single-chip Z-X-axis magnetoresistance sensor, including:

A substrate located on the X-Y plane, a plurality of elongated soft magnetic flux concentrators arranged in parallel along the Y and X directions with the long axis and short axis respectively located on the substrate, and the upper surface of the soft magnetic flux concentrator or A plurality of magnetoresistive sensing unit strings with a magnetic field sensitive direction along the X axis arranged in parallel along the Y direction on the lower surface;

The magnetoresistance sensing unit string includes: a reference magnetoresistance sensing unit string located on the Y-axis centerline of the flux concentrator, a sensitive magnetoresistor located at a gap between the Y-axis centerline of the flux concentrator a string of sensing units, and a string of pushing magnetoresistive sensing units and a string of pulling magnetoresistive sensing units respectively located on both sides of the centerline of the Y-axis of the flux concentrator and equidistant from the centerline of the Y-axis, and the The push magnetoresistance sensing units are electrically connected in series to form a push arm, the pull magnetoresistance sensing units are electrically connected in series to form a pull arm, the reference magnetoresistance sensing units are electrically connected in series to form a reference arm, and the sensitive magnetoresistance sensing units are electrically connected in series to form a reference arm. The unit strings are electrically connected to form a sensitive arm, and the push arm, the pull arm, the reference arm, and the sensitive arm are further connected to form a reference bridge type X-axis sensor and a push-pull bridge type Z-axis sensor, which are used to detect the X-axis and Z-axis magnetic fields respectively. Component: the magnetoresistance sensing unit strings of the reference bridge X-axis sensor and the magnetoresistance sensing unit strings of the push-pull bridge Z-axis sensor are arranged alternately.

Preferably, the magnetoresistance sensing unit forming the magnetoresistance sensing unit string is a GMR or TMR magnetoresistance sensing unit, which sequentially includes a seed layer, a lower electrode layer, a pinned layer, a pinning layer, An isolation layer, a free layer, a bias layer, an upper electrode layer and a cover layer, the material of the isolation layer is Al2O3, MgO or metal, and the bias layer is an exchange bias layer or a permanent magnetic bias layer.

preferred,

The pinned layer is located on a side of the pinned layer away from the isolation layer;

The exchange bias layer is located on the side of the free layer away from the isolation layer;

The ferromagnetic material of at least one layer of the free layer, the pinned layer, the pinned layer, and the bias layer is composed of a high magnetic permeability material containing at least one of Fe, Co, and Ni. Made of soft magnetic material.

Preferably, the magnetization direction of the pinned layer is the X-axis direction, and the magnetization direction of the free layer is the Y-axis direction.

Preferably, the soft magnetic flux concentrators corresponding to the reference magnetoresistance sensing unit strings, the pushing magnetoresistance sensing unit strings, and the pulling magnetoresistance sensing unit strings are occupying soft magnetic flux concentrators, and the rest of the soft magnetic flux concentrators are The device is an empty soft magnetic flux concentrator, and the reference magnetoresistance sensing unit string, the pushing magnetoresistance sensing unit string, and the pulling magnetoresistance sensing unit string are located on the same occupied soft magnetic flux concentrator or are respectively located in three The occupied soft magnetic flux concentrators or two occupied soft magnetic flux concentrators respectively; between concentrators or between one of said vacant soft magnetic flux concentrators and one of said occupied soft magnetic flux concentrators.

Preferably, the push-pull magnetoresistance sensing unit string and the pull magnetoresistance sensing unit string occupy N push-pull magnetoresistance sensing unit regions R1, R2,..., RN, and the reference magnetoresistance sensing unit string And the sensitive magnetoresistance sensing unit string occupies M reference sensitive magnetoresistance sensing unit areas P1, P2,..., PM, and the staggered arrangement is any one of the following, two or three combinations: N is Integer and N≥1, M is an integer and M≥1;

1) When N=M, (R1,P1),...(Ri,Pi)...,(RN,PM) or (P1,R1),...(Pi,Ri)...,(PM,RN);

2) N=2i, M=2i-1, when;

R1,(P1,R2),...(Pi-1,Ri),(Pi),(Ri+1,Pi+1),...(R2i-1,P2i-1),R2i;

Or N=2i-1, M=2i, when;

P1,(R1,P2),...(Ri-1,Pi),(Ri),(Pi+1,Ri+1),...(P2i-1,R2i-1),P2i

3) N=2j-1, M=2j-2,

(R1,P1),...(Rj-1,Pj-1),Rj,(Pj,Rj+1),...,(P2j-2,R2j-1)

Or M=2j-1, N=2j-2,

(P1,R1),...(Pj-1,Rj-1),Pi,(Rj,Pj+1),...,(R2j-2,P2j-1);

The i is an integer and i≥1, and j is an integer and j≥2.

Preferably, the push-pull magnetoresistance sensing unit area includes one or more push magnetoresistance sensing unit strings and one or more pull magnetoresistance sensing unit strings, and the reference sensitive magnetoresistance sensing unit area includes One or more strings of sensitive magnetoresistance sensing units, and one or more strings of sensitive magnetoresistance sensing units.

Preferably, the gaps between the soft magnetic flux concentrators in the region of the push-pull magnetoresistive sensing unit are the same, and the gaps between the soft magnetic flux concentrators in the region of the reference sensitive magnetoresistive sensing unit are the same.

preferred,

The magnetic poles included in the multi-pole have magnetization parallel to the tangential direction, and two adjacent magnetic poles have antiparallel magnetization or clockwise and counterclockwise opposite magnetization respectively,

Or the included magnetic poles have magnetization perpendicular to the direction of the tangent plane, and the two adjacent magnetic poles respectively have antiparallel magnetization or have centripetal and centrifugal opposite magnetizations respectively.

Preferably, the device under test further includes a back magnet for providing a magnetic field to magnetize the gear; wherein,

The back magnet is a cuboid permanent magnet alloy material, its width and height directions are respectively along the X-axis and Z-axis magnetic field sensitive directions, and its magnetization direction is along the Z-axis magnetic field sensitive direction;

or,

The back magnet is a cylindrical permanent magnet alloy material, and its magnetization direction and axial direction are both along the Z-axis magnetic field sensitive direction;

or,

The back magnet is a square permanent magnet alloy material with a concave groove on the surface, the bottom surface of the concave groove is perpendicular to the Z-axis sensitive direction, and the magnetization direction is along the Z-axis magnetic field sensitive direction.

Preferably, the Z-X axis magnetoresistive sensor is located between the back magnet and the gear, and on the surface of the back magnet.

preferred,

When the gear is tested, the back magnetic width is greater than 0.5 times of the gear period interval;

or,

When the gear is tested, the specific gap between the Z-X axis magnetoresistive sensor and the gear is greater than 0.1 times and less than 1.0 times the gear cycle pitch.

The invention has the advantages of simple sensor structure, high sensitivity, low power consumption, small size, and the ability to measure any periodic pitch gear and multi-magnetic poles.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments described in this application. Those skilled in the art can also obtain other drawings based on these drawings without any creative effort.

Fig. 1 is the test diagram of elongated gear and sensor;

Figure 2 is a vertically magnetized elongated multi-pole and sensor test diagram;

Fig. 3 is a strip-shaped multi-pole and sensor test diagram of parallel magnetization;

Fig. 4 is a wheel-shaped multi-pole and sensor test diagram of radial magnetization;

Fig. 5 is a wheel-shaped multi-pole and sensor test diagram of normal magnetization;

Fig. 6 is a wheel gear and a sensor test diagram;

Fig. 7 is a structural diagram of a traditional X-direction gear or multi-pole sensor;

Fig. 8 is a structural diagram of a traditional Z-direction gear or a multi-pole sensor;

Fig. 9 is a traditional X-direction or Z-direction gear or multi-pole sensor signal output diagram;

Figure 10 is a structural diagram of a single-chip Z-X gear or a multi-pole sensor;

Figure 11 is a Z-X gear or multi-pole sensor signal output diagram;

Fig. 12 is a structural diagram of a single-chip Z-X magnetoelectric group sensor;

Figure 13a is a structural diagram of the magnetoelectric group sensing unit;

Figure 13b is a schematic diagram of the magnetization direction of the magnetoelectric group sensing unit;

Figure 14a is a structure diagram of the X-axis magnetoresistive sensor as a reference bridge;

Figure 14b is a push-pull bridge structure diagram of the Z-axis magnetoresistive sensor

Fig. 15a is a position relationship diagram of reference magnetoresistive sensing unit strings;

Fig. 15b is a position relational diagram of push or pull magnetoresistive sensing unit strings;

Fig. 15c is a position relation diagram of pull or push magneto-resistive sensing unit strings;

Fig. 16a is a position relation diagram of reference, push and pull magnetoresistive sensing unit strings corresponding to a soft magnetic flux concentrator;

Fig. 16b is a position relationship diagram of the reference, push and pull magnetoresistive sensing unit strings corresponding to the three magnetoresistive sensing unit strings;

Fig. 16c is a position relationship diagram of reference, push and pull magnetoresistive sensing unit strings corresponding to two magnetoresistive sensing unit strings;

Fig. 17a is a position relationship diagram of sensitive magnetoresistive sensing unit strings corresponding to two vacant soft magnetic flux concentrators;

Fig. 17b is a position relationship diagram of sensitive magnetoresistive sensing unit strings corresponding to an empty soft magnetic flux concentrator and an occupied soft magnetic flux concentrator;

Figure 17c is a schematic diagram of a string of sensitive magnetoresistive sensing units located between two occupied soft magnetic flux concentrators;

Figure 18a is a schematic diagram of an empty soft magnetic flux concentrator;

Figure 18b is a schematic diagram of an occupied soft magnetic flux concentrator;

Figure 19a is a schematic diagram of the arrangement of 4000;

Figure 19b is a schematic diagram of the arrangement of 4001;

Figure 20a is a schematic diagram of the arrangement of 4002;

Figure 20b is a schematic diagram of the arrangement of 4003;

Figure 21a is a schematic diagram of the arrangement of 4004;

Figure 21b is a schematic diagram of the arrangement of 4005;

Fig. 22 is a schematic diagram of arrangement mode 1 of magnetoresistive sensing unit strings on the Z-X magnetoresistive sensor;

Fig. 23 is a schematic diagram of the second arrangement mode of the magnetoresistance sensing unit string on the Z-X magnetoresistance sensor;

Fig. 24 is a schematic diagram of the third arrangement of magnetoresistive sensing unit strings on the Z-X magnetoresistive sensor;

Fig. 25 is a schematic diagram of four arrangements of magnetoresistive sensing unit strings on the Z-X magnetoresistive sensor;

Fig. 26 is a schematic diagram of five arrangement modes of magnetoresistance sensing unit strings on the Z-X magnetoresistance sensor;

Fig. 27 is a schematic diagram of a block-shaped back magnetic structure;

Fig. 28 is a schematic diagram of a cylindrical back magnetic structure;

Fig. 29 is a schematic diagram of a slotted block-shaped back magnetic structure.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

Embodiment one

Figure 1-6 is a schematic diagram of the measurement of several common gears, multi-pole and magnetoresistance sensors. Fig. 1 is the measuring schematic diagram of elongated gear and magnetoresistive sensor, wherein 10 is an elongated gear, including tooth head 20 and tooth head gap 21, the distance between the two is the period interval of elongated gear, and 40 is the gear The sensor is located on the plane 81 parallel to the tooth top of the elongated gear, and has a certain gap from the tooth top, and also includes the back magnet 3 on the surface of the gear sensor, wherein the gear sensor 40 is located between the back magnet 3 and the elongated gear 10 Among them, the elongated gear 10 is a soft magnetic alloy material, and the back magnet 3 is a hard magnetic alloy material.

Fig. 2 and Fig. 3 are two forms of elongated multi-magnetic poles and magnetoresistive sensor measurement schematic diagrams, wherein the elongated multi-magnetic poles 11 in Fig. 2 and the elongated multi-magnetic poles 12 in Fig. 3 all comprise a plurality of free magnetic poles, And two adjacent free magnetic poles have opposite magnetization directions, wherein the adjacent free magnetic poles 30 and 31 in FIG. 2 are respectively the magnetization directions in the Z direction, and the adjacent free magnetic poles 40 and 41 in FIG. Magnetization direction, the free magnetic poles are all permanent magnet alloy materials, the multi-pole sensors 41 and 42 are respectively located on the planes 82 and 83 parallel to the surfaces of the strip-shaped multi-poles 11 and 12, and there is a specific gap from the strip-shaped multi-pole surfaces , the elongated multipoles have a specific periodic spacing.

Fig. 4 and Fig. 5 are respectively the two forms of wheel-shaped multi-magnetic poles and magnetoresistive sensor measurement diagrams, wherein the wheel-shaped free magnetic pole 13 in Fig. 4 and the wheel-shaped free magnetic pole 14 in Fig. 5 all include a plurality of arc-shaped free magnetic poles , and two adjacent free magnetic poles have opposite magnetization directions in polar coordinates, that is, the adjacent free magnetic poles 50 and 51 in Figure 4 are centripetal and centrifugal directions respectively, while the adjacent free magnetic poles 60 and 61 are positive theta and reverse theta angle directions respectively, and its period interval is the circular arc corresponding to Theta, wherein the multi-magnetic pole sensors 43 and 44 are respectively located on the planes 84 and 85 parallel to the tangent planes of the wheel-shaped multi-magnetic poles 13 and 14, and A specific gap from the cut plane.

Fig. 6 is a measurement schematic diagram of a wheel-shaped gear and a magneto-resistive sensor, wherein 70 cycles of tooth heads are circularly distributed, and the gap between adjacent tooth heads is 71. Similarly, the period interval is the arc corresponding to Theta, and the gear 15 is soft magnetic Alloy alloy material, the magnetic wheel sensor 45 is located on a plane 86 parallel to the tangential plane of the magnetic wheel, and has a certain gap from the tangential plane of the gear, and also includes a back magnet 7, which is located on the surface of the gear sensor 45, and the back magnet 7 is a permanent magnet alloy Material.

Embodiment two

7 and 8 are structural diagrams of conventional gear or multi-pole sensors 100 and 101, respectively, wherein the gear or multi-pole sensors 100 and 101 respectively include two sensing units 200, 201 and 300 separated by a characteristic pitch 1 and a characteristic pitch and 301, wherein the two magnetoresistance sensing units 200 and 201 in Fig. 7 have X-axis magnetic field sensitive directions Hx1 and Hx2, and the two magnetoresistance sensing units 300 and 301 in Fig. 8 have Z-axis magnetic field sensitive directions Hz1 and Hz2, the above is the coordinate representation method under the strip-shaped magnetic pole or gear. For the wheel-shaped gear or magnetic pole, in polar coordinates, the direction corresponding to the X-axis is the Theta angle, and the direction corresponding to the Z-axis is the r direction.

Figure 9 is a signal output diagram corresponding to the traditional gear or multi-pole sensor shown in Figure 7 and Figure 8, when the output signals V1 and V2 are two sine or cosine signals with a phase difference of 90 degrees, the output position signal is the strongest, At this time, the following relationship must be satisfied between the characteristic spacing of traditional gears or multi-pole sensors 100 and 101 and the periodic spacing of multi-magnetic poles or gears, that is, the characteristic spacing is 1/4 of the periodic spacing, so for multi-magnetic poles with large periodic spacing Or gears, correspondingly require two magneto-resistive sensing units to increase the installation distance, resulting in an excessively large chip size.

Embodiment Three

FIG. 10 is a structural diagram of a single-chip Z-X magnetoresistance sensor proposed in the present application, wherein the single-chip Z-X magnetoresistance sensor 102 includes a single magnetoresistance sensing unit 400, capable of responding to the X-axis magnetic field and the Y-axis magnetic field. Including the X-axis magnetoresistance sensor and the Z-axis magnetoresistance sensor, the X-axis and Z-axis magnetoresistance sensors have the same magnetic field sensitive area and are interlaced with each other.

Figure 11 shows the X-axis magnetic field component and the Z-axis magnetic field component at the sensor position when the gear or multi-magnetic pole sensor of different types shown in Figure 1-6 is working. From the distribution diagram, it can be seen that both the X-axis magnetic field component Bx and the Z-axis magnetic field component Bz have sine and cosine characteristics, and the phase difference is 90 degrees, which has the same effect as the traditional gear or multi-pole sensor. It must be emphasized that for For the multi-pole sensors shown in Figure 2-5, the sensor can meet the working conditions on any gap on the multi-pole surface, but for the gear sensor shown in Figures 1 and 6, it must meet a certain range of working gaps. In addition, its back magnetism is also It must meet a certain width, and the width along the direction of the periodic gap. The range of the working gap is that the back magnetic width is greater than 0.5 times the gear cycle pitch, and the working gap is greater than 0.1 and less than 1.0 times the gear cycle pitch.

The advantage is that the single-chip Z-X magnetoresistance sensor does not need to separate the characteristic pitch, but measures the X magnetic field and Z magnetic field components in the same area, so the size of the Z-X magnetoresistance sensor is smaller.

Embodiment Four

Figure 12 is a single-chip Z-X magnetoresistive sensor 900 proposed by the present application, including a substrate 901 on the X-Y plane, a magnetoresistive sensing unit layer 902 on the substrate, and a soft magnetic flux concentrator layer 903, and The magnetoresistance sensing unit layer 902 is located on the upper surface or the lower surface of the soft magnetic flux concentrator layer 903. FIG. 13 is a structural diagram of the magnetoresistance sensing unit. The magnetoelectric group sensing unit 800 in FIG. 802, a pinning layer 803, a pinned layer 804, an isolation layer 805, a free layer 806, a bias layer 807, an upper electrode layer 808 and a covering protection layer 809, wherein the isolation layer 805 can be Al2O3, MgO or a metal layer Cu, The free layer 806 or the pinned layer 804 is a high permeability soft magnetic alloy material containing Fe, Co, Ni, and the pinned layer is an antiferromagnetic material IrMn or PtMn, or contains a ferromagnetic material layer/metal interlayer/ Ferromagnetic material layer, the bias layer is a permanent magnetic alloy material layer or an exchange bias layer such as an antiferromagnetic material layer such as PtMn or IrMn, or contains a ferromagnetic material/metal interlayer/ferromagnetic material layer, and Figure 13b is a magnetic The magnetization direction of the electric group sensing unit, wherein the magnetization direction of the free layer is along the long axis direction, and the magnetization direction of the pinned layer is along the short axis direction, and the angle between them is 90 degrees.

Figure 14 is a bridge structure diagram of the X-axis magnetoresistance sensor and the Z-axis magnetoresistance sensor, wherein 14a shows that the X-axis magnetoresistance sensor is a reference bridge structure, including a reference magnetoelectric group sensing unit and a sensitive magnetoelectric group sensor Sensing unit, Fig. 14b shows that the Z-axis magnetoresistive sensor is a push-pull bridge structure, including a push magnetoelectric group sensing unit and a pull magnetoelectric group sensing unit.

Fig. 15 is a schematic diagram of three kinds of magnetoresistance sensing unit strings, characterized in that the magnetoresistance sensing unit strings are located on the elongated soft magnetic flux concentrator, wherein 15a is a reference magnetoelectric group sensing unit string 3000, wherein the magnetoresistance The sensing unit string 3003 is located on the Y-axis centerline 3002 of the elongated soft magnetic flux concentrator 3001. Figures 15b and 15c are respectively push or pull magnetoelectric group sensing unit strings 3004, 3008, wherein the magnetoelectric group sensing unit strings 3006 and 3011 are located on both sides of the centerlines 3005 and 3010 of the elongated soft magnetic flux concentrators 3007 and 3009 respectively, and are at the same distance from the centerlines.

Fig. 16 is an arrangement structure diagram of the reference, push and pull magnetoresistive sensing unit strings shown in Fig. 15, wherein in 3013 of Fig. 16a, three kinds of magnetoresistance sensing unit series push and pull magnetoelectric group sensing unit strings 3015 and 3013 and the reference magnetoresistive sensing unit string 3017 are respectively located on a strip-shaped soft magnetic flux concentrator, and in 3018 of FIG. The magnetoresistance sensing unit string 3023 and the reference magnetoresistance sensing unit string 3024 are respectively located on three elongated soft magnetic flux concentrators. In 3025, 3032 and 3038 of FIG. 16c, the three magnetoresistance sensing unit strings are located on two On the elongated soft magnetic flux concentrator, the 16c1 push-pull magnetoresistance sensing unit strings 3029 and 3027 occupy one of the elongated soft magnetic flux concentrators 3027, while the reference magnetoresistance sensing unit string 3028 occupies the other elongated The soft magnetic flux concentrators 3026, 16c2's push magnetic electric group sensing unit string 3035 and reference magnetic resistance sensing unit string 3034 occupy one of the soft magnetic flux concentrators 3034, and the pull magnetic resistance sensing unit string 3037 occupies the other soft magnetic flux concentrator. In the devices 3033 and 16c3, the pulling magnetoresistance sensing unit string 3043 and the reference magnetoresistance sensing unit string 3042 occupy one of the soft magnetic flux concentrators 3039, and the pushing magnetoelectric group sensing unit string 3041 occupies the other soft magnetic flux concentrator 3040.

Figure 17 is a location diagram of sensitive magnetoresistance sensing units, 3044 in 17a is a sensitive magnetoresistance sensing unit string 3047 located between two vacant soft magnetic flux concentrators 3045 and 3046, 3048 in 17b is a sensitive magnetoresistance sensing unit string 3051 is located between a vacant soft magnetic flux concentrator 3049 and an occupied soft magnetic flux concentrator 3059, and 3052 in 17c is a string of sensitive magnetoresistive sensing units 3055 located between two occupied soft magnetic flux concentrators 3052 and 3053.

Figure 18 is a type diagram of a strip-shaped soft magnetic flux concentrator, in which 3056 in 18a is an empty soft magnetic flux concentrator without any magnetic resistance sensing unit strings, and 18b is an occupied soft magnetic flux concentrator with a magnetic resistance sensor The function of the unit string, the vacant type soft magnetic flux concentrator is to make the position of the magnetoresistance sensing unit string have a uniform magnetic field, or to make the magnetoresistance sensing unit string meet the characteristics of spatially symmetrical distribution.

Embodiment five

Figure 19-21 is a typical array of magnetoresistive sensing units of a single-chip Z-X magnetoresistive sensor. In order to ensure that the X-axis magnetoresistive sensor and the Z-axis magnetoresistive sensor have the same magnetic field induction range, the X-axis magnetoresistive sensor is required The reference and sensitive magnetoresistive sensing unit strings corresponding to the unit strings and the push and pull magnetoresistive sensing unit strings corresponding to the Z-axis magnetoresistance sensing unit strings are arranged alternately, assuming that the push magnetoresistance sensing unit strings and the pulling magnetoresistance The sensing unit string occupies N (N is an integer greater than or equal to 1) push-pull magnetoresistive sensing unit regions R1, R2, ..., RN, and the reference magnetoresistive sensing unit string and the sensitive magnetoresistive sensing unit string occupy M ( M is an integer greater than or equal to 1) reference sensitive magnetoresistive sensing unit areas P1, P2, ..., PM, then the staggered arrangement is any one of the following, two or three combinations:

1) When N=M, (R1,P1),...(Ri,Pi)...,(RN,PM) or (P1,R1),...(Pi,Ri)...,(PM,RN);

2) When N=2i, M=2i-1, (i is an integer greater than or equal to 1);

R1,(P1,R2),...(Pi-1,Ri),(Pi),(Ri+1,Pi+1),...(R2i-1,P2i-1),R2i;

Or when N=2i-1, M=2i, (i is an integer greater than or equal to 1);

P1,(R1,P2),...(Ri-1,Pi),(Ri),(Pi+1,Ri+1),...(P2i-1,R2i-1),P2i

3) When N=2i-1, M=2i-2, (i is an integer greater than or equal to 2);

(R1,P1),...(Ri-1,Pi-1),Ri,(Pi,Ri+1),...,(P2i-2,R2i-1)

Or M=2i-1, N=2i-2, (i is an integer greater than or equal to 2)

(P1,R1),...(Pi-1,Ri-1),Pi,(Ri,Pi+1),...,(R2i-2,P2i-1)

4000 in Figure 19a and 4001 in Figure 19b respectively correspond to the first arrangement, 4000 is arranged as Z1/X1/Z2/X2/Z3/X3, and 4001 is arranged as X1/Z1/X2/Z2/X3/Z3.

Figure 20 corresponds to the second arrangement, where 4002 in 20a is arranged as X1/Z1/X2/Z2/Z3/X3/Z4/X4, where Z2 and Z3 form a common area, and 4003 in 20b are arranged Z1/X1/Z2/X2/X3/Z3/X4/Z4, where X2 and X3 form a common area.

Figure 21 corresponds to the third arrangement, where 4004 in 21a is arranged as X1/Z1/X2/Z2/X3/Z3/X4/Z4/X5, and 4005 in 21b is arranged as Z1/X1/Z2/X2/Z3 /X3/Z4/X4/Z5.

Figure 22-26 corresponds to the arrangement diagram of the magnetoresistive sensing units of the Z-X axis magnetoresistive sensor. The 5000 shown in Figure 22 is a series of corresponding reference, push and pull magnetoresistive sensing units located in a strip-shaped soft magnetic flux concentrator , and the sensitive magnetoresistive sensing unit string is located between two occupied soft magnetic flux concentrators, or the sensitive magnetoresistive sensing unit string is located between an occupied soft magnetic flux concentrator and an idle soft magnetic flux concentrator, its magnetic resistance The arrangement order of the sensing unit strings is the second structure.

In 5001 shown in Figure 23 and 5002 shown in Figure 24, the reference magnetoresistance sensing unit string corresponds to a soft magnetic flux concentrator, the push and pull magnetoresistance sensing unit strings correspond to a common soft magnetic flux concentrator, and the sensitive magnetoresistance sensor string corresponds to a common soft magnetic flux concentrator. The sensing unit string corresponds to two occupied soft magnetic flux concentrators or one vacant soft magnetic flux concentrator and one occupied soft magnetic flux concentrator. In addition, there are vacant soft magnetic flux concentrators located at the junction and edge of X and Z to ensure the uniformity of the magnetic field. The arrangement sequence of the magnetoresistance sensing unit strings is X11/Z11/X12, or the staggered arrangement of Z21/X22/Z22, where X and Z correspond to multiple reference magnetoresistance sensing unit strings of the same type, and then they are arranged in a staggered manner.

In the 5003 shown in Figure 25 and the 5004 shown in Figure 26, the arrangement order of the magnetoresistive sensing unit strings is another way; Z31/X32/Z32/X32, or X41/Z41/X42/Z42 staggered arrangement, X and Z all correspond to a plurality of reference magnetoresistive sensing unit strings of the same type, and then are arranged in a staggered manner.

It should be pointed out that the push-pull magnetoresistance sensing unit area includes one or more push magnetoresistance sensing unit strings and one or more pull magnetoresistance sensing unit strings, and the reference sensitive magnetoresistance sensing unit area includes one or more pull magnetoresistance sensing unit strings. A plurality of strings of sensitive magnetoresistance sensing units, and one or more strings of reference magnetoresistance sensing units.

The gaps between the soft magnetic flux concentrators in the push-pull magnetoresistance sensing unit area are the same, and the gaps between the soft magnetic flux concentrators in the reference and sensitive magnetoresistance sensing unit areas are the same.

Embodiment six

Figures 27-29 are several structural diagrams corresponding to the back magnet, among which Figure 27 is a block-shaped back magnet, whose magnetization direction is along the height direction, and the magnetoresistive sensor is located on the N or S surface of one of the magnetic poles.

Figure 28 is a columnar back magnetic field, the magnetization direction of which is along the axial direction, and the magnetoresistive sensor is located on the N or S surface of one of the magnetic poles.

Figure 29 is a block-shaped back magnet with a groove on the surface, the magnetization direction is perpendicular to the bottom of the groove, and the magnetoresistive sensor is located above the surface with the groove.

Although the present application has been described by way of example, those of ordinary skill in the art know that there are many variations and changes in the application without departing from the spirit of the application, and it is intended that the appended claims cover these variations and changes without departing from the spirit of the application.

Claims (10)

1. A Z-X axis magneto-resistive sensor, Z-X axis magneto-resistive sensor is located with the plane of cut of device under test parallel and apart from the working plane of the predetermined clearance in the plane of cut, the sensitive direction of X axle magnetic field of Z-X axis magneto-resistive sensor is on a parallel with the plane of cut and along the tangential motion direction of the device under test, the sensitive direction of Z axle magnetic field of Z-X axis magneto-resistive sensor is perpendicular to the plane of cut, the device under test is gear or multipole, its characterized in that, Z-X axis magneto-resistive sensor is single-chip Z-X axis magneto-resistive sensor, includes:

the magnetic resistance sensor comprises a substrate positioned on an X-Y plane, a plurality of strip-shaped soft magnetic flux concentrators, a plurality of magnetic resistance sensing unit strings and a plurality of magnetic resistance sensing unit strings, wherein the long axis and the short axis of the substrate are respectively arranged in parallel along the Y, X direction, and the magnetic resistance sensing unit strings are positioned on the upper surface or the lower surface of the soft magnetic flux concentrators and are arranged in parallel along the Y direction;

the magnetoresistive sensing cell string includes: the magnetic field sensor comprises a reference magneto-resistance sensing unit string, a sensitive magneto-resistance sensing unit string, a push magneto-resistance sensing unit string, a pull magneto-resistance sensing unit string and a sensitive magneto-resistance sensing unit string, wherein the reference magneto-resistance sensing unit string is positioned on the Y-axis central line of the flux concentrator, the sensitive magneto-resistance sensing unit string is positioned at the gap of the Y-axis central line of the flux concentrator, the push magneto-resistance sensing unit string and the pull magneto-resistance sensing unit string are respectively positioned on two sides of the Y-axis central line of the flux concentrator and are equidistant to the Y-axis central line, the push magneto-resistance sensing unit string is electrically connected into a push arm, the pull magneto-resistance sensing unit string is electrically connected into a pull arm, the reference magneto-resistance sensing unit string is electrically connected into a reference arm, the sensitive magneto-resistance sensing unit string is electrically connected into a sensitive arm, and; the magneto-resistance sensing unit string of the reference bridge type X-axis sensor and the magneto-resistance sensing unit string of the push-pull bridge type Z-axis sensor are arranged in a staggered mode;

the magnetic resistance sensing unit forming the magnetic resistance sensing unit string is GMR or TMR magnetic resistance sensing unit, and comprises a seed layer, a lower electrode layer, a pinned layer, an isolation layer, a free layer, a bias layer, an upper electrode layer and a covering layer from bottom to top in sequence, wherein the isolation layer is made of Al₂O₃MgO or metal, the bias layer is an exchange bias layer or a permanent magnet bias layer;

the push-pull magnetoresistive sensing unit strings and the pull-magnetoresistive sensing unit strings occupy N push-pull magnetoresistive sensing unit regions R1, R2, … and RN, the reference magnetoresistive sensing unit strings and the sensitive magnetoresistive sensing unit strings occupy M reference sensitive magnetoresistive sensing unit regions P1, P2, … and PM, and the staggered arrangement mode is any one, two or three of the following combination modes, namely N is an integer and N is more than or equal to 1, and M is an integer and M is more than or equal to 1;

1) when N is M, (R1, P1), … (Ri, Pi) …, (RN, PM) or (P1, R1), … (Pi, Ri) …, (PM, RN);

2) n ═ 2i, M ═ 2i-1, then;

R1,(P1,R2),…(Pi-1,Ri),(Pi),(Ri+1,Pi+1),…(R2i-1,P2i-1),R2i；

or N ═ 2i-1, M ═ 2i, then;

P1,(R1,P2),…(Ri-1,Pi),(Ri),(Pi+1,Ri+1),…(P2i-1,R2i-1),P2i

3)N＝2j-1,M＝2j-2,

(R1,P1), …(Rj-1,Pj-1),Rj,(Pj,Rj+1),…,(P2j-2,R2j-1)

or M2 j-1, N2 j-2,

(P1,R1),…(Pj-1,Rj-1),Pi,(Rj,Pj+1),…,(R2j-2,P2j-1)；

i is an integer and is more than or equal to 1, and j is an integer and is more than or equal to 2.

2. A Z-X axis magnetoresistive sensor according to claim 1,

the pinned layer is located on a side of the pinning layer away from the isolation layer;

the exchange bias layer is positioned on one side of the free layer far away from the isolation layer;

the ferromagnetic material of at least one of the free layer, pinned layer, and bias layer is composed of a high permeability soft magnetic material including at least one of Fe, Co, Ni.

3. A Z-X axis magnetoresistive sensor according to claim 2, characterized in that the pinned layer magnetization direction is the X axis direction and the free layer magnetization direction is the Y axis direction.

4. The Z-X axis magnetoresistive sensor of claim 1, wherein the soft magnetic flux concentrators corresponding to the reference magnetoresistive sensing cell string, the push magnetoresistive sensing cell string, and the pull magnetoresistive sensing cell string are occupied soft magnetic flux concentrators, and the rest of the soft magnetic flux concentrators are vacant soft magnetic flux concentrators, and the reference magnetoresistive sensing cell string, the push magnetoresistive sensing cell string, and the pull magnetoresistive sensing cell string are located on the same occupied soft magnetic flux concentrator or on three occupied soft magnetic flux concentrators or two occupied soft magnetic flux concentrators respectively; the sensitive magneto-resistance sensing unit string is positioned between the two vacant soft magnetic flux concentrators, or positioned between the two occupied soft magnetic flux concentrators, or positioned between one vacant soft magnetic flux concentrator and one occupied soft magnetic flux concentrator.

5. A Z-X-axis magnetoresistive sensor according to claim 1, characterized in that the push-pull magnetoresistive sensing cell region comprises one or more push-pull magnetoresistive sensing cell strings and one or more pull-push magnetoresistive sensing cell strings, and the reference sensitive magnetoresistive sensing cell region comprises one or more sensitive magnetoresistive sensing cell strings and one or more sensitive magnetoresistive sensing cell strings.

6. A Z-X axis magnetoresistive sensor according to claim 5, characterized by the fact that the gaps between the soft magnetic flux concentrators in the push-pull magnetoresistive sensing cell area are the same and the gaps between the soft magnetic flux concentrators in the reference sensitive magnetoresistive sensing cell area are the same.

7. A Z-X axis magnetoresistive sensor according to claim 1,

the multiple magnetic poles comprise magnetic poles with magnetization parallel to the tangential direction, and two adjacent magnetic poles respectively have anti-parallel magnetization or clockwise and anticlockwise reverse magnetization,

or the included magnetic poles have the magnetization intensity perpendicular to the tangential plane direction, and two adjacent magnetic poles respectively have the anti-parallel magnetization intensity or the centripetal and centrifugal reverse magnetization intensity.

8. A Z-X axis magnetoresistive sensor according to claim 1, wherein the device under test further comprises a back magnet for providing a magnetic field to magnetize the gear; wherein,

the back magnet is a cuboid permanent magnet alloy material, the width and height directions of the back magnet are respectively along the X-axis magnetic field sensitive direction and the Z-axis magnetic field sensitive direction, and the magnetization direction of the back magnet is along the Z-axis magnetic field sensitive direction;

or,

the back magnet is made of a cylindrical permanent magnet alloy material, and the magnetization direction and the axial direction of the back magnet are along the sensitive direction of the Z-axis magnetic field;

or,

the back magnet is a square permanent magnet alloy material with a concave groove formed in the surface, the bottom surface of the concave groove is perpendicular to the Z-axis sensitive direction, and the magnetization direction is along the Z-axis magnetic field sensitive direction.

9. A Z-X axis magnetoresistive sensor according to claim 8, characterized in that the Z-X axis magnetoresistive sensor is located between the back magnet and the gear wheel and on the back magnet surface.

10. A Z-X axis magnetoresistive sensor according to claim 9,

the width of the back magnet is more than 0.5 time of the periodic interval of the gears;

or,

the specific clearance between the Z-X axis magneto-resistive sensor and the gear is more than 0.1 times and less than 1.0 times the gear period spacing.