CN111947693B - Magnetic sensor device - Google Patents

Abstract

The invention provides a magnetic sensor device, which is provided with a magnetic grid ruler and a magnetic sensor and can restrain the reduction of detection precision even if a magnetic field is applied from the outside. In the magnetic sensor device, the longitudinal direction of the conductors of the magnetoresistive patterns (27 a-27 d, 28 a-28 d) constituting the + a-phase magnetoresistive pattern (11), the longitudinal direction of the conductors of the magnetoresistive patterns (29 a-29 d, 30 a-30 d) constituting the-a-phase magnetoresistive pattern (12), the longitudinal direction of the conductors of the magnetoresistive patterns (31 a-31 d, 32 a-32 d) constituting the + b-phase magnetoresistive pattern (13), and the longitudinal direction of the conductors of the magnetoresistive patterns (33 a-33 d, 34 a-34 d) constituting the-b-phase magnetoresistive pattern (14) are changed by predetermined angles in a constant direction.

Description

Magnetic sensor device

Technical Field

The present invention relates to a magnetic sensor device including a magnetic scale and a magnetic sensor that moves relative to the magnetic scale.

Background

Conventionally, a rotary encoder including an annular magnetic scale and a detector for detecting a rotational movement of the magnetic scale is known (for example, see patent document 1). In the rotary encoder described in patent document 1, the magnetic scale includes an annular first track disposed radially outside the magnetic scale and an annular second track adjacent to the first track radially inside the magnetic scale. In the first track and the second track, the N pole and the S pole are alternately arranged along the circumferential direction of the magnetic scale with the same width. In the first track and the second track, the positions of the N pole and the S pole are shifted by one magnetic pole in the circumferential direction. Therefore, a rotating magnetic field is generated at a predetermined position of the magnetic scale.

In the rotary encoder described in patent document 1, the detector includes a magnetic sensor substrate on which a magnetoresistive element is mounted. The magnetoresistive element includes an A-phase magnetoresistive pattern and a B-phase magnetoresistive pattern having a phase difference of 90 DEG therebetween. The A-phase magnetoresistive pattern includes a + a-phase magnetoresistive pattern and a-phase magnetoresistive pattern for detecting movement of a magnetic scale with a phase difference of 180 degrees. The B-phase magnetoresistive pattern includes a + B-phase magnetoresistive pattern and a-B-phase magnetoresistive pattern for detecting movement of the magnetic scale with a phase difference of 180 degrees. The + a phase magnetoresistive pattern is formed of a plurality of linear conductors having a longitudinal direction in the radial direction of the magnetic scale. Similarly, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern are each formed of a plurality of linear conductors having a longitudinal direction in the radial direction of the magnetic scale.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2012-118000

Disclosure of Invention

Technical problem to be solved by the invention

As has been clarified by the research of the inventors of the present application, in the rotary encoder described in patent document 1, when a magnetic field is applied to the rotary encoder from the outside, and the external magnetic field (external magnetic field) is combined with the magnetic field generated by the magnetic scale, the detection accuracy of the rotary encoder is lowered. Specifically, as a result of studies by the present inventors, it has been found that in the rotary encoder described in patent document 1, the + a-phase magnetoresistive pattern, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern are each formed by a plurality of linear conductors having a longitudinal direction in the radial direction of the magnetic scale, and when an external magnetic field is applied to the rotary encoder, the influence of the external magnetic field acts on each of the plurality of conductors in the same direction, and the influence of the external magnetic field is amplified, so that the detection accuracy of the rotary encoder is lowered.

Accordingly, an object of the present invention is to provide a magnetic sensor device including a magnetic scale and a magnetic sensor, which can suppress a decrease in detection accuracy even when a magnetic field is applied from the outside.

Technical scheme for solving technical problem

In order to solve the above-described problems, a magnetic sensor device according to the present invention includes a magnetic scale which is formed in an annular shape, a circular shape, or a linear shape, and a magnetic sensor which is disposed so as to face the magnetic scale, wherein the magnetic sensor is relatively moved in a circumferential direction of the magnetic scale with respect to the magnetic scale when the magnetic scale is formed in an annular shape or a circular shape, wherein the magnetic sensor is relatively moved in a longitudinal direction of the magnetic scale with respect to the magnetic scale when the magnetic scale is formed in a linear shape, wherein the magnetic scale includes a plurality of magnetic tracks, wherein N poles and S poles of the plurality of magnetic tracks are alternately arranged with the same width in a relative movement direction of the magnetic sensor with respect to the magnetic scale, wherein the plurality of magnetic tracks are disposed adjacent to each other in a direction orthogonal to the relative movement direction, and wherein the positions of the N poles and the S poles are shifted by one magnetic pole in the relative movement direction, a rotating magnetic field is generated at a predetermined position of a track in an orthogonal direction, in which a direction of a magnetic vector in an in-plane direction parallel to an opposing surface of a magnetic scale opposing a magnetic sensor changes in a direction of relative movement, the magnetic sensor includes an a-phase magnetoresistive pattern and a B-phase magnetoresistive pattern having a phase difference of 90 ° therebetween, the a-phase magnetoresistive pattern includes a + a-phase magnetoresistive pattern and a-phase magnetoresistive pattern for detecting relative movement of the magnetic sensor with respect to the magnetic scale with a phase difference of 180 °, the B-phase magnetoresistive pattern includes a + B-phase magnetoresistive pattern and a-B-phase magnetoresistive pattern for detecting relative movement of the magnetic sensor with respect to the magnetic scale with a phase difference of 180 °, the + a-phase magnetoresistive pattern includes a power source side + a-phase magnetoresistive pattern disposed at a position closer to the power source side than a midpoint position of the + a-phase magnetoresistive pattern, and a ground side + a-phase magnetoresistive pattern disposed at a position closer to the ground side than the midpoint position of the + a-phase magnetoresistive pattern A-phase magnetoresistive pattern including a power source-a-phase magnetoresistive pattern disposed on the power source side of a midpoint position of the-a-phase magnetoresistive pattern and a ground-a-phase magnetoresistive pattern disposed on the ground side of the midpoint position of the-a-phase magnetoresistive pattern, a + b-phase magnetoresistive pattern including a power source-b-phase magnetoresistive pattern disposed on the power source side of the midpoint position of the + b-phase magnetoresistive pattern and a ground-b-phase magnetoresistive pattern disposed on the ground side of the midpoint position of the + b-phase magnetoresistive pattern, a-b-phase magnetoresistive pattern including a power source-b-phase magnetoresistive pattern disposed on the power source side of the midpoint position of the-b-phase magnetoresistive pattern and a ground-b-phase magnetoresistive pattern disposed on the ground side of the midpoint position of the-b-phase magnetoresistive pattern, a power supply side + a phase magnetoresistive pattern, a ground side + a phase magnetoresistive pattern, a power supply side-a phase magnetoresistive pattern, a ground side-a phase magnetoresistive pattern, a power supply side + b phase magnetoresistive pattern, a ground side + b phase magnetoresistive pattern, a power supply side-b phase magnetoresistive pattern, and a ground side-b phase magnetoresistive pattern, which are arranged at positions generating a rotating magnetic field in the orthogonal direction, the power supply side + a phase magnetoresistive pattern being formed of a plurality of block-shaped first magnetoresistive patterns blocked in the relative movement direction, the ground side + a phase magnetoresistive pattern being formed of a plurality of block-shaped second magnetoresistive patterns blocked in the relative movement direction, the power supply side-a phase magnetoresistive pattern being formed of a plurality of block-shaped third magnetoresistive patterns blocked in the relative movement direction, the ground side-a phase magnetoresistive pattern being formed of a plurality of block-shaped fourth magnetoresistive patterns blocked in the relative movement direction, the power supply side + b phase magnetoresistive pattern is composed of a plurality of block-shaped fifth magnetoresistive patterns partitioned in the relative movement direction, the ground side + b phase magnetoresistive pattern is composed of a plurality of block-shaped sixth magnetoresistive patterns partitioned in the relative movement direction, the power supply side-b phase magnetoresistive pattern is composed of a plurality of block-shaped seventh magnetoresistive patterns partitioned in the relative movement direction, the ground side-b phase magnetoresistive pattern is composed of a plurality of block-shaped eighth magnetoresistive patterns partitioned in the relative movement direction, each of the first magnetoresistive pattern, the second magnetoresistive pattern, the third magnetoresistive pattern, the fourth magnetoresistive pattern, the fifth magnetoresistive pattern, the sixth magnetoresistive pattern, the seventh magnetoresistive pattern and the eighth magnetoresistive pattern is formed by folding back a plurality of times a linear conductor whose length direction is a predetermined direction, and the first magnetoresistive patterns, the second magnetoresistive patterns, the third magnetoresistive patterns, the seventh magnetoresistive patterns and the eighth magnetoresistive patterns are formed by folding back a plurality of times a linear conductor whose length direction is a predetermined direction, and the first magnetoresistive patterns, the second magnetoresistive patterns, the third magnetoresistive patterns, the sixth magnetoresistive patterns, the seventh magnetoresistive patterns and the eighth magnetoresistive patterns are formed by folding back a plurality of linear conductors whose length is a plurality of the first magnetoresistive patterns, In each of the plurality of fourth magnetoresistive patterns, the plurality of fifth magnetoresistive patterns, the plurality of sixth magnetoresistive patterns, the plurality of seventh magnetoresistive patterns, and the plurality of eighth magnetoresistive patterns, if the magnetoresistive pattern disposed on the most one end side in the relative movement direction is set as the one-end-side magnetoresistive pattern, and the magnetoresistive pattern disposed on the most other end side in the relative movement direction is set as the other-end-side magnetoresistive pattern, and when the magnetic scale is formed in an annular or circular shape, a central angle formed by one N pole and one S pole adjacent in the circumferential direction of the magnetic scale with respect to the center of the magnetic scale is set as λ, and when the magnetic scale is formed in a substantially linear shape, a sum of a width of the one N pole and a width of the one S pole in the relative movement direction is set as λ, the plurality of first magnetoresistive patterns, the plurality of second magnetoresistive patterns, the plurality of third magnetoresistive patterns, the plurality of fourth magnetoresistive patterns, the plurality of seventh magnetoresistive patterns, and the plurality of eighth magnetoresistive patterns, The plurality of fifth magnetoresistive patterns, the plurality of sixth magnetoresistive patterns, the plurality of seventh magnetoresistive patterns, and the plurality of eighth magnetoresistive patterns are each arranged in a range of λ/2 in the direction of relative movement, and the longitudinal direction of the conductor of each of the plurality of first magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of second magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of third magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of fourth magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of fifth magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of sixth magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of seventh magnetoresistive patterns, and the longitudinal direction of the conductor of each of the plurality of eighth magnetoresistive patterns are each changed by a predetermined angle in a constant direction from one-end magnetoresistive pattern toward the other-end magnetoresistive pattern.

In the magnetic sensor device of the present invention, the longitudinal direction of the conductor of each of the plurality of first magnetoresistive patterns constituting the power source side + a phase magnetoresistive pattern changes by a predetermined angle from one end side magnetoresistive pattern toward the other end side magnetoresistive pattern in a constant direction. Therefore, in the present invention, when an external magnetic field is applied to the magnetic sensor device, the influence of the external magnetic field acts on each of the plurality of first magnetoresistive patterns in different directions. Therefore, in the present invention, when an external magnetic field is applied to the magnetic sensor device, the influence of the external magnetic field acting on each of the plurality of first magnetoresistive patterns can be cancelled out. That is, in the present invention, the influence of the external magnetic field can be canceled out in the power supply side + a phase magnetoresistive pattern, and as a result, the influence of the external magnetic field acting on the power supply side + a phase magnetoresistive pattern can be reduced.

Also, in the present invention, since the longitudinal direction of the conductor of each of the plurality of second magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of third magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of fourth magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of fifth magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of sixth magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of seventh magnetoresistive patterns, and the longitudinal direction of the conductor of each of the plurality of eighth magnetoresistive patterns change by a predetermined angle in a constant direction from the one-end-side magnetoresistive pattern toward the other-end-side magnetoresistive pattern, when an external magnetic field is applied to the magnetic sensor device, at each of the ground-side + a-phase magnetoresistive pattern, the power-side-a-phase magnetoresistive pattern, the ground-side-a-phase magnetoresistive pattern, the power-side + b-phase magnetoresistive pattern, the ground-side + b-phase magnetoresistive pattern, the power-side-b-phase magnetoresistive pattern, and the ground-side-b-phase magnetoresistive pattern, the influence of the external magnetic field can be cancelled out, as a result of which the influence of the external magnetic field acting on each of the ground side + a phase magnetoresistive pattern, the power side-a phase magnetoresistive pattern, the ground side-a phase magnetoresistive pattern, the power side + b phase magnetoresistive pattern, the ground side + b phase magnetoresistive pattern, the power side-b phase magnetoresistive pattern, and the ground side-b phase magnetoresistive pattern can be reduced.

In this way, in the present invention, when an external magnetic field is applied to the magnetic sensor device, the influence of the external magnetic field acting on the power supply side + a phase magnetoresistive pattern, the ground side + a phase magnetoresistive pattern, the power supply side-a phase magnetoresistive pattern, the ground side-a phase magnetoresistive pattern, the power supply side + b phase magnetoresistive pattern, the ground side + b phase magnetoresistive pattern, the power supply side-b phase magnetoresistive pattern, and the ground side-b phase magnetoresistive pattern can be reduced, and therefore, even if a magnetic field is applied to the magnetic sensor device from the outside, the reduction in the detection accuracy of the magnetic sensor device can be suppressed.

In the present invention, the power supply side + a phase magnetoresistive pattern, the ground side + a phase magnetoresistive pattern, the power supply side-a phase magnetoresistive pattern, the ground side-a phase magnetoresistive pattern, the power supply side + b phase magnetoresistive pattern, the ground side + b phase magnetoresistive pattern, the power supply side-b phase magnetoresistive pattern, and the ground side-b phase magnetoresistive pattern are arranged at positions generating a rotating magnetic field in the orthogonal direction, so that even if the longitudinal direction of the conductor of each of the plurality of first magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of second magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of third magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of fourth magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of fifth magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of sixth magnetoresistive patterns, the longitudinal direction of the conductor of each of the plurality of seventh magnetoresistive patterns, and the longitudinal direction of the conductor of each of the plurality of eighth magnetoresistive patterns are oriented from one end side toward one end side The magnetoresistive patterns on the other end side are changed by predetermined angles in the constant direction, and the decrease in the output of the magnetic sensor can be suppressed.

In the present invention, it is preferable that if n is an integer of 2 or more, the power supply side + a phase magnetoresistive pattern is composed of n first magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction, the ground side + a phase magnetoresistive pattern is composed of n second magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction, the power supply side-a phase magnetoresistive pattern is composed of n third magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction, the ground side-a phase magnetoresistive pattern is composed of n fourth magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction, the power supply side + b phase magnetoresistive pattern is composed of n fifth magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction, the ground side + b phase magnetoresistive pattern is composed of n sixth magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction, the power supply side-b phase magnetoresistive pattern is composed of n seventh magnetoresistive patterns arranged at a distance of lambda/2 n in the direction of relative movement, the ground side-b phase magnetoresistive pattern is composed of n eighth magnetoresistive patterns arranged at a distance of lambda/2 n in the direction of relative movement, the longitudinal direction of the conductor of each of the n first magnetoresistive patterns, the longitudinal direction of the conductor of each of the n second magnetoresistive patterns, the longitudinal direction of the conductor of each of the n third magnetoresistive patterns, and the longitudinal direction of the conductor of each of the n fourth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n fifth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n sixth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n seventh magnetoresistive patterns, and the longitudinal direction of the conductor of each of the n eighth magnetoresistive patterns are changed by 180/n ° from one-end magnetoresistive pattern toward the other-end magnetoresistive pattern.

With this configuration, the longitudinal direction of the conductor of each of the n first magnetoresistive patterns arranged within the range of λ/2 in the relative movement direction changes by 180/n ° from one end side magnetoresistive pattern to the other end side magnetoresistive pattern, so that when an external magnetic field is applied to the magnetic sensor device, the influence of the external magnetic field acting on each of the n first magnetoresistive patterns can be effectively cancelled out. That is, the influence of the external magnetic field can be effectively canceled in the power supply side + a phase magnetoresistive pattern, with the result that the influence of the external magnetic field acting on the power supply side + a phase magnetoresistive pattern can be effectively reduced.

In addition, with this configuration, since the longitudinal direction of the conductor of each of the n second magnetoresistive patterns, the longitudinal direction of the conductor of each of the n third magnetoresistive patterns, the longitudinal direction of the conductor of each of the n fourth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n fifth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n sixth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n seventh magnetoresistive patterns, and the longitudinal direction of the conductor of each of the n eighth magnetoresistive patterns, which are arranged within the range of λ/2 in the relative movement direction, are changed by 180/n ° from each of the magnetoresistive patterns on the one end side toward the magnetoresistive patterns on the other end side, similarly, the magnetoresistive patterns on the + a phase on the ground side, the magnetoresistive patterns on the-a phase on the power side, the magnetoresistive patterns on the-a phase on the ground side, the magnetoresistive patterns on the + b phase on the power side, the ground-b phase, and the magnetoresistive patterns on the ground side, The influence of the external magnetic field can be effectively canceled in each of the power supply side-b phase magnetoresistive pattern and the ground side-b phase magnetoresistive pattern, with the result that the influence of the external magnetic field acting on each of the ground side + a phase magnetoresistive pattern, the power supply side-a phase magnetoresistive pattern, the ground side-a phase magnetoresistive pattern, the power supply side + b phase magnetoresistive pattern, the ground side + b phase magnetoresistive pattern, the power supply side-b phase magnetoresistive pattern, and the ground side-b phase magnetoresistive pattern can be effectively reduced. Therefore, even if a magnetic field is applied to the magnetic sensor device from the outside, the decrease in detection accuracy of the magnetic sensor device can be effectively suppressed.

In addition, with this configuration, the longitudinal direction of the conductor of each of the n first magnetoresistive patterns, the longitudinal direction of the conductor of each of the n second magnetoresistive patterns, the longitudinal direction of the conductor of each of the n third magnetoresistive patterns, the longitudinal direction of the conductor of each of the n fourth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n fifth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n sixth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n seventh magnetoresistive patterns, and the longitudinal direction of the conductor of each of the n eighth magnetoresistive patterns, which are arranged at positions where the rotating magnetic field is generated in the orthogonal direction and which are arranged within a range of λ/2 in the relative movement direction, are changed by 180/n ° from the magnetoresistive pattern on the one end side toward the magnetoresistive pattern on the other end, respectively, so that the output of the magnetic sensor can be prevented from being lowered.

In the present invention, it is desirable that the power supply side + a phase magnetoresistive pattern is constituted by four first magnetoresistive patterns arranged at a distance of λ/8 in the direction of relative movement, the ground side + a phase magnetoresistive pattern is constituted by four second magnetoresistive patterns arranged at a distance of λ/8 in the direction of relative movement, the power supply side-a phase magnetoresistive pattern is constituted by four third magnetoresistive patterns arranged at a distance of λ/8 in the direction of relative movement, the ground side-a phase magnetoresistive pattern is constituted by four fourth magnetoresistive patterns arranged at a distance of λ/8 in the direction of relative movement, the power supply side + b phase magnetoresistive pattern is constituted by four fifth magnetoresistive patterns arranged at a distance of λ/8 in the direction of relative movement, the ground side + b phase magnetoresistive pattern is constituted by four sixth magnetoresistive patterns arranged at a distance of λ/8 in the direction of relative movement, the power-side-b-phase magnetoresistive pattern is composed of four seventh magnetoresistive patterns arranged at a λ/8 pitch in the direction of relative movement, the ground-side-b-phase magnetoresistive pattern is composed of four eighth magnetoresistive patterns arranged at a λ/8 pitch in the direction of relative movement, the longitudinal direction of the conductor of each of the four first magnetoresistive patterns, the longitudinal direction of the conductor of each of the four second magnetoresistive patterns, the longitudinal direction of the conductor of each of the four third magnetoresistive patterns, the longitudinal direction of the conductor of each of the four fourth magnetoresistive patterns, the longitudinal direction of the conductor of each of the four fifth magnetoresistive patterns, the longitudinal direction of the conductor of each of the four sixth magnetoresistive patterns, the longitudinal direction of the conductor of each of the four seventh magnetoresistive patterns, and the longitudinal direction of the conductor of each of the four eighth magnetoresistive patterns are changed by 45 ° from the one-end magnetoresistive pattern toward the other-end magnetoresistive pattern.

According to the studies of the inventors of the present application, if the configuration is such that the influence of the external magnetic field can be more effectively canceled in each of the power supply side + a phase magnetoresistive pattern, the ground side + a phase magnetoresistive pattern, the power supply side-a phase magnetoresistive pattern, the ground side-a phase magnetoresistive pattern, the power supply side + b phase magnetoresistive pattern, the ground side + b phase magnetoresistive pattern, the power supply side-b phase magnetoresistive pattern, and the ground side-b phase magnetoresistive pattern, as a result, the influence of the external magnetic field acting on each of the power supply side + a phase magnetoresistive pattern, the ground side + a phase magnetoresistive pattern, the power supply side-a phase magnetoresistive pattern, the ground side-a phase magnetoresistive pattern, the power supply side + b phase magnetoresistive pattern, the ground side + b phase magnetoresistive pattern, the power supply side-b phase magnetoresistive pattern, and the ground side-b phase magnetoresistive pattern can be reduced more effectively.

In the present invention, for example, the first, second, third, fourth, fifth, sixth, seventh, and eighth magnetoresistance patterns are each formed to include a circular region having a diameter defined by λ/2 n.

In the present invention, it is preferable that the plurality of first magnetoresistive patterns are connected in series, the plurality of second magnetoresistive patterns are connected in series, the plurality of third magnetoresistive patterns are connected in series, the plurality of fourth magnetoresistive patterns are connected in series, the plurality of fifth magnetoresistive patterns are connected in series, the plurality of sixth magnetoresistive patterns are connected in series, the plurality of seventh magnetoresistive patterns are connected in series, and the plurality of eighth magnetoresistive patterns are connected in series.

With this configuration, the resistance values of the power supply side + a phase magnetoresistive pattern, the ground side + a phase magnetoresistive pattern, the power supply side-a phase magnetoresistive pattern, the ground side-a phase magnetoresistive pattern, the power supply side + b phase magnetoresistive pattern, the ground side + b phase magnetoresistive pattern, the power supply side-b phase magnetoresistive pattern, and the ground side-b phase magnetoresistive pattern can be increased, and the current values of these magnetoresistive patterns can be reduced. Therefore, power consumption of the magnetic sensor can be reduced.

In the present invention, it is preferable that the magnetic sensor includes a first magnetoresistance pattern layer in which two magnetoresistance patterns selected from a + a-phase magnetoresistance pattern, an-a-phase magnetoresistance pattern, a + b-phase magnetoresistance pattern, and a-b-phase magnetoresistance pattern are formed, and a second magnetoresistance pattern layer in which two magnetoresistance patterns other than the two magnetoresistance patterns formed in the first magnetoresistance pattern layer, among the + a-phase magnetoresistance pattern, the-a-phase magnetoresistance pattern, the + b-phase magnetoresistance pattern, and the-b-phase magnetoresistance pattern, are formed, the first magnetoresistance pattern layer and the second magnetoresistance pattern layer being laminated such that the magnetoresistance pattern formed in the first magnetoresistance pattern layer and the magnetoresistance pattern formed in the second magnetoresistance pattern layer overlap each other. With this configuration, the cost of a chip and the cost of a package on which the chip is mounted can be reduced in a balanced manner, the chip being formed with the + a-phase magnetoresistive pattern, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern.

In the present invention, the magnetic sensor may include a common magnetoresistive pattern layer in which a + a-phase magnetoresistive pattern, an-a-phase magnetoresistive pattern, a + b-phase magnetoresistive pattern, and a-b-phase magnetoresistive pattern are formed. In this case, the cost of a chip for forming the + a-phase magnetoresistive pattern, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern can be reduced.

In the present invention, the magnetic sensor may include a first magnetoresistive pattern layer in which a + a-phase magnetoresistive pattern is formed, a second magnetoresistive pattern layer in which a-phase magnetoresistive pattern is formed, a third magnetoresistive pattern layer in which a + b-phase magnetoresistive pattern is formed, and a fourth magnetoresistive pattern layer in which a-b-phase magnetoresistive pattern is formed, and the first magnetoresistive pattern layer, the second magnetoresistive pattern layer, the third magnetoresistive pattern layer, and the fourth magnetoresistive pattern layer may be stacked such that the + a-phase magnetoresistive pattern, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern overlap each other.

In this case, the chip on which the + a-phase magnetoresistive pattern, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern are formed can be miniaturized, and therefore, the cost of the package on which the chip is mounted can be reduced. In this case, since the + a-phase magnetoresistive pattern, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern overlap each other, it is possible to suppress a decrease in detection accuracy of the magnetic sensor device even if the intensity and direction of the external magnetic field applied to the magnetic sensor device vary within the installation range of the magnetic sensor.

In the present invention, for example, the magnetic scale is formed in a circular ring shape or a circular shape, and the plurality of first magnetoresistive patterns, the plurality of second magnetoresistive patterns, the plurality of third magnetoresistive patterns, the plurality of fourth magnetoresistive patterns, the plurality of fifth magnetoresistive patterns, the plurality of sixth magnetoresistive patterns, the plurality of seventh magnetoresistive patterns, and the plurality of eighth magnetoresistive patterns are arranged in an arc shape, respectively. That is, the magnetic sensor device is, for example, a rotary encoder. In this case, even if a magnetic field is applied from the outside to the magnetic sensor device as the rotary encoder, a decrease in detection accuracy of the magnetic sensor device can be suppressed.

In the present invention, for example, the magnetic scale is formed in a linear shape, and the plurality of first magnetoresistive patterns, the plurality of second magnetoresistive patterns, the plurality of third magnetoresistive patterns, the plurality of fourth magnetoresistive patterns, the plurality of fifth magnetoresistive patterns, the plurality of sixth magnetoresistive patterns, the plurality of seventh magnetoresistive patterns, and the plurality of eighth magnetoresistive patterns are arranged in a linear shape, respectively. That is, the magnetic sensor device is, for example, a linear encoder. In this case, even if a magnetic field is applied from the outside to the magnetic sensor device as the linear encoder, a decrease in detection accuracy of the magnetic sensor device can be suppressed.

Effects of the invention

As described above, according to the present invention, in the magnetic sensor device including the magnetic scale and the magnetic sensor, even if a magnetic field is applied to the magnetic sensor device from the outside, it is possible to suppress a decrease in detection accuracy of the magnetic sensor device.

Drawings

Fig. 1 is a schematic diagram for explaining the configuration of a magnetic sensor device according to an embodiment of the present invention.

Fig. 2 is an enlarged view for explaining the structure of the section E in fig. 1.

Fig. 3 is an enlarged view for explaining the structure of the section E in fig. 1.

Fig. 4 is a side view of the magnetic sensor shown in fig. 1.

Fig. 5 is a circuit diagram of the magnetic sensor shown in fig. 4.

Fig. 6 is a diagram for explaining an output signal of the magnetic sensor shown in fig. 4.

Fig. 7 is a diagram for explaining the structure of the MR chip shown in fig. 4.

Fig. 8 is a diagram for explaining the structure of the first magnetoresistance pattern layer shown in fig. 7.

Fig. 9 is a diagram for explaining the structure of the second magnetoresistance pattern layer shown in fig. 7.

Fig. 10(a) is a graph showing a result obtained by a simulation in which an external magnetic field is applied to the magnetic sensor device shown in fig. 1, and fig. 10(B) is a graph showing a result obtained by a simulation in which an external magnetic field is applied to a magnetic sensor device of the related art.

Fig. 11 is a diagram for explaining the structure of an MR chip according to another embodiment of the present invention.

Fig. 12 is a diagram for explaining the structure of an MR chip according to another embodiment of the present invention.

Fig. 13(a) and 13(B) are graphs showing results obtained by a simulation in which an external magnetic field is applied to a magnetic sensor device according to another embodiment of the present invention.

Fig. 14 is a schematic diagram for explaining the configuration of a magnetic sensor according to another embodiment of the present invention.

Fig. 15 is a schematic diagram for explaining the configuration of a magnetic sensor device according to another embodiment of the present invention.

Description of the reference numerals

1 … magnetic sensor device; 2 … magnetic grid ruler; 2a, 2b … tracks; 2c … opposite face; 3 … magnetic sensor; 8 … A phase magnetoresistive pattern; 9 … B phase magnetoresistive pattern; 11 … + a phase magnetoresistive pattern; the midpoint position of the 11c … + a phase magnetoresistive pattern; 12 … -a phase magnetoresistance pattern; 12c … -a phase magnetoresistive pattern midpoint position; 13 … + b phase magnetoresistive pattern; the midpoint position of the 13c … + b phase magnetoresistive pattern; 14 … -b phase magnetoresistive pattern; position of midpoint of phase 14c … -b magnetoresistive pattern; 27 … power supply side + a phase magnetoresistive pattern; 27a … magnetoresistive pattern (first magnetoresistive pattern, one-end-side magnetoresistive pattern); 27b, 27c … magnetoresistive pattern (first magnetoresistive pattern); 27d … magnetoresistive pattern (first magnetoresistive pattern, other-end-side magnetoresistive pattern); 28 … ground side + a phase magnetoresistive pattern; 28a … magnetoresistive pattern (second magnetoresistive pattern, other-end-side magnetoresistive pattern); 28b, 28c … magnetoresistive pattern (second magnetoresistive pattern); 28d … magnetoresistive pattern (second magnetoresistive pattern, one-end-side magnetoresistive pattern); 29 … power supply side-a phase magnetoresistive pattern; 29a … magnetoresistive pattern (third magnetoresistive pattern, other-end-side magnetoresistive pattern); 29b, 29c … magnetoresistive patterns (third magnetoresistive patterns); 29d … magnetoresistive pattern (third magnetoresistive pattern, one-end-side magnetoresistive pattern); 30 … ground side-a phase magnetoresistive pattern; 30a … magnetoresistive pattern (fourth magnetoresistive pattern, one-end-side magnetoresistive pattern); 30b, 30c … magnetoresistive pattern (fourth magnetoresistive pattern); 30d … magnetoresistive pattern (fourth magnetoresistive pattern, other-end-side magnetoresistive pattern); 31 … power supply side + b phase magnetoresistive pattern; 31a … magnetoresistive pattern (fifth magnetoresistive pattern, one-end-side magnetoresistive pattern); 31b, 31c … magnetoresistive pattern (fifth magnetoresistive pattern); 31d … magnetoresistive pattern (fifth magnetoresistive pattern, other-end-side magnetoresistive pattern); 32 … ground side + b-phase magnetoresistive pattern; 32a … magnetoresistive pattern (sixth magnetoresistive pattern, other-end-side magnetoresistive pattern); 32b, 32c … magnetoresistive pattern (sixth magnetoresistive pattern); 32d … magnetoresistive patterns (sixth magnetoresistive pattern, one-end-side magnetoresistive pattern); 33 … power supply side-b phase magnetoresistive pattern; 33a … magnetoresistive pattern (seventh magnetoresistive pattern, other-end-side magnetoresistive pattern); 33b, 33c … magnetoresistive pattern (seventh magnetoresistive pattern); 33d … magnetoresistive patterns (seventh magnetoresistive pattern, one-end-side magnetoresistive pattern); 34 … grounded side-b phase magnetoresistive pattern; 34a … magnetoresistive pattern (eighth magnetoresistive pattern, one-end-side magnetoresistive pattern); 34b, 34c … magnetoresistive pattern (eighth magnetoresistive pattern); 34d … magnetoresistive pattern (eighth magnetoresistive pattern, other-end-side magnetoresistive pattern); 37 … a first magnetoresistance pattern layer; 38 … second magnetoresistance pattern layer; 40 … common magnetoresistive pattern layer; 41 … a first magnetoresistance pattern layer; 42 … second magnetoresistance pattern layer; 43 … a third magnetoresistance pattern layer; 44 … fourth magnetoresistance pattern layer; h1, H2 … rotating magnetic field; RA1, RA2 … circular area.

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings.

(schematic configuration of magnetic sensor device)

Fig. 1 is a schematic diagram for explaining a configuration of a magnetic sensor device 1 according to an embodiment of the present invention.

The magnetic sensor device 1 of the present embodiment is a rotary encoder used by being attached to a motor having a rotor and a stator, for example. The magnetic sensor device 1 includes a magnetic scale 2 and a magnetic sensor 3 disposed opposite to the magnetic scale 2. The magnetic sensor 3 is fixed to a component on the fixed side of the motor such as a motor case. The magnetic grid ruler 2 is fixed on the rotor. When the rotor rotates, the magnetic scale 2 rotates with respect to the magnetic sensor 3. That is, when the rotor rotates, the magnetic sensor 3 moves relative to the magnetic scale 2. Specifically, when the rotor rotates, the magnetic sensor 3 relatively moves with respect to the magnetic scale 2 in the circumferential direction of the magnetic scale 2. That is, when the rotor rotates, the magnetic sensor 3 rotates relative to the magnetic scale 2.

(Structure of magnetic grid ruler)

Fig. 2 and 3 are enlarged views for explaining the structure of the section E in fig. 1.

The magnetic scale 2 is formed in a circular ring shape or a circular shape. The magnetic scale 2 includes a plurality of tracks 2a and 2b, and N poles and S poles of the plurality of tracks 2a and 2b are alternately arranged in the circumferential direction of the magnetic scale 2 with the same width. The magnetic scale 2 of the present embodiment includes two magnetic tracks 2a and 2 b. The magnetic scale 2 includes a permanent magnet formed in an annular or circular shape, and the magnetic tracks 2a and 2b are formed on the surface of the permanent magnet.

The tracks 2a, 2b are formed in an annular shape. Specifically, the magnetic tracks 2a and 2b are formed in an annular shape with the center of the magnetic scale 2 as the center of curvature. The width of a track 2a in the radial direction of the magnetic scale 2 orthogonal to the circumferential direction of the magnetic scale 2 is equal to the width of a track 2b in the radial direction of the magnetic scale 2. The two magnetic tracks 2a and 2b are concentrically arranged and arranged adjacent to each other in the radial direction of the magnetic scale 2. Specifically, the track 2a is disposed radially inward of the magnetic scale 2, and the track 2b is disposed radially outward of the magnetic scale 2.

The outer circumferential surface of the track 2a and the inner circumferential surface of the track 2b are in contact. In the following description, the circumferential direction of the magnetic scale 2 is referred to as "circumferential direction", and the radial direction of the magnetic scale 2 is referred to as "radial direction". The circumferential direction of the present embodiment is a relative movement direction of the magnetic sensor 3 with respect to the magnetic scale 2, and the radial direction is an orthogonal direction orthogonal to the relative movement direction of the magnetic sensor 3 with respect to the magnetic scale 2.

In the tracks 2a, 2b, the positions of the N pole and the S pole are shifted by one magnetic pole in the circumferential direction. That is, in the magnetic scale 2, the N-pole and the S-pole are arranged in a checkerboard pattern. Therefore, in the present embodiment, the rotating magnetic fields H1, H2 are generated at predetermined positions of the tracks 2a, 2b in the radial direction, and the directions of the magnetic vectors (the directions of the arrows in fig. 2, 3) in the in-plane direction parallel to the facing surface 2c of the magnetic scale 2 facing the magnetic sensor 3 change in the circumferential direction in the rotating magnetic fields H1, H2.

Specifically, the rotating magnetic field H1 is generated in the track 2a at a position slightly radially inward of the boundary between the track 2a and the track 2b, and the rotating magnetic field H2 is generated in the track 2b at a position slightly radially outward of the boundary between the track 2a and the track 2 b. As shown in fig. 2 and 3, in the rotating magnetic fields H1 and H2, the direction of the magnetic vector is rotated 180 ° by the circumferential width of one N pole (i.e., the circumferential width of one S pole).

(Structure of magnetic sensor)

Fig. 4 is a side view of the magnetic sensor 3 shown in fig. 1. Fig. 5 is a circuit diagram of the magnetic sensor 3 shown in fig. 4. Fig. 6 is a diagram for explaining an output signal of the magnetic sensor 3 shown in fig. 4. Fig. 7 is a diagram for explaining the structure of the MR chip 5 shown in fig. 4. Fig. 8 is a diagram for explaining the structure of the first magnetoresistance pattern layer 37 shown in fig. 7. Fig. 9 is a diagram for explaining the structure of the second magnetoresistance pattern layer 38 shown in fig. 7.

As shown in fig. 4, the magnetic sensor 3 includes a chip-type magnetoresistive element 5 (hereinafter referred to as an "MR chip 5"), a sensor substrate 6 on which the MR chip 5 is mounted, and a resin sealing member 7 that covers the MR chip 5 mounted on the sensor substrate 6. The magnetic sensor 3 is disposed so that the detection surface 5a of the MR chip 5 faces the facing surface 2c of the magnetic scale 2. The sensor substrate 6 is a rigid substrate formed of, for example, silicon, ceramic, or the like. The MR chip 5 includes a phase a (SIN phase) magnetoresistive pattern 8 and a phase B (COS phase) magnetoresistive pattern 9 having a phase difference of 90 ° (see fig. 5).

The a-phase magnetoresistive pattern 8 includes a + a-phase magnetoresistive pattern 11 and a-phase magnetoresistive pattern 12 for detecting relative movement of the magnetic sensor 3 with respect to the magnetic scale 2 with a phase difference of 180 °. The + a-phase magnetoresistive pattern 11 and the-a-phase magnetoresistive pattern 12 constitute a bridge circuit. The B-phase magnetoresistive pattern 9 includes a + B-phase magnetoresistive pattern 13 and a-B-phase magnetoresistive pattern 14 for detecting relative movement of the magnetic sensor 3 with respect to the magnetic scale 2 with a phase difference of 180 °. The + b-phase magnetoresistive pattern 13 and the-b-phase magnetoresistive pattern 14 constitute a bridge circuit.

One end of the + a-phase magnetoresistive pattern 11 and one end of the-a-phase magnetoresistive pattern 12 are connected to the power supply terminal 17 (see fig. 7), and the other end of the + a-phase magnetoresistive pattern 11 and the other end of the-a-phase magnetoresistive pattern 12 are connected to the ground terminal 18 (see fig. 7). The midpoint position 11c of the + a-phase magnetoresistive pattern 11 is connected to the terminal 19 (see fig. 7). The midpoint position 12c of the-a-phase magnetoresistive pattern 12 is connected to the terminal 20 (see fig. 7).

Similarly, one end of the + b-phase magnetoresistive pattern 13 and one end of the-b-phase magnetoresistive pattern 14 are connected to the power supply terminal 17, and the other end of the + b-phase magnetoresistive pattern 13 and the other end of the-b-phase magnetoresistive pattern 14 are connected to the ground terminal 18. The midpoint position 13c of the + b-phase magnetoresistive pattern 13 is connected to the terminal 21 (see fig. 7). The midpoint position 14c of the b-phase magnetoresistive pattern 14 is connected to the terminal 22 (see fig. 7).

The terminal 19 outputs, for example, an analog SIN + signal that changes as shown in fig. 6, and the terminal 20 outputs, for example, an analog SIN-signal that changes as shown in fig. 6. The SIN + signal and the SIN-signal are input to a differential circuit 23. The differential circuit 23 outputs an SIN signal (sine wave signal, a-phase signal) in an analog form that varies as shown in fig. 6.

The terminal 21 outputs, for example, an analog COS + signal that changes as shown in fig. 6, and the terminal 22 outputs, for example, an analog COS signal that changes as shown in fig. 6. The COS + signal and the COS-signal are input to the differential circuit 24. The differential circuit 24 outputs COS signals (cosine wave signals, B-phase signals) in analog form that vary as shown in fig. 6. In the present embodiment, the rotation speed and the rotation amount of the magnetic scale 2 are detected based on the SIN signal output from the differential circuit 23 and the COS signal output from the differential circuit 24.

The + a-phase magnetoresistive pattern 11 includes a power supply-side + a-phase magnetoresistive pattern 27 disposed on the power supply side of the midpoint position 11c of the + a-phase magnetoresistive pattern 11, and a ground-side + a-phase magnetoresistive pattern 28 disposed on the ground side of the midpoint position 11c of the + a-phase magnetoresistive pattern 11. The-a-phase magnetoresistive pattern 12 is constituted by a power supply side-a-phase magnetoresistive pattern 29 disposed at a position closer to the power supply side than the midpoint position 12c of the-a-phase magnetoresistive pattern 12, and a ground side-a-phase magnetoresistive pattern 30 disposed at a position closer to the ground side than the midpoint position 12c of the-a-phase magnetoresistive pattern 12.

The + b-phase magnetoresistive pattern 13 includes a power source-side + b-phase magnetoresistive pattern 31 disposed on the power source side of the midpoint position 13c of the + b-phase magnetoresistive pattern 13, and a ground-side + b-phase magnetoresistive pattern 32 disposed on the ground side of the midpoint position 13c of the + b-phase magnetoresistive pattern 13. The b-phase magnetoresistive pattern 14 is composed of a power supply-side-b-phase magnetoresistive pattern 33 disposed at a position closer to the power supply side than the midpoint position 14c of the-b-phase magnetoresistive pattern 14, and a ground-side-b-phase magnetoresistive pattern 34 disposed at a position closer to the ground side than the midpoint position 14c of the-b-phase magnetoresistive pattern 14.

The power supply side + a phase magnetoresistive pattern 27 is constituted by a plurality of block-shaped first magnetoresistive patterns 27a to 27d (hereinafter, referred to as "magnetoresistive patterns 27a to 27 d") which are divided in the circumferential direction. Similarly, the ground-side + a-phase magnetoresistive pattern 28 is formed by a plurality of block-shaped second magnetoresistive patterns 28a to 28d (hereinafter, referred to as "magnetoresistive patterns 28a to 28 d") which are segmented in the circumferential direction, the power-side-a-phase magnetoresistive pattern 29 is formed by a plurality of block-shaped third magnetoresistive patterns 29a to 29d (hereinafter, referred to as "magnetoresistive patterns 29a to 29 d") which are segmented in the circumferential direction, and the ground-side-a-phase magnetoresistive pattern 30 is formed by a plurality of block-shaped fourth magnetoresistive patterns 30a to 30d (hereinafter, referred to as "magnetoresistive patterns 30a to 30 d") which are segmented in the circumferential direction.

The power supply side + b phase magnetoresistive pattern 31 is formed of a plurality of block-shaped fifth magnetoresistive patterns 31a to 31d (hereinafter, referred to as "magnetoresistive patterns 31a to 31 d") partitioned in the circumferential direction, the ground side + b phase magnetoresistive pattern 32 is formed of a plurality of block-shaped sixth magnetoresistive patterns 32a to 32d (hereinafter, referred to as "magnetoresistive patterns 32a to 32 d") partitioned in the circumferential direction, the power supply side-b phase magnetoresistive pattern 33 is formed of a plurality of block-shaped seventh magnetoresistive patterns 33a to 33d (hereinafter, referred to as "magnetoresistive patterns 33a to 33 d") partitioned in the circumferential direction, and the ground side-b phase magnetoresistive pattern 34 is formed of a plurality of block-shaped eighth magnetoresistive patterns 34a to 34d (hereinafter, referred to as "magnetoresistive patterns 34a to 34 d") partitioned in the circumferential direction.

In the present embodiment, the power source side + a phase magnetoresistive pattern 27 is constituted by four magnetoresistive patterns 27a to 27 d. The ground-side + a-phase magnetoresistive pattern 28 is formed of four magnetoresistive patterns 28a to 28d, the power-side-a-phase magnetoresistive pattern 29 is formed of four magnetoresistive patterns 29a to 29d, and the ground-side-a-phase magnetoresistive pattern 30 is formed of four magnetoresistive patterns 30a to 30 d. Similarly, the power supply side + b phase magnetoresistive pattern 31 is formed of four magnetoresistive patterns 31a to 31d, the ground side + b phase magnetoresistive pattern 32 is formed of four magnetoresistive patterns 32a to 32d, the power supply side-b phase magnetoresistive pattern 33 is formed of four magnetoresistive patterns 33a to 33d, and the ground side-b phase magnetoresistive pattern 34 is formed of four magnetoresistive patterns 34a to 34 d.

The four magnetoresistive patterns 27a to 27d are connected in series. Specifically, the four magnetoresistive patterns 27a to 27d are connected in series in this order from the power supply side toward the midpoint position 11 c. Similarly, four magnetoresistive patterns 28a to 28d are connected in series, four magnetoresistive patterns 29a to 29d are connected in series, four magnetoresistive patterns 30a to 30d are connected in series, four magnetoresistive patterns 31a to 31d are connected in series, four magnetoresistive patterns 32a to 32d are connected in series, four magnetoresistive patterns 33a to 33d are connected in series, and four magnetoresistive patterns 34a to 34d are connected in series.

Specifically, the four magnetoresistive patterns 28a to 28d are connected in series in this order from the midpoint position 11c toward the ground side. The four magnetoresistive patterns 29a to 29d are connected in series in this order from the power supply side toward the midpoint position 12c, and the four magnetoresistive patterns 30a to 30d are connected in series in this order from the midpoint position 12c toward the ground side. The four magnetoresistive patterns 31a to 31d are connected in series in this order from the power supply side toward the midpoint position 13c, and the four magnetoresistive patterns 32a to 32d are connected in series in this order from the midpoint position 13c toward the ground side. The four magnetoresistive patterns 33a to 33d are connected in series in this order from the power supply side toward the midpoint position 14c, and the four magnetoresistive patterns 34a to 34d are connected in series in this order from the midpoint position 14c toward the ground side.

The MR chip 5 includes a first magnetoresistive pattern layer 37 on which magnetoresistive patterns 27a to 27d, 28a to 28d, 33a to 33d, and 34a to 34d are formed, and a second magnetoresistive pattern layer 38 on which magnetoresistive patterns 29a to 29d, 30a to 30d, 31a to 31d, and 32a to 32d are formed.

That is, the magnetic sensor 3 includes a first magnetoresistive pattern layer 37 and a second magnetoresistive pattern layer 38, the first magnetoresistive pattern layer 37 is provided with the + a-phase magnetoresistive pattern 11, the-a-phase magnetoresistive pattern 12, the + b-phase magnetoresistive pattern 13, and the-b-phase magnetoresistive pattern 14, which are two magnetoresistive patterns among the-a-phase magnetoresistive pattern 11, the-a-phase magnetoresistive pattern 12, the + b-phase magnetoresistive pattern 13, and the-b-phase magnetoresistive pattern 14, and the second magnetoresistive pattern layer 38 is provided with the-a-phase magnetoresistive pattern 12 and the + b-phase magnetoresistive pattern 13, which are magnetoresistive patterns other than the two + a-phase magnetoresistive pattern 11 and the-b-phase magnetoresistive pattern 14 formed in the first magnetoresistive pattern layer 37, which are formed in the + a-phase magnetoresistive pattern 11 and the-b-phase magnetoresistive pattern 14.

The first magnetoresistive pattern layer 37 is formed in a rectangular shape. In the first magnetoresistive pattern layer 37, the four magnetoresistive patterns 27a to 27d, the four magnetoresistive patterns 28a to 28d, the four magnetoresistive patterns 33a to 33d, and the four magnetoresistive patterns 34a to 34d are arranged in an arc shape, respectively. Specifically, the four magnetoresistive patterns 27a to 27d, the four magnetoresistive patterns 28a to 28d, the four magnetoresistive patterns 33a to 33d, and the four magnetoresistive patterns 34a to 34d are arranged in an arc shape with the center of curvature of the magnetic scale 2 as a center.

The magnetoresistive patterns 27a to 27d and the magnetoresistive patterns 33a to 33d are arranged at the same positions in the radial direction. The magnetoresistive patterns 28a to 28d and the magnetoresistive patterns 34a to 34d are arranged at the same positions in the radial direction. In the present embodiment, the magnetoresistive patterns 27a to 27d and 33a to 33d are disposed radially outward of the magnetoresistive patterns 28a to 28d and 34a to 34 d.

In the present embodiment, the power supply terminal 17 and the ground terminal 18 are arranged at the center in the circumferential direction of the MR chip 5, the magnetoresistive patterns 33a to 33d and 34a to 34d are arranged at positions on one side in the circumferential direction (specifically, on the clockwise direction side in fig. 7) with respect to the center in the circumferential direction of the power supply terminal 17 and the ground terminal 18, and the magnetoresistive patterns 27a to 27d and 28a to 28d are arranged at positions on the other side in the circumferential direction (specifically, on the counterclockwise direction side in fig. 7) with respect to the center in the circumferential direction of the power supply terminal 17 and the ground terminal 18. In the following description, the clockwise direction in fig. 7 is referred to as a "clockwise direction", and the counterclockwise direction in fig. 7 is referred to as a "counterclockwise direction".

The second magnetoresistive pattern layer 38 is formed in a rectangular shape having the same shape as the first magnetoresistive pattern layer 37. In the second magnetoresistive pattern layer 38, the four magnetoresistive patterns 29a to 29d, the four magnetoresistive patterns 30a to 30d, the four magnetoresistive patterns 31a to 31d, and the four magnetoresistive patterns 32a to 32d are arranged in an arc shape, respectively. Specifically, the four magnetoresistive patterns 29a to 29d, the four magnetoresistive patterns 30a to 30d, the four magnetoresistive patterns 31a to 31d, and the four magnetoresistive patterns 32a to 32d are arranged in an arc shape with the center of curvature of the magnetic scale 2 as a center.

The magnetoresistive patterns 29a to 29d and the magnetoresistive patterns 31a to 31d are arranged at the same positions in the radial direction. The magnetoresistive patterns 30a to 30d and the magnetoresistive patterns 32a to 32d are arranged at the same positions in the radial direction. In the present embodiment, the magnetoresistive patterns 29a to 29d and 31a to 31d are disposed radially outward of the magnetoresistive patterns 30a to 30d and 32a to 32 d. The magnetoresistive patterns 29a to 29d and 31a to 31d are arranged at the same positions as the magnetoresistive patterns 27a to 27d and 33a to 33d in the radial direction, and the magnetoresistive patterns 30a to 30d and 32a to 32d are arranged at the same positions as the magnetoresistive patterns 28a to 28d and 34a to 34d in the radial direction.

The magnetoresistive patterns 29a to 29d and 30a to 30d are disposed on one side (clockwise side) in the circumferential direction with respect to the centers in the circumferential direction of the power supply terminal 17 and the ground terminal 18, and the magnetoresistive patterns 31a to 31d and 32a to 32d are disposed on the other side (counterclockwise side) in the circumferential direction with respect to the centers in the circumferential direction of the power supply terminal 17 and the ground terminal 18. The power supply terminal 17 is disposed at the outer end of the MR chip 5 in the radial direction, and the ground terminal 18 is disposed at the inner end of the MR chip 5 in the radial direction. The terminals 20 and 21 are disposed at the outer ends in the radial direction of the MR chip 5, and the terminals 19 and 22 are disposed at the inner ends in the radial direction of the MR chip 5. The terminals 20 and 22 are disposed on the clockwise end side of the MR chip 5, and the terminals 19 and 21 are disposed on the counterclockwise end side of the MR chip 5.

The four magnetoresistive patterns 27a to 27d are arranged in this order from one end side to the other end side in the circumferential direction (specifically, in the counterclockwise direction), and the four magnetoresistive patterns 28a to 28d are arranged in this order in the clockwise direction. The four magnetoresistive patterns 29a to 29d are arranged in this order toward the clockwise direction, and the four magnetoresistive patterns 30a to 30d are arranged in this order toward the counterclockwise direction. The four magnetoresistive patterns 31a to 31d are arranged in this order toward the counterclockwise direction, and the four magnetoresistive patterns 32a to 32d are arranged in this order toward the clockwise direction. The four magnetoresistive patterns 33a to 33d are arranged in this order toward the clockwise direction, and the four magnetoresistive patterns 34a to 34d are arranged in this order toward the counterclockwise direction.

The magnetoresistive pattern 27a of the present embodiment is one of the four magnetoresistive patterns 27a to 27d that is disposed closest to one end side in the circumferential direction, which is the direction of relative movement of the magnetic sensor 3 with respect to the magnetic scale 2, and the magnetoresistive pattern 27d is the other one of the four magnetoresistive patterns 27a to 27d that is disposed closest to the other end side in the circumferential direction.

The magnetoresistive pattern 28d of the present embodiment is one of the four magnetoresistive patterns 28a to 28d disposed closest to one end in the circumferential direction, and the magnetoresistive pattern 28a is the other of the four magnetoresistive patterns 28a to 28d disposed closest to the other end in the circumferential direction. Similarly, the magnetoresistive patterns 29d, 30a, 31a, 32d, 33d, and 34a of the present embodiment are one-end-side magnetoresistive patterns, and the magnetoresistive patterns 29a, 30d, 31d, 32a, 33a, and 34d are the other-end-side magnetoresistive patterns.

As shown in fig. 8 and 9, the magnetoresistive patterns 27a to 27d, 28a to 28d, 29a to 29d, 30a to 30d, 31a to 31d, 32a to 32d, 33a to 33d, and 34a to 34d are each formed by folding back a plurality of linear conductors whose longitudinal directions are defined in a predetermined direction. The magnetoresistive patterns 27a to 27d, 28a to 28d, 29a to 29d, 30a to 30d, 31a to 31d, 32a to 32d, 33a to 33d, and 34a to 34d of the present embodiment are formed in rectangular shapes. The magnetoresistive patterns 27a to 27d, 28a to 28d, 29a to 29d, 30a to 30d, 31a to 31d, 32a to 32d, 33a to 33d, and 34a to 34d of the present embodiment are all formed in the same shape.

As shown in fig. 1, if the central angle formed by one N pole and one S pole adjacent to each other in the circumferential direction with respect to the center of the magnetic scale 2 is λ (that is, if the magnitude (angle) of the central angle is λ), the magnetoresistive patterns 27a to 27d, 28a to 28d, 29a to 29d, 30a to 30d, 31a to 31d, 32a to 32d, 33a to 33d, and 34a to 34d are formed so as to respectively fit into circular regions RA1 and RA2 (see fig. 8) having a diameter defined by λ/8.

Specifically, the magnetoresistive patterns 27a to 27d, 29a to 29d, 31a to 31d, and 33a to 33d are formed to respectively fit into the circular region RA1, and the magnetoresistive patterns 28a to 28d, 30a to 30d, 32a to 32d, and 34a to 34d are formed to respectively fit into the circular region RA 2. In the present embodiment, the diameter of the circular region RA1 is 1/8 which is the sum of the circumferential width of one N pole and the circumferential width of one S pole at the positions where the magnetoresistive patterns 27a to 27d, 29a to 29d, 31a to 31d, and 33a to 33d are arranged in the radial direction. The diameter of the circular region RA2 is 1/8 that is the sum of the circumferential width of one N pole and the circumferential width of one S pole at the positions where the magnetoresistive patterns 28a to 28d, 30a to 30d, 32a to 32d, and 34a to 34d are arranged in the radial direction.

As shown in fig. 8, four magnetoresistive patterns 27a to 27d are arranged at λ/8 pitch in the circumferential direction. Similarly, the four magnetoresistive patterns 28a to 28d are arranged at λ/8 pitches in the circumferential direction, the four magnetoresistive patterns 29a to 29d are arranged at λ/8 pitches in the circumferential direction, the four magnetoresistive patterns 30a to 30d are arranged at λ/8 pitches in the circumferential direction, the four magnetoresistive patterns 31a to 31d are arranged at λ/8 pitches in the circumferential direction, the four magnetoresistive patterns 32a to 32d are arranged at λ/8 pitches in the circumferential direction, the four magnetoresistive patterns 33a to 33d are arranged at λ/8 pitches in the circumferential direction, and the four magnetoresistive patterns 34a to 34d are arranged at λ/8 pitches in the circumferential direction.

Therefore, as shown in fig. 2 and 3, the four magnetoresistive patterns 27a to 27d are arranged in the circumferential direction in the range of λ/2, the four magnetoresistive patterns 28a to 28d are arranged in the circumferential direction in the range of λ/2, the four magnetoresistive patterns 29a to 29d are arranged in the circumferential direction in the range of λ/2, the four magnetoresistive patterns 30a to 30d are arranged in the circumferential direction in the range of λ/2, the four magnetoresistive patterns 31a to 31d are arranged in the circumferential direction in the range of λ/2, the four magnetoresistive patterns 32a to 32d are arranged in the circumferential direction in the range of λ/2, the four magnetoresistive patterns 33a to 33d are arranged in the circumferential direction in the range of λ/2, and the four magnetoresistive patterns 34a to 34d are arranged in the circumferential direction in the range of λ/2.

That is, the four magnetoresistive patterns 27a to 27d, the four magnetoresistive patterns 28a to 28d, the four magnetoresistive patterns 29a to 29d, the four magnetoresistive patterns 30a to 30d, the four magnetoresistive patterns 31a to 31d, the four magnetoresistive patterns 32a to 32d, the four magnetoresistive patterns 33a to 33d, and the four magnetoresistive patterns 34a to 34d are each arranged within the range of the circumferential width of one N pole (or the circumferential width of one S pole).

In the MR chip 5, the first magnetoresistance pattern layer 37 and the second magnetoresistance pattern layer 38 are laminated such that the + a-phase magnetoresistance pattern 11 and the-b-phase magnetoresistance pattern 14 formed in the first magnetoresistance pattern layer 37 and the-a-phase magnetoresistance pattern 12 and the + b-phase magnetoresistance pattern 13 formed in the second magnetoresistance pattern layer 38 overlap. That is, the MR chip 5 has a two-layer structure in which the first magnetoresistive pattern layer 37 and the second magnetoresistive pattern layer 38 are stacked.

Specifically, the first magnetoresistive pattern layer 37 and the second magnetoresistive pattern layer 38 are laminated such that each of the magnetoresistive patterns 27a to 27d overlaps each of the magnetoresistive patterns 31a to 31d, each of the magnetoresistive patterns 28a to 28d overlaps each of the magnetoresistive patterns 32a to 32d, each of the magnetoresistive patterns 33a to 33d overlaps each of the magnetoresistive patterns 29a to 29d, and each of the magnetoresistive patterns 34a to 34d overlaps each of the magnetoresistive patterns 30a to 30 d.

The magnetoresistive patterns 28a to 28d, 30a to 30d, 32a to 32d, and 34a to 34d are arranged at positions generating the rotating magnetic field H1 in the radial direction, and the magnetoresistive patterns 27a to 27d, 29a to 29d, 31a to 31d, and 33a to 33d are arranged at positions generating the rotating magnetic field H2 in the radial direction. That is, the ground-side + a-phase magnetoresistive pattern 28, the ground-side-a-phase magnetoresistive pattern 30, the ground-side + b-phase magnetoresistive pattern 32, and the ground-side-b-phase magnetoresistive pattern 34 are arranged at positions in the radial direction where the rotating magnetic field H1 is generated, and the power-side + a-phase magnetoresistive pattern 27, the power-side-a-phase magnetoresistive pattern 29, the power-side + b-phase magnetoresistive pattern 31, and the power-side-b-phase magnetoresistive pattern 33 are arranged at positions in the radial direction where the rotating magnetic field H2 is generated.

The longitudinal direction of the conductor of each of the four magnetoresistive patterns 27a to 27d changes by a predetermined angle in a constant direction from the magnetoresistive pattern 27a toward the magnetoresistive pattern 27 d. Specifically, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 27a to 27d is changed by 45 ° from the magnetoresistive pattern 27a toward the magnetoresistive pattern 27d in the clockwise direction.

Similarly, the longitudinal directions of the conductors of the four magnetoresistive patterns 28a to 28d are changed by predetermined angles in the constant direction from the magnetoresistive pattern 28d toward the magnetoresistive pattern 28a, the longitudinal directions of the conductors of the four magnetoresistive patterns 29a to 29d are changed by predetermined angles in the constant direction from the magnetoresistive pattern 29d toward the magnetoresistive pattern 29a, and the longitudinal directions of the conductors of the four magnetoresistive patterns 30a to 30d are changed by predetermined angles in the constant direction from the magnetoresistive pattern 30a toward the magnetoresistive pattern 30 d.

The longitudinal directions of the conductors of the four magnetoresistive patterns 31a to 31d are changed by predetermined angles in the constant direction from the magnetoresistive pattern 31a to the magnetoresistive pattern 31d, the longitudinal directions of the conductors of the four magnetoresistive patterns 32a to 32d are changed by predetermined angles in the constant direction from the magnetoresistive pattern 32d to the magnetoresistive pattern 32a, the longitudinal directions of the conductors of the four magnetoresistive patterns 33a to 33d are changed by predetermined angles in the constant direction from the magnetoresistive pattern 33d to the magnetoresistive pattern 33a, and the longitudinal directions of the conductors of the four magnetoresistive patterns 34a to 34d are changed by predetermined angles in the constant direction from the magnetoresistive pattern 34a to the magnetoresistive pattern 34 d.

Specifically, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 28a to 28d changes by 45 ° in the counterclockwise direction from the magnetoresistive pattern 28d toward the magnetoresistive pattern 28a, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 29a to 29d changes by 45 ° in the clockwise direction from the magnetoresistive pattern 29d toward the magnetoresistive pattern 29a, and the longitudinal direction of the conductor of each of the four magnetoresistive patterns 30a to 30d changes by 45 ° in the counterclockwise direction from the magnetoresistive pattern 30a toward the magnetoresistive pattern 30 d.

In addition, the longitudinal directions of the conductors of the four magnetoresistive patterns 31a to 31d are changed by 45 ° in the clockwise direction from the magnetoresistive pattern 31a toward the magnetoresistive pattern 31d, the longitudinal directions of the conductors of the four magnetoresistive patterns 32a to 32d are changed by 45 ° in the counterclockwise direction from the magnetoresistive pattern 32d toward the magnetoresistive pattern 32a, the longitudinal directions of the conductors of the four magnetoresistive patterns 33a to 33d are changed by 45 ° in the clockwise direction from the magnetoresistive pattern 33d toward the magnetoresistive pattern 33a, and the longitudinal directions of the conductors of the four magnetoresistive patterns 34a to 34d are changed by 45 ° in the counterclockwise direction from the magnetoresistive pattern 34a toward the magnetoresistive pattern 34 d.

As shown in fig. 2 and 3, in the rotating magnetic field H1, the direction of the magnetic vector rotates counterclockwise as it goes to the counterclockwise side of the magnetic scale 2. In the rotating magnetic field H1, the direction of the magnetic vector changes by 45 ° in the counterclockwise direction within the range of λ/8 as going toward the counterclockwise direction side of the magnetic scale 2. In the rotating magnetic field H2, the direction of the magnetic vector rotates clockwise as it goes to the counterclockwise direction of the magnetic scale 2. In the rotating magnetic field H2, the direction of the magnetic vector changes by 45 ° in the clockwise direction in the range of λ/8 as going toward the counterclockwise direction side of the magnetic scale 2.

In the magnetoresistive patterns 28a to 28d arranged at the positions where the rotating magnetic field H1 is generated in the radial direction, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 28a to 28d rotates in the same direction as the rotating direction of the rotating magnetic field H1 as it goes to the counterclockwise direction side. Similarly, in the magnetoresistive patterns 30a to 30d arranged at the position where the rotating magnetic field H1 is generated in the radial direction, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 30a to 30d rotates in the same direction as the rotating direction of the rotating magnetic field H1 as it goes to the counterclockwise direction side.

Further, in the magnetoresistive patterns 32a to 32d arranged at the position where the rotating magnetic field H1 is generated in the radial direction, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 32a to 32d rotates in the same direction as the rotating direction of the rotating magnetic field H1 as it goes to the counterclockwise side, and in the magnetoresistive patterns 34a to 34d arranged at the position where the rotating magnetic field H1 is generated in the radial direction, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 34a to 34d rotates in the same direction as the rotating direction of the rotating magnetic field H1 as it goes to the counterclockwise side.

In the magnetoresistive patterns 27a to 27d arranged at the position where the rotating magnetic field H2 is generated in the radial direction, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 27a to 27d rotates in the same direction as the rotating direction of the rotating magnetic field H2 as it goes to the counterclockwise direction side. Similarly, in the magnetoresistive patterns 29a to 29d arranged at the position where the rotating magnetic field H2 is generated in the radial direction, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 29a to 29d rotates in the same direction as the rotating direction of the rotating magnetic field H2 as it goes to the counterclockwise direction side.

Further, in the magnetoresistive patterns 31a to 31d arranged in the radial direction at the position where the rotating magnetic field H2 is generated, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 31a to 31d rotates in the same direction as the rotating direction of the rotating magnetic field H2 as it goes to the counterclockwise direction side, and in the magnetoresistive patterns 33a to 33d arranged in the radial direction at the position where the rotating magnetic field H2 is generated, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 33a to 33d rotates in the same direction as the rotating direction of the rotating magnetic field H2 as it goes to the counterclockwise direction side.

That is, in the present embodiment, the magnetoresistive patterns 28a to 28d, 30a to 30d, 32a to 32d, and 34a to 34d, which are arranged at positions where the rotating magnetic field H1 is generated in the radial direction, are arranged at equivalent positions of the rotating magnetic field H1. The magnetoresistive patterns 27a to 27d, 29a to 29d, 31a to 31d, and 33a to 33d, which are disposed at positions where the rotating magnetic field H2 is generated in the radial direction, are disposed at equivalent positions of the rotating magnetic field H2.

In the present embodiment, the longitudinal direction of the conductors of the magnetoresistive patterns 27a and 33a coincides with the circumferential direction, and the longitudinal direction of the conductors of the magnetoresistive patterns 28d and 34d coincides with the radial direction. In addition, the longitudinal directions of the conductors of the magnetoresistive patterns 29a, 30d are inclined by 45 ° in the clockwise direction with respect to the circumferential direction, and the longitudinal directions of the conductors of the magnetoresistive patterns 31a, 32d are inclined by 45 ° in the counterclockwise direction with respect to the circumferential direction.

(main effect of the present embodiment)

As described above, in the present embodiment, the longitudinal direction of the conductor of each of the four magnetoresistive patterns 27a to 27d constituting the power source side + a phase magnetoresistive pattern 27 is changed by a predetermined angle in a constant direction from the magnetoresistive pattern 27a toward the magnetoresistive pattern 27 d. Therefore, in the present embodiment, when an external magnetic field is applied to the magnetic sensor device 1, the influence of the external magnetic field acts on each of the magnetoresistive patterns 27a to 27d in different directions. Therefore, in the present embodiment, when an external magnetic field is applied to the magnetic sensor device 1, the influence of the external magnetic field acting on each of the magnetoresistive patterns 27a to 27d can be cancelled out. That is, in the present embodiment, the influence of the external magnetic field can be canceled out in the power supply side + a phase magnetoresistive pattern 27, and as a result, the influence of the external magnetic field acting on the power supply side + a phase magnetoresistive pattern 27 can be reduced.

Similarly, in the present embodiment, since the longitudinal direction of the conductor of each of the magnetoresistive patterns 28a to 28d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 29a to 29d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 30a to 30d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 31a to 31d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 32a to 32d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 33a to 33d, and the longitudinal direction of the conductor of each of the magnetoresistive patterns 34a to 34d are changed by a predetermined angle in a constant direction, when an external magnetic field is applied to the magnetic sensor device 1, at each of the ground side + a phase magnetoresistive pattern 28, the power side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34, the influence of the external magnetic field can be canceled out, and as a result, the influence of the external magnetic field acting on the ground side + a phase magnetoresistive pattern 28, the power side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34 can be reduced.

As described above, in the present embodiment, when an external magnetic field is applied to the magnetic sensor device 1, the influence of the external magnetic field acting on the power supply side + a phase magnetoresistive pattern 27, the ground side + a phase magnetoresistive pattern 28, the power supply side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power supply side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power supply side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34 can be reduced, and therefore, even if a magnetic field is applied from the outside of the magnetic sensor device 1, the reduction in the detection accuracy of the magnetic sensor device 1 can be suppressed.

In particular, in the present embodiment, since the longitudinal direction of the conductor of each of the four magnetoresistive patterns 27a to 27d arranged within the range of λ/2 in the circumferential direction is changed by 45 ° from the magnetoresistive pattern 27a to the magnetoresistive pattern 27d, when an external magnetic field is applied to the magnetic sensor device 1, the influence of the external magnetic field acting on each of the magnetoresistive patterns 27a to 27d can be effectively cancelled. That is, in the present embodiment, the influence of the external magnetic field can be effectively canceled out in the power supply side + a phase magnetoresistive pattern 27, and as a result, the influence of the external magnetic field acting on the power supply side + a phase magnetoresistive pattern 27 can be effectively reduced.

Similarly, in the present embodiment, since the longitudinal direction of the conductor of each of the magnetoresistive patterns 28a to 28d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 29a to 29d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 30a to 30d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 31a to 31d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 32a to 32d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 33a to 33d, and the longitudinal direction of the conductor of each of the magnetoresistive patterns 34a to 34d are changed by 45 ° in the circumferential direction, it is possible to effectively cancel the external magnetic field in each of the ground-side + a-phase magnetoresistive pattern 28, the power-side-a-phase magnetoresistive pattern 29, the ground-side-a-phase magnetoresistive pattern 30, the power-side + b-phase magnetoresistive pattern 31, the ground-side + b-phase magnetoresistive pattern 32, the power-side-b-phase magnetoresistive pattern 33, and the ground-side-b-phase magnetoresistive pattern 34 As a result, it is possible to effectively cancel the influence of the external magnetic field acting on each of the ground side + a phase magnetoresistive pattern 28, the power side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34. Therefore, in the present embodiment, even if a magnetic field is applied from the outside of the magnetic sensor device 1, it is possible to effectively suppress a decrease in the detection accuracy of the magnetic sensor device 1.

In the present embodiment, the magnetoresistive patterns 28a to 28d, 30a to 30d, 32a to 32d, and 34a to 34d arranged at positions generating the rotating magnetic field H1 in the radial direction are arranged at equivalent positions of the rotating magnetic field H1, and the magnetoresistive patterns 27a to 27d, 29a to 29d, 31a to 31d, and 33a to 33d arranged at positions generating the rotating magnetic field H2 in the radial direction are arranged at equivalent positions of the rotating magnetic field H2.

Therefore, in the present embodiment, even if the longitudinal direction of the conductor of each of the magnetoresistive patterns 27a to 27d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 28a to 28d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 29a to 29d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 30a to 30d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 31a to 31d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 32a to 32d, the longitudinal direction of the conductor of each of the magnetoresistive patterns 33a to 33d, and the longitudinal direction of the conductor of each of the magnetoresistive patterns 34a to 34d are changed by a predetermined angle in each of the constant directions, it is possible to prevent the output of the magnetic sensor 3 from being lowered.

In the present embodiment, the magnetoresistive patterns 27a to 27d are connected in series, the magnetoresistive patterns 28a to 28d are connected in series, the magnetoresistive patterns 29a to 29d are connected in series, the magnetoresistive patterns 30a to 30d are connected in series, the magnetoresistive patterns 31a to 31d are connected in series, the magnetoresistive patterns 32a to 32d are connected in series, the magnetoresistive patterns 33a to 33d are connected in series, and the magnetoresistive patterns 34a to 34d are connected in series.

Therefore, in the present embodiment, it is possible to increase the resistance values of each of the power supply side + a phase magnetoresistive pattern 27, the ground side + a phase magnetoresistive pattern 28, the power supply side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power supply side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power supply side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34, and to reduce the current value of each of these magnetoresistive patterns. Therefore, in the present embodiment, the power consumption of the magnetic sensor 3 can be reduced.

(simulation)

Fig. 10(a) is a graph showing a result obtained by a simulation in which an external magnetic field is applied to the magnetic sensor device 1 shown in fig. 1, and fig. 10(B) is a graph showing a result obtained by a simulation in which an external magnetic field is applied to a magnetic sensor device of the related art.

Simulation was performed to apply an external magnetic field to the magnetic sensor device 1 and the magnetic sensor device of the related art described in patent document 1. In this simulation, the angle when the direction of the external magnetic field is directed to the counterclockwise direction side of the magnetic scale 2 is set to 0 °, and an error of the magnetic sensor device 1 and an error of the magnetic sensor device of the related art, which are generated when the direction of the external magnetic field is rotated 360 ° at a pitch of 22.5 °, are obtained. In the simulation, the diameter of the magnetic scale 2 was set to 20mm, and λ was set to 11.25 °.

In the simulation, the intensity of the magnetic field generated by the magnetic scale 2 was set to 10mT (millitesla), and the intensity of the external magnetic field was set to 3 mT. In fig. 10 a and 10B, numerals arranged in the circumferential direction of the graph indicate the direction (angle) of the external magnetic field. In fig. 10(a) and 10(B), numbers arranged in the radial direction of the graph indicate the magnitude of the generated error. The error generated indicates an angle when one N pole and one S pole are set to 360 °.

Fig. 10(a) shows the simulation result of the magnetic sensor device 1, and fig. 10(B) shows the simulation result of the conventional magnetic sensor device. As shown in fig. 10(a) and 10(B), in the simulation, an error of about 1.7 ° is generated at the maximum in the magnetic sensor device of the related art, but an error of about 0.2 ° is generated at the maximum in the magnetic sensor device 1 of the present embodiment. That is, as is clear from the results of the simulation, in the magnetic sensor device 1 of the present embodiment, even if a magnetic field is applied from the outside of the magnetic sensor device 1, it is possible to significantly suppress a decrease in the detection accuracy of the magnetic sensor device 1 as compared with the magnetic sensor device of the related art.

(modification of MR chip)

Fig. 11 and 12 are diagrams for explaining the structure of the MR chip 5 according to another embodiment of the present invention.

In the above-described embodiment, the MR chip 5 has a two-layer structure in which the first magnetoresistive pattern layer 37 and the second magnetoresistive pattern layer 38 are stacked, but as shown in fig. 11, the MR chip 5 may have a one-layer structure including the common magnetoresistive pattern layer 40 in which the + a-phase magnetoresistive pattern 11, the-a-phase magnetoresistive pattern 12, the + b-phase magnetoresistive pattern 13, and the-b-phase magnetoresistive pattern 14 are formed. In this case, the cost of the MR chip 5 can be reduced. In fig. 11, the same components as those of the above-described embodiment are denoted by the same reference numerals. In the example shown in fig. 11, the-a-phase magnetoresistive pattern 12 and the + b-phase magnetoresistive pattern 13 are adjacent in the circumferential direction, but the + a-phase magnetoresistive pattern 11 and the-b-phase magnetoresistive pattern 14 may be adjacent in the circumferential direction.

In the above-described embodiment, the MR chip 5 may have a four-layer structure including the first magnetoresistance pattern layer 41 having the + a-phase magnetoresistance pattern 11 formed thereon, the second magnetoresistance pattern layer 42 having the-a-phase magnetoresistance pattern formed thereon, the third magnetoresistance pattern layer 43 having the + b-phase magnetoresistance pattern formed thereon, and the fourth magnetoresistance pattern layer 44 having the-b-phase magnetoresistance pattern formed thereon. In this case, as shown in fig. 12, the first magnetoresistance pattern layer 41, the second magnetoresistance pattern layer 42, the third magnetoresistance pattern layer 43, and the fourth magnetoresistance pattern layer 44 are laminated such that the + a-phase magnetoresistance pattern 11, the-a-phase magnetoresistance pattern 12, the + b-phase magnetoresistance pattern 13, and the-b-phase magnetoresistance pattern 14 overlap.

Specifically, the first magnetoresistive pattern layer 41, the second magnetoresistive pattern layer 42, the third magnetoresistive pattern layer 43, and the fourth magnetoresistive pattern layer 44 are laminated such that the power-side + a-phase magnetoresistive pattern 27, the power-side-a-phase magnetoresistive pattern 29, the power-side + b-phase magnetoresistive pattern 31, and the power-side-b-phase magnetoresistive pattern 33 overlap, and the ground-side + a-phase magnetoresistive pattern 28, the ground-side-a-phase magnetoresistive pattern 30, the ground-side + b-phase magnetoresistive pattern 32, and the ground-side-b-phase magnetoresistive pattern 34 overlap.

In this case, since the MR chip 5 can be miniaturized, the sensor substrate 6 on which the MR chip 5 is mounted can be miniaturized, and the resin sealing member 7 covering the MR chip 5 can be miniaturized. Therefore, the cost of the package in which the MR chip 5 is mounted can be reduced. In this case, since the + a-phase magnetoresistive pattern 11, the-a-phase magnetoresistive pattern 12, the + b-phase magnetoresistive pattern 13, and the-b-phase magnetoresistive pattern 14 overlap each other, even if the intensity and direction of the external magnetic field applied to the magnetic sensor device 1 vary within the installation range of the magnetic sensor 3, it is possible to suppress a decrease in the detection accuracy of the magnetic sensor device 1.

In the case where the MR chip 5 has a two-layer structure as in the above-described embodiment, the cost of the MR chip 5 and the cost of the package on which the MR chip 5 is mounted can be reduced in a balanced manner.

(modification of magnetoresistive Pattern)

Fig. 13(a) and 13(B) are graphs showing results obtained by a simulation in which an external magnetic field is applied to the magnetic sensor device 1 according to another embodiment of the present invention.

In the above-described embodiment, each of the power supply side + a phase magnetoresistive pattern 27, the ground side + a phase magnetoresistive pattern 28, the power supply side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power supply side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power supply side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34 may be configured by two magnetoresistive patterns that are divided in the circumferential direction, may be configured by three magnetoresistive patterns that are divided in the circumferential direction, or may be configured by five or more magnetoresistive patterns that are divided in the circumferential direction.

That is, if n is an integer of 2 or more, each of the power supply side + a phase magnetoresistive pattern 27, the ground side + a phase magnetoresistive pattern 28, the power supply side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power supply side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power supply side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34 may be formed of n magnetoresistive patterns that are divided in the circumferential direction.

In this case, it is desirable that the n first magnetoresistive patterns constituting the power-supply-side + a-phase magnetoresistive pattern 27 be arranged at λ/2n pitches in the circumferential direction, the n second magnetoresistive patterns constituting the ground-side + a-phase magnetoresistive pattern 28 be arranged at λ/2n pitches in the circumferential direction, the n third magnetoresistive patterns constituting the power-supply-side-a-phase magnetoresistive pattern 29 be arranged at λ/2n pitches in the circumferential direction, the n fourth magnetoresistive patterns constituting the ground-side-a-phase magnetoresistive pattern 30 be arranged at λ/2n pitches in the circumferential direction, the n fifth magnetoresistive patterns constituting the power-supply-side + b-phase magnetoresistive pattern 31 be arranged at λ/2n pitches in the circumferential direction, the n sixth magnetoresistive patterns constituting the ground-side + b-phase magnetoresistive pattern 32 be arranged at λ/2n pitches in the circumferential direction, the n seventh magnetoresistive patterns constituting the power-side-b-phase magnetoresistive pattern 33 be arranged at λ/2n pitches in the circumferential direction, the n eighth magnetoresistive patterns constituting the ground-side-b-phase magnetoresistive pattern 34 are arranged at a λ/2n pitch in the circumferential direction.

In this case, it is preferable that the longitudinal direction of the conductor of each of the n first magnetoresistive patterns, the longitudinal direction of the conductor of each of the n second magnetoresistive patterns, the longitudinal direction of the conductor of each of the n third magnetoresistive patterns, the longitudinal direction of the conductor of each of the n fourth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n fifth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n sixth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n seventh magnetoresistive patterns, and the longitudinal direction of the conductor of each of the n eighth magnetoresistive patterns are changed by 180/n ° toward, for example, the counterclockwise direction.

In this case, as in the above-described embodiment, the influence of the external magnetic field can be effectively canceled at each of the power supply side + a phase magnetoresistive pattern 27, the ground side + a phase magnetoresistive pattern 28, the power supply side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power supply side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power supply side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34, as a result, it is possible to effectively reduce the influence of the external magnetic field acting on each of the ground side + a phase magnetoresistive pattern 28, the power side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34.

In this case, similarly to the above-described embodiment, since the n first magnetoresistive patterns, the n second magnetoresistive patterns, the n third magnetoresistive patterns, the n fourth magnetoresistive patterns, the n fifth magnetoresistive patterns, the n sixth magnetoresistive patterns, the n seventh magnetoresistive patterns, and the n eighth magnetoresistive patterns are arranged at equivalent positions of the rotating magnetic fields H1, H2, it is possible to prevent the output of the magnetic sensor 3 from being lowered.

In the magnetic sensor device 1 in which each of the power supply side + a phase magnetoresistive pattern 27, the ground side + a phase magnetoresistive pattern 28, the power supply side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power supply side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power supply side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34 is formed of two magnetoresistive patterns, that is, in the magnetic sensor device 1 in which two magnetoresistive patterns are arranged at a λ/4 pitch and the longitudinal direction of the conductor of each of the two magnetoresistive patterns is changed by, for example, 90 ° toward the counterclockwise direction side, when simulation is performed under the same condition as the above, in the magnetic sensor device 1, as shown in fig. 13(a), an error is generated by about 0.7 ° at maximum. As is clear from the results of the simulation, the magnetic sensor device 1 can suppress a decrease in detection accuracy of the magnetic sensor device 1 as compared with the magnetic sensor device of the related art.

In addition, in the magnetic sensor device 1 in which each of the power supply side + a phase magnetoresistive pattern 27, the ground side + a phase magnetoresistive pattern 28, the power supply side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power supply side + B phase magnetoresistive pattern 31, the ground side + B phase magnetoresistive pattern 32, the power supply side-B phase magnetoresistive pattern 33, and the ground side-B phase magnetoresistive pattern 34 is formed of three magnetoresistive patterns, that is, in the magnetic sensor device 1 in which the three magnetoresistive patterns are arranged at a λ/6 pitch and the longitudinal direction of the conductor of each of the three magnetoresistive patterns is changed by 60 ° toward the counterclockwise direction side, when simulation is performed under the same condition as the above, in the magnetic sensor device 1, as shown in fig. 13(B), an error is generated by about 0.4 ° at the maximum. As is clear from the simulation results, the magnetic sensor device 1 can suppress a decrease in detection accuracy of the magnetic sensor device 1 as compared with the magnetic sensor device of the related art.

When the power supply side + a phase magnetoresistive pattern 27, the ground side + a phase magnetoresistive pattern 28, the power supply side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power supply side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power supply side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34 are each formed of n magnetoresistive patterns, the n magnetoresistive patterns may be arranged at a pitch other than the λ/2n pitch in the circumferential direction.

When the power supply side + a phase magnetoresistive pattern 27, the ground side + a phase magnetoresistive pattern 28, the power supply side-a phase magnetoresistive pattern 29, the ground side-a phase magnetoresistive pattern 30, the power supply side + b phase magnetoresistive pattern 31, the ground side + b phase magnetoresistive pattern 32, the power supply side-b phase magnetoresistive pattern 33, and the ground side-b phase magnetoresistive pattern 34 are each formed of n magnetoresistive patterns, the longitudinal direction of the conductor of each of the n magnetoresistive patterns may be changed at an angle other than 180/n °. The angle in this case may or may not be constant.

In addition, the number of magnetoresistive patterns constituting the power source side + a phase magnetoresistive pattern 27, the number of magnetoresistive patterns constituting the ground side + a phase magnetoresistive pattern 28, the number of magnetoresistive patterns constituting the power source side-a phase magnetoresistive pattern 29, the number of magnetoresistive patterns constituting the ground side-a phase magnetoresistive pattern 30, the number of magnetoresistive patterns constituting the power source side + b phase magnetoresistive pattern 31, the number of magnetoresistive patterns constituting the ground side + b phase magnetoresistive pattern 32, the number of magnetoresistive patterns constituting the power source side-b phase magnetoresistive pattern 33, and the number of magnetoresistive patterns constituting the ground side-b phase magnetoresistive pattern 34 are not necessarily the same.

(modification of magnetic sensor and modification of magnetic sensor device)

Fig. 14 is a schematic diagram for explaining the configuration of a magnetic sensor 3 according to another embodiment of the present invention. Fig. 15 is a schematic diagram for explaining the configuration of a magnetic sensor device 1 according to another embodiment of the present invention.

In the above-described embodiment, the sensor substrate 6 on which the MR chip 5 is mounted may be a flexible printed board (see fig. 14). In this case, the magnetic sensor 3 can be easily mounted on the magnetic sensor device 1.

In the above-described embodiment, the magnetic sensor device 1 may be a linear encoder. In this case, as shown in fig. 15, the magnetic scale 2 is formed linearly. In this case, the magnetic sensor 3 is relatively moved with respect to the magnetic scale 2 in the longitudinal direction of the magnetic scale 2. That is, in this case, the longitudinal direction of the linear magnetic scale 2 is the relative movement direction of the magnetic sensor 3 with respect to the magnetic scale 2, and the width direction of the magnetic scale 2 orthogonal to the longitudinal direction of the magnetic scale 2 is the orthogonal direction orthogonal to the relative movement direction of the magnetic sensor 3 with respect to the magnetic scale 2.

In this case, the four magnetoresistive patterns 27a to 27d, the four magnetoresistive patterns 28a to 28d, the four magnetoresistive patterns 29a to 29d, the four magnetoresistive patterns 30a to 30d, the four magnetoresistive patterns 31a to 31d, the four magnetoresistive patterns 32a to 32d, the four magnetoresistive patterns 33a to 33d, and the four magnetoresistive patterns 34a to 34d are each arranged in a straight line. In this case, the sum of the width of one N pole and the width of one S pole in the longitudinal direction of the magnetic scale 2 is λ (see fig. 15), and the diameters of the circular regions RA1 and RA2 are λ/8. In fig. 15, the same components as those of the above-described embodiment are denoted by the same reference numerals.

(other embodiments)

The above embodiment is an example of the best mode of the present invention, but is not limited thereto, and various modifications can be made without departing from the scope of the present invention.

In the above-described embodiment, the magnetic scale 2 may have three or more tracks. In the above-described embodiment, the magnetoresistive patterns 27a to 27d, 28a to 28d, 29a to 29d, 30a to 30d, 31a to 31d, 32a to 32d, 33a to 33d, and 34a to 34d may be formed in shapes other than rectangles. For example, the magnetoresistive patterns 27a to 27d, 28a to 28d, 29a to 29d, 30a to 30d, 31a to 31d, 32a to 32d, 33a to 33d, and 34a to 34d may be formed in a circular shape so as to fit into the circular regions RA1 and RA 2.

In the above-described embodiment, the magnetoresistive patterns 27a to 27d are connected in series in this order, but the magnetoresistive patterns 27a to 27d may be connected in series in a random order. For example, the magnetoresistive pattern 27a and the magnetoresistive pattern 27c may be connected in series, the magnetoresistive pattern 27b and the magnetoresistive pattern 27d may be connected in series, and the magnetoresistive pattern 27b and the magnetoresistive pattern 27c may be connected in series. Similarly, the magnetoresistive patterns 28a to 28d, 29a to 29d, 30a to 30d, 31a to 31d, 32a to 32d, and 34a to 34d may be connected in series in a random order.

In the above embodiment, the magnetoresistive patterns 27a to 27d are connected in parallel, the magnetoresistive patterns 28a to 28d are connected in parallel, the magnetoresistive patterns 29a to 29d are connected in parallel, the magnetoresistive patterns 30a to 30d are connected in parallel, the magnetoresistive patterns 31a to 31d are connected in parallel, the magnetoresistive patterns 32a to 32d are connected in parallel, the magnetoresistive patterns 33a to 33d are connected in parallel, and the magnetoresistive patterns 34a to 34d are connected in parallel.

In the above-described embodiment, the + a-phase magnetoresistive pattern 11 and the + b-phase magnetoresistive pattern 13 may be formed in the first magnetoresistive pattern layer 37, and the-a-phase magnetoresistive pattern 12 and the-b-phase magnetoresistive pattern 14 may be formed in the second magnetoresistive pattern layer 38. In the above-described embodiment, the + a-phase magnetoresistive pattern 11 and the-a-phase magnetoresistive pattern 12 may be formed in the first magnetoresistive pattern layer 37, and the + b-phase magnetoresistive pattern 13 and the-b-phase magnetoresistive pattern 14 may be formed in the second magnetoresistive pattern layer 38.

Claims (9)

1. A magnetic sensor device, characterized in that,

the disclosed device is provided with: a magnetic scale formed in a circular shape or a linear shape; and a magnetic sensor disposed opposite to the magnetic scale,

wherein the magnetic sensor is relatively moved with respect to the magnetic scale in a circumferential direction of the magnetic scale when the magnetic scale is formed in a circular ring shape or a circular shape, and the magnetic sensor is relatively moved with respect to the magnetic scale in a longitudinal direction of the magnetic scale when the magnetic scale is formed in a linear shape,

the magnetic scale is provided with a plurality of magnetic tracks, and the N poles and S poles of the plurality of magnetic tracks are alternately arranged with the same width in the relative movement direction of the magnetic sensor relative to the magnetic scale,

the plurality of tracks are arranged adjacently in a direction orthogonal to the relative movement direction,

in the tracks adjacent in the orthogonal direction, the positions of the N pole and the S pole are shifted by one magnetic pole in the relative movement direction,

generating a rotating magnetic field in which a direction of a magnetic vector in an in-plane direction parallel to an opposing surface of the magnetic scale opposing the magnetic sensor changes in the relative movement direction at a predetermined position of the track in the orthogonal direction,

the magnetic sensor includes an A-phase magnetoresistive pattern and a B-phase magnetoresistive pattern having a phase difference of 90 DEG therebetween,

the A-phase magnetoresistive pattern includes a + a-phase magnetoresistive pattern and a-phase magnetoresistive pattern for detecting relative movement of the magnetic sensor with respect to the magnetic scale with a phase difference of 180 DEG,

the B-phase magnetoresistive pattern includes a + B-phase magnetoresistive pattern and a-B-phase magnetoresistive pattern for detecting relative movement of the magnetic sensor with respect to the magnetic scale with a phase difference of 180 DEG,

the + a phase magnetoresistive pattern is composed of a power source side + a phase magnetoresistive pattern disposed on the power source side of a midpoint position of the + a phase magnetoresistive pattern, and a ground side + a phase magnetoresistive pattern disposed on the ground side of the midpoint position of the + a phase magnetoresistive pattern,

the-a phase magnetoresistive pattern is composed of a power source side-a phase magnetoresistive pattern disposed at a position closer to a power source side than a midpoint position of the-a phase magnetoresistive pattern, and a ground side-a phase magnetoresistive pattern disposed at a position closer to a ground side than the midpoint position of the-a phase magnetoresistive pattern,

the + b-phase magnetoresistive pattern includes a power source-side + b-phase magnetoresistive pattern disposed on a power source side of a midpoint position of the + b-phase magnetoresistive pattern, and a ground-side + b-phase magnetoresistive pattern disposed on a ground side of the midpoint position of the + b-phase magnetoresistive pattern,

the-b-phase magnetoresistive pattern includes a power-side-b-phase magnetoresistive pattern disposed on a power side with respect to a midpoint position of the-b-phase magnetoresistive pattern, and a ground-side-b-phase magnetoresistive pattern disposed on a ground side with respect to the midpoint position of the-b-phase magnetoresistive pattern,

the power supply side + a phase magnetoresistive pattern, the ground side + a phase magnetoresistive pattern, the power supply side-a phase magnetoresistive pattern, the ground side-a phase magnetoresistive pattern, the power supply side + b phase magnetoresistive pattern, the ground side + b phase magnetoresistive pattern, the power supply side-b phase magnetoresistive pattern, and the ground side-b phase magnetoresistive pattern are arranged at positions where the rotating magnetic field is generated in the orthogonal direction,

the power source side + a phase magnetoresistive pattern is constituted by a plurality of block-shaped first magnetoresistive patterns that are segmented in the relative movement direction,

the ground side + a phase magnetoresistive pattern is constituted by a plurality of block-shaped second magnetoresistive patterns that are segmented in the relative movement direction,

the power source side-a phase magnetoresistive pattern is constituted by a plurality of block-shaped third magnetoresistive patterns that are segmented in the relative movement direction,

the ground-side-a-phase magnetoresistive pattern is constituted by a plurality of block-shaped fourth magnetoresistive patterns that are segmented in the relative movement direction,

the power source side + b phase magnetoresistive pattern is constituted by a plurality of block-shaped fifth magnetoresistive patterns which are segmented in the relative movement direction,

the ground side + b phase magnetoresistive pattern is constituted by a plurality of block-shaped sixth magnetoresistive patterns that are segmented in the relative movement direction,

the power source side-b phase magnetoresistive pattern is constituted by a plurality of block-shaped seventh magnetoresistive patterns that are segmented in the relative movement direction,

the ground-side-b-phase magnetoresistive pattern is composed of a plurality of block-shaped eighth magnetoresistive patterns that are segmented in the relative movement direction,

the first magnetoresistive pattern, the second magnetoresistive pattern, the third magnetoresistive pattern, the fourth magnetoresistive pattern, the fifth magnetoresistive pattern, the sixth magnetoresistive pattern, the seventh magnetoresistive pattern, and the eighth magnetoresistive pattern are each formed by folding back a plurality of times a linear conductor having a longitudinal direction in a predetermined direction,

in each of the plurality of first magnetoresistive patterns, the plurality of second magnetoresistive patterns, the plurality of third magnetoresistive patterns, the plurality of fourth magnetoresistive patterns, the plurality of fifth magnetoresistive patterns, the plurality of sixth magnetoresistive patterns, the plurality of seventh magnetoresistive patterns, and the plurality of eighth magnetoresistive patterns, if the magnetoresistive pattern disposed on the most one end side in the relative movement direction is set as one-end-side magnetoresistive pattern, the magnetoresistive pattern disposed on the most other end side in the relative movement direction is set as the other-end-side magnetoresistive pattern, and when the magnetic scale is formed in an annular or circular shape, a central angle formed by one N-pole and one S-pole adjacent in the circumferential direction of the magnetic scale with respect to the center of the magnetic scale is set as λ, and when the magnetic scale is formed in a linear shape, a sum of a width of the one N-pole and a width of the one S-pole in the relative movement direction is set as λ, the plurality of the first magnetoresistance patterns, the plurality of the second magnetoresistance patterns, the plurality of the third magnetoresistance patterns, the plurality of the fourth magnetoresistance patterns, the plurality of the fifth magnetoresistance patterns, the plurality of the sixth magnetoresistance patterns, the plurality of the seventh magnetoresistance patterns, and the plurality of the eighth magnetoresistance patterns are each arranged in a range of λ/2 in the relative movement direction,

a longitudinal direction of the conductor of each of the plurality of first magnetoresistive patterns, a longitudinal direction of the conductor of each of the plurality of second magnetoresistive patterns, a longitudinal direction of the conductor of each of the plurality of third magnetoresistive patterns, a longitudinal direction of the conductor of each of the plurality of fourth magnetoresistive patterns, a longitudinal direction of the conductor of each of the plurality of fifth magnetoresistive patterns, a longitudinal direction of the conductor of each of the plurality of sixth magnetoresistive patterns, a longitudinal direction of the conductor of each of the plurality of seventh magnetoresistive patterns, and a longitudinal direction of the conductor of each of the plurality of eighth magnetoresistive patterns are changed by a predetermined angle in a constant direction from the one-end magnetoresistive pattern toward the other-end magnetoresistive pattern,

if n is an integer of 2 or more, then

The power supply side + a phase magnetoresistive pattern is composed of n of the first magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction,

the ground side + a phase magnetoresistive pattern is constituted by n second magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction,

the power source side-a phase magnetoresistive pattern is composed of n of the third magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction,

the ground-side-a-phase magnetoresistive pattern is composed of n of the fourth magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction,

the power source side + b phase magnetoresistive pattern is composed of n of the fifth magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction,

the ground side + b phase magnetoresistive pattern is composed of n of the sixth magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction,

the power source side-b phase magnetoresistive pattern is composed of n seventh magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction,

the ground-side-b-phase magnetoresistive pattern is composed of n eighth magnetoresistive patterns arranged at a λ/2n pitch in the relative movement direction,

the longitudinal direction of the conductor of each of the n first magnetoresistive patterns, the longitudinal direction of the conductor of each of the n second magnetoresistive patterns, the longitudinal direction of the conductor of each of the n third magnetoresistive patterns, the longitudinal direction of the conductor of each of the n fourth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n fifth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n sixth magnetoresistive patterns, the longitudinal direction of the conductor of each of the n seventh magnetoresistive patterns, and the longitudinal direction of the conductor of each of the n eighth magnetoresistive patterns are changed by 180/n ° from the one-end magnetoresistive pattern toward the other-end magnetoresistive pattern.

2. The magnetic sensor device according to claim 1,

the power source side + a phase magnetoresistive pattern is constituted by four of the first magnetoresistive patterns arranged at a λ/8 pitch in the relative movement direction,

the ground side + a phase magnetoresistive pattern is constituted by four of the second magnetoresistive patterns arranged at a λ/8 pitch in the relative movement direction,

the power source side-a phase magnetoresistive pattern is composed of four of the third magnetoresistive patterns arranged at a λ/8 pitch in the relative movement direction,

the ground-side-a-phase magnetoresistive pattern is composed of four of the fourth magnetoresistive patterns arranged at a λ/8 pitch in the direction of the relative movement,

the power supply side + b phase magnetoresistive pattern is composed of four of the fifth magnetoresistive patterns arranged at a λ/8 pitch in the relative movement direction,

the ground side + b phase magnetoresistive pattern is composed of four of the sixth magnetoresistive patterns arranged at a λ/8 pitch in the relative movement direction,

the power source side-b phase magnetoresistive pattern is composed of four of the seventh magnetoresistive patterns arranged at a λ/8 pitch in the relative movement direction,

the ground side-b phase magnetoresistive pattern is composed of four of the eighth magnetoresistive patterns arranged at a λ/8 pitch in the direction of the relative movement,

the longitudinal direction of the conductor of each of the four first magnetoresistive patterns, the longitudinal direction of the conductor of each of the four second magnetoresistive patterns, the longitudinal direction of the conductor of each of the four third magnetoresistive patterns, the longitudinal direction of the conductor of each of the four fourth magnetoresistive patterns, the longitudinal direction of the conductor of each of the four fifth magnetoresistive patterns, the longitudinal direction of the conductor of each of the four sixth magnetoresistive patterns, the longitudinal direction of the conductor of each of the four seventh magnetoresistive patterns, and the longitudinal direction of the conductor of each of the four eighth magnetoresistive patterns are changed by 45 ° from the one-end magnetoresistive pattern toward the other-end magnetoresistive pattern.

3. The magnetic sensor device according to claim 1,

the first, second, third, fourth, fifth, sixth, seventh, and eighth magnetoresistance patterns are respectively formed to include a circular region having a diameter defined by λ/2 n.

4. The magnetic sensor device according to claim 1,

the first magnetoresistive patterns are connected in series, the second magnetoresistive patterns are connected in series, the third magnetoresistive patterns are connected in series, the fourth magnetoresistive patterns are connected in series, the fifth magnetoresistive patterns are connected in series, the sixth magnetoresistive patterns are connected in series, the seventh magnetoresistive patterns are connected in series, and the eighth magnetoresistive patterns are connected in series.

5. The magnetic sensor device according to any one of claims 1 to 4,

the magnetic sensor includes a first magnetoresistive pattern layer in which any two magnetoresistive patterns of the + a-phase magnetoresistive pattern, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern are formed, and a second magnetoresistive pattern layer in which two magnetoresistive patterns other than the two magnetoresistive patterns formed in the first magnetoresistive pattern layer among the + a-phase magnetoresistive pattern, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern are formed,

the first and second magnetoresistance pattern layers are stacked such that a magnetoresistance pattern formed on the first magnetoresistance pattern layer and a magnetoresistance pattern formed on the second magnetoresistance pattern layer overlap.

6. The magnetic sensor device according to any one of claims 1 to 4,

the magnetic sensor includes a common magnetoresistive pattern layer that forms the + a-phase magnetoresistive pattern, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern.

7. The magnetic sensor device according to any one of claims 1 to 4,

the magnetic sensor includes: a first magnetoresistance pattern layer on which the + a phase magnetoresistance pattern is formed; a second magnetoresistance pattern layer on which the-a phase magnetoresistance pattern is formed; a third magnetoresistance pattern layer on which the + b phase magnetoresistance pattern is formed; and a fourth magnetoresistance pattern layer formed with the-b phase magnetoresistance pattern,

the first, second, third, and fourth magnetoresistive pattern layers are stacked such that the + a-phase magnetoresistive pattern, the-a-phase magnetoresistive pattern, the + b-phase magnetoresistive pattern, and the-b-phase magnetoresistive pattern overlap.

8. The magnetic sensor device according to any one of claims 1 to 4,

the magnetic scale is formed into a circular ring shape or a circular shape,

the plurality of first magnetoresistive patterns, the plurality of second magnetoresistive patterns, the plurality of third magnetoresistive patterns, the plurality of fourth magnetoresistive patterns, the plurality of fifth magnetoresistive patterns, the plurality of sixth magnetoresistive patterns, the plurality of seventh magnetoresistive patterns, and the plurality of eighth magnetoresistive patterns are arranged in a circular arc shape, respectively.

9. The magnetic sensor device according to any one of claims 1 to 4,

the magnetic scale is formed in a linear shape,

the plurality of first magnetoresistive patterns, the plurality of second magnetoresistive patterns, the plurality of third magnetoresistive patterns, the plurality of fourth magnetoresistive patterns, the plurality of fifth magnetoresistive patterns, the plurality of sixth magnetoresistive patterns, the plurality of seventh magnetoresistive patterns, and the plurality of eighth magnetoresistive patterns are arranged in a straight line, respectively.

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