Magnetoelectric conversion device

Abstract

To provide a magnetoelectric conversion device that can convert the magnetic field generated from an object into electricity and be used for purposes such as displacement measurement or power storage.SOLUTION: A magnetoelectric conversion device (3) is a device that converts a magnetic field generated from an object into electricity, and includes magnetostrictive members (11, 12) that are deformed by the magnetic field, a piezoelectric member (13) that is fixed to the magnetostrictive members (11, 12) and bends due to the deformation of the magnetostrictive members (11, 12), and a calculation unit (80) that receives a voltage output from the piezoelectric member (13) due to the bending of the piezoelectric member (13) and calculates the position of the object on the basis of the voltage.SELECTED DRAWING: Figure 13

Description

[Technical field]

[0001] The present disclosure relates to a magnetoelectric conversion device that converts a magnetic field generated from an object into electricity for use. [Background technology]

[0002] As a magnetoelectric conversion device that converts a magnetic field generated from an object into electricity and utilizes it, a current sensor that converts a magnetic field generated from a current line into electricity and measures current has been proposed (see, for example, Patent Document 1). This current sensor includes a piezoelectric element and first and second magnetostrictive bodies laminated on the upper and lower surfaces of the piezoelectric element, and measures the current flowing through the current line based on the voltage between the electrodes of the piezoelectric element, which is deformed in response to deformation of the first and second magnetostrictive bodies by a magnetic field. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-011989 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the use of the device described in Patent Document 1 is limited to use as a current sensor, and cannot be used for purposes such as displacement measurement or power storage.

[0005] An object of the present disclosure is to provide a magnetoelectric conversion device that can convert a magnetic field generated from an object into electricity and utilize it for purposes such as displacement measurement or electricity storage. [Means for solving the problem]

[0006] The magnetoelectric conversion device disclosed herein is a device that converts a magnetic field generated from an object into electricity, and includes a magnetostrictive member that deforms due to the magnetic field, a piezoelectric member that is fixed to the magnetostrictive member and curves due to the deformation of the magnetostrictive member, a calculation unit that receives a voltage output from the piezoelectric member due to the bending of the piezoelectric member and calculates the position of the object based on the voltage, and a bias magnet that applies a bias magnetic field to the magnetostrictive member to expand or contract the magnetostrictive member, wherein the magnetostrictive member and the piezoelectric member are stacked to form a magnetoelectric conversion unit, and the magnetoelectric conversion unit is maintained in a curved or uncurved state due to the expansion or contraction of the magnetostrictive member due to the bias magnetic field.

[0007] Another magnetoelectric conversion device of the present disclosure is a device that converts a magnetic field generated from an object into electricity and utilizes it, and includes a magnetostrictive member that deforms due to the magnetic field, a piezoelectric member fixed to the magnetostrictive member and curved due to the deformation of the magnetostrictive member, a storage unit that receives a voltage output from the piezoelectric member due to the bending of the piezoelectric member and stores electric power based on the voltage in a storage battery, and a bias magnet that applies a bias magnetic field to the magnetostrictive member to expand or contract the magnetostrictive member, wherein the magnetostrictive member and the piezoelectric member are stacked to form a magnetoelectric conversion unit, and the magnetoelectric conversion unit is maintained in a curved or uncurved state due to the expansion or contraction of the magnetostrictive member due to the bias magnetic field. Effect of the Invention

[0008] According to the device of the present disclosure, a magnetic field generated from an object can be converted into electricity and used for purposes such as displacement measurement or electricity storage. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic diagram showing a configuration of a magnetoelectric conversion device (electricity storage device) according to a first embodiment. [Diagram 2] 1 is a schematic perspective view showing a configuration of a magnetoelectric converting unit of a magnetoelectric converting device according to a first embodiment. [Diagram 3]5A and 5B are schematic cross-sectional views illustrating the operation of a magnetoelectric conversion unit of the magnetoelectric conversion device according to the first embodiment. [Figure 4] 6(A) and 6(B) are schematic cross-sectional views showing another example of the operation of the magnetoelectric conversion unit of the magnetoelectric conversion device according to the first embodiment. [Diagram 5] 10 is a schematic diagram showing a configuration of a magnetoelectric conversion device (electricity storage device) according to a modified example of the first embodiment. FIG. [Figure 6] 13(A) and 13(B) are schematic cross-sectional views illustrating the operation of a magnetoelectric converting unit of a magnetoelectric converting device according to a modification of the first embodiment. [Figure 7] 11 is a schematic diagram showing a configuration of a magnetoelectric conversion device (electricity storage device) according to a second embodiment. FIG. [Figure 8] 13(A) and 13(B) are schematic cross-sectional views illustrating the operation of a magnetoelectric conversion unit of a magnetoelectric conversion device according to a second embodiment. [Figure 9] 13 is a schematic diagram showing a configuration of a magnetoelectric conversion device (electricity storage device) according to a first modification of the second embodiment. FIG. [Figure 10] 13(A) and 13(B) are schematic cross-sectional views illustrating the operation of a magnetoelectric conversion unit of a magnetoelectric conversion device according to a first modification of the second embodiment. [Figure 11] 13 is a schematic diagram showing a configuration of a magnetoelectric conversion device (electricity storage device) according to a second modification of the second embodiment. FIG. [Figure 12] 13 is a schematic diagram showing a configuration of a magnetoelectric conversion device (electricity storage device) according to a third modification of the second embodiment. FIG. [Figure 13] 11 is a schematic diagram showing a configuration of a magnetoelectric conversion device (displacement measuring device) according to a third embodiment. FIG. [Figure 14] FIG. 11 is a schematic perspective view showing the configuration of a magnetoelectric converting section of a magnetoelectric converting device according to a third embodiment. [Figure 15] 13(A) and 13(B) are schematic cross-sectional views illustrating the operation of a magnetoelectric conversion unit of a magnetoelectric conversion device according to a third embodiment. [Figure 16] 13 is a schematic diagram showing a configuration of a magnetoelectric conversion device (displacement measuring device) according to a fourth embodiment. FIG. [Figure 17] FIG. 11 is a schematic perspective view showing the configuration of a magnetoelectric converting section of a magnetoelectric converting device according to a fourth embodiment. [Figure 18] 13(A) and 13(B) are schematic cross-sectional views illustrating the operation of a magnetoelectric conversion unit of a magnetoelectric conversion device according to a fourth embodiment. [Figure 19] 13 is a schematic diagram showing a configuration of a magnetoelectric conversion device (displacement measuring device) according to a fifth embodiment. FIG. [Figure 20] 13 is a schematic perspective view showing a configuration of a magnetoelectric converting section of a magnetoelectric converting device according to a fifth embodiment. FIG. [Figure 21] 13(A) and 13(B) are schematic cross-sectional views illustrating the operation of a magnetoelectric conversion unit of a magnetoelectric conversion device according to a fifth embodiment. [Figure 22] 13 is a schematic diagram showing a configuration of a magnetoelectric conversion device (displacement measuring device) according to a sixth embodiment. FIG. [Diagram 23] 13 is a schematic perspective view showing a configuration of a magnetoelectric converting section of a magnetoelectric converting device according to a sixth embodiment. FIG. [Figure 24] 13(A) and 13(B) are schematic cross-sectional views illustrating the operation of a magnetoelectric conversion unit of a magnetoelectric conversion device according to a sixth embodiment. [Diagram 25] 13 is a schematic diagram showing a configuration of a magnetoelectric conversion device (displacement measuring device) according to a seventh embodiment. FIG. [Figure 26] 13 is a schematic diagram showing a configuration of a magnetoelectric conversion device (electricity storage device) according to an eighth embodiment. FIG. [Figure 27] 13 is a schematic diagram showing a configuration of a magnetoelectric conversion device (electricity storage device) according to a ninth embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Magnetoelectric conversion devices according to embodiments will be described below with reference to the drawings. The following embodiments are merely examples, and the embodiments can be combined as appropriate and each embodiment can be modified as appropriate. In addition, the coordinate axes of an xyz orthogonal coordinate system are shown in the drawings to facilitate understanding of the relationship between the drawings. The x-axis is a coordinate axis extending in the longitudinal direction of the magnetostrictive member and the piezoelectric member, the y-axis is a coordinate axis extending in the width direction (i.e., the short direction) of the magnetostrictive member and the piezoelectric member, and the z-axis is a coordinate axis extending in the thickness direction of the piezoelectric member. In addition, in each drawing, the same reference numerals are used for the same configuration or configurations having similar functions.

[0011] The magnetoelectric conversion device according to the embodiment is a device that converts a magnetic field generated from an object into electricity for use. An example of a magnetic field generated from an object is a magnetic field generated from a current line through which an AC current or a DC current (period of current value fluctuation) flows. Another example of a magnetic field generated from an object is a magnetic field generated from a moving (including vibrating) magnet.

[0012] An example of the magnetoelectric conversion device according to the embodiment is a displacement measuring device that measures the displacement (e.g., position or distance) of an object based on electricity (e.g., voltage) converted from a magnetic field. Another example of the magnetoelectric conversion device according to the embodiment is a power storage device that stores electricity converted from a magnetic field in a storage battery.

[0013] First Embodiment Fig. 1 is a schematic diagram showing the configuration of a magnetoelectric conversion device 1 according to embodiment 1. Fig. 2 is a schematic perspective view showing the configuration of a magnetoelectric conversion unit 10 of the magnetoelectric conversion device 1. The magnetoelectric conversion device 1 is a device that converts a magnetic field generated from a current line 100, which is an object arranged at a position facing the lower surface of the magnetoelectric conversion unit 10, into electricity and utilizes the electricity. The magnetoelectric conversion device 1 is an electricity storage device.

[0014] The magnetoelectric conversion device 1 includes magnetostrictive members 11 and 12 that are deformed by a magnetic field, a piezoelectric member (i.e., a piezoelectric element) 13 that is fixed to the magnetostrictive members 11 and 12 and curves due to the deformation of the magnetostrictive members 11 and 12, and a storage unit 60 that receives a voltage output from the piezoelectric member 13 due to the bending of the piezoelectric member 13 and stores electric power based on this voltage in a storage battery. As a piezoelectric material constituting the piezoelectric member 13, for example, lead zirconate titanate (PZT) is used. As a magnetostrictive material forming the magnetostrictive members 11 and 12, for example, an alloy called Terfenol-D, which is made of iron (Fe), dysprosium (Dy), and terbium (Tb), is used. The magnetostrictive members 11 and 12 are arranged so as to sandwich the piezoelectric member 13. The magnetostrictive members 11 and 12 are fixed to both sides of the piezoelectric member 13 by, for example, an adhesive. The magnetostrictive member 11 is also called a "first magnetostrictive member". Magnetostrictive member 12 is also referred to as a “second magnetostrictive member.” Magnetostrictive members 11 and 12 each have, for example, a thickness of 1.0 mm, a width in the y direction of 6 mm, and a length in the x direction of 12 mm, and piezoelectric member 13 has a length in the x direction of 15 mm.

[0015] The magnetostrictive members 11 and 12 are plate-shaped and long in the x direction. The magnetostrictive members 11 and 12 expand or contract in the longitudinal direction of the magnetostrictive members 11 and 12 due to a magnetic field. That is, one of the magnetostrictive members 11 and 12 expands in the longitudinal direction, and the other of the magnetostrictive members 11 and 12 contracts in the longitudinal direction. The magnetostrictive members 11 and 12 and the piezoelectric member 13 constitute a magnetoelectric conversion unit 10.

[0016] 3A and 3B are schematic cross-sectional views showing the operation of the magnetoelectric conversion unit 10 of the magnetoelectric conversion device 1 according to the first embodiment. FIG. 3A shows how the magnetostrictive member 11 expands (extends in the x direction) and the magnetostrictive member 12 contracts (shrinks in the x direction) when a magnetic field M1 in the +x direction is applied to the magnetostrictive members 11 and 12 by a current flowing through the current line 100. At this time, the piezoelectric member 13 curves in a downward convex shape (i.e., an upward concave shape). FIG. 3B shows how the magnetostrictive member 11 contracts (shrinks in the x direction) and the magnetostrictive member 12 expands (extends in the x direction) when a magnetic field M2 in the -x direction is applied to the magnetostrictive members 11 and 12 by a current flowing through the current line 100. At this time, the piezoelectric member 13 curves in an upward convex shape (i.e., a downward concave shape).

[0017] 4(A) and (B) are schematic cross-sectional views showing another example of the operation of the magnetoelectric conversion unit of the magnetoelectric conversion device 1 according to the first embodiment. FIG. 4(A) shows how the magnetostrictive member 11 expands (extends in the x direction) and the magnetostrictive member 12 contracts (shrinks in the x direction) when a magnetic field M2 in the -x direction is applied to the magnetostrictive members 11 and 12 by a current flowing through the current line 100. At this time, the piezoelectric member 13 curves in a downward convex shape (i.e., an upward concave shape). FIG. 4(B) shows how the magnetostrictive member 11 contracts (shrinks in the x direction) and the magnetostrictive member 12 expands (extends in the x direction) when a magnetic field M1 in the +x direction is applied to the magnetostrictive members 11 and 12 by a current flowing through the current line 100. At this time, the piezoelectric member 13 curves in an upward convex shape (i.e., a downward concave shape).

[0018] The power storage unit 60 includes a rectifier circuit 61 that rectifies (for example, full-wave rectification) the AC voltage generated by repeating the operations shown in Figures 3(A) and (B) or Figures 4(A) and (B), and a power storage circuit 62 that stores power based on the rectified AC voltage in a storage battery. The storage battery is provided inside or outside the power storage unit 60. The power storage unit 60 may have a processor that operates by software.

[0019] Fig. 5 is a schematic diagram showing the configuration of a magnetoelectric conversion device 1a according to a modified example of the first embodiment. Figs. 6(A) and (B) are schematic cross-sectional views showing the operation of the magnetoelectric conversion unit 14 of the magnetoelectric conversion device 1a. The magnetoelectric conversion device 1a is a device that converts a magnetic field generated from a current line 100, which is an object arranged at a position facing the lower surface of the magnetoelectric conversion unit 10a, into electricity and utilizes the electricity. The magnetoelectric conversion device 1a is an electricity storage device.

[0020] The magnetoelectric conversion device 1a shown in FIG. 5 differs from the magnetoelectric conversion device 1 shown in FIG. 1 in that the magnetoelectric conversion unit 14 is composed of a magnetostrictive member 11 and a piezoelectric member 13 fixed thereto. As shown in FIG. 5, the magnetostrictive member 11 does not necessarily have to be provided on both sides of the piezoelectric member 13. The magnetoelectric conversion unit may also be composed of the magnetostrictive member 12 shown in FIG. 1 and the piezoelectric member 13 fixed thereto. The magnetoelectric conversion unit 10a composed of one magnetostrictive member and the piezoelectric member 13 is also applicable to the embodiments 2 to 9 described below.

[0021] According to the magnetoelectric conversion devices 1 and 1a, it is possible to use the power stored in the storage battery to drive a Hall element (not shown) or a current sensor (not shown) for detecting a current flowing through the current line 100. In addition, it is possible to use the power stored in the storage battery to drive an environmental sensor (not shown) such as a temperature (humidity) sensor to monitor the environment around the current line 100, such as the temperature and humidity. In addition, it is possible to wirelessly transmit sensor information by using the power stored in the storage battery to drive a wireless communication device such as Bluetooth (registered trademark). In this case, it is possible to eliminate wiring from an external power source for the current sensor, the environmental sensor, and the wireless communication device, and also to eliminate wiring for transmitting detected data.

[0022] Second Embodiment Fig. 7 is a schematic diagram showing the configuration of a magnetoelectric conversion device 2 according to embodiment 2. Figs. 8(A) and (B) are schematic cross-sectional views showing the operation of the magnetoelectric conversion unit 10 of the magnetoelectric conversion device 2. The magnetoelectric conversion device 2 is a device that converts a magnetic field generated from a current line 100, which is an object arranged at a position facing the lower surface of the magnetoelectric conversion unit 10, into electricity and utilizes the electricity. The magnetoelectric conversion device 2 is an electricity storage device.

[0023] The magnetoelectric conversion device 2 shown in FIG. 7 differs from the magnetoelectric conversion device 1 shown in FIG. 1 in that it further includes a bias magnet 20 that applies a bias magnetic field B1 that expands the magnetostrictive member 11 and contracts the magnetostrictive member 12. As shown in FIG. 7, in the magnetoelectric conversion device 2, when no current flows through the current line 100, the magnetoelectric conversion unit 10 is curved by the bias magnetic field B1, and as shown in FIGS. 8(A) and (B), even when a current flows through the current line 100, the magnetoelectric conversion unit 10 is only curved downwardly convexly. The bias magnet 20 is, for example, an NdFeB magnet, which is a rare earth magnet. The NdFeB magnet is a magnet whose main components are neodymium (Nd), iron (Fe), and boron (B). The bias magnet 20 has dimensions of, for example, 4 mm×4 mm×2 mm, and the dimensions in the magnetization direction shown in FIG. 1 are, for example, 2 mm.

[0024] The bias magnet 20 applies a magnetic field in the longitudinal direction of the magnetostrictive members 11 and 12. By changing the strength of the magnetic field applied from the bias magnet 20 to the magnetoelectric conversion unit 10, the magnitude of the voltage generated in the piezoelectric member 13 is changed.

[0025] For example, the bias magnet 20 is disposed so as to face one end in the longitudinal direction of the magnetoelectric conversion unit 10 and so that the magnetization direction is parallel to the longitudinal direction of the magnetoelectric conversion unit 10. Note that an electromagnet can also be used as the excitation source.

[0026] In this case, it is possible to eliminate the rectifier circuit from the power storage unit 60a, and thus simplify the power storage unit 60a, although the rectifier circuit may be provided in the power storage unit 60a.

[0027] FIG. 9 is a schematic diagram showing the configuration of a magnetoelectric converter 2a according to a first modified example of the second embodiment. FIGS. 10(A) and 10(B) are schematic cross-sectional views showing the operation of the magnetoelectric converter 10 of the magnetoelectric converter 2a. The magnetoelectric converter 2a is a device that converts a magnetic field generated from a current line 100 as an object arranged at a position facing the lower surface of the magnetoelectric converter 10 into electricity and utilizes it. The magnetoelectric converter 2a is an electricity storage device. The magnetoelectric converter 2a shown in FIG. 9 differs from the magnetoelectric converter 1 shown in FIG. 1 in that it further includes a bias magnet 20a that applies a bias magnetic field B2 that contracts the magnetostrictive member 11 and expands the magnetostrictive member 12. As shown in Figure 9, in the magnetoelectric conversion device 2a, when no current flows through the current line 100, the magnetoelectric conversion unit 10 is curved by the bias magnetic field B2, and even when current flows through the current line 100, as shown in Figures 10(A) and (B), the magnetoelectric conversion unit 10 is only curved upwardly convex.

[0028] In this case, it is possible to eliminate the rectifier circuit from the power storage unit 60a, and thus simplify the power storage unit 60a, although the rectifier circuit may be provided in the power storage unit 60a.

[0029] FIG. 11 is a schematic diagram showing the configuration of a magnetoelectric converter 2b according to a second modification of the second embodiment. The magnetoelectric converter 2b is a device that converts a magnetic field generated from a current line 100 as an object arranged at a position facing the lower surface of the magnetoelectric converter 10 into electricity and utilizes it. The magnetoelectric converter 2b is an electricity storage device. The magnetoelectric converter 2b shown in FIG. 11 is different from the magnetoelectric converter 1 shown in FIG. 1 in that it further has a bias magnet 20b that applies a bias magnetic field B1 that contracts the magnetostrictive member 12. As shown in FIG. 11, in the magnetoelectric converter 2b, the magnetoelectric converter 10 is curved by the bias magnetic field B1 when no current flows through the current line 100. Even in this case, the curvature of the magnetoelectric converter 10 can be made only downward convex, and the electricity storage unit can be simplified.

[0030] FIG. 12 is a schematic diagram showing the configuration of a magnetoelectric conversion device 2c according to a third modification of the second embodiment. The magnetoelectric conversion device 2c is a device that converts a magnetic field generated from a current line 100 as an object arranged at a position facing the lower surface of the magnetoelectric conversion unit 10 into electricity and utilizes it. The magnetoelectric conversion device 2c is an electricity storage device. The magnetoelectric conversion device 2c shown in FIG. 12 is different from the magnetoelectric conversion device 1 shown in FIG. 1 in that it further has a bias magnet 20b that applies a bias magnetic field B1 that contracts the magnetostrictive member 12 and a bias magnet 20c that applies a bias magnetic field B2 that expands the magnetostrictive member 11. As shown in FIG. 12, in the magnetoelectric conversion device 2c, when no current flows through the current line 100, the magnetoelectric conversion unit 10 is curved by the bias magnetic fields B1 and B2. Even in this case, the curvature of the magnetoelectric conversion unit 10 can be made only downward convex, and the electricity storage unit can be simplified.

[0031] The positions and number of bias magnets and the direction of the magnetic field are not limited to the above example, and various modifications are possible.

[0032] Third Embodiment Fig. 13 is a schematic diagram showing the configuration of a magnetoelectric conversion device 3 according to embodiment 3. Fig. 14 is a schematic perspective view showing the configuration of a magnetoelectric conversion unit 10 of the magnetoelectric conversion device 3. The magnetoelectric conversion device 3 is a device that converts a magnetic field generated from a magnet 200, which is an object arranged at a position facing the lower surface of the magnetoelectric conversion unit 10, into electricity and utilizes it. The magnetoelectric conversion device 3 is a displacement measuring device that measures the displacement of the magnet 200 in the z direction. The displacement measuring device is a distance measuring device that measures the distance in the z direction or a position measuring device that measures the position in the z direction.

[0033] The magnetoelectric conversion device 3 includes magnetostrictive members 11 and 12 that are deformed by a magnetic field, a piezoelectric member 13 that is fixed to the magnetostrictive members 11 and 12 and curves due to the deformation of the magnetostrictive members 11 and 12, and a calculation unit 80 that receives a voltage output from the piezoelectric member 13 due to the curvature of the piezoelectric member 13 and performs calculations based on this voltage. The calculation unit 80 includes, for example, an A / D conversion circuit 81 that performs analog-to-digital (A / D) conversion of the output of the piezoelectric member 13 that curves in response to the magnetic field applied to the magnetostrictive members 11 and 12, and a calculation circuit 82 that calculates a displacement in the z direction (D1) based on the output of the A / D conversion circuit 81. The magnetostrictive members 11 and 12 are arranged to sandwich the piezoelectric member 13. The magnetostrictive members 11 and 12 are fixed to both sides of the piezoelectric member 13 by, for example, an adhesive. The calculation unit 80 may include a processor that operates by software.

[0034] 15(A) and (B) are schematic cross-sectional views showing the operation of the magnetoelectric conversion unit 10 of the magnetoelectric conversion device 3 according to the third embodiment. FIG. 15(A) shows a state in which the magnet 200 generating a magnetic field in the x direction is away from the magnetoelectric conversion unit 10, and almost no magnetic field is applied to the magnetostrictive members 11 and 12 (a weak magnetic field M1 is applied). At this time, the magnetoelectric conversion unit 10 is not curved. FIG. 15(B) shows a state in which the magnetostrictive member 11 expands (extends in the x direction) and the magnetostrictive member 12 contracts (shrinks in the x direction) when the magnet 200 approaches the magnetoelectric conversion unit 10 and a stronger magnetic field M1 than that in FIG. 15(A) is applied to the magnetostrictive members 11 and 12. At this time, the magnetoelectric conversion unit 10 is curved in a downward convex shape (i.e., an upward concave shape).

[0035] The magnetoelectric conversion device 3 can measure the amount of displacement (ie, distance or position) of the magnet 200 (ie, a member including the magnet 200) in the D1 direction.

[0036] Fourth Embodiment Fig. 16 is a schematic diagram showing the configuration of a magnetoelectric conversion device 4 according to embodiment 4. Fig. 17 is a schematic perspective view showing the configuration of a magnetoelectric conversion unit 10 of the magnetoelectric conversion device 4. The magnetoelectric conversion device 4 is a device that converts a magnetic field generated from a magnet 200, which is an object arranged at a position facing the lower surface of the magnetoelectric conversion unit 10, into electricity and utilizes it. The magnetoelectric conversion device 4 is a displacement measuring device that measures the displacement of the magnet 200 in the z direction (D1 direction). The displacement measuring device is a distance measuring device that measures the distance in the z direction or a position measuring device that measures the position in the z direction.

[0037] 18(A) and (B) are schematic cross-sectional views showing the operation of the magnetoelectric conversion unit 10 of the magnetoelectric conversion device 4. The magnetoelectric conversion device 4 shown in FIG. 16 differs from the magnetoelectric conversion device 3 shown in FIG. 13 in that it further includes a bias magnet 20a that applies a bias magnetic field B2. As shown in FIG. 18(A), in the magnetoelectric conversion device 4, the magnetoelectric conversion unit 10 is maintained in an uncurved state by the bias magnetic field B2, and as shown in FIG. 18(B), when the magnet 200 approaches the magnetoelectric conversion unit 10, the magnetoelectric conversion unit 10 is curved in a downward convex shape. Note that the bias magnet 20a desirably includes a mechanism that allows the distance between the magnetoelectric conversion unit 10 and the magnetoelectric conversion unit 10 or the position in the z direction relative to the magnetoelectric conversion unit 10 to be adjusted.

[0038] The magnetoelectric conversion device 4 can measure the amount of displacement (i.e., distance or position) of the magnet 200 (i.e., a member including the magnet 200) in the D1 direction. In addition, the sensitivity can be adjusted by adjusting the position of the bias magnet 20a.

[0039] Fifth Embodiment Fig. 19 is a schematic diagram showing the configuration of a magnetoelectric conversion device 5 according to embodiment 5. Fig. 20 is a schematic perspective view showing the configuration of a magnetoelectric conversion unit 10 of the magnetoelectric conversion device 5. The magnetoelectric conversion device 5 is a device that converts a magnetic field generated from a magnet 300 as an object arranged at a position facing the lower surface of the magnetoelectric conversion unit 10 into electricity for use. The magnetoelectric conversion device 5 is a displacement measuring device that measures the displacement of the magnet 300 in the x direction (D2 direction). The displacement measuring device is a distance measuring device that measures the distance in the x direction from a reference position, or a position measuring device that measures the position in the x direction.

[0040] 21(A) and (B) are schematic cross-sectional views showing the operation of the magnetoelectric conversion unit 10 of the magnetoelectric conversion device 5. The magnetoelectric conversion device 5 shown in FIG. 19 is different from the magnetoelectric conversion device 3 shown in FIG. 13 in that the magnet 300 has a portion that generates a magnetic field in the +z direction and a portion that generates a magnetic field in the opposite direction, that is, the -z direction, and the magnet 300 moves in the D2 direction. As shown in FIG. 21(A), in the magnetoelectric conversion device 5, the magnetic field M2 applied to the magnetostrictive members 11 and 12 becomes weaker depending on the displacement amount of the magnet 300 from the center position of the magnetoelectric conversion unit 10 in the z direction, and as shown in FIG. 21(B), the closer the magnet 300 is to the center position of the magnetoelectric conversion unit 10 in the z direction, the stronger the magnetic field M2 applied to the magnetostrictive members 11 and 12 becomes, and the magnetoelectric conversion unit 10 is curved in a downward convex shape. In this way, according to the fifth embodiment, the position of the object in the z direction can be measured.

[0041] Sixth Embodiment Fig. 22 is a schematic diagram showing the configuration of a magnetoelectric conversion device 6 according to embodiment 6. Fig. 23 is a schematic perspective view showing the configuration of a magnetoelectric conversion unit 10 of the magnetoelectric conversion device 6. The magnetoelectric conversion device 6 is a device that converts a magnetic field generated from a magnet 300, which is an object arranged at a position facing the lower surface of the magnetoelectric conversion unit 10, into electricity and utilizes it. The magnetoelectric conversion device 6 is a displacement measuring device that measures the displacement of the magnet 300 in the y direction (D2 direction). The displacement measuring device is a distance measuring device that measures the distance in the x direction or a position measuring device that measures the position in the x direction.

[0042] 24(A) and (B) are schematic cross-sectional views showing the operation of the magnetoelectric conversion unit 10 of the magnetoelectric conversion device 6. The magnetoelectric conversion device 6 shown in FIG. 22 differs from the magnetoelectric conversion device 5 shown in FIG. 19 in that it further includes a bias magnet 20a that applies a bias magnetic field B2. As shown in FIG. 24(A), in the magnetoelectric conversion device 6, the magnetoelectric conversion unit 10 is maintained in an uncurved state by the bias magnetic field B2, and as shown in FIG. 24(B), when the magnet 300 approaches the end of the magnetoelectric conversion unit 10, the magnetoelectric conversion unit 10 is curved in an upward convex shape. Note that the bias magnet 20a desirably includes a mechanism that allows the distance between the magnetoelectric conversion unit 10 and the bias magnet 20a or the position in the z direction relative to the magnetoelectric conversion unit 10 to be adjusted.

[0043] The magnetoelectric conversion device 6 can measure the amount of displacement (i.e., distance or position) of the magnet 300 (i.e., a member including the magnet 300) in the D2 direction. In addition, the sensitivity can be adjusted by adjusting the position of the bias magnet 20a.

[0044] Seventh Embodiment FIG. 25 is a schematic diagram showing the configuration of a magnetoelectric conversion device 7 according to the seventh embodiment. The magnetoelectric conversion device 7 is a device that converts a magnetic field generated from a magnet 300a as an object arranged at a position facing the lower surface of the magnetoelectric conversion unit 10 into electricity and utilizes it. The magnetoelectric conversion device 7 is a displacement measurement device that measures the displacement of the magnet 300a in the x direction (D2 direction). The displacement measurement device is, for example, a linear encoder. In the magnetoelectric conversion device 7 shown in FIG. 25, the magnet 300a has a part that generates a magnetic field in the +z direction and a part that generates a magnetic field in the opposite direction, that is, the -z direction, alternately, and the magnet 300a moves in the D2 direction. The number of magnet parts that configure the magnet 300a is not limited to four, and may be five or more. Thus, according to the seventh embodiment, it is possible to measure the position of the object in the z direction by the number of pulse signals that are encoder signals output from the piezoelectric member 13, and the configuration of the calculation unit 80 can be simplified.

[0045] Eighth Embodiment 26 is a schematic diagram showing the configuration of a magnetoelectric converter 8 according to embodiment 8. The magnetoelectric converter 8 is a device that converts a magnetic field generated from a magnet 200, which is an object disposed at a position facing the lower surface of the magnetoelectric converter 10, into electricity for use. The magnetoelectric converter 8 is a power storage device having a power storage unit 60b.

[0046] 26 differs from the magnetoelectric converter 2 according to the second embodiment (FIG. 7) in that it further includes a pickup coil 30 that is disposed so as to surround the magnetostrictive members 11, 12 and through which an induced current flows due to the deformation of the magnetostrictive members 11, 12, and in that the power storage unit 60b also stores in the storage battery power based on the induced current in the pickup coil 30. That is, in the magnetoelectric converter 8, the power storage unit 60b not only charges the storage battery with power based on the voltage generated by the curvature of the piezoelectric member 13, but also stores in the storage battery power based on the induced current flowing in the pickup coil 30 due to the displacement of the magnet 200 (for example, vibration in the D1 direction). The magnet 200 may be a magnet that displaces in the x direction (D2 direction) relative to the magnetoelectric converter 10.

[0047] With such a configuration, for example, it is possible to improve the electricity storage performance for mechanical energy.

[0048] As in the first embodiment, the power stored in the battery in the power storage unit 60b can be used to drive an environmental sensor (not shown) such as a temperature (humidity) sensor to monitor the environment around the current line 100, such as the temperature and humidity, and the power stored in the battery can be used to drive a wireless communication device to wirelessly transmit sensor information. In this case, it is possible to eliminate wiring from an external power source for the current sensor, the environmental sensor, and the wireless communication device, and also to eliminate wiring for transmitting detected data.

[0049] Ninth Embodiment 27 is a schematic diagram showing the configuration of a magnetoelectric converter 9 according to a ninth embodiment. The magnetoelectric converter 9 is a device that converts a magnetic field generated from a bias magnet 20 as an object arranged at a position facing an end of a magnetoelectric converter 10 into electricity for use. The magnetoelectric converter 9 is a power storage device having a power storage unit 60b.

[0050] The magnetoelectric conversion device 9 has a leaf spring 41 that supports the bias magnet 20 and the magnetoelectric conversion unit 10, and a weight 42 fixed to the leaf spring 41. The leaf spring 41 is supported by a device 40 as a vibrating body that applies vibration to the bias magnet 20 and the magnetoelectric conversion unit 10 via the leaf spring 41. The power generated by the change in the relative position of the bias magnet 20 and the magnetoelectric conversion unit 10 with respect to the pickup coil 30 is stored by the power storage unit 60b. The structure of the leaf spring 41 is not limited to the example shown in the figure, and may be other structures as long as it generates a change in the relative position of the bias magnet 20 and the magnetoelectric conversion unit 10 with respect to the pickup coil 30 (i.e., a change in the magnetic flux penetrating the pickup coil 30). The weight 42 is not an essential component. The device 40 may be a micro-vibrating body such as a machine in a factory that generates vibrations, a structure such as a bridge that vibrates due to the running of a vehicle, or a floor that vibrates due to walking, a machine tool shaft, a reciprocating structure such as an opening and closing window and an opening and closing door, etc.

[0051] The flat spring 41 may be an elastic body having another shape, such as a U-shaped spring or a coil spring.

[0052] According to such a configuration, for example, it is possible to improve the power storage performance for mechanical energy. Also, similarly to the eighth embodiment, it is possible to eliminate wiring from the power source, and also possible to eliminate wiring for transmitting detected data. [Explanation of symbols]

[0053] 1, 1a, 2, 2a to 2c, 8, 9 magnetoelectric conversion device (electricity storage device), 3 to 7 magnetoelectric conversion device (displacement measuring device), 11, 12 magnetostrictive member, 13 piezoelectric member, 20, 20a, 20b bias magnet, 30 pickup coil, 40 device, 60, 60a, 60b electricity storage unit, 61 rectifier circuit, 62 electricity storage circuit, 80 calculation unit, 81 A / D conversion circuit, 82 calculation circuit, 100 current line, 200 magnet, 300, 300a magnet.

Claims

1. A magnetoelectric conversion device that converts a magnetic field generated from an object into electricity, a magnetostrictive member that is deformed by the magnetic field; a piezoelectric member fixed to the magnetostrictive member and curved by deformation of the magnetostrictive member; a calculation unit that receives a voltage output from the piezoelectric member due to bending of the piezoelectric member, and calculates a position of the object based on the voltage; a bias magnet that applies a bias magnetic field to the magnetostrictive member to expand or contract the magnetostrictive member; having the magnetostrictive member and the piezoelectric member are laminated to form a magnetoelectric conversion unit, The magnetoelectric conversion unit is maintained in a curved or uncurved state by the expansion or contraction of the magnetostrictive member due to the bias magnetic field. A magnetoelectric conversion device characterized by:

2. The magnetostrictive member is a long plate-like member, The magnetostrictive member expands or contracts in the longitudinal direction of the magnetostrictive member due to the magnetic field.

2. A magnetoelectric conversion device according to claim 1.

3. The magnetostrictive member includes a first magnetostrictive member and a second magnetostrictive member disposed so as to sandwich the piezoelectric member, The first magnetostrictive member and the second magnetostrictive member are long and plate-like, With respect to the same magnetic field direction, one of the first magnetostrictive member and the second magnetostrictive member expands in the longitudinal direction of the magnetostrictive member, and the other of the first magnetostrictive member and the second magnetostrictive member contracts in the longitudinal direction.

2. A magnetoelectric conversion device according to claim 1.

4. the object includes a magnet; The calculation unit outputs a signal having a value corresponding to the distance from the magnet to the magnetostrictive member.

4. A magnetoelectric conversion device according to claim 1, wherein the magnetoelectric conversion device is a magnetoelectric conversion device.

5. the object includes a magnet; The calculation unit outputs a signal having a value corresponding to the position of the magnetostrictive member in the longitudinal direction relative to the magnetostrictive member.

4. A magnetoelectric conversion device according to claim 2 or 3.

6. The target object includes a plurality of magnets arranged side by side in a longitudinal direction of the magnetostrictive member, The calculation unit outputs an encoder signal having a value corresponding to a position in the longitudinal direction with respect to the magnetostrictive member.

4. A magnetoelectric conversion device according to claim 2 or 3.

7. The magnetostrictive member further includes a bias magnet that expands one of the first magnetostrictive member and the second magnetostrictive member in the longitudinal direction and contracts the other of the first magnetostrictive member and the second magnetostrictive member in the longitudinal direction.

4. The magnetoelectric conversion device according to claim 3.

8. A magnetoelectric conversion device that converts a magnetic field generated from an object into electricity and utilizes it, a magnetostrictive member that is deformed by the magnetic field; a piezoelectric member fixed to the magnetostrictive member and curved by deformation of the magnetostrictive member; a power storage unit that receives a voltage output from the piezoelectric member due to bending of the piezoelectric member and stores power based on the voltage in a storage battery; a bias magnet that applies a bias magnetic field to the magnetostrictive member to expand or contract the magnetostrictive member; having the magnetostrictive member and the piezoelectric member are laminated to form a magnetoelectric conversion unit, The magnetoelectric conversion unit is maintained in a curved or uncurved state by the expansion or contraction of the magnetostrictive member due to the bias magnetic field. A magnetoelectric conversion device characterized by:

9. The magnetostrictive member is a long plate-like member, The magnetostrictive member expands or contracts in the longitudinal direction of the magnetostrictive member due to the magnetic field.

9. A magnetoelectric conversion device according to claim 8.

10. The magnetostrictive member includes a first magnetostrictive member and a second magnetostrictive member disposed so as to sandwich the piezoelectric member, The first magnetostrictive member and the second magnetostrictive member are long and plate-like, With respect to the same magnetic field direction, one of the first magnetostrictive member and the second magnetostrictive member expands in the longitudinal direction of the magnetostrictive member, and the other of the first magnetostrictive member and the second magnetostrictive member contracts in the longitudinal direction.

9. A magnetoelectric conversion device according to claim 8.

11. The magnetostrictive member further includes a bias magnet that expands one of the first magnetostrictive member and the second magnetostrictive member in the longitudinal direction and contracts the other of the first magnetostrictive member and the second magnetostrictive member in the longitudinal direction.

11. A magnetoelectric conversion device according to claim 10.

12. The power storage unit includes a power storage circuit that stores power based on the voltage in the storage battery.

12. A magnetoelectric conversion device according to claim 8 or 11.

13. The power storage unit includes a rectifier circuit that rectifies the voltage output from the piezoelectric member, and a power storage circuit that stores power based on the rectified voltage in the storage battery.

12. A magnetoelectric conversion device according to claim 8, wherein the magnetoelectric conversion device is a magnetoelectric conversion device.

14. The magnetostrictive member further includes a pickup coil arranged to surround the magnetostrictive member, through which an induced current flows due to deformation of the magnetostrictive member. The power storage unit stores power based on the induced current in the storage battery.

12. A magnetoelectric conversion device according to claim 8, wherein the magnetoelectric conversion device is a magnetoelectric conversion device.

15. The object includes a current line or a magnet, The magnetostrictive member expands or contracts due to the current flowing through the current line or the displacement of the magnet.

12. A magnetoelectric conversion device according to claim 8, wherein the magnetoelectric conversion device is a magnetoelectric conversion device.

16. the object includes a magnet; The magnet is supported by a vibrating device.

15. A magnetoelectric conversion device according to claim 14.

17. 9. The magnetoelectric conversion device according to claim 1, wherein when the magnetoelectric conversion unit is maintained in a curved state, the magnetoelectric conversion unit is deformed to an uncurved state due to deformation of the magnetostrictive member caused by a magnetic field generated by the object.

18. 9. The magnetoelectric conversion device according to claim 1, wherein when the magnetoelectric conversion unit is maintained in an unbent state, the magnetoelectric conversion unit is deformed into a curved state due to deformation of the magnetostrictive member caused by a magnetic field generated by the object.

19. 9. The magnetoelectric converter according to claim 1, wherein the magnetoelectric converter is curved so as to be convex only in one direction of the lamination direction due to deformation of the magnetostrictive member caused by a magnetic field generated from the object.

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