JP2015021795A - Rotation sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotation sensor in which the accuracy of detecting the rotating state of a rotary body is improved.SOLUTION: The rotation sensor has a plurality of electromagnetic conversion units (10, 20) for converting a change in a magnetic flux cyclically changing in direction into an electric signal. Each of the plurality of electromagnetic conversion units has magneto-resistance effect elements constituting a pair (11-14, 21-24). Each of the magneto-resistance effect elements constituting a pair has a pin layer, a free layer, and an intermediate layer provided between the pin layer and the free layer. The magnetization directions of the pin layers possessed by the respective magneto-resistance effect elements constituting a pair differ in phase by 180° with each other. The magneto-resistance effect elements constituting a pair possessed by each of the plurality of electromagnetic conversion units are juxtaposed along the rotation direction of a rotary body and symmetrically arranged about a base line (BL) extending from the rotation shaft of the rotary body so as to cross the rotation direction at right angles, each of the magneto-resistance effect elements constituting a pair composing a bridge circuit, the midpoint potential of which is considered as a signal based on the rotating state of the rotary body.

Description

  The present invention relates to a rotation sensor that detects a rotation state of a rotating body based on a change in magnetic flux whose direction periodically changes as the rotating body rotates.

  Conventionally, for example, as shown in Patent Document 1, a magnetic member in which N poles and S poles are alternately arranged, and one or more pairs of vector detection type magnetoresistive effect elements facing the magnetic pole arrangement surface of the magnetic member, Have been proposed. One or a plurality of pairs of vector detection type magnetoresistive elements are arranged in a line substantially perpendicular to the magnetic pole arrangement direction of the magnetic member. Thereby, the phase of the magnetic flux which permeate | transmits all the vector detection type | mold magnetoresistive effect elements is the same.

JP 2006-23179 A

  In the magnetic position detection device described in Patent Document 1 described above, one or more pairs of vector detection type magnetoresistive effect elements are arranged in a line substantially perpendicular to the magnetic pole arrangement direction, and all the vector detection type magnetoresistance elements are arranged. The phase of the magnetic flux passing through the effect element is the same. However, in the case of this configuration, since the facing distance between each vector detection type magnetoresistive effect element and the magnetic member is different, the intensity of the magnetic flux passing through each vector detection type magnetoresistive effect element is different. Therefore, it may be difficult to detect the rotation state of the magnetic member (rotating body) with high accuracy based on an electric signal that depends on the resistance value of each vector detection type magnetoresistive element.

  In view of the above problems, an object of the present invention is to provide a rotation sensor with improved detection accuracy of the rotation state of a rotating body.

  In order to achieve the above-described object, the present invention provides a rotation sensor that detects a rotation state of a rotating body based on a change in magnetic flux whose direction periodically changes as the rotating body (200) rotates. , Having a plurality of magnetoelectric conversion units (10, 20) for converting a change in magnetic flux whose direction is periodically changed into an electric signal, and each of the plurality of magnetoelectric conversion units includes a pair of magnetoresistive effect elements (11-14, Each of the magnetoresistive effect elements having a pair of 21 to 24) includes a pinned layer having a fixed magnetization direction, a free layer whose magnetization direction varies according to an external magnetic field, and a pinned layer and a free layer. A non-magnetic intermediate layer provided on the pin layer, and having a property that the resistance value varies according to the magnetization direction of each of the pinned layer and the free layer. Magnetization directions are 180 ° different from each other, The pair of magnetoresistive effect elements included in each of the replacement parts are arranged side by side along the rotation direction of the rotating body, and are symmetrically arranged on a reference line (BL) extending perpendicularly to the rotation direction from the rotation axis of the rotating body. Each of the magnetoresistive effect elements forming a pair forms a bridge circuit, and the midpoint potential is a signal based on the rotation state of the rotating body.

  Thus, according to this invention, the magnetoresistive effect element (11-14, 21-24) is arrange | positioned along with the rotation direction. According to this, unlike the configuration in which the magnetoresistive effect elements (11 to 14, 21 to 24) are arranged in the direction perpendicular to the rotation direction instead of the rotation direction, each magnetoresistive effect element (11 -14, 21 to 24) have the same magnetic flux intensity. However, in the case of this configuration, the phases of magnetic fluxes transmitted through the magnetoresistive elements (11-14, 21-24) are different. However, as described above, a bridge circuit is formed by each of the magnetoresistive effect elements (11 to 14, 21 to 24) forming a pair, and the midpoint potential is set as a signal based on the rotation state of the rotating body (200). Phase shift can be eliminated. Hereinafter, the reason will be described by taking as an example a configuration in which a half bridge circuit is assembled by a pair of magnetoresistive elements (11, 12).

  The angle around the intersection from the reference line (BL) of the reference magnetic flux passing through the intersection (CP) between the parallel direction in which the magnetoresistive elements (11, 12) forming a pair and the reference line (BL) are arranged is a, The angle deviation from the reference magnetic flux in the direction of the magnetic flux passing through the center of the resistance effect element (11, 12) is b, the center value of the resistance value of each of the magnetoresistive effect elements (11, 12) forming a pair is Rc, and the pair is When the amplitude of the resistance change amount of each magnetoresistive element (11, 12) formed is R0, and the voltage supplied to the bridge circuit is V, the midpoint potential of the bridge circuit is (R0 × sin (ab) + Rc). V / (R0 × sin (ab) + Rc + R0 × sin (a + b + 180 °) + Rc). To summarize this, the midpoint potential of the bridge circuit is (−V / 2) (sin (a) × cos (b) / (cos (a) × sin (b) −Rc) −1). , (Sin (a) × cos (b) / (cos (a) × sin (b) −Rc) −1).

  Here, since b and Rc are constant in time, sin (b), cos (b), and Rc each have a constant value. For this reason, the above-described formula depends only on a in terms of time. As described above, even if the phases of the magnetic fluxes transmitted through the magnetoresistive elements (11, 12) are different, the midpoint potential of the bridge circuit has a value in which the phase shift is eliminated. Therefore, this midpoint potential is utilized as a signal based on the rotation state of the rotating body (200). By doing so, the detection accuracy of the rotating state of the rotating body (200) is improved.

  In addition, although the elements described in the claims and the means for solving the problems are attached with parentheses, the parentheses are attached to each component described in the embodiment. This is to simply show the correspondence with the elements, and does not necessarily indicate the elements themselves described in the embodiments. The description of the reference numerals with parentheses does not unnecessarily narrow the scope of the claims.

It is a perspective view which shows roughly the position of the rotation sensor which concerns on 1st Embodiment, and a rotary body. It is a top view which shows the position of a rotation sensor and a rotary body roughly. It is a schematic diagram which shows the magnetization direction of a pin layer. It is a circuit diagram which shows the bridge circuit assembled by the magnetoresistive effect element. It is a timing chart which shows a midpoint potential and a pulse signal. It is a schematic diagram which shows the reference | standard magnetic flux which penetrates an intersection. It is a graph which shows a magnetoresistive effect element and the fluctuation | variation of each resistance value of a middle point. It is a top view which shows the modification of a magnetoelectric conversion part. It is a top view which shows the modification of a magnetoelectric conversion part. It is a top view which shows the modification of a magnetoelectric conversion part. It is a circuit diagram which shows a 1st full bridge circuit. It is a circuit diagram which shows a 2nd full bridge circuit.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
Based on FIGS. 1-7, the rotation sensor which concerns on this embodiment is demonstrated. In the following, a plane at the same height position where the rotator 200 and the rotation sensor 100 are arranged is defined as a specified plane, and a direction perpendicular to the specified plane and passing through the rotation center RC of the rotator 200 is referred to as an axial direction. A direction around the axial direction is indicated as a rotation direction, and a direction extending from the rotation center RC along the prescribed plane is indicated as a radial direction. In addition, the rotating shaft described in the claims is along the axial direction.

  The rotation sensor 100 detects the rotation state of the rotating body 200 based on a change in magnetic flux whose direction periodically changes as the rotating body 200 rotates. The rotating body 200 has an annular shape, and magnetic poles 210 and 220 are formed on the outer ring surface at equal intervals along the rotation direction. As shown in FIGS. 1 and 2, different magnetic poles 210 and 220 are alternately formed, and a magnetic flux flows from the N pole 210 to the S pole 220. The magnetic flux between the adjacent magnetic poles 210 and 220 flows so as to draw a semicircular locus. The rotation sensor 100 detects a periodic change due to the rotation of the magnetic flux that draws this semicircular locus.

  The rotation sensor 100 includes magnetoelectric conversion units 10 and 20 that convert changes in the direction of magnetic flux into electrical signals. The 1st magnetoelectric conversion part 10 has the magnetoresistive effect elements 11 and 12 which make a pair, and the 2nd magnetoelectric conversion part 20 has the magnetoresistive effect elements 21 and 22 which make a pair. The magnetoresistive effect elements 11 and 12 forming a pair and the magnetoresistive effect elements 21 and 22 forming a pair are arranged side by side along the rotation direction as shown in FIGS. Are symmetrically arranged on a reference line BL extending in the radial direction from the center. The magnetoresistive elements 11 and 12 forming a pair are rotated in the rotational direction (strictly speaking, the rotation of the rotating body 200 at the intersection CP in the rotational direction where the reference line BL and the magnetoresistive elements 11 and 12 are arranged). The magnetoresistive elements 21 and 22 forming a pair are arranged in the rotational direction (strictly, the tangential direction) via the magnetoresistive elements 11 and 12. The parallel direction described in the claims corresponds to the tangential direction described above.

  In the present embodiment, the lateral widths of the magnetoresistive elements 11, 12, 21, and 22 in the rotational direction are the same. Therefore, if the lateral width of the magnetoresistive effect elements 11, 12, 21, and 22 is L, the center of each of the magnetoresistive effect elements 11 and 12 is L / 2 in the rotational direction (tangential direction) from the reference line BL (intersection CP). It is separated. The centers of the magnetoresistive elements 21 and 22 are separated from the reference line BL (intersection CP) by 3L / 2 in the rotational direction (tangential direction). Thus, each of the magnetoresistive effect elements 11, 12, 21, and 22 is separated from the reference line BL (intersection CP) by the width. Therefore, there is a phase difference between the magnetic flux that passes through the centers of the magnetoresistive elements 11, 12, 21, and 22 and the magnetic flux that passes through the intersection CP.

  As shown in FIG. 2, the magnetoresistive effect elements 11 and 21 are located on the left side of the drawing with respect to the reference line BL, and the magnetoresistive effect elements 12 and 22 are located on the right side of the drawing with respect to the reference line BL. Therefore, when the rotating body 200 rotates counterclockwise, the magnetoresistive effect elements 11 and 21 are positioned upstream of the reference line BL, and the magnetoresistive effect elements 12 and 22 are positioned downstream of the reference line BL. It becomes. Therefore, the magnetic flux that passes through the magnetoresistive effect element 21 has a phase that is 3L / 2 faster than the reference magnetic flux that passes through the reference line BL, and the magnetic flux that passes through the magnetoresistive effect element 11 has a phase that is L / 2 faster than the reference magnetic flux. Become. On the contrary, the magnetic flux passing through the magnetoresistive effect element 12 is delayed in phase by L / 2 than the reference magnetic flux, and the magnetic flux passing through the magnetoresistive effect element 22 is delayed in phase by 3 L / 2 from the reference magnetic flux. . On the contrary, when the rotating body 200 rotates clockwise, the magnetoresistive effect elements 12 and 22 are located upstream from the reference line BL, and the magnetoresistive effect elements 11 and 21 are located downstream from the reference line BL. Will be located. Therefore, the magnetic flux that passes through the magnetoresistive effect element 22 has a phase that is 3L / 2 faster than the reference magnetic flux, and the magnetic flux that passes through the magnetoresistive effect element 12 has a phase that is L / 2 faster than the reference magnetic flux. On the contrary, the magnetic flux passing through the magnetoresistive effect element 11 is delayed in phase by L / 2 from the reference magnetic flux, and the magnetic flux passing through the magnetoresistive effect element 21 is delayed in phase by 3 L / 2 from the reference magnetic flux. In the present embodiment, the case where the rotating body 200 rotates counterclockwise will be described. When the rotating body 200 rotates clockwise, the above-described relationship is established, and thus the description thereof is omitted.

  Although not shown, each of the magnetoresistive effect elements 11, 12, 21, and 22 includes a pinned layer having a fixed magnetization direction, a free layer whose magnetization direction varies according to an external magnetic field, and a pinned layer and a free layer. And a nonmagnetic intermediate layer provided on the substrate. The resistance value fluctuates depending on the magnetization direction of each of the pinned layer and the free layer. Highly fluctuating. In the present embodiment, the intermediate layer has conductivity, and each of the magnetoresistive elements 11, 12, 21, and 22 is a giant magnetoresistive element.

  The magnetization directions of the pinned layers of each of the magnetoresistive effect elements 11, 12, 21, and 22 are along the prescribed plane, and the magnetization directions of the pinned layers of each of the magnetoresistive effect elements 11 and 12 forming a pair are in the radial direction. The magnetization direction of the pinned layer of each of the magnetoresistive effect elements 21 and 22 that form a pair is along the rotational direction (strictly, the tangential direction thereof). Therefore, the magnetization direction of the pinned layer included in each of the magnetoresistive effect elements 11 and 12 forming a pair is different from the magnetization direction of the pinned layer included in each of the magnetoresistive effect elements 21 and 22 forming a pair by 90 ° (270 °). Yes. In addition, the magnetization directions of the pin layers of the magnetoresistive elements 11 and 12 forming a pair are different from each other by 180 °, and the magnetization directions of the pin layers of the magnetoresistive elements 21 and 22 forming a pair are different from each other by 180 °. Yes.

  As shown in FIG. 3, when the magnetization direction is expressed by a clockwise angle θ from the reference line BL along the radial direction, the magnetoresistive effect element 11 has a magnetization direction of the pinned layer of 0 °, and the magnetoresistive effect element 12 is The magnetization direction of the pinned layer is 180 °. The magnetoresistive element 21 has a pinned layer with a magnetization direction of 90 °, and the magnetoresistive element 22 has a pinned layer with a magnetization direction of 270 °. Thus, the magnetization directions of the magnetoresistive effect elements 11 and 12 forming a pair are antiparallel to each other, and the magnetization directions of the magnetoresistive effect elements 21 and 22 forming a pair are antiparallel to each other. For this reason, when the resistance values of the two magnetoresistive elements are opposite to each other and one of the two magnetoelectric transducers has a small resistance value, the other resistance value is large.

  As shown in FIG. 4, a bridge circuit is formed by the magnetoresistive effect elements 11 and 12 and the magnetoresistive effect elements 21 and 22 that form a pair, and the midpoint potential is changed to the rotational state of the rotating body 200. As a signal based on this, it is input to a processing circuit (not shown) located in the subsequent stage. The first half-bridge circuit is assembled by the magnetoresistive effect elements 11 and 12 that form a pair of the first magnetoelectric conversion unit 10, and the magnetoresistive effect element 21 that forms a pair of the second magnetoelectric conversion unit 20. , 22 form a second half bridge circuit. As described above, the magnetization direction of the pinned layer included in each of the paired magnetoresistive effect elements 11 and 12 and the magnetization direction of the pinned layer included in each of the paired magnetoresistive effect elements 21 and 22 are 90 ° (270 °). ) Is different. Therefore, the phase difference between the midpoint potential of the first half bridge circuit (hereinafter referred to as the first midpoint potential) and the midpoint potential of the second half bridge circuit (hereinafter referred to as the second midpoint potential) is 90 °. (270 °). Therefore, if the first midpoint potential is a sine wave, the second midpoint potential is a cosine wave. The processing circuit described above has a threshold value (broken line shown in FIG. 5). By comparing this threshold value with the midpoint potential, the first midpoint potential is set as the first pulse signal, and the second midpoint potential is set as the second potential. Convert to 2-pulse signal.

  Hereinafter, the characteristic points of the rotation sensor 100 and the operation and effects thereof will be described with reference to FIGS. 6 and 7. As described above, the magnetoresistive effect elements 11, 12, 21, and 22 are arranged side by side along the rotation direction (the tangential direction of the intersection CP). According to this, unlike the configuration in which a plurality of magnetoresistive elements are arranged in the radial direction perpendicular to the rotational direction instead of the rotational direction, the strength of the magnetic flux transmitted through each magnetoresistive element is the same. It becomes. However, in the case of this configuration, as described above, due to its own lateral width, there is a phase difference between the magnetic flux passing through the magnetoresistive effect elements 11, 12, 21, and 22 and the reference magnetic flux passing through the intersection CP.

  As shown in FIG. 6, the angle around the intersection CP from the reference line BL in the reference magnetic flux is defined as a. When the center of the magnetoresistive effect element 11 is at the intersection CP, the resistance value of the magnetoresistive effect element 11 constituting the first half bridge circuit (hereinafter referred to as the first resistance value) is as shown by a broken line in FIG. The behavior of a sine wave depending on the angle a is shown. However, since the center of the magnetoresistive effect element 11 is deviated from the intersection CP, the first resistance value exhibits a behavior in which the phase is deviated from the sine wave as shown by the solid line in FIG. Similarly, when the center of the magnetoresistive effect element 12 is at the intersection CP, as indicated by a broken line in FIG. 7, the resistance value of the magnetoresistive effect element 12 constituting the first half bridge circuit (hereinafter referred to as the second resistance value). Indicates a behavior of a cosine wave depending on the angle a. However, since the center of the magnetoresistive effect element 12 is deviated from the intersection CP, the second resistance value exhibits a behavior in which the phase is deviated from the cosine wave as shown by the solid line in FIG.

  As described above, each of the first resistance value and the second resistance value behaves with a phase shift from the angle a. The same applies to the resistance values of the magnetoresistive elements 21 and 22 constituting the second half bridge circuit. However, as described above, the first half bridge circuit is assembled by the magnetoresistive effect elements 11 and 12 forming a pair, the second half bridge circuit is assembled by the magnetoresistive effect elements 21 and 22 forming the pair, and the midpoint potential is rotated. The signal is based on the rotation state of the body 200. According to this, the phase shift can be eliminated for the following reason.

  As described above, the angle of the reference magnetic flux is a. An angle deviation from the reference magnetic flux in the direction of the magnetic flux passing through the centers of the paired magnetoresistive elements 11 and 12 is defined as b. Further, the center value of the resistance value of each of the magnetoresistive effect elements forming the pair is Rc, the amplitude of the resistance change amount of each of the magnetoresistive effect elements 11 and 12 forming the pair is R0, and the voltage supplied to the first half bridge circuit is V Then, the first midpoint potential is expressed as (R0 × sin (ab) + Rc) V / (R0 × sin (ab) + Rc + R0 × sin (a + b + 180 °) + Rc). To summarize this, the midpoint potential of the first half-bridge circuit is (−V / 2) (sin (a) × cos (b) / (cos (a) × sin (b) −Rc) −1). This corresponds to the resistance at the midpoint of the first half-bridge circuit (hereinafter referred to as the first midpoint resistance) (sin (a) × cos (b) / (cos (a) × sin (b) − It can be seen that it depends on Rc) -1).

  Here, since b and Rc are constant in time, sin (b), cos (b), and Rc each have a constant value. For this reason, the first midpoint resistance depends only on a in terms of time, and FIG. 7 shows the behavior indicated by the alternate long and short dash line. That is, it shows behavior similar to a sine wave without phase shift. As described above, even if the phases of the magnetic fluxes transmitted through the paired magnetoresistive elements 11 and 12 are different, the first midpoint potential is a value at which the phase shift is eliminated. Therefore, by using the first midpoint potential as a signal based on the rotation state of the rotator 200, the detection accuracy of the rotation state of the rotator 200 is improved.

  Of course, the same argument can be applied to the magnetoresistive effect elements 21 and 22 forming a pair. In this case, the same argument can be advanced by setting the angle deviation from the reference magnetic flux in the direction of the magnetic flux passing through the centers of the paired magnetoresistive effect elements 21 and 22 to c. The resistance at the midpoint (hereinafter referred to as the second midpoint resistance) is a value with no phase shift. Therefore, by using the second midpoint potential as a signal based on the rotation state of the rotator 200, the detection accuracy of the rotation state of the rotator 200 is improved.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  In the present embodiment, the magnetoresistive effect elements 11 and 12 forming a pair are arranged in the rotational direction (tangential direction) without any intervening therebetween, and the magnetoresistive effect elements 21 and 22 forming the pair are magnetoresistive effect elements 11 and 12. In the example shown in FIG. However, as shown in FIG. 8, the magnetoresistive elements 21 and 22 forming a pair are arranged in the rotational direction (tangential direction) without any intervening elements, and the magnetoresistive elements 11 and 12 forming a pair are magnetoresistive elements. It is also possible to adopt a configuration in which the rotation direction (tangential direction) is arranged via 21 and 22.

  In the present embodiment, the first magnetoelectric conversion unit 10 includes a pair of magnetoresistive effect elements 11 and 12, and the second magnetoelectric conversion unit 20 includes a pair of magnetoresistive effect elements 21 and 22. An example is shown. However, the number of pairs of magnetoresistive effect elements forming a pair included in each of the magnetoelectric conversion units 10 and 20 is not limited to the above example, and a plurality of pairs may be used. For example, as shown in FIGS. 9 and 10, the first magnetoelectric conversion unit 10 has magnetoresistive effect elements 11 to 14 forming two pairs, and the second magnetoelectric conversion unit 20 forms magnetoresistives forming two pairs. A configuration having the effect elements 21 to 24 can also be adopted. In this case, as shown in FIG. 11 and FIG. 12, two first half bridge circuits are assembled by the magnetoresistive effect elements 11 to 14 forming two pairs, and the first full bridge circuit is assembled by these. In addition, two second half-bridge circuits are formed by the magnetoresistive effect elements 21 to 24 forming two pairs, and the second full-bridge circuit is formed by these.

  In the present embodiment, an example in which the lateral widths in the rotation direction of the magnetoresistive elements 11, 12, 21, and 22 are the same is shown. However, the lateral widths in the rotational direction (tangential direction) of the magnetoresistive elements forming a pair are equal and the distances from the reference line BL (intersection CP) of the magnetoresistive elements forming the pair may be equal. Therefore, the lateral widths of all the magnetoresistive elements need not be equal.

  In the present embodiment, an example is shown in which the intermediate layer has conductivity, and each of the magnetoresistive effect elements 11, 12, 21, and 22 is a giant magnetoresistive effect element. However, it is also possible to adopt a configuration in which the intermediate layer has insulating properties and each of the magnetoresistive effect elements 11, 12, 21, and 22 is a tunnel magnetoresistive effect element.

DESCRIPTION OF SYMBOLS 10,20 ... Magnetoelectric conversion part 11,12,21,22 ... Magnetoresistive effect element 100 ... Rotation sensor 200 ... Rotating body

Claims (4)

A rotation sensor that detects a rotation state of the rotating body based on a change in magnetic flux whose direction periodically changes as the rotating body (200) rotates.
Having a plurality of magnetoelectric converters (10, 20) for converting a change in magnetic flux whose direction periodically changes into an electric signal;
Each of the plurality of magnetoelectric conversion units has a pair of magnetoresistive effect elements (11 to 14, 21 to 24),
Each of the pair of magnetoresistive effect elements includes a pinned layer having a fixed magnetization direction, a free layer whose magnetization direction varies according to an external magnetic field, and a non-layer provided between the pinned layer and the free layer. A magnetic intermediate layer, having a property that the resistance value varies according to the magnetization direction of each of the pinned layer and the free layer,
The magnetization directions of the pinned layers of each of the magnetoresistive effect elements forming a pair are different from each other by 180 °,
The magnetoresistive effect elements forming a pair included in each of the plurality of magnetoelectric conversion units are arranged side by side along the rotation direction of the rotating body and extend from the rotation axis of the rotating body so as to be orthogonal to the rotation direction. It is arranged symmetrically with the line (BL),
A rotation sensor, wherein a bridge circuit is formed by each of the magnetoresistive effect elements forming a pair, and a midpoint potential thereof is used as a signal based on a rotation state of the rotating body.   The angle around the intersection from the reference line of the reference magnetic flux that passes through the intersection (CP) between the parallel direction in which each of the magnetoresistive elements forming a pair and the reference line passes is a, and the center of the magnetoresistive effect element is Assuming that the angle deviation from the reference magnetic flux in the direction of the magnetic flux to be transmitted is b and the center value of the resistance value of each of the magnetoresistive elements forming a pair is Rc, the midpoint potential of the bridge circuit is sin (a) × The rotation sensor according to claim 1, wherein the rotation sensor depends on cos (b) / (cos (a) × sin (b) −Rc) −1. As the plurality of magnetoelectric converters, a first magnetoelectric converter in which the magnetization direction of the pinned layer extends along a radial direction orthogonal to the rotation axis, and the magnetization direction of the pinned layer is orthogonal to the tangential direction of rotation of the rotating body A second magnetoelectric converter,
A first half bridge circuit is assembled by a pair of magnetoresistive effect elements (11, 12) included in the first magnetoelectric conversion unit, and a pair of magnetoresistive effect included in the second magnetoelectric conversion unit. The rotation sensor according to claim 2, wherein the second half-bridge circuit is assembled by the elements (21, 22). Two of the first half bridge circuits are assembled by the magnetoresistive effect elements (11 to 14) forming two pairs of the first magnetoelectric conversion unit, and the first full bridge circuit is assembled by these,
Two second half bridge circuits are assembled by two pairs of magnetoresistive effect elements (21 to 24) of the second magnetoelectric conversion unit, and the second full bridge circuit is assembled by these. The rotation sensor according to claim 3.

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