WO2024089901A1 - Electric device - Google Patents

Abstract

[Problem] To provide an electric device that has a simpler structure than the prior art and is capable of driving a load unit by performing self-power generation for converting vibrations, displacement, etc., from external force into power. [Solution] The electric device 100A of the present disclosure comprises: an electromagnetic induction coil 12; an elastic body 20 that contains a magnetized magnetic powder body 22, generates a magnetic field penetrating the electromagnetic induction coil 12, and exhibits a change in the magnetic flux density of the magnetic field when being elastically deformed upon receiving external force; a rectification unit 91 that rectifies an induced current induced in the electromagnetic induction coil 12 due to the change in the magnetic flux density; and a load unit 92 that is operated by receiving power from the rectification unit 91.

Description

Electrical Equipment

This disclosure relates to self-powered electrical devices.

Conventional electrical devices of this type are known to generate electricity by using a rotating machine that is driven by an external force (see, for example, Patent Document 1).

JP2012-515860 (Fig. 4, claim 11)

However, the above-mentioned conventional electrical devices have a complicated structure due to the presence of a rotating machine, which can cause breakdowns. Therefore, this disclosure provides an electrical device that has a simpler structure than conventional devices and is capable of driving a load by generating its own electricity by converting vibrations, displacements, etc. from external forces into electricity.

One aspect of the present invention, which has been made to solve the above problems, is an electrical device that includes an electromagnetic induction coil, an elastic body that contains magnetized magnetic powder and generates a magnetic field that penetrates the electromagnetic induction coil and changes the magnetic flux density of the magnetic field when it undergoes elastic deformation due to an external force, a rectifier that rectifies the induced current induced in the electromagnetic induction coil due to the change in magnetic flux density, and a load that receives power from the rectifier and operates.

Circuit diagram of an electrical device according to a first embodiment of the present disclosure. Perspective view of an electrical device Side cross-sectional view of an electrical device Conceptual diagram of the power generation section (A) A conceptual diagram showing magnetic powder in a magnetic elastomer; (B) A conceptual diagram of a compressed magnetic elastomer. Flowchart showing a method for manufacturing a magnetic elastic body (A) A conceptual diagram showing the magnetization of a magnetic elastomer before compressive deformation, (B) A conceptual diagram showing the magnetization and induced current of a magnetic elastomer when it is compressed and deformed. (A) A conceptual diagram showing the magnetic field caused by a magnetic elastic body before compressive deformation and the magnetization of the magnetic elastic body. (B) A conceptual diagram showing the induced magnetic field and induced current generated in a coil and a circuit when a magnetic elastic body is compressed. (A) A conceptual diagram showing the magnetic field caused by a magnetic elastic body before compression deformation and the magnetization of the magnetic elastic body. (B) A conceptual diagram showing the induced magnetic field and induced current generated in two coils and a circuit when the magnetic elastic body is compressed. Circuit diagram of an electric device according to a second embodiment FIG. 13A is a conceptual diagram of an electric device according to a third embodiment; FIG. 13B is a partially cutaway side view of the electric device attached to a suspension; 13 is a conceptual diagram of an electric device according to a fourth embodiment. FIG. 13 is a side cross-sectional view of a floor structure including electrical equipment according to a fifth embodiment. FIG. 13 is a perspective view of an electric device according to a sixth embodiment; FIG. 13 is a perspective view of an electric device according to a seventh embodiment; FIG. 13A is a side cross-sectional view of an electric device according to an eighth embodiment; FIG. 13B is a side cross-sectional view of the electric device after bending; FIG. 13 is a perspective view of an electric device according to a ninth embodiment; Conceptual diagram of the test equipment A table showing the details and characteristics of the magnetic elastic bodies of each experimental example.

[First embodiment]
An electric device 100A according to an embodiment of the present disclosure will be described with reference to Figures 1 to 9. As shown in Figure 1, the electric device 100A according to the present embodiment has a power generation unit 10, a rectification unit 91, and a load unit 92.

The load unit 92 includes, for example, a wireless module 92A. The wireless module 92A is, for example, a modified RFID. Whereas an RFID tag receives power wirelessly and modulates an identification number onto a carrier wave for short-range wireless communication and transmits it wirelessly each time it receives power, the wireless module 92A receives power via a wire from the power generation unit 10 through the rectifier unit 91 and modulates an identification number onto a carrier wave for a specified wireless communication and transmits it each time it receives power. Examples of the specified wireless communication include long-distance wireless communication, Wi-Fi, infrared communication, and short-distance wireless communication.

In addition, the wireless module 92A may modulate information other than the identification number onto a carrier wave and transmit it wirelessly, or it may transmit only a radio wave of a specific frequency that does not contain any information without modulating information onto a carrier wave, so that the fact that the radio wave has been transmitted is itself information from the electrical device 100A.

The rectifier 91 is, for example, a known voltage doubler rectifier circuit, with the electromagnetic induction coil 12 of the power generation unit 10 (described below) connected to its input side, and the wireless module 92A described above connected to its output side. The induced current induced in the electromagnetic induction coil 12 is rectified by the rectifier 91 and applied to the wireless module 92A.

Note that, although a triple voltage rectifier circuit is illustrated as an example of the rectifier unit 91 shown in FIG. 1, an n-fold voltage rectifier circuit according to the desired voltage may be used, and in the second embodiment, a double voltage rectifier circuit is illustrated as an example.

The power generating unit 10 includes an electromagnetic induction coil 12, an elastic body 20 disposed inside the coil 12, and a telescopic case 30 that houses them. As shown in FIG. 2 and FIG. 3, the telescopic case 30 is structured such that a cylindrical body 31 with one end closed and the other end open is fitted with a cylindrical body 32 with one end closed and the other end open, the open ends of which are opposed to each other. The axial lengths of both the cylindrical bodies 31 and 32 are approximately the same, and the open ends of both the cylindrical bodies 31 and 32 are provided with return parts 31A and 32A that engage with each other to prevent separation. The telescopic case 30 can be changed between a maximum length state in which the return parts 31A and 32A engage with each other, and a minimum length state in which the open end of one cylindrical body 31 abuts against the bottom of the other cylindrical body 32. The telescopic case 30 in the minimum length state has an axial length that is, for example, approximately half that of the telescopic case 30 in the maximum length state.

A circuit case 33 housing the rectifier section 91 and load section 92 is fixed to the outer surface of the cylinder 31. The bottom wall end of one cylinder 31 is provided with a plurality of protrusions 31B that protrude laterally from a plurality of positions in the circumferential direction, and each of the protrusions 31B has an attachment hole 31C. The tip of the other cylinder 32 is provided with, for example, an adjustment mechanism 35. The adjustment mechanism 35 is provided with a support cylinder 35A that protrudes from the center of the outer surface of the bottom wall of the cylinder 32 and has a female screw section 35B on its inner surface, a shaft section 35D that has a male screw section 35C on its outer surface that screws into the female screw section 35B, and an abutment plate 35E rotatably attached to the tip of the shaft section 35D.

In this embodiment, the telescopic case 30 is made of a non-magnetic material such as resin or stainless steel, but the telescopic case 30 and the spacer 34 described later may be made of a magnetic material such as iron so that the telescopic case 30 forms a magnetic path together with the elastic body 20 described later. In this embodiment, the cylindrical bodies 31 and 32 are connected to each other via the elastic body 20 described later, and are non-rotatable, but a vertically long engagement groove may be provided on one of the cylindrical bodies 31 and 32, and a protrusion that engages with the engagement groove may be provided on the other to restrict the relative rotation of the cylindrical bodies 31 and 32.

As shown in FIG. 3, the electromagnetic induction coil 12 is fixed inside one of the cylinders 31 with an outer diameter and axial length that fit just inside the cylinder 31. A pair of lead wires 12A of the electromagnetic induction coil 12 are pulled out to the side of the cylinder 31 through a through hole 31D that penetrates the side wall of the cylinder 31 closest to the bottom wall. The pair of lead wires 12A are then taken into the circuit case 33 and connected to the rectifier 91. The pair of lead wires 12A bend as the expandable case 30 expands and contracts. The open end of the cylinder 32 has a notch 32B (see FIG. 2) formed to avoid interference with the pair of lead wires 12A.

The elastic body 20 is cylindrical and fits into the electromagnetic induction coil 12 through a gap, and is arranged on the concentric axis of the telescopic case 30. Both end faces are fixed to the bottom faces of the cylindrical bodies 31 and 32, for example, with an adhesive. In addition, a cylindrical spacer 34 having the same outer diameter as the elastic body 20 is arranged between one end face of the elastic body 20 and the bottom face of the cylindrical body 32 as necessary to adjust the compression ratio of the elastic body 20. Specifically, when the spacer 34 is not provided, the elastic body 20 in the telescopic case 30 is compressed to 1/2 in the same manner as the telescopic case 30 when the telescopic case 30 changes from the longest state to the shortest state. In contrast, if the spacer 34 is provided, the compression ratio of the elastic body 20 can be increased to any compression ratio of 1/2 or more. Note that FIG. 3 illustrates a structure in which the elastic body 20 equipped with the spacer 34 is compressed to 1/3.

The elastic body 20 is slightly compressed between the bottom surfaces of the cylindrical bodies 31 and 32 when the telescopic case 30 is in its longest position. This prevents rattling between the cylindrical bodies 31 and 32 when the telescopic case 30 is not receiving any external force.

In addition, the elastic body 20 is fixed to the cylindrical bodies 31 and 32 with an adhesive, but it does not have to be fixed. In addition, the bottom surfaces of the cylindrical bodies 31 and 32 and both end surfaces of the elastic body 20 may have projections and recesses that fit into each other to center the elastic body 20 relative to the expandable case 30.

The elastic body 20 is, for example, a foamed elastomer, and has magnetized magnetic powder 22 dispersed within it. In other words, the elastic body 20 is what is called a "magnetic elastic body." In the following explanation, in order to clearly distinguish between the single elastic body that is the main component of the elastic body 20 into which the magnetic powder 22 is mixed, and the elastic body 20 that contains the elastic body and the magnetic powder 22, the entire "elastic body 20" that contains the elastic body and the magnetic powder 22 is referred to as the "magnetic elastic body 20," and the single elastic body is referred to as the foamed elastomer 21 because it is a foamed elastomer, to clearly distinguish between the two.

The foamed elastomer 21 is a polyurethane elastomer foam and has an open cell structure or a semi-open cell structure. The foamed elastomer 21 has an expansion ratio of 1.4 to 6 times. The foamed elastomer 21 may be a rubber foam or a thermoplastic resin foam such as a polyolefin resin. It is preferable that the foamed elastomer 21 has an open cell structure or a semi-open cell structure as a whole from the viewpoint of moldability and ease of elastic deformation, but the open cell structure or semi-open cell structure may be a part of the foamed elastomer 21. By having at least a partial open cell structure, the foamed elastomer 21 can be prevented from shrinking (so-called shrinking) after molding. Furthermore, the foamed elastomer 21 in this embodiment has an expansion ratio of 1.4 to 6 times as described above, but it is more preferable that it is 1.7 to 5 times, and even more preferable that it is 2 to 4 times. Here, when the expansion ratio of the foamed elastomer 21 is 1.4 times or more, the cushioning properties are particularly good, and when the expansion ratio is 6 times or less, the moldability and durability are particularly good. Also, the above expansion ratio does not refer to the expansion ratio of the foamed elastomer 21 containing the magnetic powder 22, but to the expansion ratio of the foamed elastomer 21 alone.

The magnetic powder 22 is a neodymium-based magnetic powder, and the particle diameter of the magnetic powder 22 is 3 to 200 μm. The magnetic powder 22 is preferably made of a neodymium-based magnetic powder that has a strong magnetic force when made into a permanent magnet, but is not limited to neodymium-based magnetic powder and may be a known hard magnetic material such as a samarium-based magnetic powder, an alnico-based magnetic powder, or a ferrite-based magnetic powder. The shape of the particles 23 of the magnetic powder 22 is not limited, but specific examples include, for example, a scale-like, spherical, or needle-like shape. Furthermore, the particle diameter of the magnetic powder 22 in this embodiment is 3 to 200 μm as described above, but is more preferably 5 to 100 μm. By increasing the particle diameter of the magnetic powder 22, it is possible to increase the surface magnetic flux density of the magnetic elastic body 20. When the magnetic powder 22 is formed by surface-treating magnet particles, the particle diameter of the magnetic powder 22 can be increased to increase the proportion of magnetic components in the magnetic powder 22, and the surface magnetic flux density of the magnetic elastic body 20 can be further increased. In addition, it is preferable that the particle diameter of the magnetic powder 22 is 200 μm or less from the viewpoint of moldability and ease of deformation of the magnetic elastic body 20. In addition, when the particle diameter of the magnetic powder 22 is 200 μm or less, moldability is particularly good, and it is possible to further prevent the magnetic powder 22 from falling off the foamed elastomer 21. Furthermore, if the particle diameter of the magnetic powder 22 is less than 3 μm, workability is deteriorated, so it is preferable that the particle diameter of the magnetic powder 22 is 3 μm or more. The above particle diameter is measured by a sieving test in accordance with JIS Z 8815:1994.

In the magnetic elastic body 20 of this embodiment, the mass concentration (mass ratio) of the magnetic powder 22 to the foamed elastomer 21 is 40 to 80%, and the volume concentration (volume ratio) of the magnetic powder 22 to the foamed elastomer 21 is 1.0 to 3.5%. This makes it possible to easily elastically deform the magnetic elastic body 20 while increasing the change in magnetic flux density of the magnetic elastic body 20. The magnetic elastic body 20 preferably has a compression permanent set of 30% or less in accordance with JIS K 6262:2013 A method. The magnetic elastic body 20 preferably has a repeated compression set of 20% or less when compressed 50% 100,000 times at 1 Hz. These configurations provide good recovery after the foamed elastomer 21 is elastically deformed. As a result, even when the magnetic elastic body 20 is used in an application in which it is repeatedly compressed, the settling of the foamed elastomer 21 is reduced, making the magnetic elastic body 20 even more suitable for repeated use.

As shown in FIG. 5, the particles 23 of the magnetic powder 22 in the foamed elastomer 21 are magnetized so that their magnetic moments (more specifically, the composite magnetic moment within the particles 23) are aligned along the axial direction of the cylindrical magnetic elastic body 20, so that one end of the magnetic elastic body 20 in the axial direction becomes the north pole and the other end becomes the south pole as shown in FIG. 4. In more detail, some of the particles 23 of the magnetic powder 22 may have magnetic moments whose direction crosses the axial direction of the magnetic elastic body 20, but the composite magnetic moment obtained by combining the magnetic moments of the particles 23 of the magnetic powder 22 is aligned along the axial direction of the magnetic elastic body 20. Note that in FIG. 5(A) and FIG. 5(B) described later, the magnetization directions of the particles 23 of the magnetic powder 22 are indicated diagrammatically by arrows.

The structure of the electrical device 100A has been described above. The electrical device 100A is manufactured by the following method. That is, to manufacture the magnetic elastic body 20 as shown in FIG. 6, first, a first liquid is prepared by mixing polyol and isocyanate to form a prepolymer. Here, the first liquid is a prepolymer having an isocyanate group (NCO) at the end. Then, the magnetic powder 22 is mixed into the first liquid and uniformly dispersed (S11). Also, a second liquid containing a catalyst, a foaming agent, etc. is prepared (S11). Then, the first liquid and the second liquid are mixed to obtain a mixed liquid (S12). Here, the NCO% of the prepolymer having an isocyanate group at the end is preferably 3 to 7%, and in this embodiment, it is 6%. This makes it possible to obtain a magnetic elastic body 20 with excellent moldability and durability.

Next, the mixture is poured into a mold whose temperature has been adjusted in advance, and foamed and cured to form, for example, a cylindrical foamed molded body (S13). In this foamed molded body, the magnetic powder 22 is dispersed in the foamed elastomer 21. In addition, in the foamed molded body, the magnetic moment of each particle 23 of the magnetic powder 22 is randomly oriented. In the foaming and curing process of the mixture in the mold, the mold is closed and cured for a predetermined time (primary curing), and then the obtained foamed molded body is removed from the mold. The primary curing is performed, for example, at 60 to 120°C for 10 to 120 minutes. It is preferable to further perform secondary curing on the foamed molded body removed from the mold after the primary curing, and the secondary curing is performed, for example, at 90 to 180°C for 8 to 24 hours. In this embodiment, the elastic member in which the magnetic powder 22 is dispersed and arranged is a polyurethane elastomer, so that the time until the raw material hardens is short, and it is possible to harden the raw material before the magnetic powder 22 settles in the raw material. This makes it easy to uniformly disperse the magnetic powder 22. Therefore, even magnetic powder 22 with a particle diameter of 100 μm or more can be easily dispersed within the magnetic elastic body 20, making it possible to increase the magnetic flux density of the magnetic elastic body 20.

In addition, in this embodiment, the magnetic powder 22 is mixed into the first liquid and then mixed into the second liquid, so the magnetic powder 22 can be dispersed more uniformly within the foamed elastomer 21 than when the magnetic powder 22 is mixed into the second liquid and then mixed into the first liquid.

Next, the foamed molded body is magnetized (S14). In this process, the magnetic moments of the particles 23 of the magnetic powder 22 in the foamed molded body are aligned by applying an external magnetic field. In this embodiment, the external magnetic field is applied in the axial direction of the cylindrical foamed elastomer 21. Here, magnetization may be performed when the foamed molded body is in its natural length state without deformation, or when it is compressed in the axial direction relative to its natural length state (for example, compressed by 50%). In this manner, the magnetic elastomer body 20 is obtained from the foamed molded body.

Furthermore, it is particularly preferable that the magnetic elastomer 20 has a magnetic flux density (surface magnetic flux density) that is 5% or more greater than that at its natural length when compressed 10% in the axial direction. Such a magnetic elastomer 20 can be manufactured, for example, by compressing a foamed elastomer 21 having magnetic powder 22 dispersed therein (for example, compressed to 50%) and magnetizing the magnetic powder 22 in the direction of compression.

The magnetic elastic body 20 manufactured as described above is assembled to the telescopic case 30 as follows. That is, the cylindrical bodies 31 and 32 of the telescopic case 30 are prepared in a separated state. Then, the electromagnetic induction coil 12 is fixed to one cylindrical body 31 with the pair of lead wires 12A of the electromagnetic induction coil 12 pulled out from the through hole 31D, and the magnetic elastic body 20 with adhesive applied to both end faces is placed inside the electromagnetic induction coil 12 and fixed to both bottom faces of the cylindrical bodies 31 and 32. At this time, if necessary, a spacer 34 is fixed between one end face of the magnetic elastic body 20 and the bottom face of the cylindrical body 32 with an adhesive. Then, one cylindrical body 31 is deformed so as to narrow the open end and is pushed inside the other cylindrical body 32, and one cylindrical body 31 elastically returns to its original state so that the return parts 31A and 32A of both cylindrical bodies 31 and 32 engage with each other.

Next, the pair of lead wires 12A of the electromagnetic induction coil 12 is connected to the rectifier 91, and the rectifier 91 is connected to the load 92, and the rectifier 91 and the load 92 are stored in the circuit case 33. This completes the manufacture of the electrical device 100A.

The manufacturing method of the electric device 100A of this embodiment has been described above. Next, the effect of the electric device 100A will be described. As shown in FIG. 3, the electric device 100A is set in the gap between a pair of opposing members 201, 202 whose mutual distance may vary, and is used to detect the deformation, operation, etc. of the pair of opposing members 201, 202. For this purpose, the electric device 100A is arranged so that the axial direction of the telescopic case 30 (which is also the axial direction of the electromagnetic induction coil 12 and the magnetic elastic body 20) faces the opposing direction of the pair of opposing members 201, 202. Then, for example, when the distance between the pair of opposing members 201, 202 is in the normal state, the adjustment mechanism 35 is adjusted so that the telescopic case 30 is in a desired state. Specifically, when detecting both the case where the pair of opposing members 201, 202 move away from the normal state and the case where they approach each other, the adjustment mechanism 35 is adjusted so that the telescopic case 30 is in a compressed state that is approximately half of the maximum state. In addition, when it is desired to detect only that the pair of opposing members 201, 202 have come closer to each other from the normal state, the adjust mechanism 35 is adjusted so that the telescopic case 30 is slightly compressed between the pair of opposing members 201, 202 in the normal state, or the abutment plate 35E of the adjust mechanism 35 is slightly separated from one of the opposing members 202. In addition, in order to prevent the electrical device 100A from shifting laterally from the pair of opposing members 201, 202, it is preferable to fix the telescopic case 30 to one of the magnetic elastic bodies 201, for example, by tightening a bolt passed through the mounting hole 31C of the telescopic case 30 into a screw hole of one of the magnetic elastic bodies 201, as necessary.

As described above, when the electrical device 100A is set between the pair of opposing members 201, 202 and the distance between the pair of opposing members 201, 202 changes, the magnetic elastic body 20 expands and contracts in the axial direction together with the expandable case 30. This changes the density of the magnetic flux that penetrates the electromagnetic induction coil 12 out of the magnetic flux of the magnetic field produced by the magnetic elastic body 20, generating an induced current I. In other words, power is generated in the power generation unit 10.

The mechanism by which the power generation occurs is considered to be as follows: In other words, in the axial direction of the electromagnetic induction coil 12, if the magnetic flux density in the magnetic elastic body 20 is Bz, the external magnetic field is Hz, the magnetization of the magnetic elastic body 20 is Mz, and the magnetic permeability of a vacuum is μ0, then:
Bz = μ0 · Hz + Mz ... (A)
Regarding the magnetization Mz, if the average value of the magnetic moment of the particles 23 of the magnetic powder 22 in the axial direction of the electromagnetic induction coil 12 is mz, and the number of the particles 23 of the magnetic powder 22 per unit volume of the magnetic elastic body 20 is n, then
Mz = n mz ... (B)
It is known that the relationship

Here, the magnetic elastic body 20 is made by mixing the foamed elastomer 21 with the magnetic powder 22, so when it is compressed in the axial direction, the bubbles of the foamed elastomer 21 are crushed, and when it is stretched, the bubbles expand, and it expands and contracts while suppressing changes in radial size. When the magnetic elastic body 20 is compressed in the axial direction of the electromagnetic induction coil 12 (Figure 5 (B)), the distribution density of the particles 23 of the magnetic powder 22 in the magnetic elastic body 20 increases (i.e., n in the relational expression (B) becomes larger), and it is thought that the magnetization Mz increases, and when it is stretched, the magnetization Mz decreases.

In particular, when the magnetic elastic body 20 is magnetized in a compressed state in which it is shrunk relative to its natural length, when the magnetic elastic body 20 is compressed in the axial direction of the electromagnetic induction coil 12, the magnetic moment of the particles 23 of the magnetic powder 22 will be aligned in the axial direction of the electromagnetic induction coil 12 compared to when it is in its natural length, and it is believed that the average value mz of the magnetic moment will be larger.

In addition to the effect of the change in distribution density of the magnetic powder 22 described above, the increase or decrease in the average value mz of the magnetic moment is considered to further increase the change in magnetization Mz. In detail, when the magnetic elastic body 20 is compressed, the magnetization Mz is considered to be particularly large when it reaches the compression amount at the time of magnetization (i.e., the compression amount at which the magnetic moment mz of the magnetic powder 22 is most aligned in the axial direction of the magnetic elastic body 20). When the magnetization Mz increases, the magnetic flux density Bz in the magnetic elastic body 20 increases according to the above relational expression (A), and the magnetic flux penetrating the electromagnetic induction coil 12 increases. When the magnetic elastic body 20 expands, the opposite phenomenon occurs to when it is compressed. It is considered that the induced current I flows through the electromagnetic induction coil 12 so as to generate a magnetic field H' in a direction that cancels out these changes in magnetic flux (downward in FIG. 7). In FIG. 7 and FIG. 8, the induced current I and the magnetic field H' generated by the induced current I are indicated by gray arrows.

Figures 8(A) and 8(B) show an example in which the size of the portion of the magnetic elastic body 20 that is placed inside the electromagnetic induction coil 12 changes due to deformation of the magnetic elastic body 20. In this case, as will be explained below, it is considered that the magnetic flux penetrating the electromagnetic induction coil 12 changes due to factors other than the change in magnetization of the magnetic elastic body 20.

In the examples of Figures 8(A) and 8(B), the magnetic elastic body 20 is compressed in the axial direction of the electromagnetic induction coil 12. In this case, a region R is provided in the electromagnetic induction coil 12 where the magnetic elastic body 20 exists before deformation of the magnetic elastic body 20 (Figure 8(A)), but where the magnetic elastic body 20 does not exist after deformation (Figure 8(B)). In this region R, the magnetic flux changes before and after deformation of the magnetic elastic body 20, so it is considered that a magnetic field H" is generated in region R to cancel out this change in magnetic flux. This magnetic field H" can be in the opposite direction to the magnetic field H' due to the change in distribution density of the particles 23 of the magnetic powder 22 in the magnetic elastic body 20 described above, but these magnetic fields do not always have the same magnitude during the process of deforming the magnetic elastic body 20, so it is considered that a change in the magnetic flux penetrating the electromagnetic induction coil 12 occurs, and an induced current I can be generated in the electromagnetic induction coil 12. When magnetic fields H' and H" are generated in opposite directions, an electromagnetic induction coil 12V may be disposed surrounding region R as shown in FIG. 9. In this way, by generating the induced current generated by magnetic field H' and the induced current generated by magnetic field H" in separate circuits, it is possible to prevent these induced currents from cancelling each other out. The case in which the magnetic elastic body 20 expands is similar to the case in which the magnetic elastic body 20 is compressed.

As described above, the induced current I generated by the power generation unit 10 is rectified by the rectifier unit 91 and received by the load unit 92. Then, a wireless signal including the identification number information is output from the wireless module 92A of the load unit 92. This makes it possible to receive the wireless signal from the electrical device 100A with a wireless terminal located away from the electrical device 100A and monitor the load and behavior of the pair of opposing members 201, 202.

In addition, by setting multiple electrical devices 100A of this embodiment in gaps between the bridge girders and the bridge body of an viaduct, gaps under the floors of buildings with seismic isolation structures, gaps under the road surface, etc., and storing the installation location and identification number of each electrical device 100A in association with each other, and monitoring wireless signals from multiple electrical devices 100A with a monitoring terminal, it is possible to monitor the behavior of viaducts and buildings due to typhoons, earthquakes, etc., and the presence or absence of abnormalities.

As described above, the electrical device 100A of this embodiment generates its own power through electromagnetic induction by changing the magnetic flux density of the magnetic field penetrating the electromagnetic induction coil 12 through the deformation of the magnetic elastic body 20, so the power generation structure can be simplified compared to electrical devices that generate power using conventional rotating machines.

Furthermore, since the magnetic elastic body 20 is a foamed elastomer, it can be expanded and contracted with a larger stroke than when the magnetic elastic body is formed from an elastic body such as a general resin or metal containing a non-foamed elastomer. And since the magnetic elastic body 20 can generate electricity by changing the magnetic flux density through deformation with a large stroke, it is possible to generate more electricity per stroke than one that can only change the magnetic flux density with a short stroke. Also, if the same amount of electricity is to be obtained as one that can only change the magnetic flux density with a short stroke, it is possible to generate electricity by reversing the direction of the magnetic flux in a long period. In other words, the power generation unit 10 of the electric device 100A of this embodiment makes it possible to generate low-frequency alternating current, which makes it easy to achieve impedance matching between the power generation unit 10 and the rectification unit 91, load unit 92, etc. connected to it. Furthermore, as described above, the magnetic elastic body 20 is able to suppress changes in radial size due to expansion and contraction, which reduces interference with the electromagnetic induction coil 12 and narrows the clearance between the magnetic elastic body 20 and the electromagnetic induction coil 12 outside it, improving power generation efficiency. Also, because the magnetic elastic body 20 is a foamed elastomer, it is less likely to break and is easier to handle.

[Second embodiment]
The electric device 100B of this embodiment is shown in FIG. 10, and the configuration of the rectifier 91V and the load 92V is different from that of the first embodiment. That is, the rectifier 91V is a double voltage rectifier circuit, and a secondary battery 91A is connected between a pair of output terminals of the rectifier 91V. The load 92V is provided with a detection circuit 92B and a wireless circuit 92C, and a current detection unit 92D for detecting an induced current flowing through the electromagnetic induction coil 12 is connected to the load 92V. Furthermore, the detection circuit 92B includes an A/D converter and a microcomputer. Then, based on the induced current generated by the electromagnetic induction coil 12, detection data for identifying an external force received by the electric device 100B is generated, and the detection data is wirelessly transmitted by the wireless circuit 92C. In addition, various types of detection data can be used, such as FFT data, spectrum data, and peak value data included in the waveform of the induced current.

In the electric device 100B of this embodiment, detection data for identifying an external force is generated based on the induced current generated in the power generation unit 10, and then wirelessly transmitted, making it possible to collect data at a remote location far from the electric device 100B that is less susceptible to noise caused by wireless transmission. In addition, the provision of the secondary battery 91A stabilizes the power supply to the load unit 92V.

[Third embodiment]
11, an electric device 100C according to a third embodiment of the present disclosure is mounted on a vehicle 60 and is intended to charge a battery 51 of the vehicle 60. Only configurations that differ from the first and second embodiments will be described below.

The power generating unit 10 of the electric device 100C of this embodiment is attached to the suspension 61 of the vehicle 60. The suspension 61 of the vehicle 60 has a shock absorber 62 and a suspension spring 63, as shown in FIG. 11(B). The suspension spring 63 is sandwiched between a flange 65T that protrudes outward from the cylinder 65 of the shock absorber 62 and the vehicle body 60B. The magnetic elastic body 20V included in the power generating unit 10 of the electric device 100C is cylindrical and fitted into the piston rod 64 of the shock absorber 62, functioning as a bound stopper. That is, when the shock absorber 62 contracts, the magnetic elastic body 20V is compressed between the cylinder 65 and the vehicle body 60B, thereby serving to suppress the bounding of the vehicle 60.

The electromagnetic induction coil 12 of the power generation unit 10 of the electrical device 100C is disposed inside the suspension spring 63 so as to surround the magnetic elastic body 20V, and its upper end is fixed to the vehicle body 60B. When the magnetic elastic body 20V expands and contracts, an induced current flows in the electromagnetic induction coil 12, generating electricity.

The rectifier 91W of the electrical device 100C boosts the power generated by the power generator 10 to a voltage required to charge the battery 51. The output of the power generator 10 is then applied to the battery 51, which corresponds to the load of the electrical device 100C, through the rectifier 91W, thereby charging the battery 51.

In the above embodiment, an automobile is used as an example of the vehicle 60, but the present invention may also be applied to the suspension of a motorcycle, train, or other vehicle. Examples of automobiles include electric vehicles, hybrid vehicles, plug-in hybrid vehicles, and other electrically powered vehicles.

[Fourth embodiment]
12, the electric device 100D of the fourth embodiment has a power generating unit 10 similar to that of the electric device 100C of the third embodiment, a rectifying unit 91V similar to that of the electric device 100B of the second embodiment, and a detection circuit 92B as a load unit. Detection data generated by the detection circuit 92B is provided to the control device 86 of the vehicle 60. The control device 86 determines the presence or absence of an abnormality, such as overloading of the vehicle 60 or a failure of the suspension 61, based on the provided detection data, and when an abnormality is detected, turns on a warning light 85 to notify the driver of the abnormality.

In the above embodiment, the vehicle 60 is provided with the electrical device 100D, and an abnormality related to the vehicle 60 is detected. However, for example, the electrical device 100D may be provided in a tank or pipe in a factory plant, and an abnormality in the tank or pipe may be detected.

[Fifth embodiment]
The electric device 100E of this embodiment is shown in Fig. 13(A) and Fig. 13(B) and is incorporated in a floor structure 71 of a building or vehicle. Specifically, the floor structure 71 has a structure in which a floor panel 73 is laid on a base 72, and a plurality of cushioning materials 78 are laid between the base 72 and the floor panel 73. When a load is applied to the floor panel 73, the cushioning materials 78 are elastically deformed. One or a part of the plurality of cushioning materials 78 is a magnetic elastic body 20W, and an electromagnetic induction coil 12 is provided so as to surround the magnetic elastic body 20W. The electric device 100E also has a rectifier unit and a wireless module similar to those of the first embodiment housed in a circuit case 33.

Sixth Embodiment
The electric device 100F of this embodiment is shown in FIG. 14, and the magnetic elastic body 20 is twisted when subjected to an external force. Specifically, the electric device 100F has a structure in which the adjustment mechanism 35 is removed from one of the cylindrical bodies 32 of the expandable case 30 of the electric device 100A of the first embodiment, and a twist case 30V having a plurality of protrusions 31B similar to those of the other cylindrical body 32 is provided with the magnetic elastic body 20 and the electromagnetic induction coil 12 of the electric device 100A of the first embodiment. The twist case 30V is attached to a pair of relatively rotating members or a shaft that receives a load torque. As a result, when an external force as a load torque is received, the pair of cylindrical bodies 31 and 32 rotate relatively, and the magnetic elastic body 20 is twisted. In addition, the magnetic elastic body 20 is, for example, arranged in a magnetic field oriented in the axial direction of the magnetic elastic body 20 in a twisted state, and the magnetic powder 22 is magnetized. The other structure is similar to that of the electric device 100A of the first embodiment.
In this electric device 100F, when the magnetic elastic body 20 is twisted in one direction, the direction of the magnetic moment of the magnetic powder 22 is aligned in the direction penetrating the electromagnetic induction coil 12, and when the magnetic elastic body 20 is twisted in the other direction, the direction of the magnetic moment of the magnetic powder 22 is aligned or varies in a direction different from the direction penetrating the electromagnetic induction coil 12. As a result, the density of the magnetic flux penetrating the electromagnetic induction coil 12 changes with the twisting deformation of the magnetic elastic body 20, generating power in the power generation unit 10, and a wireless signal is transmitted from the wireless module 92A of the load unit 92 in response to that power.

[Seventh embodiment]
The electric device 100G of this embodiment is shown in Fig. 15 and includes a twist case 30W in which a screwing mechanism is added to the twist case 30V of the electric device 100F of the sixth embodiment. Specifically, the outer surface of one cylindrical body 31 of the twist case 30W is provided with an engagement portion 31M having a groove structure or a ridge structure extending in a spiral shape, and the inner surface of the other cylindrical body 32 is provided with an engagement portion (not shown) that screws into the engagement portion 31M. As a result, when the cylindrical bodies 31 and 32 of the twist case 30W rotate relative to each other, the magnetic elastic body 20 is twisted and expanded/contracted. As a result, an induced current is induced in the electromagnetic induction coil 12.

[Eighth embodiment]
The electric device 100H of this embodiment is shown in Fig. 16. As shown in Fig. 16(A), the power generating unit 10 of the electric device 100H includes a cylindrical magnetic elastic body 20 that is fitted exactly to the shaft 203, which is the object of bending deformation detection, and an electromagnetic induction coil 12 that is fitted to the outside of the magnetic elastic body 20. As shown in Fig. 16(B), the magnetic elastic body 20 and the electromagnetic induction coil 12 are bent and deformed together with the shaft 203. In addition, the electric device 100H includes, for example, a rectifier unit 91 and a wireless module 92A similar to those of the electric device 100A of the first embodiment, housed in a circuit case 33. As the magnetic elastic body 20 is bent and deformed in accordance with the bending deformation of the shaft 203, the magnetic flux density penetrating the electromagnetic induction coil 12 changes, and power is generated in the power generating unit 10, and a wireless signal is transmitted from the wireless module 92A of the load unit 92 in response to the power.

[Ninth embodiment]
The electric device 100I of this embodiment is shown in Fig. 17 (A) and has a structure in which a pair of non-magnetic disks 39 are opposed to each other, and a plurality of magnetic elastic bodies 20 are connected in parallel between the pair of disks 39. Specifically, the plurality of magnetic elastic bodies 20 are, for example, cylindrical, and the central axis of each magnetic elastic body 20 is disposed at a position that divides an imaginary circle concentric with the central axis of the pair of disks 39 into a plurality of equal parts in a portion inside the outer edge of the pair of disks 39, and each magnetic elastic body 20 is fixed to the pair of disks 39 by an adhesive applied to both end faces of each magnetic elastic body 20. A plurality of mounting holes 39A are formed in the outer edge of the pair of disks 39.

Furthermore, an electromagnetic induction coil 12 is fitted to the outside of each magnetic elastic body 20. A plurality of rectifiers 91 and wireless modules 92A described in the first embodiment are provided corresponding to the plurality of electromagnetic induction coils 12 and are housed in the circuit case 33. Each time an induced current of a predetermined magnitude flows through each electromagnetic induction coil 12, a wireless signal including information of the unique identification number is transmitted from the wireless module 92A corresponding to each electromagnetic induction coil 12.

In the electric device 100I of this embodiment, a pair of disks 39 is fixed to the object to be detected. Then, power is generated in the multiple electromagnetic induction coils 12 in response to the behavior of the pair of disks 39 moving closer to and farther away from each other, the behavior of one disk 39 tilting in any direction relative to the other disk 39, and the behavior of the other disk 39 rotating around its central axis relative to the first disk 39, and a wireless signal corresponding to the power generation state is output.

Also, as shown in FIG. 17(B), by preparing an additional part 38 having a support 38A rising from the center of a disk 38C and a mass 38B at its tip, and then stacking and fixing the disk 38C of the additional part 38 on one of the disks 39 of the electrical device 100I, and fixing the other disk 39 to a building, vehicle, the ground, etc., it is possible to detect vibrations, etc., received by the electrical device 100I.

[Confirmation experiment]
It was confirmed by an experiment that power generation was performed by the electromagnetic induction coil 12 and the magnetic elastic body 20 described in the first embodiment. Specifically, the induced electromotive force generated in the electromagnetic induction coil 12 was confirmed as a substitute value for the induced current I.

I. Configuration of the Electromagnetic Induction Device The electromagnetic induction coil 12 was made of copper wire, with a coil winding diameter (inner diameter) of 36 mm (36Φ), an axial length of 70 mm, a wire diameter of 0.5 mm, a number of turns of 1395, and a resistance of 13 Ω. The magnetic elastic body 20 was made by dispersing neodymium-based magnetic powder in a polyurethane foam elastomer 21. The neodymium-based magnetic powder used had different particle sizes (5 μm and 100 μm). The magnetic elastic body 20 was cylindrical, with a diameter of 23 mm and an axial length of 23 mm. The magnetization conditions for the magnetic elastic body 20 were 8 Tesla for 3 seconds. The magnetic elastic body 20 was magnetized in a natural length state and in a 50% compressed state in the axial direction. In this experiment, the magnetic elastic body 20 was arranged coaxially with the electromagnetic induction coil 12, and the magnetic elastic body 20 was arranged so that its center position coincided with that of the electromagnetic induction coil 12 in its natural length state. The magnetic elastic body 20 was entirely contained within the electromagnetic induction coil 12, and was arranged so that its axial direction was the up-down direction, and the magnetic elastic body 20 was elastically deformed by compressing it from one end side in the axial direction (from below).

II. Details of the Magnetic Elastic Body of Each Experimental Example The details of the raw materials of the magnetic elastic body 20 are as follows.

(1) First Liquid Polyol: polyester polyol (molecular weight: 2000, number of functional groups: 2, hydroxyl value: 56 mgKOH/g, product name: "Polylite OD-X-102", manufactured by DIC Corporation Isocyanate: 1,5-naphthalene diisocyanate (NCO%: 40%, product name: "Cosmonate ND", manufactured by Mitsui Chemicals, Inc.)
Neodymium-based magnetic powder: (1) MQFP (5 μm), manufactured by Magnequench Co., Ltd. (2) MQFP (100 μm), manufactured by Magnequench Co., Ltd.

(2) Second liquid Catalyst: Amine catalyst, product name: "Addocat PP", manufactured by Rhein Chemie Japan Co., Ltd. Foaming agent: Mixture containing castor oil and water, product number: "Advade SV" (weight ratio of castor oil to water: 50:50), manufactured by Rhein Chemie Japan Co., Ltd.

In addition, in this experiment, magnetic elastic bodies 20 with different expansion ratios of the foamed elastomer 21, compounding ratios and particle sizes of the neodymium magnetic powder, and magnetization methods were used (Experimental Examples 1 to 5). The magnetization conditions and characteristic values of the magnetic elastic bodies 20 in each experimental example are as shown in Figure 19.

Figure 19 shows the details and characteristics of the foamed elastomers of Experimental Examples 1 to 5. In Experimental Example 1, the foamed elastomer 21 is magnetized in its natural length state with a foaming ratio of 2 times, the particle diameter of the neodymium magnetic powder is 5 μm, the mass ratio is 50 mass%, and the volume ratio is 3.3 volume%. In Experimental Example 2, the foaming ratio of the foamed elastomer 21 is 4 times, the volume ratio of the neodymium magnetic powder is 1.6 volume%, and the rest is the same as Experimental Example 1. In Experimental Example 3, the mass ratio of the neodymium magnetic powder is 60 mass%, the volume ratio is 3.9 volume%, and the rest is the same as Experimental Example 1. In Experimental Example 4, the elastomer is magnetized in a 50% compressed state in the axial direction, and the rest is the same as Experimental Example 3. In Experimental Example 5, the particle diameter of the neodymium magnetic powder is 100 μm, and the rest is the same as Experimental Example 3.

III. Test Method (1) Density and Expansion Ratio of Foamed Elastomer The expansion ratio of the foamed elastomer 21 was calculated by preparing a test sample of a cylindrical magnetic elastomer 20 having a diameter of 23 mm and an axial length (thickness) of 23 mm from the first liquid and the second liquid not containing neodymium-based magnetic powder, measuring the density based on JIS K6268:1998, and calculating the expansion ratio from the density.

(2) Mass ratio and volume ratio of neodymium-based magnetic powder The mass ratio of the neodymium-based magnetic powder was obtained by measuring the mass of the neodymium-based magnetic powder relative to the mass of the first liquid using a balance. The volume ratio of the neodymium-based magnetic powder was calculated using the following formula from the mass ratio of the neodymium-based magnetic powder, the density of the neodymium-based magnetic powder, and the density of the foamed elastomer 21. Here, the density of the neodymium-based magnetic powder was set to 7.6 g/ ^cm3 .
Volume ratio of neodymium-based magnetic powder (%) = (mass ratio of neodymium-based magnetic powder × density of foamed elastomer) / (density of neodymium-based magnetic powder)

(3) Compression Set The compression set was measured by preparing a test sample of the magnetic elastomer 20 having a diameter of 13 mm and a thickness of 6.3 mm, in accordance with JIS K 6262:2013 Method A (small test piece, 70°C x 22 hours, 25% compression).

(4) Repeated compression strain The repeated compression strain was calculated by compressing a test sample of the magnetic elastic body 20 having a diameter of 23 mm and an axial length (thickness) of 23 mm in the axial direction by 50% of the natural length (original thickness) at 1 Hz (1 time/second) 100,000 times, measuring the change in thickness before and after the repeated compression test, and calculating it from the following formula. Note that this measurement was performed at room temperature (23°C).
Repeated compression strain (%)=(thickness before compression test−thickness after compression test)/(thickness before compression test)×100

(5) Surface magnetic flux density The surface magnetic flux density was obtained by preparing a test sample of the magnetic elastic body 20 having a diameter of 23 mm and an axial length (thickness) of 23 mm, measuring the magnetic flux density at the center of the upper and lower surfaces, which are both end surfaces in the axial direction, 10 times each (total of 20 times) using a gaussmeter ("MG-601", manufactured by Magna), and calculating the average value. The surface magnetic flux density was also measured for the magnetic elastic body 20 in a natural length state and in a compressed state compressed in the axial direction by 10%, 25%, and 50% from the natural length state, and the rate of change in the surface magnetic flux density in each compressed state relative to the natural length state was calculated.

(6) Amount of power generation The amount of power generation was evaluated by vibrating and deforming the magnetic elastic body 20 so as to repeatedly compress and restore in the axial direction of the electromagnetic induction coil 12 using a test device 40 shown in Fig. 18, and measuring the voltage between both ends of the electromagnetic induction coil 12. The conditions for the vibration deformation of the magnetic elastic body 20 were nine conditions consisting of combinations of three levels of compression ratio (stroke amount) and three levels of frequency, and the voltage was measured for each condition. Specifically, the amplitude levels were 6 mm, 8 mm, and 10 mm (displacement amount), and the frequency levels were 1 Hz, 5 Hz, and 10 Hz.

Details of the test device 40 are as follows. The test device 40 has a piston 41 and a fixed member 42 inside the electromagnetic induction coil 12, which sandwich the magnetic elastic body 20 in the axial direction of the electromagnetic induction coil 12. The piston 41 receives power from a driving source 43 and vibrates in the axial direction of the electromagnetic induction coil 12, vibrating and deforming the magnetic elastic body 20. The distance between the fixed member 42 and the piston 41 is set so that it is the same as the natural length of the magnetic elastic body 20 when the piston 41 is farthest from the fixed member 42 during the vibration stroke. That is, in this experiment, the fixed member 42 and the piston 41 are always in contact with the magnetic elastic body 20.

In addition, both ends of the electromagnetic induction coil 12 are connected to an oscilloscope 44, which displays the induced electromotive force generated in the electromagnetic induction coil 12. Furthermore, the test device 40 is provided with a laser displacement meter 45 for detecting the vibration of the piston 41. A signal related to the amplitude, frequency, etc. of the piston 41 is output from the laser displacement meter 45 to the oscilloscope 44 via an amplifier unit 46, making it possible to confirm the amplitude and frequency of the vibration of the piston 41 on the oscilloscope 44.

IV. Test Results In all of Experimental Examples 1 to 5, the foamed elastomer 21 was made of a polyurethane elastomer, and thus the compression set was good, being 21 to 25% and the repeated compression set being 13 to 18%.

The surface magnetic flux densities in the natural length state of Experimental Examples 1 to 3 were 9.2 mT, 4.6 mT, and 10.3 mT, respectively, with the surface magnetic flux density being higher as the volume ratio of neodymium-based magnetic powder increased.The surface magnetic flux densities in the natural length state of Experimental Examples 3 and 5 were 10.3 mT and 14.6 mT, respectively, and it can be seen that the surface magnetic flux density is higher as the particle diameter of the neodymium-based magnetic powder increases. The surface magnetic flux density in the natural length state of Experimental Example 3 and Experimental Example 4 was 10.3 mT and 9.2 mT, respectively, and Experimental Example 3 was larger, but the surface magnetic flux density in the 10%, 25%, and 50% compressed states was 10.5 mT and 9.9 mT, 10.7 mT and 10.6 mT, and 10.9 mT and 12.6 mT, respectively, and the rate of change was 1.9% and 7.6%, 3.9% and 15.2%, and 5.8% and 37.0, respectively. In the 50% compressed state, the surface magnetic flux density was larger in Experimental Example 4. This is because, when compressed, the distribution density of the neodymium magnetic powder increases, and the direction of the magnetic moment of the neodymium magnetic powder becomes more aligned compared to the natural length state, so that both the number n of the neodymium magnetic powder per unit volume and the average value mz of the magnetic moment in the above relational formula (B) become larger, the magnetization Mz becomes larger, and the rate of change is also larger compared to the natural length state. It is believed that the increase in magnetization Mz results in an increase in magnetic flux density Bz (see relational formula (A)). In addition, in experimental example 3, even when compressed by 50%, the rate of change in surface magnetic flux density relative to the natural length state is 5.8%, whereas in experimental example 4, the rate of change relative to the natural length state is 7.6% with 10% compression, making it possible to increase the change in surface magnetic flux density (magnetic flux density) even with a small degree of elastic deformation.

Comparing the amount of electricity generated in Experimental Example 1 and Experimental Example 3, it can be seen that the amount of electricity generated is greater when the mass ratio (volume ratio) of the neodymium magnetic powder is greater. It can also be seen that the amount of electricity generated is greater when the compression rate (amount of displacement) is greater and the frequency is increased.

[Other embodiments]
(1) As a device for detecting the behavior of a component by utilizing the change in magnetic flux density accompanying the elastic deformation of the magnetic elastic body 20, a configuration in which a magnetic sensor such as a Hall element, a TMR element (tunnel magnetoresistance element), a GMR element (giant magnetoresistance element), an AMR element (anisotropic magnetoresistance element), or the like is arranged opposite the magnetic elastic body 20 can be considered.

(2) All of the electrical devices 100A to 100I described above are designed to operate on power generated by the power generation unit 10, but the power generation unit 10 may not be used as a power generation unit, and power may be provided by a battery or an external power source (e.g., a commercial power source). The power generation unit 10 may be used only as a detection unit that detects external forces, deformation of components, etc., and may not be provided with a load unit.

(3) Just as the electrical device 100I of the ninth embodiment can be used for twisting, bending, and expanding/contracting deformation, all of the electrical devices 100A to 100I described above may be used in other ways. In addition, the electrical load included in the load section of the electrical devices 100A to 100I may be changed as appropriate.

(4) In the first embodiment, the magnetic elastic body 20 is disposed inside the electromagnetic induction coil 12, but as long as the magnetic field generated by the magnetic powder 22 of the magnetic elastic body 20 penetrates the inside of the electromagnetic induction coil 12, the magnetic elastic body 20 may be disposed outside the electromagnetic induction coil 12.

(5) In the above embodiment, the magnetization direction of the magnetic elastic body 20 was the same as the axial direction of the electromagnetic induction coil 12, but it may be inclined with respect to the axial direction of the electromagnetic induction coil 12.

(6) In the above embodiment, the magnetic elastic body 20 is cylindrical, but this is not limited thereto, and it may be rectangular or spherical. It may also be in the shape of a product such as the bound stopper described above (see FIG. 11(B)).

(7) In the above embodiment, the electromagnetic induction coil 12 and the magnetic elastic body 20 are arranged coaxially, but the central axes of the electromagnetic induction coil 12 and the magnetic elastic body 20 may be arranged parallel to each other with a deviation from each other, or may be inclined from each other.

(8) The magnetic elastic body 20 has a structure in which magnetic powder 22 is dispersed in foamed elastomer 21, so it can be easily cut into any shape, and the cut body also becomes a magnet with a north pole and a south pole, so the magnetic elastic body 20 can be used as a toy. In addition, since the magnetic elastic body 20 is lighter than ferrite magnets, etc., it can also be used to levitate using the magnetic force of other magnets, etc.

(9) In the above embodiment, 1,5-naphthalene diisocyanate (NDI) was used as the raw isocyanate for the magnetic elastic body 20, but diphenylmethane diisocyanate (MDI) may also be used.

<Additional Notes>
The following describes the features of the inventions extracted from the above-mentioned embodiments, while indicating, as necessary, their effects, etc. In the following, for ease of understanding, the corresponding configurations in the above-mentioned embodiments are appropriately indicated in parentheses, but the present invention is not limited to the specific configurations indicated in parentheses.

[Feature A1]
an elastic body that contains magnetized magnetic powder, generates a magnetic field that penetrates the electromagnetic induction coil, and changes the magnetic flux density of the magnetic field when it elastically deforms due to an external force; a rectifier that rectifies an induced current induced in the electromagnetic induction coil due to the change in magnetic flux density; and a load unit that receives power from the rectifier and operates.

The electrical device of feature A1 has an elastic body that contains magnetized magnetic powder and generates a magnetic field that penetrates an electromagnetic induction coil. When such an elastic body is subjected to an external force and elastically deforms, the magnetic flux density of the magnetic field that penetrates the electromagnetic induction coil changes, and self-generation occurs through electromagnetic induction. The induced current flowing through the electromagnetic induction coil is then rectified and applied to the load section, driving the load section. In this way, the electrical device of feature A1 can generate self-power with an elastic body that has a simpler structure than the rotating machines of conventional electrical devices.

[Feature A2]
The electric device according to feature A1, wherein the load unit includes a wireless circuit that outputs a wireless signal in response to power received from the rectification unit.

Electrical devices with feature A2 are self-powered and equipped with wireless circuits, allowing greater freedom in where they can be installed.

[Feature A3]
The electrical device according to feature A2, wherein the wireless circuit outputs a wireless signal every time power is received from the rectification unit to notify that the elastic body has received an external force.

Electrical equipment with feature A3 can be installed in a location subject to external force, allowing the external force conditions to be monitored from a remote location.

[Feature A4]
An electrical device described in any one of features A1 to A3, wherein the load section includes a detection circuit that generates detection data for identifying the external force based on the induced current, and a wireless circuit that wirelessly transmits the detection data.

The electrical device of feature 4 generates detection data for identifying external forces based on induced currents and then transmits it wirelessly, making it possible to collect data at remote locations far from the electrical device that is less susceptible to noise caused by wireless transmission.

[Feature A5]
The electric device according to any one of Features A1 to A4, wherein the rectification unit includes a secondary battery that is charged by the induced current and can supply power to the load unit.

Feature 5: The inclusion of a secondary battery stabilizes the power supply to the load.

[Feature A6]
An electrical device according to any one of features A1 to A5, wherein the orientation of the magnetic moment of the magnetic powder changes with elastic deformation of the elastic body, thereby changing the magnetic flux density of the magnetic field penetrating the electromagnetic induction coil.

In order to change the magnetic flux density of the magnetic field, the distribution density of the magnetic powder that generates the magnetic field penetrating the electromagnetic induction coil may be changed by deforming the elastic body, or, as in feature 6, the orientation of the magnetic moment of the magnetic powder may be changed between being aligned with the axial direction of the electromagnetic induction coil and being not aligned.

[Feature A7]
The electrical device according to any one of Features A1 to A6, wherein the electromagnetic induction coil is wound to form a ring or a cylinder having a space inside to receive the elastic body, and the electrical device is provided with an expansion and contraction support mechanism that transmits the external force so as to expand and contract the elastic body in the winding axis direction of the electromagnetic induction coil.

Feature 7 allows for efficient power generation with a compact structure.

[Feature A8]
The electrical device according to any one of Features A1 to A6, further comprising a torsion support mechanism that transmits the external force so that the elastic body can be twisted around a winding axis of the electromagnetic induction coil.

Feature 8 is that it is possible to generate electricity by utilizing a rotating external force.

[Feature A9]
The electrical device according to any one of Features A1 to A8, wherein the elastic body is a foamed elastomer.

The elastic body of feature A9 is a foamed elastomer, so when it is compressed the air bubbles collapse and when it is stretched the air bubbles expand. This limits the change in size in the direction perpendicular to the direction of expansion and contraction that accompanies the expansion and contraction deformation, and reduces interference between the elastic body and the surrounding parts.

[Feature A10]
The electrical device according to Feature A9, wherein the foamed elastomer is a polyurethane elastomer, and the particle diameter of the magnetic powder is 3 to 200 μm.

In feature A10, the elastomer is a polyurethane elastomer, so the raw material of the elastomer can be hardened quickly. For example, if the elastomer is non-foamed silicone rubber, it takes a long time to harden the elastomer, and the magnetic powder settles while the elastomer is hardening, which tends to result in uneven dispersion of the magnetic powder within the elastomer. In contrast, in feature A10, the raw material of the elastomer can be hardened before the magnetic powder settles, and the magnetic powder can be uniformly dispersed within the elastomer. This makes it possible to easily disperse magnetic powder with a particle diameter of 100 μm or more, and to increase the magnetic flux density of the elastomer. In addition, from the standpoint of the moldability and ease of deformation of the elastomer, it is preferable that the particle diameter of the magnetic powder is 200 μm or less.

[Feature A11]
The electric device according to Feature A9 or Feature A10, wherein the foamed elastomer has an expansion ratio of 1.4 to 6 times and has at least a portion with an open cell structure.

In feature A11, the foamed elastomer has an expansion ratio of 1.4 to 6 times and has at least an open cell structure, making it easy to mold the elastic body and to elastically deform it, and making it easy to change the magnetic flux density of the elastic body. As a result, it becomes possible to make it easier to generate induced current in the circuit. In addition, because the foamed elastomer has at least a portion with an open cell structure, it is possible to prevent the foamed elastomer from shrinking after molding. Note that the above expansion ratio indicates the expansion ratio of the foamed elastomer alone, not the expansion ratio of the elastic body.

[Feature A12]
The electrical device according to any one of Features A9 to A11, wherein the magnetic powder is made of a hard ferromagnetic material, the mass concentration of the magnetic powder relative to the foamed elastomer is 40 to 80%, and the volume concentration of the magnetic powder relative to the foamed elastomer is 1.0 to 3.5%.

Feature A12 makes it easier to elastically deform the elastic body while also making it possible to increase the change in magnetic flux density of the elastic body.

[Feature A13]
The electrical device according to any one of Features A1 to A12, wherein the elastic body has a compression set of 30% or less in accordance with JIS K 6262:2013 Method A.

[Feature A14]
The electrical device according to any one of Features A1 to A13, wherein the elastic body has a repeated compressive strain of 20% or less when compressed by 50% 100,000 times at 1 Hz.

Features A13 and A14 allow the foamed elastomer to recover well after being elastically deformed. This reduces the settling of the foamed elastomer, making the elastomer more suitable for repeated use, even when the elastomer is used in applications where it is repeatedly compressed.

[Feature A15]
A manufacturing method for an electrical device described in any one of Features A1 to A14, comprising dispersing the magnetic powder within the elastic body, and magnetizing the magnetic powder in the compression direction of the elastic body while the elastic body is elastically deformed.

The manufacturing method of feature A15 makes it easy to manufacture an elastic body that exhibits a large change in magnetic flux density when compressed.

Note that although the present specification and drawings disclose specific examples of the technology included in the scope of the claims, the technology described in the claims is not limited to these specific examples, but includes various modifications and variations of the specific examples, as well as parts of the specific examples taken separately.

10 Power generating unit 12, 12V Electromagnetic induction coil 20, 20V, 20W Magnetic elastic body (elastic body)
21 foam elastomer 22 magnetic powder 35 adjustment mechanism 91, 91V, 91W rectification section 91A secondary battery 92.92V load section 100A to 100I electrical equipment

Claims (8)

1. An electromagnetic induction coil;
   an elastic body that contains magnetized magnetic powder, generates a magnetic field that penetrates the electromagnetic induction coil, and changes the magnetic flux density of the magnetic field when it is elastically deformed by an external force;
   a rectifier that rectifies an induction current induced in the electromagnetic induction coil due to a change in the magnetic flux density;
   A load unit that receives power from the rectification unit and operates accordingly;
   An electrical device comprising:
2. The electrical device according to claim 1, wherein the load section includes a wireless circuit that outputs a wireless signal in response to power received from the rectifier section.
3. The electrical device according to claim 2, wherein the wireless circuit outputs a wireless signal each time it receives power from the rectifier to notify that the elastic body has received an external force.
4. The load section includes:
   a detection circuit that generates detection data for identifying the external force based on the induced current;
   a wireless circuit for wirelessly transmitting the detection data;
   4. The electrical device according to claim 1 , further comprising:
5. The electrical device according to any one of claims 1 to 4, wherein the rectifier includes a secondary battery that is charged by the induced current and can supply power to the load.
6. The electrical device according to any one of claims 1 to 5, wherein the orientation of the magnetic moment of the magnetic powder changes with the elastic deformation of the elastic body, thereby changing the magnetic flux density of the magnetic field penetrating the electromagnetic induction coil.
7. The electromagnetic induction coil is wound so as to form an annular or cylindrical shape having a space therein for receiving the elastic body,
   7. The electric device according to claim 1, further comprising an expansion/contraction support mechanism that transmits the external force so as to expand and contract the elastic body in a winding axis direction of the electromagnetic induction coil.
8. The electrical device according to any one of claims 1 to 6, further comprising a torsion support mechanism that transmits the external force so that the elastic body can be twisted around the winding axis of the electromagnetic induction coil.

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