TW201632836A - Magnetic sensor and motor - Google Patents

Abstract

Disclosed is a magnetic sensor, which is provided with a magnetic resistance effect element. The magnetic sensor is used during a sensing magnet is fixed onto a motor at its axis end of a spin axis for reducing the offset between the centers of magnet and the magnetic sensing region of the magnetic resistance effect element when observing the axial direction of the spin axis. The magnetic sensor 11 includes: a magnetic resistance effect element; an element substrate 24, in which the aforementioned magnetic resistance effect element is formed; a box-shaped package body 25, in which the element substrate is formed; and a transparent sealing member 26, which seals an opening formed in the package body 25. An alignment mark M1 for performing alignment of the magnetic resistance effect element is formed on the element substrate 24, and the mark M1 is used for aligning the positions of an assembling part 14 of the magnetic sensor 11 in relation to the magnetic resistance effect element.

Description

Magnetic sensor and motor

The present invention relates to a magnetic sensor having a magnetoresistance effect element. Moreover, the present invention relates to a motor having the magnetic sensor.

A motor with an encoder is known (for example, refer to Patent Document 1). In the motor described in Patent Document 1, the encoder includes: a sensing magnet fixed to a shaft end of the rotating shaft; a magnetic sensor disposed opposite to the sensing magnet; and a sensor substrate for mounting magnetic sensing And a substrate holder that fixes the sensor substrate. The substrate holder is fixed to the motor housing. The magnetic sensor has a magnetoresistance effect element. In addition, a magnetic sensor having a magnetoresistance effect element and an element substrate on which a magnetoresistance effect element is formed is known as a magnetic sensor (see, for example, Patent Document 2).

Prior technical literature Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. 2012-168016

Patent Document 2: International Publication No. 2014/155886

In the motor described in Patent Document 1, when the distance between the center of the sensing magnet and the center of the magnetic induction region of the magnetoresistance effect element is large when viewed from the axial direction of the rotating shaft, the detection accuracy of the encoder is lowered. Therefore, in the motor, it is preferable that the amount of shift of the center of the sensing magnet and the center of the magnetic induction region of the magnetoresistance effect element is small when viewed from the axial direction of the rotating shaft.

Accordingly, an object of the present invention is to provide a magnetic sensor having a magnetoresistance effect element which can be used to reduce spin when a magnet is sensed to be fixed to a motor of a shaft end of a rotating shaft. The axial displacement of the rotating shaft senses the offset of the center of the magnet from the center of the magnetic sensing region of the magnetoresistance effect element. Further, an object of the present invention is to provide a motor having the magnetic sensor.

In order to solve the above problems, the magnetic sensor of the present invention has a magnetoresistive effect element, and the magnetic sensor is characterized in that it has an element substrate formed with a magnetoresistance effect element, and a box-shaped package body that accommodates a component substrate; and a transparent sealing member that seals an opening formed in the body of the package to seal the element substrate; and a mark for alignment is formed on the element substrate, the mark is used to mount the magnetoresistance effect element relative to the device The mounting parts of the magnetic sensor are aligned.

In the magnetic sensor of the present invention, the element substrate on which the magnetoresistance effect element is formed is formed with a mark for alignment, which is used to position the magnetoresistance effect element relative to the mounting member on which the magnetic sensor is mounted. quasi. Further, in the present invention, the sealing member that seals the element substrate is transparent. Therefore, in the present invention, when the magnetic sensor is attached to the mounting member, the magnetoresistance effect element can be aligned with respect to the mounting member while confirming the alignment mark. Therefore, in the present invention, it is possible to accurately mount the magnetoresistance effect element to the mounting member. As a result, in the present invention, when the magnetic sensor is applied to a motor in which the sensing magnet is fixed to the shaft end of the rotating shaft, if the mounting member is accurately attached to the rotating shaft, the self-rotating shaft can be lowered. The offset of the center of the sensing magnet from the center of the magnetic sensing region of the magnetoresistance effect element when viewed axially.

In the present invention, it is preferable that the sealing member is a transparent glass cover that is fixed to the package body so as to close the opening of the package body. According to this configuration, it is possible to suppress a decrease in the detection accuracy of the magnetoresistance effect element as compared with a case where the sealing member fills the resin of the package body so as to close the opening. That is, the detection of the magnetoresistance effect element The accuracy is lowered by the influence of the stress acting on the magnetoresistance effect element and the influence of the humidity. However, when the sealing member is filled with the resin of the package body, there is a possibility that the detection accuracy of the magnetoresistance effect element is affected by the resin. The effect of the stress acting on the magnetoresistance effect element and the effect of the resin absorbing moisture. On the other hand, if the sealing member is a transparent glass cover that is fixed to the package body so as to close the opening, such a problem does not occur. Therefore, it is possible to suppress a decrease in the detection accuracy of the magnetoresistance effect element. Further, when the sealing member is a transparent glass cover that is fixed to the package body so as to close the opening, for example, when the cover is fixed to the package body, it is possible to confirm whether or not the cover is securely attached and fixed to the package. Ontology. Therefore, the element substrate can be reliably sealed by the cover.

In the present invention, it is preferable that the mark is formed at two portions on the first imaginary line passing through the center of the magnetic induction region of the magnetoresistance effect element and the first imaginary passing through the center of the magnetic induction region when viewed from the thickness direction of the element substrate The total of the two parts of the second imaginary line different in the line is four parts. According to this configuration, the center of the magnetic induction region can be detected based on the marks formed on the four portions. Further, according to this configuration, the mark can be formed on the element substrate at a position where the mark is easily formed, compared with the case where the mark is formed at one portion of the center of the magnetic induction region. Therefore, the mark can be easily formed on the element substrate. Further, in this configuration, when the magnetic sensor is attached to the mounting member, the direction of rotation of the magnetic sensor centered on the center of the magnetic sensing region when viewed from the thickness direction of the element substrate can be adjusted.

In the present invention, the mark may be formed at the center of the magnetic induction region of the magnetoresistance effect element when viewed from the thickness direction of the element substrate. In this case, the formation portion of the mark can be set to a minimum.

The magnetic sensor of the present invention can be applied to a motor having: a rotor having a rotating shaft; a stator; a motor housing accommodating the stator; a sensing magnet fixed to the shaft end of the rotating shaft; and a sensor substrate , equipped with a magnetic sensor; and as a mounting component A substrate holder for fixing the sensor substrate and being fixed to the motor housing. In this case, the magnetic sensor is disposed to face the sensing magnet such that the axial direction of the rotating shaft coincides with the thickness direction of the element substrate. In the motor, when the sensor substrate on which the magnetic sensor is mounted is mounted on the substrate holder, the magnetoresistive element can be aligned with respect to the substrate holder while checking the alignment mark. Therefore, it is possible to accurately mount the magnetoresistance effect element to the substrate holder. As a result, by accurately attaching the substrate holder to the motor casing, it is possible to reduce the amount of shift of the center of the sensing magnet and the center of the magnetic induction film of the magnetoresistance effect element when viewed from the axial direction of the rotating shaft.

In the present invention, it is preferable that a circular reference which is a positioning reference of the substrate holder in the radial direction with respect to the motor case is formed on the outer peripheral side in the radial direction of the rotation axis of the substrate holder when viewed in the axial direction. The plane or a plurality of arc-shaped reference planes, the center of curvature of the reference plane coincides with the center of the magnetic induction region when viewed from the axial direction. According to this configuration, the magnetoresistance effect element can be accurately mounted to the motor casing in the radial direction of the rotating shaft. Therefore, it is possible to effectively reduce the amount of shift of the center of the sensing magnet and the center of the magnetic sensing region of the magnetoresistive effect element when viewed from the axial direction of the rotating shaft.

In the present invention, it is preferable that a plurality of pins projecting toward the sensor substrate in the axial direction are formed in the substrate holder, and a through hole through which the pin is inserted is formed in the sensor substrate, and the peripheral surface of the pin is penetrated A gap for adjusting the position of the magnetoresistance effect element relative to the substrate holder is formed between the inner peripheral surfaces of the holes. According to this configuration, when the sensor substrate in which the magnetic sensor is mounted is mounted on the substrate holder, the sensor substrate can be adjusted relative to the substrate holder while the pin has been inserted into the through hole. The installation location. Therefore, when the sensor substrate is mounted on the substrate holder while the mounting position of the sensor substrate with respect to the substrate holder is adjusted, the sensor substrate does not have a large offset with respect to the substrate holder. As a result, the mounting operation of mounting the sensor substrate to the substrate holder can be easily performed.

In the present invention, it is preferable that the pin protrudes from the front side of the pin to the side of the sensor substrate. The method is inserted through the through hole, and the adhesive is applied in such a manner that the front end side of the pin protruding from the sensor substrate and one surface of the sensor substrate are applied. According to this configuration, since the subsequent operation can be performed while confirming the application of the adhesive, for example, it is possible to easily perform the subsequent operation as compared with the case where the adhesive flows into the other surface of the sensor substrate and the substrate holder. . Further, according to this configuration, the sensor substrate and the substrate holder can be temporarily fixed by the adhesive after the alignment of the magnetoresistance effect element with respect to the substrate holder while checking the alignment mark.

As described above, in the magnetic sensor of the present invention, when the sensing magnet is fixed to the motor of the shaft end of the rotating shaft, the center of the sensing magnet when viewed from the axial direction of the rotating shaft can be reduced. The offset from the center of the magneto-sensitive film of the magnetoresistance effect element. Further, in the motor of the present invention, it is possible to reduce the amount of shift between the center of the sensing magnet and the center of the magnetic resonance film of the magnetoresistance effect element when viewed from the axial direction of the rotating shaft.

1‧‧‧Motor

2‧‧‧Rotary axis

3‧‧‧Motor housing

4‧‧‧Testing agency

6‧‧‧Shell body

7, 8‧‧ ‧ cover parts

8a‧‧‧through hole

8b‧‧‧ datum

10‧‧‧Sensor magnet

10a‧‧‧Magnetic piece

11‧‧‧Magnetic sensor

12‧‧‧ housing

13‧‧‧Sensor substrate

13a‧‧‧slit

13b‧‧‧through hole

13c‧‧‧Gap section

14‧‧‧Substrate holder (mounting parts)

14a‧‧‧ Tube

14b‧‧‧Protruding

14c, 14d‧‧‧ convex

14e‧‧ sales

14f‧‧ ‧ step surface

14g‧‧‧through hole

14h‧‧‧outer surface (reference surface)

15‧‧‧Connector

18, 20‧‧‧ screws

19‧‧‧Adhesive

23‧‧‧MR components (magnetoresistive effect elements)

24‧‧‧ element substrate

25‧‧‧Package body

26‧‧‧ glass cover (sealing parts, cover)

29‧‧‧Resistance film for temperature monitoring

30‧‧‧Resistance film for heating

31, 32‧‧‧A phase (SIN) magnetic induction film

33, 34‧‧‧B phase (COS) magnetic induction film

36‧‧‧Magnetic sensing area

-A, +A, -B, +B‧‧‧ output terminals

C1‧‧‧Center of curvature of the outer perimeter (center of curvature of the reference plane)

C2‧‧‧The center of the magnetic sensing area

GNDA, GNDB‧‧‧ Ground Terminal

L1, L11‧‧‧ first imaginary line

L2, L12‧‧‧ second imaginary line

M1, M11‧‧‧ mark

VccA, VccB, VccH, VccS‧‧‧ power terminals

Fig. 1(A) is a perspective view of a motor according to an embodiment of the present invention, and Fig. 1(B) is a perspective view showing a state in which the casing is removed from the motor shown in Fig. 1(A).

Figure 2 is a perspective view of the cover member shown in Figure 1.

Fig. 3 is a perspective view of a sensing magnet and a magnetic sensor fixed to the opposite side end of the output shaft of the rotating shaft shown in Fig. 1(B).

4 is a perspective view of the detecting mechanism shown in FIG. 1.

Fig. 5 is an exploded perspective view of the detecting mechanism shown in Fig. 4.

Fig. 6 is a plan view showing the magnetic sensor and the sensor substrate shown in Fig. 1 from the output side.

Fig. 7 is a plan view showing the substrate holder shown in Fig. 1 from the output side.

Figure 8 is a cross-sectional view of the sensor substrate and the subsequent portion of the pin shown in Figure 4.

Fig. 9 is a perspective view showing the magnetic sensor shown in Fig. 3 from the output side.

Fig. 10 is a plan view showing an element substrate housed in the package body shown in Fig. 9.

Fig. 11 is a view for explaining a mounting method when the sensor substrate shown in Fig. 5 is mounted on a substrate holder.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(The overall composition of the motor)

Fig. 1(A) is a perspective view of a motor 1 according to an embodiment of the present invention, and Fig. 1(B) is a perspective view showing a state in which the casing 12 is removed from the motor 1 shown in Fig. 1(A). Fig. 2 is a perspective view of the cover member 8 shown in Fig. 1. 3 is a perspective view of the sensing magnet 10 and the magnetic sensor 11 fixed to the opposite side end of the output shaft 2 of the rotating shaft 2 shown in FIG. 1(B).

The motor 1 of the present embodiment is an inner rotor type motor. The motor 1 includes a stator (not shown) formed in a substantially cylindrical shape, a rotor having a rotating shaft 2 and disposed on an inner peripheral side of the stator, and a motor housing 3 accommodating the stator. One of the stator or the rotor has a driving magnet (not shown), and the other of the stator or the rotor has a driving coil (not shown). In the present embodiment, the rotor has a driving magnet, and the stator has a driving coil. Further, the motor 1 has a detecting mechanism 4 for detecting the rotational position of the rotor.

In the following description, the radial direction of the rotating shaft 2 (ie, the radial direction of the rotor) is "radial direction", and the circumferential direction of the rotating shaft 2 (ie, the circumferential direction of the rotor) is "circumferential direction" to rotate The axial direction of the shaft 2 (i.e., the axial direction of the rotor) is "axial". Further, the output side of the rotating shaft 2 in the axial direction (the Z1 direction side in Fig. 1 and the like) is the "front" side, and the opposite side of the output of the rotating shaft 2 in the axial direction (the side in the Z2 direction of Fig. 1 and the like) is "after "side.

As shown in Fig. 1, the motor housing 3 has a cylindrical casing body 6 constituting a side surface of the motor casing 3, a cover member 7 fixed to the front end of the casing body 6, and a cover member 8 fixed to the casing. The rear end of the body 6. As shown in Fig. 2, a through hole 8a penetrating in the axial direction is formed at the center of the cover member 8 in the radial direction. The through hole 8a is formed in a circular hole shape with a step. The inner peripheral surface of the end side portion after the through hole 8a serves as a reference surface 8b for the radial direction The substrate holder 14 which will be described later, which constitutes the detecting means 4, is positioned. The reference surface 8b is formed in a cylindrical shape. That is, the shape of the reference surface 8b is formed in a circular shape when viewed in the axial direction. A bearing (not shown) that rotatably supports the rotating shaft 2 is attached to the end side portion of the through hole 8a, and the center of the reference surface 8b coincides with the center of the rotating shaft 2 when viewed in the axial direction. In addition, in FIG. 1, the illustration of the through-hole 8a is abbreviate|omitted.

The detecting mechanism 4 is a magnetic rotary encoder. As shown in FIG. 3, the detecting mechanism 4 has a sensing magnet 10 and a magnetic sensor 11 disposed opposite to the sensing magnet 10. The detecting mechanism 4 is disposed at a position closer to the rear side than the rotor and the stator. As shown in FIG. 1(A), the detecting mechanism 4 is covered by a casing 12 fixed to the cover member 8. The magnetic sensor 11 is mounted on the sensor substrate 13. The sensor substrate 13 is fixed to the substrate holder 14 . The substrate holder 14 is fixed to the cover member 8. The substrate holder 14 of the present embodiment is a mounting member to which the magnetic sensor 11 is attached, and the magnetic sensor 11 is attached to the substrate holder 14 via the sensor substrate 13. The specific configuration of the magnetic sensor 11, the sensor substrate 13, and the substrate holder 14 will be described later.

The sensing magnet 10 is formed as a disk-shaped permanent magnet. The sensing magnet 10 is fixed to the shaft end of the rotating shaft 2 (specifically, the rear end of the rotating shaft 2) directly or via a specific magnet holder (not shown), and the surface of the magnet 10 is sensed with a specific gap. It faces the magnetic sensor 11. Further, the sensing magnet 10 is fixed to the rotating shaft 2 such that the center of the sensing magnet 10 coincides with the center of the rotating shaft 2 when viewed in the axial direction.

The surface of the sensing magnet 10 facing the magnetic sensor 11 (that is, the surface of the sensing magnet 10) is magnetized to the N pole and the S pole in a circumferential direction. That is, the opposing faces of the sensing magnet 10 and the magnetic sensor 11 are magnetized into two poles in the circumferential direction. The sensing magnet 10 of the present embodiment is composed of two magnet pieces 10a formed in a semicircular plate shape, and one of the two magnet pieces 10a is magnetized to an N pole, and the other surface of the other magnet piece 10a is Magnetization is S pole. Further, the sensing magnet 10 may be composed of one magnet piece formed in a disk shape.

(Configuration of sensor substrate and substrate holder)

4 is a perspective view of the detecting mechanism 4 shown in FIG. 1. Fig. 5 is an exploded perspective view of the detecting mechanism 4 shown in Fig. 4. Fig. 6 is a plan view showing the magnetic sensor 11 and the sensor substrate 13 shown in Fig. 1 from the output side. Fig. 7 is a plan view showing the substrate holder 14 shown in Fig. 1 from the output side. Figure 8 is a cross-sectional view of the subsequent portion of the sensor substrate 13 and the pin 14e shown in Figure 4 .

The sensor substrate 13 is a printed wiring board formed in a flat shape. The sensor substrate 13 is disposed such that the thickness direction of the sensor substrate 13 coincides with the axial direction. The magnetic sensor 11 is mounted at the center of the front surface of the sensor substrate 13. Two slits 13a are formed in the sensor substrate 13 so as to surround the magnetic sensor 11. Further, the sensor substrate 13 is formed with a through hole 13b penetrating in the axial direction (that is, in the thickness direction of the sensor substrate 13) and a notch portion cut from the outer peripheral end of the detector substrate 13 toward the center side. 13c.

The slit 13a is formed to penetrate the sensor substrate 13 in the axial direction, and is formed in a substantially L shape. The through hole 13b is formed in a circular hole shape and formed in the vicinity of the outer peripheral end of the sensor substrate 13. Further, the through hole 13b is formed in three places. The three through holes 13b are formed at positions separated from each other in such a manner that the imaginary lines connected by the three through holes 13b form a substantially right-angled triangle when viewed from the axial direction. The notch portion 13c is formed in a U shape. The notch portion 13c is formed at two locations so as to sandwich the magnetic sensor 13. In addition, a connector 15 is mounted on the surface behind the sensor substrate 13.

The substrate holder 14 is formed of a resin material. The substrate holder 14 has a cylindrical portion 14a formed in a tubular shape, and three protruding portions 14b projecting outward in the radial direction from the front end side of the outer peripheral surface of the cylindrical portion 14a. The inner peripheral surface of the tubular portion 14a has a cylindrical surface. That is, the inner peripheral surface of the tubular portion 14a is circular when viewed from the axial direction. The rear end surface of the tubular portion 14a is formed in a planar shape orthogonal to the axial direction. The sensor substrate 13 is fixed to the rear end side of the cylindrical portion 14a.

The rear end surface of the tubular portion 14a is formed with two cylindrical convex portions 14c projecting toward the rear side, and a cylindrical convex portion 14d protruding toward the rear side. Front end of convex portion 14c, 14d The surface is formed in a planar shape orthogonal to the axial direction. The front surface of the sensor substrate 13 is in contact with the front end faces of the convex portions 14c and 14d. A screw hole is formed in the inner circumferential surface of the convex portion 14c. At the screw hole, a screw 18 for fixing the sensor substrate 13 to the substrate holder 14 is engaged. The screw 18 is disposed to pass through the notch portion 13c of the sensor substrate 13.

Further, three pins 14e are formed on the end surface of the cylindrical portion 14a, and the pin 14e protrudes toward the sensor substrate 13 in the axial direction (that is, protrudes toward the rear side). The pin 14e is formed in a columnar shape with a step, and a stepped surface 14f having an annular shape orthogonal to the axial direction is formed in the pin 14e. The three pins 14e are respectively inserted into the three through holes 13b of the sensor substrate 13. Specifically, the front surface of the sensor substrate 13 is in contact with the step surface 14f, and the front end side of the pin 14e is inserted into the through hole 13b. Further, the front end side of the pin 14e protrudes further toward the rear side than the rear surface of the sensor substrate 13.

As shown in FIG. 8, a gap is formed between the outer peripheral surface of the end side before the pin 14e inserted into the through hole 13b and the inner peripheral surface of the through hole 13b. Specifically, a gap for adjusting the fixed position of the sensor substrate 13 with respect to the substrate holder 14 is formed in the outer peripheral surface of the front end side of the pin 14e and the through hole 13b in the direction orthogonal to the axial direction. Between the weeks. More specifically, a gap for adjusting the position of the magnetoresistance effect element 23 to be described later of the magnetic sensor 11 mounted on the sensor substrate 13 in the direction orthogonal to the axial direction is formed at the front end of the pin 14e. The outer peripheral surface of the side and the inner peripheral surface of the through hole 13b.

In the present embodiment, the sensor substrate 13 is temporarily fixed to the substrate holder 14 by the adhesive 19 before being fixed to the substrate holder 14 by the screws 18. As shown in FIG. 8, the adhesive 19 is applied in such a manner as to extend over the front end side of the pin 14e and the rear surface of the sensor substrate 13 which protrude further toward the rear side than the rear surface of the sensor substrate 13. The adhesive 19 is, for example, an ultraviolet (UV) curable adhesive.

When viewed from the axial direction, the three protruding portions 14b are disposed at a pitch of approximately 120 degrees with respect to the center of the inner peripheral surface of the tubular portion 14a. A through hole 14g is formed in the protruding portion 14b, and the through hole 14g is provided with a screw 20 (refer to FIG. 4) for fixing the substrate holder 14 to the cover member 8. Wear inserts. Further, a screw hole for engaging the screw 20 is formed in the cover member 8, but in FIG. 2, the illustration of the screw hole is omitted.

The shape of the outer peripheral surface 14h of the protruding portion 14b when viewed from the axial direction is formed into a curved shape having an arc shape. As shown in Fig. 7, the center of curvature C1 of the outer peripheral surface 14h of the three protruding portions 14b coincides when viewed in the axial direction. In the present embodiment, the outer peripheral surface 14h of the protruding portion 14b serves as a reference surface for the positioning of the substrate holder 14 in the radial direction with respect to the cover member 8, and when the substrate holder 14 is fixed to the cover member 8, the cover member is used. The reference surface 8b of 8 and the outer peripheral surface 14h of the protruding portion 14b determine the position of the substrate holder 14 in the radial direction with respect to the cover member 8. In other words, in the present embodiment, a plurality of arcs which are the positioning reference of the substrate holder 14 in the radial direction with respect to the motor housing 3 are formed on the outer peripheral side in the radial direction of the substrate holder 14 when viewed in the axial direction. Shaped datum.

In a state where the substrate holder 14 is fixed to the cover member 8, the center of curvature C1 of the outer peripheral surface 14h of the three protruding portions 14b coincides with the center of the reference surface 8b when viewed in the axial direction. As described above, since the center of the reference surface 8b coincides with the center of the rotating shaft 2 when viewed from the axial direction, the center of curvature C1 and the rotating shaft 2 of the outer peripheral surface 14h of the three protruding portions 14b are viewed from the axial direction. The center is consistent. Further, when viewed in the axial direction, the center of curvature C1 of the outer peripheral surface 14h of the three protruding portions 14b coincides with the center of the inner peripheral surface of the tubular portion 14a.

(Composition of magnetic sensor)

Fig. 9 is a perspective view showing the magnetic sensor 11 shown in Fig. 3 from the output side. FIG. 10 is a plan view of the element substrate 24 housed in the package body 25 shown in FIG.

The magnetic sensor 11 has: a magnetoresistive effect element 23 (hereinafter referred to as "MR element 23"); an element substrate 24 formed with an MR element 23; a box-shaped package body 25 accommodating the element substrate 24; and a seal The member 26 closes the opening of the package body 25 to seal the element substrate 24 (i.e., seal the MR element 23). The package body 25 is formed in a box shape having a rectangular parallelepiped shape on the front end side. The sealing member 26 of the present embodiment is a transparent glass cover (glass cover). Therefore, the sealing member 26 will hereinafter be referred to as a "glass cover 26".

The glass cover 26 is formed in a substantially rectangular flat plate shape. The cover glass 26 is fixed to the front end of the package body 25 so as to close the opening of the package body 25. Further, the glass cover 26 is fixed to the front end of the package body 25 by the subsequent step, and the package body 25 and the glass cover 26 form a sealed space for accommodating the element substrate 24. A gap is formed between the element substrate 24 housed in the package body 25 and the glass cover 26, and the element substrate 24 is not in contact with the glass cover 26. Since the glass cover 26 is transparent, when the magnetic sensor 11 is viewed from the front surface side, the front surface of the element substrate 24 accommodated in the package body 25 can be seen.

The element substrate 24 is formed into a rectangular flat printed wiring board. The element substrate 24 is disposed such that the thickness direction of the element substrate 24 coincides with the axial direction. The element substrate 24 is formed not only with the MR element 23 but also with the temperature monitoring resistive film 29 and the heating resistive film 30. The MR element 23, the temperature monitoring resistive film 29, and the heating resistive film 30 are formed on the front surface of the element substrate 24. The MR element 23, the temperature monitoring resistive film 29, and the heating resistive film 30 are covered with an insulating film.

The MR element 23 has phase A (SIN) magnetic induction films 31 and 32 and phase B (COS) magnetic induction films 33 and 34. The magnetic induction films 31 to 34 are formed at the center of the element substrate 24. In the present embodiment, as shown in Fig. 10, a circular magnetic induction region 36 is formed by the magnetic induction films 31 to 34. The phases of the A-phase magnetic induction films 31 and 32 are different from the phase of the B-phase magnetic induction films 33 and 34 by 90 degrees. That is, the A-phase magnetic induction films 31, 32 and the B-phase magnetic induction films 33, 34 have a phase difference of 90 degrees. Further, in the phase A, the phase of the magnetic induction film 31 is different from the phase of the magnetic induction film 32 by 180 degrees, and in the phase B, the phase of the magnetic induction film 33 is different from the phase of the magnetic induction film 34 by 180 degrees.

The magnetic induction films 31 and 32 constitute a bridge circuit, and one end of the bridge circuit is connected to the power supply terminal VccA, and the other end is connected to the ground terminal GNDA. Further, the position of the magnetic induction film 31 is connected to the output terminal +A, and the position of the magnetic induction film 32 is connected to the output terminal -A. Similarly, the magnetic induction films 33 and 34 constitute a bridge circuit, and one end of the bridge circuit is connected to the power supply terminal VccB, and the other end is connected to the ground terminal GNDB. Also, the magnetic induction film 33 The midpoint position is connected to the output terminal +B, and the dot position of the magnetic induction film 34 is connected to the output terminal -B.

The heating resistive film 30 is formed in a rectangular frame shape. Further, the heating resistive film 30 is formed along the end surface of the element substrate 24, and is disposed to surround the magnetic induction region 36. The heating resistive film 30 is connected to the power supply terminal VccH and to the ground terminal GNDA. The temperature monitoring resistive film 29 is disposed between the magnetic induction region 36 and the heating resistive film 30. The temperature monitoring resistive film 29 is connected to the power supply terminal VccS and to the ground terminal GNDB. In the present embodiment, temperature control for controlling the supply of power to the heating resistor film 30 is performed based on the change in resistance of the temperature monitoring resistive film 29.

Further, a mark M1 for aligning the MR element 23 with respect to the substrate holder 14 is formed on the element substrate 24. Specifically, a mark M1 for aligning the MR element 23 with respect to the substrate holder 14 in the direction orthogonal to the axial direction (radial direction) is formed on the element substrate 24. The mark M1 is formed on the front surface of the element substrate 24. As shown in FIG. 10, when viewed from the thickness direction of the element substrate 24, the imaginary line passing through the center C2 of the magnetic induction region 36 is the imaginary line L1, and the imaginary line passing through the center C2 of the magnetic induction region 36 and different from the imaginary line L1. When the imaginary line L2 is viewed from the thickness direction of the element substrate 24, the mark M1 is formed in two places on the imaginary line L1 and the total of the two parts on the imaginary line L2. In the present embodiment, the imaginary lines L1, L2 are orthogonal to each other and parallel to the end faces of the element substrate 24. Further, the marks M1 of the two portions formed on the imaginary line L1 are formed so as to sandwich the magnetic induction region 36, and the marks M1 of the two portions formed on the imaginary line L2 are formed to sandwich the magnetic induction region 36. The imaginary line L1 of the present embodiment is the first imaginary line, and the imaginary line L2 is the second imaginary line.

(Method of mounting the sensor substrate to the substrate holder)

FIG. 11 is a view for explaining a mounting method when the sensor substrate 13 shown in FIG. 5 is mounted on the substrate holder 14.

Mounting the sensor substrate 13 in a state in which the magnetic sensor 11 is mounted on the substrate holding At the time of the frame 14, first, the pin 14e of the substrate holder 14 is inserted into the through hole 13b of the sensor substrate 13 in a state in which the magnetic sensor 11 is mounted. Specifically, the pin 14e is inserted into the through hole 13b until the front surface of the sensor substrate 13 abuts against the step surface 14f of the pin 14e. Thereafter, by the image processing, the center of curvature C1 of the outer peripheral surface 14h of the three protruding portions 14b when viewed from the axial direction is calculated, and the magnetic induction when viewed from the axial direction is calculated by image processing using four marks M1. Center C2 of area 36.

Thereafter, as shown in FIG. 11, the center of curvature C1 of the outer peripheral surface 14h coincides with the center C2 of the magnetic induction region 36 as viewed in the axial direction, so that the sensor substrate 13 is opposed to the plane orthogonal to the axial direction. The substrate holder 14 is active. When viewed from the axial direction, if the center of curvature C1 of the outer peripheral surface 14h coincides with the center C2 of the magnetic sensing region 36, the front end side of the pin 14e protruding from the rear surface of the sensor substrate 13 and the sensor substrate The adhesive 19 is applied in a manner of 13 after the surface, thereby temporarily fixing the sensor substrate 13 to the substrate holder 14. Thereafter, the sensor substrate 13 is fixed to the substrate holder 14 by the screws 18.

In this way, since the sensor substrate 13 in the state in which the magnetic sensor 11 is mounted is mounted on the substrate holder 14, the sensor substrate 13 in the state in which the magnetic sensor 11 is mounted is mounted on the substrate. When the holder 14 is viewed from the axial direction, the center of curvature C1 of the outer peripheral surface 14h coincides with the center C2 of the magnetic induction region 36.

(Main effects of this embodiment)

As described above, in the present embodiment, the alignment mark M1 for aligning the MR element 23 with respect to the substrate holder 14 is formed on the surface of the element substrate 24 on which the MR element 23 is formed. Further, in the present embodiment, the glass cover 26 fixed to the package body 25 in which the element substrate 24 is housed is transparent, and when the magnetic sensor 11 is viewed from the front surface side, it can be seen and accommodated in the package body 25. The front surface of the component substrate 24. Therefore, in the present embodiment, as described above, when the sensor substrate 13 to which the magnetic sensor 11 is mounted is mounted on the substrate holder 14, the outer peripheral surface 14h can be viewed from the axial direction by the mark M1. The manner in which the center of curvature C1 coincides with the center C2 of the magnetic sensing region 36, The position of the MR element 23 relative to the substrate holder 14 is adjusted. Therefore, in the present embodiment, the MR element 23 can be accurately mounted on the substrate holder 14.

Further, in the present embodiment, when the sensing magnet 10 is viewed from the axial direction, the center of curvature C1 of the outer peripheral surface 14h of the protruding portion 14b coincides with the center of the rotating shaft 2, and the center of the magnet 10 and the rotating shaft 2 are sensed. The center is fixed to the rotating shaft 2 in a consistent manner. As described above, in the present embodiment, it is possible to reduce the amount of shift between the center of the sensing magnet 10 and the center C2 of the magnetic sensing region 36 when viewed from the axial direction.

In the present embodiment, the opening on the front end side of the package body 25 is closed by the cover glass 26, and a gap is formed between the element substrate 24 accommodated in the package body 25 and the cover glass 26. Therefore, in the present embodiment, it is possible to suppress a decrease in the detection accuracy of the MR element 23 as compared with a case where the sealing member of the closing element substrate 24 is a resin filled in the package body 25. In other words, the detection accuracy of the MR element 23 is lowered by the influence of the stress acting on the MR element 23 and the influence of the humidity. However, when the sealing member is filled with the resin of the package body 25, the resin acts on the resin. The influence of the stress of the MR element 23 and the influence of the moisture absorbed by the resin may reduce the detection accuracy of the MR element 23. On the other hand, in the present embodiment, since a gap is formed between the element substrate 24 accommodated in the package main body 25 and the cover glass 26, such a problem does not occur. Therefore, in the present embodiment, it is possible to suppress a decrease in the detection accuracy of the MR element 23.

Further, in the present embodiment, since the opening on the front end side of the package main body 25 is closed by the transparent glass cover 26, when the glass cover 26 is subsequently fixed to the package main body 25, the glass cover 26 can be confirmed. Whether it is reliably followed and fixed to the package body 25. Therefore, the element substrate 24 can be surely sealed by the glass cover 26.

In the present embodiment, between the outer peripheral surface of the front end side of the pin 14e of the substrate holder 14 and the inner peripheral surface of the through hole 13b of the sensor substrate 13, an adjustment is made in a direction orthogonal to the axial direction. The gap of the position of the MR element 23. Therefore, in the present embodiment, as described above, the sensor substrate 13 in a state in which the magnetic sensor 11 is mounted is mounted on the substrate. In the case of the holder 14, the mounting position of the sensor substrate 13 with respect to the substrate holder 14 can be adjusted in a state where the pin 14e has been inserted into the through hole 13b. Therefore, in the present embodiment, while the sensor substrate 13 is mounted on the substrate holder 14 while the mounting position of the sensor substrate 13 with respect to the substrate holder 14 is adjusted, the sensor substrate 13 is held relative to the substrate. The frame 14 does not create a large offset. As a result, in the present embodiment, the mounting operation of the sensor substrate 13 to the substrate holder 14 can be easily performed.

In the present embodiment, the adhesive 19 is applied so as to extend over the front end side of the pin 14e and the rear surface of the sensor substrate 13 which protrude further toward the rear side than the rear surface of the sensor substrate 13. Therefore, in the present embodiment, the subsequent operation can be performed while confirming the applied adhesive 19. Therefore, for example, the situation between the end surface after the adhesive agent flows into the cylindrical portion 14a of the substrate holder 14 and the front surface of the sensor substrate 13, and the end face and the sensing after the adhesive flows into the step surface 14f of the substrate holder 14 The subsequent operation can be easily performed as compared with the case between the front surfaces of the substrate 13.

(Other embodiments)

The embodiment described above is an example of a preferred embodiment of the present invention, and the present invention is not limited thereto, and various modifications can be made without departing from the spirit and scope of the invention.

In the above embodiment, the imaginary lines L1, L2 passing through the center C2 of the magnetic induction region 36 are orthogonal to each other and parallel to the end faces of the element substrate 24. In addition, for example, as shown in FIG. 10, the imaginary lines L11 and L12 passing through the center C2 of the magnetic induction region 36 may substantially coincide with the diagonal lines of the heating resistive film 30 formed in a rectangular frame shape. In this case, a mark M11 for aligning the MR element 23 with respect to the substrate holder 14 is formed at four locations on the imaginary line L11 and the two locations on the imaginary line L12. Further, in this case, the imaginary line L11 is the first imaginary line, and the imaginary line L12 is the second imaginary line. Further, the mark for aligning the MR element 23 with respect to the substrate holder 14 may be formed in one portion, two portions, or three portions, or may be formed in five or more portions. For example, when viewed from the thickness direction of the element substrate 24, the mark is also It can be formed at one portion of the center C2 of the magnetic induction region 36. In this case, the formation portion of the mark can be provided to a minimum.

In addition, the case where the mark M1 is formed in four places on the imaginary line L1 and the two parts on the imaginary line L2, and the two parts on the imaginary line L11 and the two parts on the imaginary line L12 When the mark M11 is formed in four places in total, the marks M1 and M11 can be formed on the element substrate 24 to form the marks M1 and M11 as compared with the case where the mark is formed in one portion of the center C2 of the magnetic induction region 36. . Therefore, the marks M1 and M11 can be easily formed on the element substrate 24.

In the above-described embodiment, when viewed in the axial direction, a plurality of arc-shaped reference faces (outer peripheral faces 14h) are formed on the outer peripheral side in the radial direction of the substrate holder 14, and the reference faces are the substrate holders 14 opposed to each other. Positioning reference of the motor housing 3 in the radial direction. In addition, for example, when viewed from the axial direction, a circular reference surface which is a reference position for the radial direction of the substrate holder 14 with respect to the motor housing can be formed on the outer circumferential side of the substrate holder 14 in the radial direction. A plurality of convex portions which are positioning references of the substrate holder 14 with respect to the motor housing 3 in the radial direction can be formed on the outer peripheral side of the substrate holder 14. Further, in the above embodiment, the sealing member 26 is a transparent glass cover (glass cover), but the sealing member 26 may be a transparent resin filled in the package body 25. Further, in the above-described embodiment, the pin 14e is formed in the substrate holder 14, and the through hole 13b through which the pin 14e is inserted is formed in the sensor substrate 13, but the pin 14e and the through hole 13b may not be formed. Further, in the above-described embodiment, the adhesive 19 is an ultraviolet curable adhesive, but the adhesive 19 may be between the end surface after flowing into the step surface 14f of the substrate holder 14 and the front surface of the sensor substrate 13, and An instantaneous adhesive agent flows between the end surface of the convex portion 14c, 14d of the substrate holder 14 and the front surface of the sensor substrate 13.

11‧‧‧Magnetic sensor

13‧‧‧Sensor substrate

13a‧‧‧slit

13b‧‧‧through hole

13c‧‧‧Gap section

14‧‧‧Substrate holder (mounting parts)

14a‧‧‧ Tube

14b‧‧‧Protruding

14g‧‧‧through hole

14h‧‧‧outer surface (reference surface)

24‧‧‧ element substrate

25‧‧‧Package body

26‧‧‧ glass cover (sealing parts, cover)

36‧‧‧Magnetic sensing area

C1‧‧‧Center of curvature of the outer perimeter (center of curvature of the reference plane)

C2‧‧‧The center of the magnetic sensing area

M1‧‧‧ mark

Claims (8)

A magnetic sensor having a magnetoresistance effect element, comprising: an element substrate on which the magnetoresistive effect element is formed; a box-shaped package body accommodating the element substrate; and a transparent sealing member, The element substrate is sealed by an opening formed in the package body to seal the element substrate, and a position alignment mark is formed on the element substrate, and the alignment mark is used to mount the magnetoresistive element with respect to the above The mounting components of the magnetic sensor are aligned. The magnetic sensor of claim 1, wherein the sealing member is fixed to a transparent glass cover of the package body such that the opening is closed. The magnetic sensor of claim 1 or 2, wherein the mark is formed at two locations on the first imaginary line passing through the center of the magnetic sensing region of the magnetoresistance effect element and is observed when viewed from a thickness direction of the element substrate The total of the two locations on the second imaginary line different from the first imaginary line at the center of the magnetic sensing region is four locations. The magnetic sensor of claim 1 or 2, wherein the mark is formed at a center of a magnetic induction region of the magnetoresistive element when viewed from a thickness direction of the element substrate. A motor comprising: a rotor having a rotating shaft; a stator; a motor housing accommodating the stator; a sensing magnet fixed to an axial end of the rotating shaft; and a magnetic sensor as the request item 2 a magnetic sensor, which is disposed opposite to the sensing magnet in such a manner that an axial direction of the rotating shaft coincides with a thickness direction of the element substrate; a sensor substrate equipped with the magnetic sensor; and the mounting member a substrate holder for fixing the sensor substrate and fixing It is set in the above motor housing. The motor according to claim 5, wherein the substrate holder is formed on the outer peripheral side in the radial direction of the rotating shaft of the substrate holder in the radial direction with respect to the motor housing. The circular reference plane or the plurality of arc-shaped reference planes of the positioning reference, when viewed in the axial direction, the center of curvature of the reference plane coincides with the center of the magnetic sensing region of the magnetoresistance effect element. The motor of claim 5 or 6, wherein the substrate holder has a plurality of pins protruding in the axial direction toward the sensor substrate, and a through hole through which the pin is inserted is formed in the sensor substrate A gap for adjusting a position of the magnetoresistance effect element relative to the substrate holder is formed between a peripheral surface of the pin and an inner circumferential surface of the through hole. The motor of claim 7, wherein the pin is inserted into the through hole so as to protrude from one surface of the sensor substrate at a front end side of the pin so as to extend over the pin protruding from the sensor substrate An adhesive is applied to the front end side and one surface of the above sensor substrate.