JP3610420B2 - Magnetic sensor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a magnetic sensor using a magnetoresistive effect element.
[Prior art]
In general, in an automation machine apparatus in factory automation, office automation, and other fields, an optical or magnetic encoder is used to obtain an accurate position of a linear or rotary moving body. Of these, magnetic encoders are widely used because of their simple structure and their advantage for environmental conditions such as water resistance and oil resistance. Taking this magnetic rotary encoder as an example, this encoder is composed of a rotating drum magnetized at a predetermined pitch and a magnetic sensor arranged so as to oppose it, for example, a magnetoresistive effect element provided in this magnetic sensor. The relative or absolute position is obtained by processing the relative or absolute position by processing the output waveform.
[0002]
More specifically, FIG. 6 is a perspective view showing a general configuration of a magnetic rotary encoder. The encoder is a rotary drum 4 fixed to a rotary shaft 2 to be detected as a rotational position, and the drum. The magnetic sensor 6 is mainly composed of a magnetic sensor 6 disposed at a predetermined interval (spacing) so as to face the outer peripheral surface. A multipolar magnetic pattern 8 having N and S poles magnetized at a predetermined pitch λ is provided on the outer peripheral surface of the rotating drum 4. FIG. 7 shows a developed view of the multipolar magnetic pattern. The magnetic sensor 6 includes two magnetoresistive elements R1 arranged at a substantially half interval of the pitch λ, that is, at a substantially λ / 2 interval. , R2 so that a change in the magnetic field accompanying the rotation of the rotating drum 4 can be detected.
Here, the distance between the elements R1 and R2 is substantially λ / 2. In some cases, the distance between the elements is set to λ / 2 with high accuracy, or in Japanese Patent Laid-Open No. 1-318914. Including the point that the distance between the elements R1 and R2 may be set based on a temporary pitch determined when a distance between the drum and the sensor, that is, a circle in contact with the sensor is assumed in consideration of the spacing as shown in the publication The term “substantial” is used.
This magnetoresistive element, that is, the MR elements R1 and R2, is formed by a technique such as vapor deposition of a material whose electrical resistance changes depending on the strength of the magnetic field on the surface of a glass substrate, for example, a thin film such as Ni · Fe or Ni · Co. Forming.
[0003]
Next, the operation principle of the MR element will be described with reference to FIG.
The resistance change with respect to the magnetic field of this type of MR element has the characteristics shown in FIG. 8A. The resistance changes in proportion to the magnitude of the magnetic field regardless of the direction of the magnetic field, and is saturated at a certain value. To do. Here, it is assumed that the rotating drum 4 rotates and a magnetic field B whose magnitude changes in a sine wave shape as shown in FIG. 8B is applied to the MR elements R1 and R2.
When such a magnetic field B is applied to the MR elements R1 and R2, the resistance values are similar to the half-wave rectified waveform with the pitch λ (FIG. 8C), and naturally the resistance waveforms of the MR elements R1 and R2 are The phase difference is λ / 2.
Therefore, when these MR elements R1 and R2 are connected in series as shown in FIG. 8D and the voltage V is applied from the detection DC power supply 10, the output ea can be taken out from the connection point. As the output waveform at this time, a substantially sine wave output with a period of λ can be obtained as shown in FIG.
[0004]
The above explanation is the principle of detecting the change in the magnetic field, but in practice, the resistance change amount of the MR element is as small as about 2%, and the incremental phase for obtaining the relative rotation amount or rotation angle is taken into consideration. For example, in order to recognize forward / reverse rotation, two signals of A phase and B phase are required.
Therefore, as shown in FIG. 9, eight MR elements RA, RB, Ra, Rb, Ra ′, Rb ′, RA ′, and RB ′ are used and are sequentially arranged at intervals of ¼λ, respectively. As shown in FIG. As a matter of course, the interval between the A-phase MR element and the B-phase MR element is set to an odd multiple of λ / 4.
[0005]
Here, since the four MR elements RA, RB, Ra, Rb on the left side in the figure are connected to the plus side of the detection DC power supply, they are configured as plus side magnetoresistive elements, while the four MR elements on the right side in the figure are configured. Since the elements Ra ′, Rb ′, RA ′, and RB ′ are connected to the minus side (ground), they are configured as minus side magnetoresistive elements. Here, the MR elements RA, RA ′, Ra and Ra ′ output A phase side signals, and the MR elements RB, RB ′, Rb and Rb ′ output B phase signals. Each pair of MR elements, for example, RA and RA ′, Ra and Ra ′, RB and RB ′, and Rb and Rb ′ have the relationship of the MR elements R1 and R2 described above. Are substantially spaced apart at an interval of (λ / 2) × odd times.
The MR elements RA, RA ′, Ra, Ra ′ for A-phase signals are connected in a bridge shape (see FIG. 10A), and both connection points V _A , V _a are made of, for example, operational amplifiers A By inputting to the negative terminal and the positive terminal of the phase side amplifier 12 respectively, the outputs of both connection points V _A and V _a are differentially amplified. This compensates for the small amount of resistance change of the MR element.
[0006]
Similarly, MR elements RB, RB ′, Rb, Rb ′ for B-phase signals are also connected in a bridge shape (see FIG. 10B), and both connection points V _B , V _b are connected to the B-phase side amplifier. By inputting the signals to the negative terminal 14 and the positive terminal 14 respectively, the outputs of both connection points V _B and V _b are differentially amplified. Further, by arranging the MR element for the A phase signal and the MR element for the B phase signal substantially at intervals of 1 / 4λ in this way, ideally, as shown in FIG. And the B phase signal are output with the electrical angle being 90 ° out of phase, and the phase that advances according to the forward and reverse rotation direction changes, so that it recognizes whether it is forward rotation or reverse rotation. .
[0007]
[Problems to be solved by the invention]
By the way, when the positional relationship between the rotating drum 4 and the magnetic sensor 6 is enlarged as shown in FIG. 12, due to the curvature of the rotating drum 4, the distance between the center of the magnetic sensor 6 and the drum 4 ( The spacing g1 and the distance g2 between the peripheral portion of the sensor 6 and the drum 4 are slightly different, but due to this distance difference, the output waveform of the MR element does not become a sine wave. A sine wave as shown in A) becomes a slightly distorted waveform. When this distorted wave is analyzed, as shown in FIG. 13B, in addition to the fundamental wave 16 having the wavelength λ, the third harmonic 18 having a wavelength of λ / 3 is mainly included. As a result, the output waveform is greatly distorted as described above. This is not a problem when the curvature of the rotating drum 4 is small with respect to the length L of the sensor 6 or when the detection accuracy does not need to be so high. It is necessary to cancel the third harmonic component and remove the distortion.
[0008]
Therefore, as shown in FIG. 14, the distance between the MR elements Rb and Ra ′ is further increased by half the wavelength λ / 3 of the third harmonic, that is, λ / 6, so that the four The MR elements Ra ′, Rb ′, RA ′, and RB ′ are shifted to the right by a distance λ / 6. Conversely, it may be shifted leftward by a distance λ / 6. As a result, as shown in FIG. 13C, the right four MR elements Ra ′, Rb ′, RA ′, and RB ′ generate a waveform shifted by λ / 6, and the third harmonic 18 ′ is shown in the above diagram. Since the phase is shifted by ½ wavelength with respect to the third harmonic wave 18 shown in FIG. 13 (B), both the third harmonic waves 18 and 18 ′ cancel each other, and as a result, FIG. As shown in FIG. 4, it is possible to suppress distortion of the output waveform to some extent.
[0009]
However, in a field where higher positioning accuracy is required, such as a semiconductor manufacturing apparatus, it is not sufficient to cancel the third harmonic as described above, and further distortion removal is required. ing. For example, when the A-phase and B-phase signals whose distortion is suppressed by the operation as described above are evaluated as Lissajous waveforms, the difference between the maximum distance ra and the minimum distance ri from the center is expressed as shown in FIG. The distortion rate (ra-ri) / ra is about 7%, for example, and it is desired to further reduce this distortion rate. In addition, the perfect circle shown with a broken line in FIG. 15 shows an ideal waveform without distortion.
The present invention has been devised to pay attention to the above problems and to effectively solve them. An object of the present invention is to provide a magnetic sensor with less distortion of an output waveform.
[0010]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a magnetic sensor disposed opposite to a rotating drum having a multipolar magnetic pattern in which N and S poles are magnetized at a predetermined pitch λ, and detecting DC A plurality of positive side magnetoresistive effect elements connected to the positive side of the power source and a plurality of negative side magnetoresistive effect elements connected to the negative side of the detection DC power source have a specific pitch along the rotation direction of the rotating drum. in the magnetic sensor are arranged, as well as arranged alternately with the positive magnetoresistance effect element and the minus side magnetoresistive element next to each other, the positive magnetoresistance effect element and the minus side magnetoresistive element Has two each for A phase and B phase, and the interval between the magnetoresistive effect element for A phase and the magnetoresistive effect element for B phase is set to an odd multiple of λ / 4. The four magnetoresistive elements for each of the phases for A phase and B phase are connected to each other in a differential manner in a bridge shape for each phase, and between the magnetoresistive elements connected in series in the bridge The distance is configured to be set to a distance for canceling the harmonic component .
[0011]
As a result, the plus-side magnetoresistive effect element and the minus-side magnetoresistive effect element are alternately arranged, so that the total length of the element arrangement portion can be shortened to about half as compared with the conventional sensor. It becomes possible. Therefore, the difference between the distance between the central part of the sensor and the rotating drum and the distance between the sensor peripheral part and the rotating drum can be further reduced. can be further suppressed distortion less and output waveform difference of the magnetic field strength and that Do.
[0012]
The distance between the magnetoresistive element are connected in series in the bridge, the value of substantially lambda / 2 × odd multiple ± lambda / 6 The distances to cancel a third harmonic component If e Example At this time, the distance between the elements connected to the position that is the opposite side of the bridge is substantially λ / 6. In order to cancel the second harmonic component, both elements are arranged at a distance that is substantially an odd multiple of λ / 2, and at this time, they are connected to the position that is the opposite side of the bridge. The distance between the elements is such that the two elements are at substantially the same position.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a magnetic sensor according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a diagram showing an arrangement state of magnetoresistive elements of a magnetic sensor according to the present invention. The same parts as those of the conventional magnetic sensor described above are denoted by the same reference numerals.
As shown in FIG. 1, this magnetic sensor 20 also has eight magnetoresistive (hereinafter referred to as MR) elements RA, RB, Ra, Rb, Ra ′ as described in FIG. 9 or FIG. , Rb ′, RA ′, and RB ′, which are arranged at a pitch as described later along the rotation direction of the multipolar magnetic pattern 8 of the rotary drum 4.
[0014]
Each of the MR elements has one end connected to a detection DC power source and a positive voltage V applied thereto, plus MR elements RA, RB, Ra, and Rb, and one end connected to the minus side (ground) of the power source. The negative side MR elements Ra ′, Rb ′, RA ′, and RB ′ are classified into two. Further, each of these MR elements requires two signals of the A-phase signal and the B-phase signal in order to recognize the forward / reverse rotation of the rotating drum as described above. ', Ra, Ra' and B-phase MR elements RB, RB ', Rb, Rb'.
These MR elements are connected in the same manner as described above with reference to FIG. That is, as shown in FIG. 10A, the MR elements RA and RA ′ on the A phase side and Ra and Ra ′ are connected in series, and output from the respective connection points V _A and V _{a of} both elements. Take out.
[0015]
These four MR elements RA, RA ′, Ra, Ra ′ are bridge-connected, and the detection DC power supply 10 is connected to the upper and lower ends in the figure. In this case, as described above, the plus side MR elements RA and Ra are connected to the plus side of the power supply 10 and the minus side MR elements RA ′ and Ra ′ are connected to the minus side, respectively. The outputs of both connection points V _A and V _a are respectively input to the minus terminal and the plus terminal of the A-phase side amplifier 12, whereby the outputs are differentially amplified to obtain an A-phase signal.
Further, as shown in FIG. 10B, the MR elements RB and RB ′ on the B phase side and Rb and Rb ′ are also connected in series, and output from respective connection points V _B and V _{b of} both elements. Take out. These four MR elements RB, RB ′, Rb, Rb ′ are bridge-connected, and a detection DC power source 10 is connected to the upper and lower ends in the figure. Also in this case, as described above, the plus side MR elements RB and Rb are connected to the plus side of the power source 10 and the minus side MR elements RB ′ and Rb ′ are connected to the minus side. By inputting the outputs of both connection points V _B and V _b to the negative terminal and the positive terminal of the B-phase side amplifier 14 respectively, both outputs are differentially amplified to obtain a B-phase signal.
[0016]
On the other hand, as shown in FIG. 1, each MR element is arranged such that four plus-side MR elements RA, RB, Ra, Rb and four minus-side MR elements Ra ′, Rb ′, RA ′, RB ′ are adjacent to each other. Alternatingly arranged to fit. That is, the four MR elements Ra ′, Rb ′, RA ′, RB ′ on the right side in the drawing are inserted in a comb-tooth shape between the four MR elements RA, RB, Ra, Rb on the left side in the drawing shown in FIG. Arranged as if. That is, the arrangement of the eight MR elements can be substantially accommodated within the pitch λ of the multipolar magnetic pattern 8. Here, adjacent MR elements, that is, RA and Ra ′, RB and Rb ′, Ra and RA ′, and Rb and RB ′, as shown in FIG. It is in a positional relationship. As a matter of course, the intervals between the plus side MR elements RA, RB, Ra, Rb are substantially set to λ / 4 when the pitch of the multipolar magnetic pattern 8 is λ, and similarly, the minus side MR element Ra. The interval between ', Rb', RA 'and RB' is also substantially set to λ / 4. Here, the term “substantial” means that the distance between the drum and the sensor, that is, a temporary pitch when considering the spacing is included as described above. That is, the pitch of N and S on the circumference whose radius is a value obtained by adding the spacing distance to the radius of the drum is a temporary pitch. The following terms are also synonymous.
[0017]
Then, adjacent MR elements that are in a positional relationship that is the opposite side of the bridge circuit, that is, between the elements RA and Ra ′, between RB and Rb ′, between Ra and RA ′, and between Rb and RB ′ are substantially each. The pitch is set to λ / 6, and the third harmonic component can be canceled. Incidentally, the distance between adjacent MR elements on the opposite side, for example, Ra ′ and RB, is substantially λ / 12 (= λ / 4−λ / 6).
Here, although the value of the pitch λ is about 2 mm, the width of each MR element is about 20 μm, which is very narrow with respect to the pitch λ. Therefore, the width of the MR element is hardly considered here. It's okay. Of course, the pitch λ and the width of the MR element are not limited to this.
[0018]
In the magnetic sensor configured as described above, when the rotating drum 4 rotates, the magnetic field applied to each MR element of the magnetic sensor 20 configured as described above changes, as described above. In addition, the electrical resistance of each MR element changes and the output waveform can be extracted.
Here, MR elements located on opposite sides of the bridge connection, for example, elements RA and Ra ′, elements RB and Rb ′, elements RA and RA ′, and elements Rb and RB ′ are arranged adjacent to each other. In addition, since they are substantially separated by a distance of λ / 6, elements connected in series, for example, elements RA, RA ′, elements RB, RB ′, elements Ra, Ra ′ The elements Rb and Rb ′ are substantially spaced apart from each other by a distance corresponding to [(λ / 2) × odd multiple ± λ / 6], and as a result, described with reference to FIG. As described above, the third harmonics included in the output waveform are mutually opposite in phase and can be canceled, and distortion of the output waveform can be suppressed. FIG. 13A is a composite wave of the waveform shown in FIG. 13B and the waveform shown in FIG. This is the same as the case described with reference to FIG.
[0019]
Further, in the conventional magnetic sensor, as shown in FIGS. 9 and 14, the length of the arrangement portion of the MR elements corresponded to a distance of about 2λ, but in this embodiment, the plus side MR elements RA, RB, By arranging Ra and Rb and minus side MR elements Ra ′, Rb ′, RA ′, and RB ′ in a comb shape so as to be adjacent to each other, the length of the arrangement part of the MR elements is shortened, and the multipolar magnetic pattern 8 within a distance corresponding to a length λ of 1 pitch. Specifically, the distance between the MR elements RA and RB ′ at both ends is (11/12) λ.
[0020]
Accordingly, as shown in FIG. 12, the length L of the MR element array portion of the magnetic sensor is approximately halved, so that the distance g1 between the sensor center and the rotating drum 4 and the sensor peripheral portion and the rotating drum 4 are as follows. Since the difference with the distance g2 between the sensor and the gap, that is, the gap difference can be greatly reduced compared to the conventional sensor, the difference in the magnetic flux intensity between the sensor center and the peripheral part is accordingly increased. The amount can be suppressed, and the distortion of the output waveform can be further reduced.
FIG. 2 is a signal waveform showing the A-phase signal and the B-phase signal of the magnetic sensor configured as described above, and an output signal substantially similar to a sine wave could be obtained. When the Lissajous waveform was formed by applying the A-phase signal and the B-phase signal to the X-axis and Y-axis of the oscilloscope, it was possible to obtain a waveform close to a perfect circle as shown in FIG. When the distortion factor of this waveform was measured, the distortion factor was about 1.1%, which was a significant improvement over the conventional sensor distortion factor of 7%.
[0021]
The arrangement of the MR elements shown in FIG. 1 is such that the four MR elements Ra ′, Rb ′, RA ′, RB ′ on the right side shown in FIG. 9 or FIG. 14 are simply combed between the other four MR elements in this order. Although the arrangement is inserted like a tooth, the MR element RB ′ in FIG. 1 is shifted to the left by a distance λ of one pitch so that the MR element RB ′ is positioned at the left end as shown in FIG. It may be. In this case, the distance between the MR elements RB ′ and RB at both ends can be made shorter by a distance substantially equivalent to λ / 12 than the case shown in FIG. 1, and the distortion of the output waveform is correspondingly reduced. Further suppression is possible.
[0022]
In each of the embodiments described above, the MR elements are arranged by being substantially displaced by a distance of λ / 6 in order to mainly cancel the third high frequency component. However, the present invention is not limited to this, and the second high frequency is canceled. In this manner, MR elements may be arranged. The arrangement in this case is shown in FIG. 5. Basically, in order to cancel the second high frequency component, MR elements connected in series, for example, elements RA and RA ′, elements RB and RB ′, Since elements Ra and Ra ′ and elements Rb and Rb ′ need to be substantially separated by a distance of λ / 2 × odd multiple, elements RA and RA ′, elements RB and RB ′, elements Ra, Ra ′ and elements Rb, Rb ′ must be completely stacked in the same place. However, since both elements cannot be stacked one above the other, the two elements are separated from each other by a small distance L1. Are arranged at substantially the same position. The minute interval L1 is preferably as small as possible while maintaining the insulation state between the MR elements, and depends on the thin film forming technique of the MR element. At present, the minute interval L1 is about 5 μm.
[0023]
Furthermore, in the above embodiment, the MR element arrangement in the case of canceling the second high frequency component and the third high frequency component has been described, but one MR element RA, RB is not considered without considering the pitch between adjacent MR elements. , Ra and Rb, the other MR elements Ra ′, Rb ′, RA ′, and RB ′ may be arranged so as to be simply inserted in a comb shape, thereby shortening the overall length of the sensor. In this case, the second or third high-frequency component cannot be canceled, but the higher-order waveform component contained in the output waveform is reduced by shortening the total length of the sensor, and in this case, distortion is also suppressed. Can do.
In addition, by arranging the MR elements in a comb shape, the peak value of the output waveform is slightly reduced, but the amount of reduction is at most about 20%, and the advantage of the distortion suppression effect is much greater. is there.
[0024]
【The invention's effect】
As described above, according to the magnetic sensor of the present invention, the following excellent operational effects can be exhibited.
The plus side magnetoresistive effect element and the minus side magnetoresistive effect element are alternately arranged so as to be adjacent to each other, so that they are arranged in a comb-like shape. Can be as short as possible.
Therefore, the difference in the distance (gap) between the sensor and the circular rotating drum in the element arrangement direction of the sensor is reduced, and as a result, the higher-order harmonic component contained in the output waveform is suppressed and the output waveform is reduced. Distortion can be greatly suppressed.
In particular, the third harmonic component can be canceled by setting the distance between the magnetoresistive effect elements connected in series in the bridge circuit to a distance of substantially λ / 2 × odd multiple ± λ / 6. The distortion of the output waveform can be further suppressed.
Also, by setting the distance between magnetoresistive elements connected in series in the bridge circuit to a distance that is an odd multiple of λ / 2, the second harmonic component can be canceled and distortion of the output waveform is suppressed. can do.
[Brief description of the drawings]
FIG. 1 is a diagram showing an arrangement state of magnetoresistive elements of a magnetic sensor according to the present invention.
FIG. 2 is a waveform diagram showing an A phase signal and a B phase signal obtained from the sensor shown in FIG.
3 is a Lissajous waveform diagram of an A phase signal and a B phase signal shown in FIG.
4 is a view showing a modification of the magnetic sensor shown in FIG. 1. FIG.
FIG. 5 is a view showing another modification of the magnetic sensor of the present invention.
FIG. 6 is a perspective view showing a general magnetic encoder including a magnetic sensor.
7 is a development view showing a multipolar magnetic pattern of the rotating drum shown in FIG. 6. FIG.
FIG. 8 is an explanatory diagram for explaining the principle of operation of the magnetic sensor.
FIG. 9 is a diagram showing a conventional arrangement pattern of magnetoresistive elements of a magnetic sensor.
10 is a circuit diagram showing a connection state of the magnetoresistive effect element shown in FIG. 9;
FIG. 11 is a waveform diagram showing an A-phase signal and a B-phase signal obtained from an ideal magnetic sensor.
FIG. 12 is a partially enlarged view showing the positional relationship between the magnetic sensor and the rotating drum.
FIG. 13 is a waveform diagram for explaining distortion of the output waveform of the magnetoresistive element.
FIG. 14 is a diagram showing another conventional arrangement pattern of magnetoresistive effect elements of a magnetic sensor.
FIG. 15 is a Lissajous waveform diagram of the A phase signal and the B phase signal of the conventional device.
[Explanation of symbols]
2 Rotating shaft 4 Rotating drum 8 Multipolar magnetic pattern 10 Detecting DC power supply 12 A phase side amplifier 14 B phase side amplifier 16 Fundamental wave 18 3rd harmonic 20 Magnetic sensors RA, RB, Ra, Rb Plus side magnetoresistive element RA ', RB', Ra ', Rb' Negative side magnetoresistive element λ Pitch of multipolar magnetic pattern

Claims (7)

A magnetic sensor disposed opposite to a rotating drum having a multipolar magnetic pattern in which N and S poles are magnetized at a predetermined pitch λ, and a plurality of plus side magnets connected to the plus side of a detection DC power source In a magnetic sensor in which a resistance effect element and a plurality of minus side magnetoresistance effect elements connected to the minus side of the detection DC power source are arranged at a specific pitch along the rotation direction of the rotary drum,
The plus side magnetoresistive effect element and the minus side magnetoresistive effect element are alternately arranged adjacent to each other , and the plus side magnetoresistive effect element and the minus side magnetoresistive effect element are used for the A phase and the B phase. And the interval between the A-phase magnetoresistive effect element and the B-phase magnetoresistive effect element is set to an odd multiple of λ / 4. Four magnetoresistive elements of each phase for the phase are connected to each other in a differential manner in the form of a bridge for each phase, and the distance between the magnetoresistive elements connected in series of the bridge is determined as a harmonic component. A magnetic sensor configured to be set to a distance to be canceled . The distance to cancel the harmonic components, the distance der to cancel the third harmonic component is, the distance to cancel the third harmonic component is, distance substantially lambda / 2 × odd multiple ± lambda / 6 the magnetic sensor according to claim 1, characterized in that. The magnetic sensor according to claim 1 or 2, wherein the distance between the magnetoresistive element is connected to a position where the opposite sides of the bridge is the distance substantially lambda / 6. The distance to cancel the harmonic components, the magnetic sensor according to claim 1, wherein the substantially lambda / 2 of the distance of an odd multiple so as to cancel the second harmonic component. The distance between the magnetoresistive element is connected to a position where the opposite sides of the bridge, the magnetic sensor according to claim 1 or 4, wherein it is a small gap such that substantially the same location.   The arrangement of the magnetoresistive effect elements includes two magnetoresistive effect elements on one opposing side of the A-phase bridge, two magnetoresistive effect elements on one opposing side of the B-phase bridge, and the A 2. The two magnetoresistive elements on the other opposite side of the phase bridge and the two magnetoresistive elements on the other opposite side of the B phase bridge are arranged in this order. Or the magnetic sensor of 2.   The arrangement of the magnetoresistive effect elements includes one magnetoresistive effect element in one opposing side of the B-phase bridge, two magnetoresistive effect elements on one opposing side of the A-phase bridge, Two magnetoresistive elements on the other opposite side of the B-phase bridge, two magnetoresistive elements on the other opposite side of the A-phase bridge, and the one opposite side of the B-phase bridge 3. The magnetic sensor according to claim 1, wherein the other magnetoresistive effect elements are arranged in the order.

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