Magnetic sensor device

Abstract

To enable easy installation of a magnetic sensor on a substrate along with other electrical and electronic components.SOLUTION: A magnetic sensor device 3 includes a sensor unit 4 and substrate-side connectors 24, 25. The sensor unit 4 comprises a magnetic sensor, a yoke, and a casing 19. The magnetic sensor includes: a magnetic wire material exhibiting a large Barkhausen effect; a bobbin in which the magnetic wire material is arranged; a coil formed by winding a wire around the bobbin; and a sensor-side connector provided on the left end of the bobbin and a sensor-side connector provided on the right end of the bobbin. The magnetic sensor device 3 is installed on a substrate 35 by mounting the substrate-side connectors 24, 25 onto the substrate 35 and then connecting the sensor unit 4 to the substrate-side connectors 24, 25.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a magnetic sensor device utilizing the large Barkhausen effect. [Background technology]

[0002] A magnetic sensor utilizing the Great Barkhausen effect includes a magnetic wire that exhibits the Great Barkhausen effect, a bobbin in which the magnetic wire is disposed, a coil formed by winding an electric wire around the bobbin, and two terminals for connecting the coil to an external detection circuit. The two terminals are fixed to both ends of the bobbin. One of the two terminals is connected to one end of the electric wire that forms the coil, and the other end of the electric wire that forms the coil is connected to the other terminal. The magnetic sensor is fixed on a substrate, for example, by soldering the respective ends of the two terminals to a conductive portion provided on the substrate. An example of such a magnetic sensor is described in International Publication No. 2016 / 021074 (Patent Document 1).

[0003] For example, as described in International Publication No. 2016 / 021074, when a magnetic sensor is used to detect the rotation of a rotating shaft, a magnet is fixed to the outer periphery of the rotating shaft so that a rotating magnetic field is formed on the outer periphery of the rotating shaft when the rotating shaft rotates. In addition, a substrate is provided on the outer periphery of the rotating shaft so as not to come into contact with either the rotating shaft or the magnet, and multiple magnetic sensors are provided on the substrate. In addition, the multiple magnetic sensors are disposed near the rotation orbit of the magnet and at different positions in the rotation direction of the magnet. In this way, the rotating magnetic field formed by the rotation of the rotating shaft can be detected by the multiple magnetic sensors, and the amount of rotation and the direction of rotation of the rotating shaft can be detected based on the detection signal output from the coil of each magnetic sensor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2016 / 021074 Summary of the Invention [Problem to be solved by the invention]

[0005] In addition to the magnetic sensor, a plurality of electric and electronic components are also provided on the substrate on which the magnetic sensor is provided. These electric and electronic components may be various components such as resistors, capacitors, diodes, transistors, and integrated circuits. However, due to the demand for reducing the substrate area, small surface mount components (chip components) are used as these electric and electronic components. Meanwhile, as described in International Publication No. 2016 / 021074, conventional magnetic sensors are insertion mount components (dip components).

[0006] When mounting a conventional magnetic sensor on a substrate together with other electric and electronic components, the following problems arise.

[0007] For example, by changing the shape of each terminal of a conventional magnetic sensor, it is possible to make the conventional magnetic sensor surface mountable. However, the magnetic sensor has a larger volume and therefore a larger heat capacity than small surface-mounted electric and electronic components. When multiple components are surface-mounted on a board by the reflow soldering method, if there is a large difference in heat capacity between the multiple components, the settings or measures for heating, insulation, heat dissipation, etc. for proper soldering become complicated. Therefore, it is not easy to surface-mount the magnetic sensor and other electric and electronic components on the board at the same time by the reflow soldering method. As a result, a process for mounting the magnetic sensor on the board must be set up separately from the process for surface-mounting other electric and electronic components on the board, and the man-hours for soldering the magnetic sensor and other electric and electronic components to the board increase.

[0008] In addition, because magnetic sensors are larger than small surface-mounted electric and electronic components, when a magnetic sensor is mounted on a board, the ratio of the area occupied by the magnetic sensor to the board area becomes large. As a result, the space on the board for mounting other electric and electronic components becomes smaller, and the number of electric and electronic components that can be mounted on the board decreases.

[0009] The present invention has been made in consideration of problems such as those described above, and an object of the present invention is to provide a magnetic sensor device in which a magnetic sensor can be easily mounted on a substrate together with other electric and electronic components. [Means for solving the problem]

[0010] In order to solve the above problems, the magnetic sensor device of the present invention includes a magnetic sensor including a magnetic wire that exhibits a large Barkhausen effect, a bobbin in which the magnetic wire is disposed, a coil formed by winding an electric wire around the bobbin, a first connector provided at one end of the bobbin, and a second connector provided at the other end of the bobbin, a third connector detachably connected to the first connector, and a fourth connector detachably connected to the second connector, the first connector having a first fitting portion and a coil for winding the electric wire around the bobbin. the second connector has a second mating portion and a second terminal to which the other end of the electric wire is connected; the third connector has a third mating portion mated with the first mating portion and a third terminal that contacts the first terminal when the first mating portion is mated with the third mating portion; and the fourth connector has a fourth mating portion mated with the second mating portion and a fourth terminal that contacts the second terminal when the second mating portion is mated with the fourth mating portion.

[0011] In the magnetic sensor device of the present invention described above, the third connector and the fourth connector can be mounted on a substrate, for example, together with other electric and electronic components, and then the first connector and the second connector of the magnetic sensor can be connected, respectively, to the third connector and the fourth connector mounted on the substrate, thereby providing the magnetic sensor on the substrate.

[0012] The third connector and the fourth connector can be surface-mounted. The third connector and the fourth connector are smaller than the magnetic sensor and have a smaller heat capacity. Therefore, when the third connector and the fourth connector are surface-mounted on a board together with other electric and electronic components by reflow soldering, it is easier to set or take measures such as heating, insulation, and heat dissipation to properly perform soldering, compared with the case where the magnetic sensor is surface-mounted on a board together with other electric and electronic components by reflow soldering. Therefore, the third connector, the fourth connector, and other electric and electronic components can be easily surface-mounted on the board at once by reflow soldering. Therefore, the number of steps required for soldering can be reduced when providing the magnetic sensor and other electric and electronic components on the board.

[0013] In the magnetic sensor of the present invention, the third connector and the fourth connector are mounted, for example, at two locations on the mounting surface of the substrate, which are spaced apart from each other, and the first connector and the second connector of the magnetic sensor are connected to the third connector and the fourth connector, respectively, so that the magnetic sensor can be provided on the substrate. In this case, the magnetic sensor can be provided so as to bridge between the third connector and the fourth connector. By providing the magnetic sensor in this manner, a space in which other electric / electronic components can be mounted can be formed between the mounting surface of the substrate and an intermediate portion between one end of the magnetic sensor where the first connector is provided and the other end where the second connector is provided. By mounting other electric / electronic components in this space, the number of electric / electronic components that can be mounted on the substrate can be increased.

[0014] In the magnetic sensor device of the present invention described above, the coil is provided between one end and the other end of the bobbin, the first connector is provided under one end of the bobbin, the second connector is provided under the other end of the bobbin, the third connector is provided on the upper surface of the substrate so that the first fitting portion can be fitted into the third fitting portion from above the third fitting portion, and the fourth connector is provided on the upper surface of the substrate so that the second fitting portion can be fitted into the fourth fitting portion from above the fourth fitting portion, the third connector and the fourth connector are arranged apart from each other on the upper surface of the substrate, and in a state in which the first fitting portion is fitted into the third fitting portion from above the third fitting portion and the second fitting portion is fitted into the fourth fitting portion from above the fourth fitting portion, the magnetic wire and the bobbin extend parallel to the upper surface of the substrate, and a space is formed between the lower part of the outer circumferential surface of the coil and the upper surface of the substrate. In the magnetic sensor device of the present invention, the third connector and the fourth connector may each be surface-mounted on a substrate. In the magnetic sensor device of the present invention, a yoke for controlling the direction of the magnetic flux of an external magnetic field may be provided, and the yoke may be fixed to the magnetic sensor. In the magnetic sensor device of the present invention, a yoke for controlling the direction of the magnetic flux of an external magnetic field and a casing in which the magnetic sensor is housed may be provided, and the yoke may be fixed to the casing, in which case the yoke may be integrated with the casing by insert molding. Effect of the Invention

[0015] According to the present invention, the magnetic sensor can be easily provided on a substrate together with other electric and electronic components. [Brief description of the drawings]

[0016] [Figure 1] 1 is an explanatory diagram illustrating a rotation detection device including a magnetic sensor device according to an embodiment of the present invention. [Diagram 2]2 is a cross-sectional view of the rotation detector taken along line AA in FIG. 1, as viewed from the lower right in FIG. [Diagram 3] 1 is a perspective view showing a magnetic sensor device according to an embodiment of the present invention as viewed from the upper right front side. [Figure 4] 1A is a perspective view showing a sensor unit in a magnetic sensor device according to an embodiment of the present invention as viewed from the upper right rear, and FIG. 1B is a perspective view showing the sensor unit as viewed from the lower right front. [Diagram 5] 2 is an explanatory diagram showing a magnetic sensor, a yoke, and a casing of a sensor unit in the magnetic sensor device according to the embodiment of the present invention, viewed from the upper right front side. FIG. [Figure 6] 1 is a perspective view showing a state in which a magnetic sensor in a magnetic sensor device according to an embodiment of the present invention is viewed from the upper right front side. [Figure 7] 1A is a perspective view showing a bobbin in a magnetic sensor of a magnetic sensor device according to an embodiment of the present invention, as viewed from the front upper right, and FIG. 1B is a perspective view showing the bobbin as viewed from the rear lower right. [Figure 8] 8(A) is an external view showing the left end portion of a magnetic sensor in a magnetic sensor device according to an embodiment of the present invention as viewed from below, and FIG. 8(B) is a cross-sectional view showing the left end portion of the magnetic sensor as viewed from the left, cut along cutting line BB in FIG. 8(A). [Figure 9] 1 is a perspective view showing a yoke and a casing integrated by insert molding in a magnetic sensor device according to an embodiment of the present invention. [Figure 10] 5A to 5C are explanatory diagrams showing a method of attaching a magnetic sensor to a casing in the magnetic sensor device according to the embodiment of the present invention. [Figure 11] FIG. 2A is an external view showing a state in which a board-side connector in a magnetic sensor device according to an embodiment of the present invention is viewed from above, and FIG. 2B is an external view showing a state in which the board-side connector is viewed from below. [Figure 12] FIG. 1A is a cross-sectional view showing a state in which the sensor-side connector and the board-side connector are separated, and FIG. 1B is a cross-sectional view showing a state in which the sensor-side connector and the board-side connector are connected. [Figure 13] 1 is an explanatory diagram showing a state in which a board-side connector in a magnetic sensor device according to an embodiment of the present invention is provided on a board of a rotation detection device; [Figure 14] 1 is an explanatory diagram showing a magnetic sensor device according to an embodiment of the present invention provided on a substrate as viewed from the front; [Figure 15] 5A to 5C are explanatory diagrams illustrating a magnetic field detection operation of the magnetic sensor device according to the embodiment of the present invention. [Figure 16] FIG. 4 is an explanatory diagram showing a first modified example of the magnetic sensor device according to the embodiment of the present invention. [Figure 17] FIG. 11 is an explanatory diagram showing a second modified example of the magnetic sensor device according to the embodiment of the present invention. [Figure 18] FIG. 11 is an explanatory diagram showing a third modified example of the magnetic sensor device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] (Rotation detection device) Fig. 1 shows a rotation detection device 1 including a magnetic sensor device 3 according to an embodiment of the present invention. Fig. 2 shows a cross section of the rotation detection device 1 taken along line AA in Fig. 1 as viewed from the lower right in Fig. 1.

[0018] 1, the rotation detection device 1 is a device that detects the rotation of a rotating shaft 40 as a rotating body. The rotation detection device 1 includes a magnetic field forming member 2 that forms a rotating magnetic field, a plurality of magnetic sensor devices 3 that detect the rotating magnetic field, and a substrate 35.

[0019] The magnetic field forming member 2 is formed in a ring shape from a magnetic material such as ferrite. The magnetic field forming member 2 is disposed coaxially with the rotating shaft 40 on the outer periphery of the rotating shaft 40 and is fixed to the rotating shaft 40. The magnetic field forming member 2 is a magnetized with multiple poles, and on the outer periphery of the magnetic field forming member 2, four magnetic poles, N pole, S pole, N pole, S pole, are formed in that order at intervals of 90 degrees, for example, in the circumferential direction of the magnetic field forming member 2. The magnetic field forming member 2 can also be formed from four magnets that are not magnetized with multiple poles.

[0020] The substrate 35 is provided on the outer periphery of the rotating shaft 40. As shown in FIG. 2, the substrate 35 is disposed so that a plane including its mounting surface 35A is perpendicular to the axis X of the rotating shaft 40. A through hole 35B is formed in the center of the substrate 35, and the rotating shaft 40 is inserted into the through hole 35B. The diameter of the through hole 35B is larger than the outer diameter of the rotating shaft 40, and the rotating shaft 40 is not in contact with the substrate 35. The substrate 35 is fixed via a bracket or the like to a housing of a device (e.g., a motor) in which the rotating shaft 40 is rotatably supported.

[0021] A plurality of magnetic sensor devices 3 are provided on a mounting surface 35A of a substrate 35. As shown in FIG. 1, in this embodiment, three magnetic sensor devices 3 are provided on the substrate 35. The three magnetic sensor devices 3 are arranged at a predetermined interval (e.g., 120 degree intervals) on the outer periphery side of the magnetic field forming member 2. The three magnetic sensor devices 3 are arranged so that the distances from the axis X of the rotating shaft 40 are equal to each other. Each magnetic sensor device 3 is spaced apart from the magnetic field forming member 2. As shown in FIG. 2, the position of each magnetic sensor device 3 approximately coincides with the position of the magnetic field forming member 2 in the axial direction of the rotating shaft 40.

[0022] While the magnetic field forming member 2 rotates together with the rotating shaft 40, each magnetic sensor device 3 is stationary. When the magnetic field forming member 2 rotates together with the rotating shaft 40, the magnetic field formed by the magnetic field forming member 2 rotates. This creates a rotating magnetic field that rotates around the axis X of the rotating shaft 40 as the axis of rotation. Each magnetic sensor device 3 detects this rotating magnetic field. Specifically, as the magnetic field formed by the magnetic field forming member 2 rotates, the direction of the magnetic field acting on each magnetic sensor device 3 changes. Each magnetic sensor device 3 outputs a pulse signal corresponding to this change in the direction of the magnetic field. The amount and direction of rotation of the rotating shaft 40 can be detected based on the pulse signal output from each magnetic sensor device 3.

[0023] In addition, although not shown in the figure, in addition to the magnetic sensor device 3, a number of small surface-mounted electric and electronic components (hereinafter referred to as "other electric and electronic components") such as resistors, capacitors, diodes, transistors or integrated circuits are mounted on the mounting surface 35A of the substrate 35.

[0024] (Magnetic sensor device) In Fig. 1, three identical magnetic sensor devices 3 are provided on the substrate 35. Fig. 3 shows one of these three magnetic sensor devices 3. Below, this one magnetic sensor device 3 will be explained, and in this explanation, when describing the directions of front (Fd), back (Bd), up (Ud), down (Dd), left (Ld), and right (Rd), please follow the arrows drawn in the lower right corner in Figs. 3 to 12, 14, and 15.

[0025] 3, the magnetic sensor device 3 includes a sensor unit 4 and two board-side connectors 24, 25. The board-side connectors 24, 25 are mounted on a mounting surface 35A of a board 35. The sensor unit 4 is provided on the board 35 by being connected to the board-side connectors 24, 25.

[0026] (sensor unit) Fig. 4(A) shows the sensor unit 4 as viewed from the upper right rear. Fig. 4(B) shows the sensor unit 4 as viewed from the lower right front. Fig. 5 shows the magnetic sensor 5, yoke 18, and casing 19 of the sensor unit 4. Note that in Fig. 5, only the outer shape of the casing 19 is shown by a two-dot chain line.

[0027] As shown in FIGS. 4(A), 4(B) and 5, the sensor unit 4 includes a magnetic sensor 5, a yoke 18, and a casing 19, and the magnetic sensor 5 and the yoke 18 are provided inside the casing 19.

[0028] Fig. 6 shows the magnetic sensor 5. Fig. 7(A) shows the bobbin 7 of the magnetic sensor 5 as viewed from the front upper right. Fig. 7(B) shows the bobbin 7 as viewed from the rear lower right. Fig. 8(A) shows the left end of the magnetic sensor 5 as viewed from below. Fig. 8(B) shows the cross section of the left end of the magnetic sensor 5 cut along cutting line BB in Fig. 8(A) as viewed from the left.

[0029] The magnetic sensor 5 is a part that detects the rotating magnetic field in the magnetic sensor device 3. The magnetic sensor 5 includes a magnetic wire 6, a bobbin 7, a coil 12, and two sensor-side connectors 14 and 15, as shown in FIG.

[0030] The magnetic wire 6 is a magnetic wire that exhibits the large Barkhausen effect, and is called a composite magnetic wire. The magnetic wire 6 is formed, for example, from a semi-hard magnetic material containing iron and cobalt, and is a wire having a diameter of, for example, about 0.1 mm to 1 mm and a length of, for example, about 10 mm to 30 mm. The magnetic wire 6 is formed, for example, by drawing the semi-hard magnetic material and twisting it several times while changing the direction. The magnetic wire 6 has uniaxial anisotropy in which the direction in which magnetization is easily performed is the direction of the central axis of the magnetic wire 6. In addition, the magnetic wire 6 has a larger coercive force in the central part than in the outer peripheral part. The magnetic wire 6 has a property that the magnetization direction of the magnetic wire 6 (its outer peripheral part) suddenly reverses in response to a change in the direction of the external magnetic field.

[0031] The bobbin 7 is formed of a non-magnetic material such as resin. As shown in FIG. 7(A), the bobbin 7 has an electric wire winding section 8, two wire support sections 9, two flange sections 10, and a wire accommodating groove 11. The electric wire winding section 8 is provided in the left-right middle section of the bobbin 7 and is formed in a cylindrical shape extending in the left-right direction. The wire support sections 9 are provided at the left and right ends of the bobbin 7. The flange sections 10 are provided between the electric wire winding section 8 and the left wire support section 9, and between the electric wire winding section 8 and the right wire support section 9. Each flange section 10 has a larger diameter than the electric wire winding section 8. The wire accommodating groove 11 is a groove extending from the left end to the right end of the bobbin 7.

[0032] The magnetic wire 6 is arranged inside the bobbin 7 so as to extend linearly in the left-right direction. Specifically, the magnetic wire 6 is arranged in a wire accommodating groove 11. The left end of the magnetic wire 6 is supported (fixed) to the left end of the wire accommodating groove 11 formed in the left wire support part 9 by a means such as adhesion using an adhesive. Similarly, the right end of the magnetic wire 6 is supported (fixed) to the right end of the wire accommodating groove 11 formed in the right wire support part 9. Note that instead of the wire accommodating groove 11, a wire accommodating hole that is a hole extending from the left end to the right end of the bobbin 7 may be provided, and the magnetic wire 6 may be arranged in the wire accommodating hole.

[0033] The coil 12 is provided on the outer periphery of the magnetic wire 6 arranged in the wire accommodating groove 11. Specifically, the coil 12 is formed by winding an insulated electric wire 13, such as an enameled wire, around the electric wire winding portion 8, as shown in FIG.

[0034] As shown in Fig. 7(B), the sensor side connectors 14, 15 are provided at the left and right ends of the bobbin 7, respectively. Specifically, the sensor side connector 14 is integrally formed at the lower part of the left wire support part 9 in the bobbin 7. The sensor side connector 15 is integrally formed at the lower part of the right wire support part 9 in the bobbin 7. In addition, the sensor side connector 14 protrudes downward from the left wire support part 9, and the sensor side connector 15 protrudes downward from the right wire support part 9. The sensor side connector 14 is detachably connected to the board side connector 24, and the sensor side connector 15 is detachably connected to the board side connector 25.

[0035] As shown in Figs. 8(A) and 8(B), the sensor-side connector 14 includes a fitting portion 16 and a terminal 17. The fitting portion 16 is fitted to a fitting portion 27 of the board-side connector 24. The fitting portion 16 is formed in a cylindrical shape (e.g., a rectangular cylindrical shape) protruding downward from the left wire support portion 9. The terminal 17 is formed in an L-shaped bent rod shape from a conductive material, for example, a metal material such as a copper alloy. The terminal 17 is disposed in the left-right center of the rear of the fitting portion 16. One end of the terminal 17 is a wire connection portion 17A, and the other end of the terminal 17 is a contact portion 17B, with the wire connection portion 17A extending in the front-rear direction and the contact portion 17B extending in the up-down direction. The wire connection portion 17A extends rearward from the upper portion of the rear of the fitting portion 16, and its tip portion protrudes outside the bobbin 7. One end of the insulated wire 13 is fixed to and electrically connected to the wire connection portion 17A. The contact portion 17B is located at the rear inside the fitting portion 16 and extends from the upper end to the lower end of the fitting portion 16. The sensor-side connector 14 is a specific example of a "first connector", the fitting portion 16 of the sensor-side connector 14 is a specific example of a "first fitting portion", and the terminal 17 of the sensor-side connector 14 is a specific example of a "first terminal".

[0036] Sensor-side connector 15 is formed symmetrically with sensor-side connector 14, and, like sensor-side connector 14, has a fitting portion 16 and a terminal 17. The other end of insulated wire 13 is fixed to and electrically connected to wire connection portion 17A of terminal 17 of sensor-side connector 15. Sensor-side connector 15 is a specific example of a "second connector," fitting portion 16 of sensor-side connector 15 is a specific example of a "second fitting portion," and terminal 17 of sensor-side connector 15 is a specific example of a "second terminal."

[0037] The yoke 18 has a function of controlling the direction of the magnetic flux of the external magnetic field. In this embodiment, the yoke 18 controls the direction of the magnetic flux of the magnetic field formed by the magnetic field forming member 2. As shown in FIG. 5, the yoke 18 has two yoke pieces 18A. Each yoke piece 18A is formed of a soft magnetic material such as iron. A part of one yoke piece 18A is disposed in front of the left part of the magnetic sensor 5, and another part of the one yoke piece 18A is disposed above the left end part of the magnetic sensor 5. In addition, a part of the other yoke piece 18A is disposed in front of the right part of the magnetic sensor 5, and another part of the other yoke piece 18A is disposed above the right end part of the magnetic sensor 5.

[0038] The casing 19 has a function of integrating the magnetic sensor 5 and the yoke 18. The casing 19 is formed of a non-magnetic material such as resin. As shown in FIG. 9, the yoke 18 is embedded in the casing 19 and integrated with the casing 19. Specifically, the yoke 18 is integrated with the casing 19 by insert molding. Also, as shown in FIG. 10, the casing 19 is provided with a sensor accommodating section 20. The sensor accommodating section 20 is a hole formed in the lower surface of the casing 19, and is open downward with its upper portion closed. The magnetic sensor 5 is accommodated in the sensor accommodating section 20 as shown in FIG. 4(B).

[0039] In order to fit the magnetic sensor 5 into the sensor housing 20, the opening shape of the sensor housing 20 is a rectangle according to the outer shape and size of the magnetic sensor 5, the left-right dimension of the sensor housing 20 is approximately equal to the left-right dimension of the magnetic sensor 5, and the front-rear dimension of the sensor housing 20 is approximately equal to the front-rear dimensions of the left and right ends of the bobbin 7 of the magnetic sensor 5. As shown in FIG. 10, notches 21 are formed in the left and right rear parts of the casing 19. When the magnetic sensor 5 is inserted into the sensor housing 20, as shown in FIG. 4(A), the tip of the terminal 17 protruding rearward from the left end of the bobbin 7 of the magnetic sensor 5 is disposed inside the notch 21 in the left rear part of the casing 19, and the tip of the terminal 17 protruding rearward from the right end of the bobbin 7 of the magnetic sensor 5 is disposed inside the notch 21 in the right rear part of the casing 19. 10, a plurality of protrusions 22 protruding forward are formed on the rear surface of the sensor accommodating portion 20. When the magnetic sensor 5 is inserted into the sensor accommodating portion 20, each of the protrusions 22 hits the bobbin 7 hard. This fixes the magnetic sensor 5 in the sensor accommodating portion 20. When attaching the magnetic sensor 5 to the casing 19, the worker presses the magnetic sensor 5 into the sensor accommodating portion 20.

[0040] 4(B), when the magnetic sensor 5 is mounted in the sensor accommodating portion 20, the magnetic sensor 5 is disposed in the sensor accommodating portion 20 except for the sensor-side connectors 14, 15, but the sensor-side connectors 14, 15 protrude from the sensor accommodating portion 20. In other words, the sensor-side connectors 14, 15 protrude downward from the casing 19.

[0041] (Board side connector) Fig. 11(A) shows the board-side connector 24 as viewed from above. Fig. 11(B) shows the board-side connector 24 as viewed from below. Fig. 12(A) shows the state in which the sensor-side connector 14 of the magnetic sensor 5 and the board-side connector 24 are separated. Fig. 12(B) shows the state in which the sensor-side connector 14 and the board-side connector 24 are connected. Note that in Figs. 12(A) and 12(B), the magnetic sensor 5 is a cross section of the left end portion of the magnetic sensor 5 cut along the cutting line BB in Fig. 8(A) as viewed from the left, and the board-side connector 24 is a cross section of the board-side connector 24 cut along the cutting line CC in Fig. 11(A) as viewed from the left.

[0042] The sensor-side connector 14 of the magnetic sensor 5 is connected to the board-side connector 24. As shown in Fig. 11(A), the board-side connector 24 includes a housing 26 having a mating portion 27, and two terminals 33. Note that the board-side connector 24 is a specific example of a "third connector", the "mating portion 27" of the board-side connector 24 is a specific example of a "third mating portion", and the "terminal 33" of the board-side connector 24 is a specific example of a "third terminal".

[0043] The housing 26 is made of a non-magnetic material such as resin. As shown in Fig. 3, the housing 26 is formed in a columnar shape (e.g., a rectangular columnar shape) having an axis extending in the vertical direction. The board-side connector 24 of this embodiment is low-profile, and its vertical dimension is smaller than any of its horizontal and front-rear dimensions.

[0044] The fitting portion 27 is provided on the upper part of the housing 26. Specifically, as shown in Figs. 11(A) and 12(A), the fitting portion 27 includes a bottomed hole 28 formed on the upper surface of the housing 26 and a protrusion 29 protruding upward from the center of the bottom surface of the hole 28. The fitting portion 16 of the sensor side connector 14 is inserted into the space between the inner peripheral surface of the hole 28 and the outer peripheral surface of the protrusion 29. The opening shape of the hole 28 and the shape of the protrusion 29 correspond to the shape of the fitting portion 16 of the sensor side connector 14. For example, the opening shape of the hole 28 and the shape of the protrusion 29 when the board side connector 24 is viewed from above are each rectangular.

[0045] 11(B), terminal arrangement grooves 30 extending in the front-rear direction are formed in the front and rear parts of the bottom surface of housing 26 at the center in the left-right direction. As shown in FIG. 11(A), displacement allowance grooves 31 extending in the up-down direction are formed in protruding portion 29 of fitting portion 27 at the center in the left-right direction in the front and rear parts. Furthermore, terminal fixing holes 32 extending in the up-down direction are formed in housing 26 at the center in the left-right direction in the front and rear parts.

[0046] The two terminals 33 are disposed at the front and rear of the central portion of the housing 26 in the left-right direction. As shown in FIG. 12(A), each terminal 33 is formed in an L-shaped bent rod shape from a conductive material, for example, a metal material such as a copper alloy. One end of each terminal 33 is a board connection portion 33A, and the other end of the terminal 17 is a contact portion 33B, with the board connection portion 33A extending in the front-rear direction and the contact portion 33B extending in the up-down direction. Each terminal 33 is provided with a fixing portion 33C for fixing the terminal 33 to the housing 26, and the fixing portion 33C protrudes upward from the board connection portion 33A.

[0047] In the rear terminal 33, the board connection portion 33A is disposed in the terminal arrangement groove 30 formed in the rear part of the lower surface of the housing 26. The board connection portion 33A extends along the lower surface of the housing 26, and its tip portion protrudes rearward from the terminal arrangement groove 30 and protrudes to the outside of the housing 26. The contact portion 33B is disposed in a position close to the rear surface of the protrusion 29, and extends along the rear surface of the protrusion 29 from the terminal arrangement groove 30 to the upper surface of the housing 26. The contact portion 33B is located behind the displacement allowance groove 31 (in this embodiment, a part of the contact portion 33B is inserted in the displacement allowance groove 31). The fixed portion 33C is inserted into the terminal fixing hole 32 formed in the rear part of the housing 26. A locking piece is formed on the fixed portion 33C, and the fixed portion 33C is fixed in the terminal fixing hole 32 by the locking piece being hooked on the inner peripheral surface of the terminal fixing hole 32. As a result, the rear terminal 33 is fixed to the housing 26.

[0048] The front terminals 33 are arranged symmetrically with the rear terminals 33. That is, in the front terminals 33, the board connection portion 33A is arranged in the terminal arrangement groove 30 formed in the front part of the lower surface of the housing 26, and the tip portion thereof protrudes forward from the terminal arrangement groove 30. The contact portion 33B is arranged in a position close to the front surface of the protrusion 29, and is located in front of the displacement allowance groove 31. The fixing portion 33C is fixed in the terminal fixing hole 32 formed in the front part of the housing 26, whereby the front terminals 33 are fixed to the housing 26.

[0049] 3, the magnetic sensor device 3 has two board-side connectors 24, 25, but the board-side connector 25 is identical to the board-side connector 24. Note that the board-side connector 25 is a specific example of a "fourth connector," the "fitting portion 27" of the board-side connector 25 is a specific example of a "fourth fitting portion," and the "terminal 33" of the board-side connector 25 is a specific example of a "fourth terminal."

[0050] As shown in FIG. 12B, the fitting portion 16 of the sensor-side connector 14 provided at the left end of the bobbin 7 of the magnetic sensor 5 enters into the fitting portion 27 of the board-side connector 24, so that the two are fitted together. The fitting portion 16 and the fitting portion 27 are fitted together, so that the sensor-side connector 14 is fixed to the board-side connector 24. Note that a locking mechanism or a locking mechanism may be provided for the fitting portion 16 and the fitting portion 27 in order to more firmly fix the sensor-side connector 14 to the board-side connector 24. In addition, when the fitting portion 16 is fitted into the fitting portion 27, the contact portion 17B of the terminal 17 of the sensor-side connector 14 comes into contact with the contact portion 33B of the terminal 33 of the board-side connector 24 and presses the contact portion 33B. The contact portion 33B is elastically deformed and displaced forward, and enters the displacement allowance groove 31. As a result, the contact portion 17B and the contact portion 33B come into strong contact with each other, and the two are electrically connected. Similarly, the fitting portion 16 of the sensor side connector 15 provided at the right end of the bobbin 7 of the magnetic sensor 5 enters into the fitting portion 27 of the board side connector 25, so that the two are fitted together and fixed. At this time, the contact portion 17B of the terminal 17 of the sensor side connector 15 comes into strong contact with the contact portion 33B of the terminal 33 of the board side connector 25, and the two are electrically connected. The fitting between the fitting portion 16 and the fitting portion 27 can be released by, for example, pulling the sensor unit 4 relative to the board 35.

[0051] Furthermore, since both board side connectors 24, 25 have a front-to-back symmetrical structure, when mounting board side connectors 24, 25 on board 35, even if the front-to-back orientation of board side connector 24 is reversed, there is no problem with the connection between sensor side connector 14 and board side connector 24, and even if the front-to-back orientation of board side connector 25 is reversed, there is no problem with the connection between sensor side connector 15 and board side connector 25.

[0052] (Installation of magnetic sensor device on substrate) As shown in FIG. 1, when three magnetic sensor devices 3 are provided on a substrate 35 to form a rotation detection device 1, the three magnetic sensor devices 3 are arranged at intervals of 120 degrees on the outer periphery of the magnetic field forming member 2, and are arranged so that the distances between the three magnetic sensor devices 3 and the axis X of the rotating shaft 40 are equal to each other, and the front of each magnetic sensor device 3 faces toward the axis X of the rotating shaft 40.

[0053] The three magnetic sensor devices 3 are provided on the substrate 35 in the following manner.

[0054] First, the board-side connectors 24, 25 of the three magnetic sensor devices 3 are surface-mounted on the mounting surface 35A of the substrate 35 as shown in FIG. 13. When the board-side connectors 24, 25 are surface-mounted on the mounting surface 35A of the substrate 35, the positions of the board-side connectors 24, 25 on the mounting surface 35A of the substrate 35 are determined so that they correspond to the positions of the sensor-side connectors 14, 15 of the three magnetic sensor devices 3 arranged as shown in FIG. 1. Next, the lower surfaces of the housings 26 of the board-side connectors 24, 25 are placed on the mounting surface 35A of the substrate 35. By placing the lower surface of the housing 26 of the board-side connector 24 on the mounting surface 35A of the substrate 35, the board-side connector 24 is provided on the mounting surface 35A of the substrate 35 so that the fitting portion 16 of the sensor-side connector 14 can be fitted to the fitting portion 27 of the board-side connector 24 from above. In addition, by placing the lower surface of the housing 26 of the board-side connector 25 on the mounting surface 35A of the board 35, the board-side connector 25 is provided on the mounting surface 35A of the board 35 so that the fitting portion 16 of the sensor-side connector 15 can be fitted to the fitting portion 27 of the board-side connector 25 from above. Next, the board connection portion 33A of each terminal 33 of the board-side connectors 24, 25 is soldered to the conductive portion provided on the mounting surface 35A of the board 35 by a reflow soldering method. By soldering the board connection portion 33A of each terminal 33 of the board-side connectors 24, 25 to the conductive portion on the mounting surface 35A, the terminals 33 of the board-side connectors 24, 25 are electrically connected to the conductive portion of the board 35, and the board-side connectors 24, 25 are fixed to the board 35.

[0055] Next, the sensor units 4 of the three magnetic sensor devices 3 are connected to the board-side connectors 24, 25, respectively. Specifically, in each magnetic sensor device 3, the fitting portions 16 of the sensor-side connectors 14, 15 of the magnetic sensor 5 fixed to the casing 19 are fitted from above into the fitting portions 27 of the board-side connectors 24, 25, respectively. As a result, the terminals 17 of the sensor-side connectors 14, 15 are electrically connected to the terminals 33 of the board-side connectors 24, 25, respectively. In addition, the sensor unit 4 is fixed to the board 35.

[0056] FIG. 14 shows a state in which one magnetic sensor device 3 provided on a substrate 35 is seen from the front. In FIG. 14, the magnetic sensor 5 is indicated by a broken line, but the yoke 18 is omitted. When the magnetic sensor device 3 is provided on the substrate 35, as shown in FIG. 14, the substrate side connectors 24 and 25 of the magnetic sensor device 3 are arranged on the mounting surface 35A of the substrate 35 in a state separated from each other. In addition, the housings 26 of the substrate side connectors 24 and 25 protrude upward from the mounting surface 35A of the substrate 35. In addition, the extension direction of the magnetic wire 6 and the bobbin 7 of the magnetic sensor 5 is parallel to the mounting surface 35A of the substrate 35. In addition, the sensor unit 4 is arranged so as to bridge between the substrate side connector 24 and the substrate side connector 25 that are separated from each other, and as a result, a space S in which other electric and electronic components can be mounted is formed between the lower surface of the center part of the sensor unit 4 in the left-right direction (below the outer peripheral surface of the coil 12 of the magnetic sensor 5) and the mounting surface 35A of the substrate 35.

[0057] (Magnetic field detection operation of the magnetic sensor device) 15(A) shows the positional relationship between the magnetic sensors 5 and yokes 18 in three magnetic sensor devices 3 provided on a substrate 35, and the magnetic field forming members 2. Hereinafter, the magnetic field detection operation of the magnetic sensor device 3 will be described, focusing on one of the three magnetic sensor devices 3 in FIG. 15(A) that is disposed on the upper side.

[0058] In FIG. 15(A), the S pole of the magnetic field forming member 2 approaches the left front of one of the upper magnetic sensor devices 3, and the N pole of the magnetic field forming member 2 approaches the right front of the magnetic sensor device 3. When the rotating shaft 40 rotates 90 degrees clockwise from this state, as shown in FIG. 15(B), the N pole of the magnetic field forming member 2 approaches the left front of the magnetic sensor device 3, and the S pole of the magnetic field forming member 2 approaches the right front of the magnetic sensor device 3. At this time, the direction of the magnetic field acting on the magnetic wire 6 of the magnetic sensor device 3 becomes rightward. As a result, the magnetization direction of the magnetic wire 6, which was leftward until just before, is suddenly reversed to the right. As a result, as shown in FIG. 15(D), for example, a positive current pulse P1 is generated in the coil 12.

[0059] After that, when the rotating shaft 40 rotates further clockwise by 90 degrees, the S pole of the magnetic field generating member 2 approaches the left front side of the magnetic sensor device 3, and the N pole of the magnetic field generating member 2 approaches the right front side of the magnetic sensor device 3, as shown in FIG. 15(C). At this time, the direction of the magnetic field acting on the magnetic wire 6 of the magnetic sensor device 3 becomes leftward. As a result, the magnetization direction of the magnetic wire 6, which was rightward until just before, is suddenly reversed to leftward. As a result, a current pulse P2, for example, in the negative direction, is generated in the coil 12, as shown in FIG. 15(D).

[0060] One end of the insulated wire 13 forming the coil 12 is connected to a detection circuit provided on the substrate 35, for example, via a terminal 17 of the sensor-side connector 14, a terminal 33 of the substrate-side connector 24, and one conductive part provided on the mounting surface 35A of the substrate 35. The other end of the insulated wire 13 forming the coil 12 is connected to the detection circuit via a terminal 17 of the sensor-side connector 15, a terminal 33 of the substrate-side connector 25, and another conductive part provided on the mounting surface 35A of the substrate 35. With this configuration, the current pulses P1 and P2 generated in the coil 12 are output to the detection circuit as pulse signals.

[0061] The detection circuit detects the amount and direction of rotation of the rotating shaft 40 based on pulse signals output from the coils 12 of the magnetic sensors 5 of the three magnetic sensor devices 3 provided on the substrate 35. Note that the method of detecting the amount and direction of rotation of the rotating shaft 40 in the rotation detection device 1 may be, for example, the method described in International Publication No. WO 2016 / 002437.

[0062] In order to increase the level of the current pulse generated in the coil 12 or to sharpen the waveform of the current pulse, it is preferable to concentrate the magnetic flux of the magnetic field formed by the two magnetic poles of the magnetic field forming member 2 close to the left front and right front of the magnetic sensor device 3 on the magnetic wire 6. As shown in FIG. 15(B) or 15(C), a yoke 18 is disposed between the magnetic sensor 5 and the magnetic field forming member 2. The yoke 18 controls the direction of the magnetic flux so that the magnetic flux of the magnetic field formed by the two magnetic poles of the magnetic field forming member 2 close to the left front and right front of the magnetic sensor device 3 is concentrated on the magnetic wire 6. The arrows F in FIG. 15(B) and 15(C) indicate the flow of the magnetic flux whose direction is controlled by the yoke 18. By concentrating the magnetic flux on the magnetic wire 6 by the yoke 18, the magnetic flux flows along the extension direction of the magnetic wire 6, and the magnetic flux is surely passed through the magnetic wire 6.

[0063] As described above, the magnetic sensor device 3 according to the embodiment of the present invention includes the sensor unit 4 including the magnetic sensor 5, and the board-side connectors 24 and 25, and the magnetic sensor 5 includes the sensor-side connectors 14 and 15. The board-side connectors 24 and 25 are surface-mounted on the mounting surface 35A of the board 35 by reflow soldering, and then the sensor-side connectors 14 and 15 are connected to the board-side connectors 24 and 25, so that the magnetic sensor device 3 can be provided on the board 35. The volume of the board-side connectors 24 and 25 is small compared to the overall volume of the magnetic sensor device 3, and therefore the heat capacity of the board-side connectors 24 and 25 is small compared to the overall heat capacity of the magnetic sensor device 3. Therefore, the difference in heat capacity between the board-side connectors 24 and 25 and other electric / electronic components surface-mounted on the mounting surface 35A of the board 35 is smaller than the difference in heat capacity between the entire magnetic sensor device 3 and other electric / electronic components surface-mounted on the mounting surface 35A of the board 35. Therefore, by using the reflow soldering method, the board-side connectors 24, 25 and other electric and electronic components can be easily surface-mounted at once on the mounting surface 35A of the board 35. Therefore, when the magnetic sensor device 3 and other electric and electronic components are provided on the board 35, the number of soldering steps can be reduced.

[0064] 14, when the magnetic sensor device 3 is provided on the mounting surface 35A of the substrate 35, a space S in which other electric / electronic components can be mounted is formed between the lower surface of the left-right center of the sensor unit 4 (the lower part of the outer circumferential surface of the coil 12 of the magnetic sensor 5) and the mounting surface 35A of the substrate 35. Therefore, by utilizing this space S, the space for mounting other electric / electronic components on the mounting surface 35A of the substrate 35 can be expanded, and the number of other electric / electronic components to be mounted on the mounting surface 35A of the substrate 35 can be increased.

[0065] Moreover, the magnetic sensor device 3 can be easily attached to and detached from the board 35 by inserting and removing the sensor-side connectors 14, 15 into and from the board-side connectors 24, 25. Therefore, the magnetic sensor device 3 can be easily replaced.

[0066] Furthermore, the sensor unit 4 of the magnetic sensor device 3 has a structure in which the magnetic sensor 5 and the yoke 18 are integrated via the casing 19. This makes it easier to attach the magnetic sensor 5 and the yoke 18 to the substrate 35, and also improves the accuracy of the arrangement of the magnetic sensor 5 and the yoke 18, compared to a case in which the magnetic sensor 5 and the yoke 18 are separate and distinct from each other.

[0067] Furthermore, by integrating the yoke 18 with the casing 19 by insert molding, the sensor unit 4 can be easily assembled, and the accuracy of the arrangement of the magnetic sensor 5 and the yoke 18 can be further improved.

[0068] Furthermore, magnetic field detection by the magnetic sensor device uses the large Barkhausen effect of a magnetic wire, and therefore can be performed without a power source.

[0069] As shown in FIG. 16, the casings 19 of the sensor units 4 of the three magnetic sensor devices may be connected via a connecting portion 45.

[0070] In the above embodiment, the magnetic sensor 5 and the yoke 18 are integrated via the casing 19, but the present invention is not limited to this. For example, as shown in Fig. 17, the magnetic sensor 5 and the yoke 18 may be integrated using a means such as screws or adhesive, without using a casing.

[0071] Further, although the board-side connector 24 in the above embodiment is provided with two terminals 33, the board-side connector 24 may be provided with only one terminal 33. The same applies to the board-side connector 25.

[0072] In the above embodiment, the sensor-side connector 14 having the fitting portion 16 and the terminal 17 is provided at one end of the bobbin 7 of the magnetic sensor 5, and the board-side connector 24 having the housing 26 having the fitting portion 27 and the terminal 33 is provided at the board 35 as a connector to which the sensor-side connector 14 is connected. However, for example, the sensor-side connector 51 shown in FIG. 18 may be provided at one end of the bobbin 7 of the magnetic sensor 5, and the board-side connector 61 shown in FIG. 18 may be provided at the board 35 as a connector to which the sensor-side connector 51 is connected. In FIG. 18, the sensor-side connector 51 is composed only of a terminal 52 having an electric wire connection portion 52A and a contact portion 52B. The contact portion 52B is disposed in a recess 53 provided on the lower surface of the wire support portion 9 of the bobbin 7. On the other hand, the board-side connector 61 is formed only of a sleeve-shaped terminal 62. The terminal 62 is surface-mounted on the mounting surface 35A of the board 35 and opens upward. The contact portion 52B of the terminal 52 is fitted (inserted) into the sleeve-shaped terminal 62 from above. This connects the sensor side connector 51 to the board side connector 61. With this structure, the contact portion 52B of the terminal 52 of the sensor side connector 51 and the sleeve-shaped terminal 62 of the board side connector 61 each function as a fitting portion. Therefore, the terminal 52 of the sensor side connector 51 is both a terminal and a fitting portion, and the terminal 62 of the board side connector 61 is both a terminal and a fitting portion. Similarly, the sensor side connector 51 shown in FIG. 18 may be provided at the other end of the bobbin 7 of the magnetic sensor 5, and the board side connector 61 shown in FIG. 18 may be provided on the board 35 as a connector to which the sensor side connector 51 provided at the other end of the bobbin 7 of the magnetic sensor 5 is connected.

[0073] The magnetic sensor device of the present invention may be embodied without using a yoke.The magnetic sensor device of the present invention may be applied to devices other than a rotation detection device.

[0074] Furthermore, the present invention can be modified as appropriate within the scope that does not contradict the gist or concept of the invention that can be read from the claims and the entire specification, and magnetic sensor devices involving such modifications are also included in the technical concept of the present invention. [Explanation of symbols]

[0075] 3. Magnetic sensor device 5. Magnetic Sensor 6 Magnetic wire 7 Bobbin 12 Coils 13 Insulated wire (wire) 14, 15, 51 Sensor side connector (first connector, second connector) 16 Fitting portion (first fitting portion, second fitting portion) 17, 52 Terminal (1st terminal, 2nd terminal) 18 York 19 Casing 24, 25, 61 Board side connector (3rd connector, 4th connector) 27 Fitting portion (third fitting portion, fourth fitting portion) 33, 62 terminals (third terminal, fourth terminal) 35 Substrate

Claims

1. a magnetic sensor including a magnetic wire that exhibits a large Barkhausen effect, a bobbin in which the magnetic wire is disposed, a coil formed by winding an electric wire around the bobbin, a first connector provided at one end of the bobbin, and a second connector provided at the other end of the bobbin; a third connector detachably connected to the first connector; a fourth connector detachably connected to the second connector, the first connector includes a first fitting portion and a first terminal to which one end of the electric wire is connected; the second connector includes a second fitting portion and a second terminal to which the other end of the electric wire is connected, the third connector includes a third fitting portion that is fitted with the first fitting portion, and a third terminal that contacts the first terminal when the first fitting portion is fitted with the third fitting portion; A magnetic sensor device characterized in that the fourth connector has a fourth mating portion that mates with the second mating portion, and a fourth terminal that contacts the second terminal when the second mating portion is mated with the fourth mating portion.

2. 2. The magnetic sensor device of claim 1, wherein the coil is provided between one end and the other end of the bobbin, the first connector is provided under one end of the bobbin, the second connector is provided under the other end of the bobbin, the third connector is provided on the upper surface of the substrate so that the first fitting portion can be fitted into the third fitting portion from above the third fitting portion, and the fourth connector is provided on the upper surface of the substrate so that the second fitting portion can be fitted into the fourth fitting portion from above the fourth fitting portion, the third connector and the fourth connector are arranged apart from each other on the upper surface of the substrate, and when the first fitting portion is fitted into the third fitting portion from above the third fitting portion and the second fitting portion is fitted into the fourth fitting portion from above the fourth fitting portion, the magnetic wire and the bobbin extend parallel to the upper surface of the substrate, and a space is formed between the lower part of the outer circumferential surface of the coil and the upper surface of the substrate.

3. The magnetic sensor device according to claim 1 , wherein the third connector and the fourth connector are each surface-mounted on a substrate.

4. A yoke is provided for controlling the direction of the magnetic flux of an external magnetic field; 2. The magnetic sensor device according to claim 1, wherein the yoke is fixed to the magnetic sensor.

5. A yoke for controlling the direction of the magnetic flux of an external magnetic field; a casing in which the magnetic sensor is housed; 2. The magnetic sensor device according to claim 1, wherein the yoke is fixed to the casing.

6. 6. The magnetic sensor device according to claim 5, wherein the yoke is integrated with the casing by insert molding.

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