JP5875947B2 - Magnetic sensor device - Google Patents

Description

  The present invention relates to a magnetic sensor device.

  As a conventional technique, a moving magnet that is attached to a detection target and moves within a certain radius on a plane, and a magnetic sensor that detects a change in a magnetic vector due to a change in the position of the moving magnet are provided. There is known a magnetic coordinate position detection device packaged with a plurality of anisotropic magnetoresistive elements and bias magnets formed in (see, for example, Patent Document 1).

  In this magnetic coordinate position detection apparatus, since the magnetic sensor is formed by packaging together with a plurality of anisotropic magnetoresistive elements and bias magnets formed on the substrate, the sensitivity can be increased.

JP 2009-150786 A

  However, in order to reduce the size of the conventional magnetic coordinate position detection device so as not to deteriorate the sensitivity, it is necessary to reduce the size of the bias magnet and to generate a magnetic field equivalent to that before the size reduction. It was difficult.

  Accordingly, an object of the present invention is to provide a magnetic sensor device that can accurately detect the operation switching position and can be miniaturized.

One embodiment of the present invention includes a first magnetic sensor having a plurality of magnetoresistive elements whose magnetoresistance values change based on the direction of a magnetic vector on the first detection surface, and a first detection surface including the first detection surface. The distance from the straight line obtained by projecting the center of the first surface facing the first magnetic sensor onto the plane is the second plane whose normal is the straight line. A first magnetic vector generator that is attached to the detection target so as to be longer than the distance from the first side surface on the side of the intersecting first magnetic sensor to the center, and generates a radial magnetic vector on the first plane; The first magnetic vector generation unit is provided so as to protrude from the first side surface, and the first side surface side is shorter than the first side surface width, and only the first magnetic vector generation unit is provided. The magnetic vector whose spread is suppressed compared to the first detection surface A second magnetic vector generation unit for antibody, a straight line axis of symmetry, provided at a position axisymmetric to the first magnetic sensor, the direction of magnetic vectors in the second detection surface included in a first plane A second magnetic sensor having a plurality of magnetoresistive elements whose magnetoresistance values change based on the second magnetic sensor, and a second magnetic sensor that protrudes from the second side opposite to the first side of the first magnetic vector generator, The third side surface generates a magnetic vector whose width on the second side surface is shorter than the width of the second side surface and whose spread is suppressed compared to the case of only the first magnetic vector generation unit on the second detection surface. And a magnetic vector generator .

  According to the present invention, it is possible to accurately detect the operation switching position and reduce the size.

FIG. 1A is a top view of the magnetic sensor device according to the first embodiment, and FIG. 1B is a schematic view of the magnetic sensor device viewed from the front. FIG. 2A is an equivalent circuit diagram of the first magnetic sensor according to the first embodiment, and FIG. 2B is a schematic diagram for explaining the magnetic sensing part of the first magnetoresistive element. is there. 3A is a block diagram of the magnetic sensor device according to the first embodiment, FIG. 3B is a top view when the operation unit is operated to the switching position, and FIG. It is a graph which shows the relationship between the output of a 1st magnetic sensor, and the stroke (mm) of an operation part. FIG. 4A is a top view of the magnetic sensor device according to the second embodiment, and FIG. 4B is a top view showing a case where the magnetic sensor device is operated to the switching position of the first magnetic sensor. (c) is a top view showing a case where the second magnetic sensor is operated to the switching position, and (d) is an output of the first magnetic sensor and the second magnetic sensor and a stroke (mm) of the operation unit. It is a graph which shows the relationship.

(Summary of embodiment)
A magnetic sensor device according to an embodiment includes a first magnetic sensor having a plurality of magnetoresistive elements whose magnetoresistance values change based on the direction of a magnetic vector on the first detection surface, and the first detection surface. The distance from the straight line obtained by projecting the center of the first surface facing the first magnetic sensor to the first plane and the element center of the first magnetic sensor is the second normal to the straight line. A first magnetic vector that is attached to the detection target so as to be longer than the distance from the first side surface on the first magnetic sensor side that intersects the first plane to the center, and generates a radial magnetic vector on the first plane The first magnetic vector generator is provided so as to protrude from the first side of the generator and the first magnetic vector generator, and the first side is shorter than the first side. Magnetic vector with reduced spread compared to And it includes a second magnetic vector generation unit for generating a first detection surface.

  Since this magnetic sensor device can generate a magnetic vector whose spread is suppressed on the first detection surface of the first magnetic sensor, it can accurately detect the operation switching position and can be miniaturized. .

[First embodiment]
(Configuration of magnetic sensor device 1)
FIG. 1A is a top view of the magnetic sensor device according to the first embodiment, and FIG. 1B is a schematic view of the magnetic sensor device viewed from the front. A one-dot chain line illustrated in FIG. 1A indicates a reference operation position of the operation unit 4. Also, a two-dot chain line shown in FIG. 1A indicates a switching position where a difference value (described later) of the first magnetic sensor 2 is switched from plus to minus or from minus to plus. In each drawing according to the embodiment, the ratio between parts may differ from the actual ratio.

As shown in FIGS. 1A and 1B, the magnetic sensor device 1 includes a plurality of magnetoresistive elements whose magnetic resistance values change based on the direction of the magnetic vector 8 on the first detection surface (detection surface 20). The center 6a of the first surface (lower surface 61) facing the first magnetic sensor 2 is projected onto the first magnetic sensor 2 having elements and the first plane (plane 200) including the detection surface 20. the resulting distance d ₂ from the straight line 6b to the first element center 25 of the magnetic sensor 2, the first side 64 of the first magnetic sensor 2 side intersecting the second plane a straight line 6b and the normal A first magnet 6 as a first magnetic vector generation unit which is attached to the operation unit 4 so as to be longer than the distance d ₁ to the center 6a and generates a radial magnetic vector 8 on the plane 200; Provided to protrude from the first side face 64 of the magnet 6; 1 of the width W ₂ of the side surface 64 side, shorter than the width W ₁ of the first aspect 64, to generate a magnetic vector 8 spreading is suppressed as compared with the case of only the first magnet 6 to the detection surface 20 And a second magnet 7 as a second magnetic vector generator.

  The detection surface 20 is a surface including a magnetoresistive element described later. That is, the magnetoresistive element changes its magnetoresistance value mainly by changing the direction of the magnetic vector 8 in the detection surface 20.

  The straight line 6b connects a locus of the center 6a accompanying the operation of the operation unit 4 supported so as to be operable in a one-dimensional direction. Note that the operation unit 4 is not limited to be supported so as to be movable in parallel with the detection surface 20, but is accompanied by a rotational movement like an operation of tilting the operation unit 4, but the locus of the center 6a is a straight line 6b. It may be supported by. Further, the operation unit 4 may be supported so that the locus of the center 6a is a straight line 6b in the vicinity of the switching position.

  The second plane is a plane perpendicular to the paper surface of FIG. 1A at the position indicated by the alternate long and short dash line in FIG.

  The element center 25 indicates the center of gravity determined by a plurality of magnetoresistive elements described later.

(Configuration of the first magnetic sensor 2)
FIG. 2A is an equivalent circuit diagram of the first magnetic sensor according to the first embodiment, and FIG. 2B is a schematic diagram for explaining the magnetic sensing part of the first magnetoresistive element. is there.

  The first magnetic sensor 2 is provided on the installation surface 30 of the substrate 3 as shown in FIG.

  As shown in FIG. 2 (a), the first magnetic sensor 2 passes through the element center 25 of the first magnetic sensor 2 and is magnetized in one region separated by a boundary line 6c orthogonal to the straight line 6b. The first magnetoresistive element 21 and the second magnetoresistive element 22 are arranged such that the mutual magnetic sensitive portions 20a that change the resistance value form an angle of 90 °, and the mutual magnetic sensitive portions 20a are 90 in the other region. A third magnetoresistive element 23 and a fourth magnetoresistive element 24 having an angle of ° are arranged, and a bridge circuit is formed by the first magnetoresistive element 21 to the fourth magnetoresistive element 24. In addition, one area | region is an upper side of the boundary line 6c in the paper surface of Fig.1 (a) and Fig.2 (a), and the other area | region is a lower side.

  As an example, the first magnetoresistive element 21 to the fourth magnetoresistive element 24 are formed using a film containing a ferromagnetic metal such as Ni, Fe, or Co as a main component. The resistance values of the first magnetoresistive element 21 to the fourth magnetoresistive element 24 when the magnetic vector 8 is not acting are assumed to be equal.

One end of the first magnetoresistive element 21 is electrically connected to one end of the second magnetoresistive element 22. The other end of the first magnetoresistive element 21 is electrically connected to, for example, a ground circuit. The other end of the second magnetoresistive element 22 is electrically connected to, for example, a power supply circuit and supplied with a reference voltage _VCC . The first magnetoresistive element 21 and the second magnetoresistive element 22 constitute a half bridge circuit. The midpoint potential of this half-bridge circuit is V _{1 as} shown in FIG.

One end of the third magnetoresistive element 23 is electrically connected to one end of the fourth magnetoresistive element 24. The other end of the third magnetoresistive element 23 is electrically connected to, for example, a ground circuit. The other end of the fourth magnetoresistive element 24 is electrically connected to a power supply circuit, for example, and supplied with a reference voltage _VCC . The third magnetoresistive element 23 and the fourth magnetoresistive element 24 constitute a half bridge circuit. Midpoint potential of this half-bridge circuit, as shown in FIG. 2 (a), a V _2. The middle point potential V ₁ and the middle point potential V ₂ is output to the control unit 10 to be described later.

  The first magnetoresistive element 21 to the fourth magnetoresistive element 24 are arranged in different directions, but since the main configuration is the same, in the following, taking the first magnetoresistive element 21 as an example, The configuration of the magnetoresistive element will be described.

  As shown in FIG. 2B, the first magnetoresistive element 21 has a plurality of magnetic sensitive portions 20a arranged in parallel to each other. The magnetically sensitive portion 20a is a portion that is linearly formed in the vertical direction on the paper surface of FIG. 2B, and is a portion in which the magnetic resistance value changes according to the direction of the magnetic vector 8. The connecting portion 20b that connects the magnetic sensitive portion 20a and the magnetic sensitive portion 20a is formed to be shorter than the magnetic sensitive portion 20a. Therefore, the connection portion 20b is assumed to have a small change in the magnetoresistance value so as to be negligible compared to the magnetic sensing portion 20a. In addition, the connection part 20b may be formed using the electroconductive member whose magnetic resistance value does not change, for example.

  As an example, the magnetic sensitive portions 20a of the first magnetoresistive element 21 to the fourth magnetoresistive element 24 are arranged so as to have an angle of 45 ° with respect to the two-dot chain line shown in FIG. The In this case, a half bridge circuit composed of the first magnetoresistive element 21 and the second magnetoresistive element 22 is arranged in one region on the upper side of the two-dot chain line shown in FIG. A half-bridge circuit composed of the third magnetoresistive element 23 and the fourth magnetoresistive element 24 is disposed in the other region.

The first magnetoresistive element 21 and the second magnetoresistive element 22 are disposed above and below the two-dot chain line on the condition that the difference value is zero at the switching position. The magnetoresistive element 23 and the fourth magnetoresistive element 24 may be arranged above and below the two-dot chain line. This is because a magnetic vector 8 that is symmetrical above and below the alternate long and short dash line shown in FIG. 1A is generated below the second magnet 7. In other words, the difference between the middle point potential V ₁ and the middle point potential V _2, the angle of the magnetic vector 8 the operation unit 4 traverses a half-bridge circuit when located at the switching position is zero if symmetrical.

  As a modification, the first magnetoresistive element 21 and the third magnetoresistive element 23 are opposed to each other, and the second magnetoresistive element 22 and the fourth magnetoresistive element 24 are opposed to each other. A magnetic vector 8 passing through the center of the magnet 7 causes the first magnetoresistive element 21 and the third magnetoresistive element 23, or the magnetic sensitive parts 20 a and 90 of the second magnetoresistive element 22 and the fourth magnetoresistive element 24. You may arrange | position so that it may become °.

  Further, the number of magnetoresistive elements included in the first magnetic sensor 2 is not limited to four, and may be two or more that can form a half-bridge circuit.

(Configuration of the first magnet 6 and the second magnet 7)
The first magnet 6 and the second magnet 7 are, for example, permanent magnets such as alnico magnets, ferrite magnets, neodymium magnets, or the like, or ferrite-based, neodymium-based, samakoba-based, samarium-iron-nitrogen. A magnetic material such as a system and a synthetic resin material are mixed and molded into a desired shape. The 1st magnet 6 and the 2nd magnet 7 are integrally formed as an example. The second magnet 7 may be attached with a resin material or the like interposed between the second magnet 7 and the first magnet 6.

As shown in FIGS. 1A and 1B, the first magnet 6 has a front face 62 and a rear face 63 having a width D ₁ , a first side face 64 and a second side face 65 having a width W ₁ , and a high width. It is a quadrangular prism shape with a height of H. As an example, the first magnet 6 has a shape in which the width W ₁ is longer than the width D ₁ . The first magnet 6 is attached to the operation unit 4.

The second magnet 7 is provided so as to protrude from the first side face 64 of the first magnet 6. As shown in FIGS. 1A and 1B, the second magnet 7 has a front surface 72 and a rear surface 73 with a width D ₂ , a first side surface 74 and a second side surface 75 with a width W ₂ , It is a quadrangular prism shape with a height of H. The second magnet 7, as an example, the width D ₂ has a shape longer than the width W _2. The width _{W 1} is longer than the width _{W 2.} Furthermore width D ₁ and the width D _2, as an example, is approximately the same length. The second magnet 7 is disposed at the center in the width direction of the first side face 64 of the first magnet 6.

  In the first magnet 6 and the second magnet 7, the first magnetic sensor 2 side is the first magnetic pole, and the opposite side is the second magnetic pole. Specifically, as shown in FIG. 1B, the first magnet 6 and the second magnet 7 are magnetized so that the lower surface 61 and the lower surface 71 side on the first magnetic sensor 2 side are N poles, and the upper surface 60 and the upper surface 70 side are magnetized to the south pole. That is, the first magnet 6 and the second magnet 7 are magnetized in the vertical direction on the paper surface of FIG. The first magnet 6 and the second magnet 7 may have opposite magnetization directions.

  Since the first magnet 6 generates a magnetic field radially from the center of the lower surface 61, the magnetic vector 8 is directed radially outward from the center of the lower surface 61. However, a part of the magnetic vector 8 on the first side face 64 side is directed toward the first side face 74 side of the second magnet 7. Therefore, the magnetic vector 8 directed from the first side face 64 side of the first magnet 6 toward the first side face 74 of the second magnet 7 is transferred to the other side face (front face 62, rear face 63) of the first magnet 6. And the spread is suppressed compared with the magnetic vector 8 toward the second side surface 65). The first magnetic sensor 2 is arranged such that a magnetic vector 8 whose spread is suppressed is generated on the detection surface 20 when the operation unit 4 is operated to the switching position. This is because the magnetic field is stronger than in other regions and the switching position detection accuracy is improved.

The first magnetic sensor 2 is equal when a straight line passing through the center of the first side surface 74 and the second side surface 75 of the second magnet 7 and parallel to the boundary line 6c coincides with the boundary line 6c. and it outputs a midpoint potential _{V 1} and the middle point potential _{V 2.}

(Configuration of control unit 10)
3A is a block diagram of the magnetic sensor device according to the first embodiment, FIG. 3B is a top view when the operation unit is operated to the switching position, and FIG. It is a graph which shows the relationship between the output of a 1st magnetic sensor, and the stroke (mm) of an operation part. In FIG. 3C, the vertical axis represents output, and the horizontal axis represents stroke (mm). In FIG. 3C, M _{1 to} M ₇ with rhombus marks indicate measured values. In FIG. 3C, the operation position where the stroke becomes zero is the reference position, and the operation position where the output becomes zero is the switching position. For example, the distance L between the reference position and the switching position is approximately 0.32 mm.

As shown in FIG. 3A, the magnetic sensor device 1 includes a control unit 10. For example, the control unit 10 is provided on the installation surface 30 of the substrate 3. Moreover, the control part 10 is electrically connected with the magnetic sensor 2, as shown to Fig.3 (a). As an example, the control unit 10 is configured to calculate a difference (= V ₂ −V ₁ ) based on the midpoint potential V ₁ and the midpoint potential V ₂ acquired from the magnetic sensor 2. For example, the control unit 10 is configured to output a control signal indicating Lo when the difference is less than or equal to zero, and to output a control signal indicating Hi when the difference is greater than zero.

  Below, operation | movement of the magnetic sensor apparatus 1 is demonstrated, referring each figure.

(Operation)
When the operation unit 4 is operated from the reference position toward the switching position, the point where the center 6a of the first magnet 6 is projected onto the plane 200 including the detection surface 20 moves toward the switching position. When the point reaches the switching position, that is, when the operation unit 4 is operated to the switching position, as shown in FIG. 3B, the first magnetoresistive element 21 and the third magnetoresistive element 23 are crossed. The angles of the magnetic vectors 8 are substantially equal, and the angles of the magnetic vectors 8 across the second magnetoresistive element 22 and the fourth magnetoresistive element 24 are substantially equal. When in this state, the middle point potential V ₁ and the middle point potential V _2, because substantially equal, the difference becomes zero.

Thus the control unit 10 calculates the difference between the middle point potential V ₁ and the middle point potential V ₂ obtained from the magnetic sensor 2, M ₁ as shown in FIG. 3 (c), towards the switching position from the reference position To get a zero difference value. The control unit 10 outputs a control signal indicating Lo at the operation position from the reference position to the switching position.

Further, the control unit 10 obtains the operation unit 4 is operated beyond the switching position, as shown in FIG. 3 (c), a difference value M ₇ from zero. Therefore, the control unit 10 outputs a control signal indicating Hi when operated beyond the switching position.

(Effects of the first embodiment)
The magnetic sensor device 1 according to the present embodiment can detect an operation switching position with high accuracy and can be miniaturized. Specifically, when the operation unit 4 is operated to the switching position, the magnetic sensor device 1 can generate the magnetic vector 8 whose spread is suppressed on the detection surface 20 of the first magnetic sensor 2. Accordingly, the first magnetic sensor 2 has a smaller spread than other regions, in other words, a magnetic field having a higher magnetic flux density than the other regions acts, so that the operation position of the operation unit 4 can be detected with high accuracy. Can do.

  Further, the magnetic sensor device 1 does not require a bias magnet or the like for improving the sensitivity of the first magnetic sensor 2, and can improve the sensitivity by providing the second magnet 7 on the first magnet 6. Therefore, it can be downsized.

[Second Embodiment]
The second embodiment is different from the first embodiment in that the number of magnetic sensors and magnets is increased.

FIG. 4A is a top view of the magnetic sensor device according to the second embodiment, and FIG. 4B is a top view showing a case where the magnetic sensor device is operated to the switching position of the first magnetic sensor. (c) is a top view showing a case where the second magnetic sensor is operated to the switching position, and (d) is an output of the first magnetic sensor and the second magnetic sensor and a stroke (mm) of the operation unit. It is a graph which shows the relationship. In FIG. 4D, the vertical axis represents output, and the horizontal axis represents stroke (mm). In FIG. 4D, M _{1 to} M ₇ with rhombus marks are measured outputs of the first magnetic sensor 2, and M _{1a to} M _7a with square marks are measured. Is the output of the second magnetic sensor 2a. In the embodiment described below, parts having the same functions and configurations as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and description thereof is omitted. For example, the third magnet 7 a has the same sign as that of the second magnet 7, but the reference numerals of the side surfaces and the like are the same as those of the second magnet 7. Further, since the second magnetic sensor 2 a uses a magnetoresistive element having the same size as the first magnetic sensor 2, the reference numeral is the same as that of the first magnetic sensor 2.

  As shown in FIGS. 4A to 4C, the magnetic sensor device 1 according to the present embodiment includes a second magnetic sensor 2a, a third magnet 7a as a third magnetic vector generator, Is generally configured.

  The second magnetic sensor 2 a is provided at a line-symmetrical position of the first magnetic sensor 2 with the straight line 6 b as an axis of symmetry, and the magnetic vector 8 on the detection surface 20 c as the second detection surface included in the plane 200. A plurality of magnetoresistive elements whose magnetoresistance values change based on the direction of the As shown in FIG. 4A, the second magnetic sensor 2a is arranged alongside the first magnetic sensor 2 along the boundary line 6c.

Similar to the first magnetic sensor 2, the second magnetic sensor 2 a includes a first magnetoresistive element 21 to a fourth magnetoresistive element 24 as a plurality of magnetoresistive elements. The second magnetic sensor 2a is provided at a line-symmetric position of the first magnetic sensor 2, the reference voltage _VCC is supplied to the first magnetoresistive element 21 side, and the second magnetoresistive element 22 side is grounded. In addition, the arrangement is such that the switching position 6c is folded around the symmetry axis. The second magnetic sensor 2a is electrically connected to the control unit 10. The arrangement of the first magnetoresistive element 21 to the fourth magnetoresistive element 24 is not limited to this, and any arrangement may be used as long as the difference becomes zero when the third magnet 7a reaches the switching position.

Third magnet 7a is provided so as to protrude from the second side 65 opposite the first side surface 64 of the first magnet 6, the second side surface 65 side width W ₃ of, the second A magnetic vector 8 that is shorter than the width W _{1 of the} side surface 65 and suppressed in comparison with the case of only the first magnet 6 is generated on the detection surface 20c as the second detection surface. The width W ₃ being, for example, is the same as the width W ₂ of the second magnet 7 is not limited thereto.

Further, as shown in FIG. 4A, the third magnet 7a is provided at a position different from the point-symmetrical position of the second magnet 7 with the 6a center of the first magnet 6 as a symmetric point. That is, as shown in FIG. 4 (a), the distance to the switching position of the second magnet 7 is L _1, the distance to the switching position of the third magnet 7a, the distance L ₁ is different from L ₂ It is. This distance _{L 2} is, for example, is longer than dL distance _{L 1.}

  The first magnet 6 generates a magnetic vector 8 radially from its center 6a. However, the magnetic vector 8 directed to the second side surface 65 provided with the third magnet 7a is bent by the third magnet 7a. , The spread is suppressed. Therefore, when the operation unit 4 is operated to the switching position of the second magnetic sensor 2a, the second magnetic sensor 2a detects the switching position because the magnetic vector 8 whose spread is suppressed acts on the detection surface 20c. Accuracy is improved.

That is, the second magnetic sensor 2a passes through the center of the first side surface 74 and the second side surface 75 of the third magnet 7a and is parallel to the boundary line 6c, and the boundary line 6c matches. and it outputs the same midpoint potential _{V 1} and the middle point potential _{V 2.}

  The difference between the switching position of the first magnetic sensor 2 and the switching position of the second magnetic sensor 2a is equal to the difference dL to the switching position.

When the operation unit 4 is operated from the reference position toward the switching position of the first magnetic sensor 2, the point where the center 6a of the first magnet 6 is projected on the plane 200 moves toward the switching position. When the point reaches the switching position, as shown in FIG. 4B, the angle of the magnetic vector 8 across the first magnetoresistive element 21 and the third magnetoresistive element 23 of the first magnetic sensor 2 is substantially equal. And the angles of the magnetic vectors 8 across the second magnetoresistive element 22 and the fourth magnetoresistive element 24 of the first magnetic sensor 2 are substantially equal. When in this state, the middle point potential V ₁ and the middle point potential V ₂ of the first magnetic sensor 2, the substantially equal, the difference becomes zero.

Therefore, as shown in FIG. 4D, the difference value of the first magnetic sensor 2 changes from M ₁ to zero as it goes from the reference position to the switching position of the first magnetic sensor 2. On the other hand, as shown in FIG. 4D, the difference value of the second magnetic sensor 2a is a value between M _1a and M _2a and M _3a from the reference position toward the switching position of the first magnetic sensor 2. To change. This is because the third magnet 7 a is farther from the switching position than the second magnet 7. Accordingly, when the operation unit 4 is operated to the switching position of the first magnetic sensor 2, the difference value of the second magnetic sensor 2a is a value lower than zero.

Further, the operation unit 4 is operated, and the third magnet 7a reaches the switching position of the second magnetic sensor 2a, that is, the center of the first side surface 74 and the second side surface 75 of the third magnet 7a. When the passing straight line and the boundary line 6c coincide with each other, as shown in FIG. 4C, the magnetic vector 8 crossing the first magnetoresistive element 21 and the third magnetoresistive element 23 of the second magnetic sensor 2a is obtained. The angles are substantially equal, and the angles of the magnetic vectors 8 across the second magnetoresistive element 22 and the fourth magnetoresistive element 24 of the second magnetic sensor 2a are substantially equal. When in this state, the middle point potential V ₁ and the middle point potential V ₂ of the second magnetic sensor 2a, since substantially equal, the difference becomes zero. Therefore, as shown in FIG. 4D, the difference value of the second magnetic sensor 2 changes from a value between M _2a and M _3a to zero.

(Effect of the second embodiment)
The magnetic sensor device 1 according to the present embodiment can easily change the two switching positions by changing the attachment positions of the second magnet 7 and the third magnet 7a.

  Further, the magnetic sensor device 1 improves the accuracy of the switching position as compared to the case of shifting the position of the magnetic sensor in order to change the switching position. This is because when the magnetic sensor is formed into a chip, it is difficult to confirm the center of the element and the like, and it is difficult to displace the sensor accurately. However, in the magnetic sensor device 1, the first magnetic sensor 7 and the second magnetic sensor 7a are arranged in a straight line, and the mounting positions of the second magnet 7 and the third magnet 7a are changed, so that different switching positions are obtained. Therefore, the accuracy of the switching position is improved.

  As a modification, each of the first magnetic sensor 2 and the second magnetic sensor 2a may include a half bridge circuit. In this case, the second magnet 7 and the third magnet 7 a are arranged at symmetrical positions with respect to the first magnet 6. With this arrangement, the magnetic sensor device 1 calculates the difference between the outputs of the first magnetic sensor 2 and the second magnetic sensor 2a.

  As mentioned above, although some embodiment and modification of this invention were demonstrated, these embodiment and modification are only examples, and do not limit the invention based on a claim. These novel embodiments and modifications can be implemented in various other forms, and various omissions, replacements, changes, and the like can be made without departing from the scope of the present invention. In addition, not all combinations of features described in these embodiments and modifications are necessarily essential to the means for solving the problems of the invention. Furthermore, these embodiments and modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Magnetic sensor apparatus, 2 ... 1st magnetic sensor, 2a ... 2nd magnetic sensor, 3 ... Board | substrate, 4 ... Operation part, 6 ... 1st magnet, 6a ... Center, 6b ... Straight line, 6c ... Boundary line 7 ... 2nd magnet, 7a ... 3rd magnet, 8 ... Magnetic vector, 10 ... Control part, 20 ... Detection surface, 20a ... Magnetic sensing part, 20b ... Connection part, 20c ... Detection surface, 21-24 ... 1st to 4th magnetoresistive element, 25 ... element center, 30 ... installation surface, 60 ... upper surface, 61 ... lower surface, 62 ... front surface, 63 ... rear surface, 64 ... first side surface, 65 ... first 2 side surfaces, 70 ... upper surface, 71 ... lower surface, 72 ... front surface, 73 ... rear surface, 74 ... first side surface, 75 ... second side surface, 200 ... flat surface

Claims (4)

A first magnetic sensor having a plurality of magnetoresistive elements whose magnetoresistance values change based on the direction of the magnetic vector on the first detection surface;
The distance from the straight line obtained by projecting the center of the first surface facing the first magnetic sensor onto the first plane including the first detection surface to the element center of the first magnetic sensor Is attached to the detection object so as to be longer than the distance from the first side surface on the first magnetic sensor side intersecting with the second plane having the straight line as a normal line to the center, A first magnetic vector generator for generating a radial magnetic vector in a plane;
The first magnetic vector generator is provided so as to protrude from the first side surface, and the width of the first side surface is shorter than the width of the first side surface. A second magnetic vector generation unit for generating a magnetic vector, the spread of which is suppressed as compared with the case of only the unit, on the first detection surface;
The magnetoresistive value is changed based on the direction of the magnetic vector on the second detection surface that is provided at the line-symmetric position of the first magnetic sensor with the straight line as the axis of symmetry, and is included in the first plane. A second magnetic sensor having a plurality of magnetoresistive elements;
The first magnetic vector generation unit is provided so as to protrude from a second side surface opposite to the first side surface, and a width of the second side surface side is shorter than a width of the second side surface. A third magnetic vector generator for generating a magnetic vector on the second detection surface, the spread of which is suppressed compared to the case of only the first magnetic vector generator,
A magnetic sensor device comprising:   The first magnetic sensor has a mutual magnetic sensing portion that changes the magnetoresistance value in one region divided by a boundary line that passes through the element center of the first magnetic sensor and is orthogonal to the straight line. A first magnetoresistive element and a second magnetoresistive element that form an angle of 90 ° are arranged, and a third magnetoresistive element and a fourth magnetoresistive element that form an angle of 90 ° with respect to each other in the other region. The magnetic sensor device according to claim 1, wherein a magnetoresistive element is disposed, and a bridge circuit is formed by the first to fourth magnetoresistive elements.   2. The magnetic sensor according to claim 1, wherein the first magnetic vector generation unit and the second magnetic vector generation unit have the first magnetic sensor side as a first magnetic pole and the opposite side as a second magnetic pole. apparatus. Said third magnetic vector generation unit, the said center of the first magnetic vector generating section and symmetrical point, claims provided at a position different from the position of point symmetry of the second magnetic vector generating section 1 4. The magnetic sensor device according to any one of items 1 to 3 .

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