Power generation device and on-vehicle device

Abstract

This power generation device comprises magnets and a magnetic component that move relative to each other along a first direction. The magnetic component includes: a magnetic wire extending along the first direction; first magnetic pieces connected to the respective ends of the magnetic wire; second magnetic pieces extending from the respective first magnetic pieces along a second direction intersecting the first direction; and a coil disposed on the outer periphery of the magnetic wire. The magnets are disposed at positions that overlap the second magnetic pieces and do not overlap the coil. The N poles and the S poles of the magnets are disposed in parallel in the first direction. One of the second magnetic pieces and an N pole face each other, and the other of the second magnetic pieces and an S pole face each other.

Description

Power generating device and on-vehicle device

[0001] The present disclosure relates to a power generating device and an on-vehicle device. The present application claims priority based on Japanese Patent Application No. 2025-055673 filed on March 28, 2025. All the contents described in the aforementioned Japanese application are incorporated herein by reference.

[0002] The power generation module disclosed in Patent Document 1 includes a power generation element section, an induction yoke section, a magnet section, and a housing section. The power generation element section includes an elongated magnetic core and a coil wound around the magnetic core. The induction yoke section includes a first induction yoke connected to one end of the magnetic core and a second induction yoke connected to the other end of the magnetic core. The magnet section includes a first magnet and a second magnet that are relatively displaceable relative to the power generation element section in a direction perpendicular to the longitudinal direction of the magnetic core. The first magnet and the second magnet are arranged in parallel in the aforementioned perpendicular direction. The housing section holds the magnet section.

[0003] International Publication No. WO 2022 / 244088

[0004] The power generating device of the present disclosure includes a magnetic component and a magnet that relatively move along a first direction. The magnetic component includes a magnetic wire extending along the first direction, first magnetic pieces connected to each of both ends of the magnetic wire, second magnetic pieces each extending from the first magnetic piece along a second direction intersecting the first direction, and a coil arranged on an outer periphery of the magnetic wire. The magnet is arranged at a position overlapping the second magnetic piece without overlapping the coil. The N pole and S pole of the magnet are arranged in parallel in the first direction. One of the second magnetic pieces and the N pole face each other, and the other of the second magnetic pieces and the S pole face each other.

[0005] Figure 1 is a schematic perspective view showing the in-vehicle device of Embodiment 1. Figure 2 is a schematic top view showing the power generation device provided in the in-vehicle device of Embodiment 1. Figure 3 is a schematic front view showing the in-vehicle device of Embodiment 1 as viewed along the first direction D1. Figure 4 is a cross-sectional view taken along line IV-IV of Figure 1. Figure 5 is an enlarged view showing a first example of the relationship between the second magnetic piece and the magnet in Figure 4. Figure 6 is an enlarged view showing a second example of the relationship between the second magnetic piece and the magnet in Figure 4. Figure 7 is an enlarged view showing a third example of the relationship between the second magnetic piece and the magnet in Figure 4. Figure 8 is an enlarged view showing a fourth example of the relationship between the second magnetic piece and the magnet in Figure 4. Figure 9 is a schematic front view showing the in-vehicle device of Modification 1 as viewed along the first direction D1. Figure 10 is a schematic cross-sectional view showing the in-vehicle device of Modification 2. Figure 11 is a schematic perspective view showing the in-vehicle device of Embodiment 2. Figure 12 is a cross-sectional view taken along line XII-XII of Figure 11. Figure 13 is a schematic perspective view showing the in-vehicle device of Embodiment 3. Figure 14 is a schematic perspective view showing the power generation device provided in the vehicle-mounted device of Embodiment 3.

[0006] In Patent Document 1, the magnet passes through a point where it overlaps with the coil. Therefore, the length in the direction where the magnet and coil overlap tends to be long. Consequently, the power generation module tends to be large.

[0007] One of the purposes of this disclosure is to provide a power generation device that is easy to miniaturize.

[0008] The power generation device described herein is easy to miniaturize.

[0009] First, the embodiments of this disclosure will be listed and described.

[0010] (1) A power generation device according to one aspect of the present disclosure comprises a magnetic component and a magnet that move relative to each other along a first direction. The magnetic component includes a magnetic wire extending along the first direction, first magnetic pieces connected to each of the ends of the magnetic wire, second magnetic pieces extending from each of the first magnetic pieces along a second direction intersecting the first direction, and a coil disposed on the outer circumference of the magnetic wire. The magnet is positioned so as to overlap with the second magnetic pieces but not with the coil. The north pole and south pole of the magnet are arranged in parallel along the first direction. One of the second magnetic pieces and its north pole face each other, and the other of the second magnetic pieces and its south pole face each other.

[0011] In the power generation device described in (1) above, the relative movement changes the magnetic pole facing the second magnetic piece. If the magnetic pole facing the second magnetic piece is an N pole before movement, it alternates between S pole and N pole; if it is an S pole before movement, it alternates between N pole and S pole. This change in the magnetic pole facing each second magnetic piece causes magnetization reversal within the magnetic line. This electromagnetic induction associated with magnetization reversal generates a pulse voltage in the coil. Therefore, the power generation device described in (1) above can generate electricity using this pulse voltage. In other words, the power generation device described in (1) above can generate electricity without power. In the power generation device described in (1) above, the magnet is positioned so as to overlap with both second magnetic pieces without overlapping with the coil, and the relative movement does not pass through the area where it overlaps with the coil. Therefore, the power generation device described in (1) above can easily have its length in the direction perpendicular to both the first and second directions shortened. Thus, the power generation device described in (1) above can be made compact.

[0012] (2) In the power generation device described in (1) above, the magnetic wire may be a magnetic wire that generates the Great Barkhausen effect.

[0013] The magnetic wire described above undergoes a rapid magnetization reversal when a constant external magnetic field is applied, regardless of the rate of change of the external magnetic field. In other words, the power generation device described in (2) above is easy to generate electricity because it does not depend on the relative movement speed of the magnetic component and the magnet along the first direction.

[0014] (3) In the power generation device described in (1) or (2) above, the distance between each of the second magnetic pieces and the magnet may be 0 mm or more and 10 mm or less.

[0015] The power generation device described in (3) above has a distance of 10 mm or less, which makes it easier to reduce leakage magnetic flux and allow magnetic flux to pass through. The power generation device described in (3) above has a distance of 0 mm or more, which makes it easier to move the magnetic component and the magnet relative to each other along the first direction.

[0016] (4) In any of the power generation devices described in (1) to (3) above, the surface of each of the second magnetic pieces facing the magnet may have a corner portion with a radius of curvature of 0.1 mm or more and 1.0 mm or less.

[0017] The power generation device described in (4) above makes it easy to reduce the contact area between each second magnetic piece, which has an angle with a radius of curvature that satisfies the above range, and the magnet. Therefore, the power generation device described in (4) above makes it easy to move the magnetic component and the magnet relatively along the first direction even when each second magnetic piece and the magnet are in contact. Thus, the power generation device described in (4) above makes it easy to reduce the distance between each second magnetic piece and the magnet, and ultimately make it easy to set it to 0 mm.

[0018] (5) Any of the power generation devices described in (1) to (4) above may have a coating layer that covers at least one of the surfaces of each of the second magnetic pieces that face the magnet, and the surfaces of the magnet that face the second magnetic piece. The coating layer is made of fluororesin.

[0019] Fluororesin has low frictional resistance. Therefore, the power generation device described in (5) above has a coating layer made of fluororesin, which makes it easy to move the magnetic components and the magnets relative to each other along the first direction, even when each second magnetic piece is in contact with the magnet. Therefore, the power generation device described in (5) above makes it easy to reduce the distance between each second magnetic piece and the magnet, and ultimately make it easy to set it to 0 mm.

[0020] (6) In any of the power generation devices described in (1) to (5) above, the shape of the magnet may be a sheet.

[0021] The power generation device described in (6) above is easy to make compact because the magnet is thin.

[0022] (7) An in-vehicle device according to one aspect of the present disclosure comprises a power generation device according to any of (1) to (6) above, and a transmitting device that transmits a signal to a receiving device using a first power generated by the relative movement of the magnetic component and the magnet along the first direction.

[0023] The in-vehicle device described in (7) above can operate the transmitter using the first power generated by the power generator.

[0024] (8) The in-vehicle device described in (7) above may include a circuit board to which the coil and the transmitter are electrically connected, and a case for which the circuit board is detachably housed. The magnet is fixed to the case.

[0025] In the in-vehicle device described in (8) above, when the circuit board is removed from the case, the transmitter operates using the first power generated by the generator. Therefore, the in-vehicle device described in (8) above can detect that the circuit board has been removed from the case.

[0026] (9) The in-vehicle device described in (7) above may include a circuit board to which the coil and the transmitter are electrically connected, and a case for housing the circuit board. The case has a bottom portion on which the circuit board is placed, and a lid portion that opens and closes in a direction perpendicular to the bottom portion. The lid portion has a ceiling portion facing the bottom portion, and a peripheral wall portion extending from the periphery of the ceiling portion toward the bottom portion. The magnet is fixed to the peripheral wall portion.

[0027] In the in-vehicle device described in (9) above, when the lid is opened, the transmitter operates using the first power generated by the generator. Therefore, the in-vehicle device described in (9) above can detect that the lid has been opened.

[0028] (10) The in-vehicle device described in (7) above may include a circuit board to which the coil and the transmitter are electrically connected, a case for housing the circuit board, a first connector fixed to the outer surface of the case, a second connector inserted into and removed from the first connector, a first member arranged from the first connector to the inside of the case, and a second member arranged on the second connector. The first member has a movable portion that can move back and forth. The second member presses the first member so as to move the movable portion back and forth in conjunction with the insertion and removal of the second connector from the first connector. The magnet is provided to move back and forth in conjunction with the movement of the movable portion.

[0029] In the in-vehicle device described in (10) above, when the second connector is unplugged from the first connector, the transmitter operates using the first power generated by the generator. Therefore, the in-vehicle device described in (10) above can detect that the second connector has been unplugged from the first connector.

[0030] (11) Any of the in-vehicle devices described in (7) to (10) above may further include a power storage device that stores a second power different from the first power. The transmitter is started using the second power.

[0031] The in-vehicle device described in (11) above is equipped with a power storage device, which allows the second power stored in the power storage device to be used to start the transmitter, thus enabling the transmitter to be reliably started even when the first power is low.

[0032] (12) The in-vehicle device described in (11) above may further include a generator that generates the second power by energy harvesting.

[0033] The above generator can generate electricity without any power supply. Therefore, the vehicle-mounted device (12) can store electricity in the energy storage device without any power supply.

[0034] (13) In the vehicle-mounted device described in (12) above, the generator may be a vibration generator.

[0035] Vibration generators are suitable for vehicle-mounted devices that are prone to vibration.

[0036] Embodiments of the power generation device and vehicle-mounted device of this disclosure will be described based on the drawings. In the drawings, some components may be exaggerated or simplified for the sake of clarity. The shapes, sizes, and positional relationships shown in each figure are represented for the purpose of clarifying the explanation and do not necessarily represent the actual shapes, sizes, and positional relationships. The same reference numerals in the figures indicate the same part or corresponding component.

[0037] [Embodiment 1] <In-vehicle device> The in-vehicle device 1 of Embodiment 1 will be described with reference to Figures 1 to 8. The in-vehicle device 1 of this example comprises a power generator 2 (Figures 1 and 2), a transmitter 3 (Figures 3 and 4), a circuit board 4 (Figures 3 and 4), and a case 5 (Figure 1). The power generator 2 generates electricity in response to changes in an external magnetic field. The transmitter 3 uses the power generated by the power generator 2 to transmit a signal to a receiving device (not shown). The circuit board 4 electrically connects the power generator 2 and the transmitter 3. The case 5 houses the power generator 2, the transmitter 3, and the circuit board 4. One of the features of the in-vehicle device 1 of this example is that it is equipped with a specific power generator 2. The in-vehicle device 1 of this example is used, for example, as a detection device to detect when the circuit board 4 has been removed from the case 5. The in-vehicle device 1 is not limited to the above detection device and can be used for other purposes. In the following description, the side of the circuit board 4 where the power generator 2 is located will be referred to as "up" and the opposite side as "down". However, these terms "up" and "down" are for explanatory purposes only and do not necessarily indicate the actual orientation of the vehicle-mounted device 1 when installed.

[0038] <<Power Generation Device>> As shown in Figures 1 and 2, the power generation device 2 comprises a magnetic component 21 and a magnet 27. The magnetic component 21 and the magnet 27 move relative to each other along a first direction D1. The first direction D1 is the direction along the axis of the coil 26 (Figure 2) provided on the magnetic component 21, which will be described later. In each figure, the direction opposite to the first direction D1, indicated by a single arrow, may also be called the first direction D1. This is also true for the second direction D2 and the third direction D3, which will be described later. The power generation device 2 generates electricity through this relative movement.

[0039] [Magnetic Components] The number of magnetic components 21 is not particularly limited. There may be one or more magnetic components 21. In this example, as shown in Figure 2, there are two magnetic components 21: a first magnetic component 21 and a second magnetic component 21. The configuration of both magnetic components 21 is the same. Each magnetic component 21 is electrically connected to the transmitter 3, which will be described later, by a circuit board 4 (Figures 3 and 4), which will be described later. As shown in Figures 3 and 4, each magnetic component 21 is arranged on the upper surface of the circuit board 4 with space between them. Each magnetic component 21 comprises one core 22 and one coil 26. In this example, each magnetic component 21 is arranged such that the axis of the coil 26 is parallel to the upper surface of the circuit board 4.

[0040] <Core> The core 22 allows the magnetic flux generated by the magnet 27 to pass through. The planar shape of the core 22 in this example is U-shaped, as shown in Figure 2. The core 22 has one or more magnetic wires 23, two first magnetic pieces 241, and two second magnetic pieces 242.

[0041] 《Magnetic Wires》 The magnetic wires 23 extend along the first direction D1. The number of magnetic wires 23 is not particularly limited and may be one or more. In this example, there are multiple magnetic wires 23. In this example, the multiple magnetic wires 23 are arranged longitudinally in a straight line without being twisted together. Any known magnetic wire 23 can be used for each magnetic wire 23. Each magnetic wire 23 may be a magnetic wire 23 that generates a large Barkhausen effect. A magnetic wire 23 that generates a large Barkhausen effect undergoes a rapid magnetization reversal when a constant external magnetic field is applied, independent of the rate of change of the external magnetic field. Therefore, the power generation device 2 is easier to generate electricity with because it does not depend on the relative speed of movement between the magnetic component 21 and the magnet 27 along the first direction D1, provided it is equipped with a magnetic wire 23 that generates a large Barkhausen effect. An example of a magnetic wire 23 that generates a large Barkhausen effect is a magnetic wire 23 such as the one disclosed in International Publication No. 2023 / 074693.

[0042] <First Magnetic Pieces> Each first magnetic piece 241 is connected to each end of the magnetic wire 23. The shape of each first magnetic piece 241 is not particularly limited. The shape of each first magnetic piece 241 may be, for example, a prismatic or cylindrical shape. In this example, the shape of each first magnetic piece 241 is a rectangular prismatic shape.

[0043] <Second Magnetic Piece> Each second magnetic piece 242 extends from each corresponding first magnetic piece 241 along the second direction D2. The second direction D2 is a direction intersecting the first direction D1. In the present example, the second direction D2 is a direction orthogonal to the first direction D1. In the present example, each second magnetic piece 242 is connected to the upper surface of the corresponding first magnetic piece 241. The shape of each second magnetic piece 242 is not particularly limited. In the present example, each second magnetic piece 242 has a rod shape. The cross-sectional shape of each second magnetic piece 242 is not particularly limited. The cross-sectional shape of each second magnetic piece 242 is, for example, an angular shape, a circular shape, or a semicircular shape. Corner portions of the angular shape may be rounded. In the present example, the cross-sectional shape of each second magnetic piece 242 is a square shape.

[0044] <Arrangement Form> The first magnetic component 21 and the second magnetic component 21 are arranged such that their respective magnetic wires 23 are parallel to each other. Both second magnetic pieces 242 of the first magnetic component 21 extend from each corresponding first magnetic piece 241 of the first magnetic component 21 toward the second magnetic component 21. Both second magnetic pieces 242 of the second magnetic component 21 extend from each corresponding first magnetic piece 241 of the second magnetic component 21 toward the first magnetic component 21. In the present example, along the first direction D1, one second magnetic piece 242 of the first magnetic component 21, one second magnetic piece 242 of the second magnetic component 21, the other second magnetic piece 242 of the first magnetic component 21, and the other second magnetic piece 242 of the second magnetic component 21 are arranged in order from the left to the right in FIG. 2.

[0045] <Coil> The coil 26 has a winding section arranged on the outer circumference of the magnetic wire 23. The winding section is cylindrical in shape. The winding section is constructed by winding a wire. The winding consists of a conductor wire and an insulating coating. The insulating coating covers the outer circumference of the conductor wire. The winding may further include a self-fusing layer provided as the outermost layer. The self-fusing layer adheres the windings together. The fusion of the windings by the self-fusing layer joins adjacent turns together, maintaining the cylindrical shape of the winding section. A pulse voltage is generated in the coil 26 by electromagnetic induction accompanying the reversal of magnetization within the magnetic wire 23. The reversal of magnetization within the magnetic wire 23 is caused by the relative movement of the magnetic component 21 and the magnet 27 along a first direction D1. Both ends of the windings constituting the coil 26 are electrically connected to the circuit board 4. An induced current flows through the coil 26 due to the pulse voltage generated in the coil 26. The current flowing through coil 26 flows to the oscillator 3 via circuit board 4.

[0046] [Magnet] The magnet 27 generates magnetic flux. There is one magnet 27. The magnet 27 is positioned so as to overlap with the second magnetic piece 242 without overlapping with the coil 26. That is, the magnet 27 is positioned between the coil 26 of the first magnetic component 21 and the coil 26 of the second magnetic component 21. The shape of the magnet 27 in this example is sheet-like. Because the sheet-like magnet 27 is thin, it is easy to miniaturize the power generation device 2 and the on-board device 1. The magnet 27 in this example is fixed to the ceiling portion 53 of the case 5, which will be described later. In this example, the magnet 27 is positioned above each of the second magnetic pieces 242. The north pole 271 and south pole 272 of the magnet 27 are arranged alternately along the first direction D1.

[0047] In the first magnetic component 21 at the top of Figure 2, the second magnetic piece 242 located on the left side of the paper faces the south pole 272 of the magnet 27, and the second magnetic piece 242 located on the right side of the paper faces the north pole 271 of the magnet 27. In the second magnetic component 21 at the bottom of Figure 2, the second magnetic piece 242 located on the left side of the paper faces the north pole 271 of the magnet 27, and the second magnetic piece 242 located on the right side of the paper faces the south pole 272 of the magnet 27.

[0048] The magnet 27 is a permanent magnet. The permanent magnet is, for example, a neodymium magnet, an alnico magnet, a ferrite magnet, or a samarium-cobalt magnet. A permanent magnet does not require current to flow therethrough unlike an electromagnet, and therefore does not need a power supply.

[0049] [Distance between the second magnetic piece and the magnet] As shown in FIG. 5, the distance L between each second magnetic piece 242 and the magnet 27 is, for example, 0 mm or more and 10 mm or less. When the distance L is 10 mm or less, leakage magnetic flux can be easily reduced, and magnetic flux can easily pass through each second magnetic piece 242. When the distance L is 0 (zero) mm or more, the magnetic component 21 and the magnet 27 can be easily moved relatively along the first direction D1. The distance L may be 0 mm or more and 5 mm or less, or 0 mm or more and 2 mm or less.

[0050] The distance L may be 0 mm, that is, each second magnetic piece 242 and the magnet 27 may be in contact, as shown in the example in Figure 6. When each second magnetic piece 242 and the magnet 27 are in contact, each second magnetic piece 242 may have a corner portion 242a on the surface facing the magnet 27 that is formed as an arc. In the example shown in Figure 7, the cross-sectional shape of each second magnetic piece 242 is pentagonal. The radius of curvature R of the corner portion 242a is, for example, 0.1 mm or more and 1.0 mm or less. Each second magnetic piece 242 whose radius of curvature R of the corner portion 242a satisfies the above range can easily reduce the contact area with the magnet 27 compared to the case in which each second magnetic piece 242 does not have a corner portion 242a, as shown in the example in Figure 6. Therefore, even when each second magnetic piece 242 and the magnet 27 are in contact, the magnetic component 21 and the magnet 27 can be moved relatively along the first direction D1. The radius of curvature R may be 0.1 mm or more and 0.7 mm or less, or 0.1 mm or more and 0.4 mm or less. When each second magnetic piece 242 and the magnet 27 are in contact, the power generation device 2 may have a coating layer 25 that covers at least one of the surfaces of each second magnetic piece 242 facing the magnet 27 and the surface of the magnet 27 facing the second magnetic piece 242, as shown in Figure 8. The coating layer 25 is made of, for example, fluororesin. Fluororesin has low frictional resistance. Therefore, by having a coating layer 25 made of fluororesin, it is easier to move the magnetic component 21 and the magnet 27 relatively along the first direction D1 even when each second magnetic piece 242 and the magnet 27 are in contact, compared to the case where there is no coating layer 25 as shown in the example in Figure 6.

[0051] ≪Transmitting Device≫ The transmitting device 3 shown in Figures 3 and 4 transmits a signal to a receiving device (not shown). The transmitting device 3 is activated using the power generated by the power generator 2 shown in Figure 2. When the transmitting device 3 transmits a signal, it means that the power generator 2 has generated power, that is, that the magnetic component 21 and the magnet 27 have moved relative to each other along the first direction D1. By transmitting a signal, it is possible to detect that the circuit board 4 has been removed from the case 5. For example, if the circuit board 4 is a component of an ECU (Electronic Control Unit), the transmitting device 3 can detect that the ECU has been illegally removed by transmitting a signal to the receiving device. In this example, the transmitting device 3 is located on the underside of the circuit board 4. Unlike this example, the transmitting device 3 may be located on the top side of the circuit board 4. The communication method of the transmitting device 3 may be either wireless communication or wired communication. If the communication method of the transmitting device 3 is wireless communication, a communication line is not required, unlike when the communication method of the transmitting device 3 is wired communication. If the communication method of the transmitting device 3 is wired communication, it is easier to transmit signals stably compared to when the communication method of the transmitting device 3 is wireless communication.

[0052] <Circuit Board> The circuit board 4 shown in Figures 3 and 4 constitutes a current circuit from the power generator 2 shown in Figure 2 to the oscillator 3 shown in Figures 3 and 4. The power generator 2 and the oscillator 3 are electrically connected to the circuit board 4. A rectifier (not shown) for rectifying the pulse voltage may be provided in the middle of the current circuit. That is, the current circuit may be designed so that the current generated by the power generator 2 flows in the order of circuit board 4, rectifier, and oscillator 3. The circuit board 4 in this example is inserted into and removed from the case 5.

[0053] ≪Case≫ Case 5 in this example houses a circuit board 4 so that it can be inserted into and removed from the inside and outside, as shown in Figure 1. Case 5 in this example has a bottom portion 51, a top portion 53, and a peripheral wall portion 54. The bottom portion 51 faces the lower surface of the circuit board 4. The top portion 53 faces the upper surface of the circuit board 4. The peripheral wall portion 54 connects the bottom portion 51 and the top portion 53. The peripheral wall portion 54 has an opening 541. The opening 541 opens in the direction opposite to the first direction D1. The circuit board 4 is inserted into and removed from the inside and outside of case 5 through this opening 541. Case 5 is made of, for example, a resin, which is a non-magnetic material.

[0054] When the circuit board 4 is pulled out of case 5, the magnetic component 21 and the magnet 27 move relative to each other along the first direction D1. This movement changes the magnetic pole facing the second magnetic piece 242. If the magnetic pole facing the second magnetic piece 242 was an N pole 271 before the movement, it alternates between an S pole 272 and an N pole 271. If it was an S pole 272 before the movement, it alternates between an N pole 271 and an S pole 272. This change in the magnetic pole facing each second magnetic piece 242 causes magnetization reversal within the magnetic line 23. This electromagnetic induction associated with magnetization reversal generates a pulse voltage in the coil 26. Therefore, the power generation device 2 can generate electricity with this pulse voltage. When the circuit board 4 is pulled out, the magnet 27 does not pass through the area where it overlaps with the coil 26. Therefore, it is easy to shorten the length of the third direction D3 of the power generation device 2. The third direction D3 is perpendicular to both the first direction D1 and the second direction D2. Therefore, the power generation device 2 can be made smaller. Since the length of the third direction D3 of the power generation device 2 can be easily shortened, the length of the third direction D3 of case 5, which will be described later, can also be easily shortened. Therefore, the on-board device 1 can be made smaller.

[0055] [Modification 1] <In-vehicle device> As shown in the in-vehicle device of Modification 1 in Figure 9, each second magnetic piece 242 may be connected to the lower surface of each first magnetic piece 241. Compared to the in-vehicle device 1 of Embodiment 1, the in-vehicle device of this example makes it easier to reduce the distance between the ceiling portion 53 of the case 5 and the magnetic component 21. Therefore, the in-vehicle device of this example makes it easier to shorten the length of the third direction D3, and thus easier to make compact.

[0056] [Modified Example 2] <In-vehicle device> As shown in the in-vehicle device of Modified Example 2 in Figure 10, the magnet 27 may be configured in an L-shape and suspended from the ceiling portion 53, and positioned between each second magnetic piece 242 and the circuit board 4. That is, the magnet 27 may be cantilevered to the ceiling portion 53. Compared to the in-vehicle device 1 of Embodiment 1, the in-vehicle device of this example makes it easier to reduce the distance between the ceiling portion 53 of the case 5 and the magnetic component 21. Therefore, the in-vehicle device of this example makes it easier to shorten the length of the third direction D3, and thus easier to make compact.

[0057] [Embodiment 2] <In-vehicle device> The in-vehicle device 1 of Embodiment 2 will be described with reference to Figures 11 and 12. The in-vehicle device 1 of this example differs from the in-vehicle device 1 of Embodiment 1 in that the power generator 2 generates electricity by opening and closing the case 5. The following description will focus on the differences from Embodiment 1. Descriptions of the same or similar configurations as in Embodiment 1 may be omitted. These points are also the same in Embodiment 3, which will be described later.

[0058] ≪Power Generation Device≫ The configuration and number of magnetic components 21 in this example are the same as those of the power generation device 2 in Embodiment 1. The two magnetic components 21 in this example are arranged on the upper surface of the circuit board 4 such that the axis of the coil 26 is perpendicular to the upper surface of the circuit board 4. The two magnetic components 21 are arranged so as to sandwich the magnet 27. That is, each magnetic component 21 is arranged so that the coil 26 and the magnet 27 do not overlap. The magnet 27 in this example is fixed to the peripheral wall portion 54, which will be described later. The north pole 271 and south pole 272 of the magnet 27 are arranged alternately along the first direction D1. That is, the north pole 271 and south pole 272 of the magnet 27 are arranged alternately along the direction perpendicular to the upper surface of the circuit board 4.

[0059] ≪Case≫ Case 5 in this example has a bottom portion 51 and a lid portion 52. A circuit board 4 is placed on the bottom portion 51. The bottom portion 51 is flat. The lid portion 52 opens and closes in a direction perpendicular to the bottom portion 51. The lid portion 52 has a top portion 53 and a peripheral wall portion 54. The top portion 53 faces the bottom portion 51. The peripheral wall portion 54 extends from the periphery of the top portion 53 toward the bottom portion 51.

[0060] When the lid 52 is opened, that is, when the lid 52 is lifted so that it separates from the bottom 51 in a direction perpendicular to it, the magnetic component 21 and the magnet 27 move relative to each other along the first direction D1. This movement changes the magnetic pole facing the second magnetic piece 242. If the magnetic pole facing the second magnetic piece 242 was an N pole 271 before the movement, it alternates between an S pole 272 and an N pole 271. If it was an S pole 272 before the movement, it alternates between an N pole 271 and an S pole 272. Therefore, the power generation device 2 in this example can generate electricity. When the lid 52 is opened, the magnet 27 does not pass through the area where it overlaps with the coil 26. Therefore, it is easy to shorten the length of the third direction D3 of the power generation device 2. Thus, the power generation device 2 can be made smaller. Because it is easy to shorten the length of the third direction D3 of the power generation device 2, it is easy to shorten the length of the third direction D3 of the case 5. Thus, it is easy to make the vehicle-mounted device 1 smaller.

[0061] [Embodiment 3] <In-vehicle device> The in-vehicle device 1 of Embodiment 3 will be described with reference to Figures 13 and 14. The in-vehicle device 1 of this embodiment differs from the in-vehicle device 1 of Embodiment 1 in that the power generation device 2 generates power by pulling out the second connector 62 from the first connector 61. The in-vehicle device 1 of this embodiment further comprises the first connector 61, the second connector 62, the first member 71, and the second member 72.

[0062] <Power Generation Device> The configuration of the magnetic component 21 in this example is the same as that of the power generation device 2 in Embodiment 1. In this example, each magnetic component 21 is arranged such that the axis of the coil 26 is parallel to the upper surface of the circuit board 4. The axis of the coil 26 is parallel to the direction along the length of the reciprocating portion 711 of the first member 71, which will be described later. The magnet 27 in this example is fixed to the upper surface of the plate member 91, which will be described later.

[0063] <<First Connector and Second Connector>> The first connector 61 is fixed to the outer surface of the case 5. The first connector 61 is electrically connected to the circuit board 4. The second connector 62 is inserted into and removed from the first connector 61. When the second connector 62 is inserted into the first connector 61, it is electrically connected to the first connector 61. In this example, the first connector 61 is fixed to the outer surface of the case 5 such that the insertion and removal direction of the second connector 62 to the first connector 61 is along the first direction D1.

[0064] ≪First Member and Second Member≫ The first member 71 is positioned from the first connector 61 to the inside of the case 5. The first member 71 has a movable movable portion 711. The movable portion 711 is biased by a biasing member (not shown) to move toward the first connector 61 along the first direction D1. In this example, the first member 71 is a contact probe. The second member 72 is positioned on the second connector 62. The second member 72 presses the first member 71 to move its movable portion 711 toward and toward in conjunction with the insertion and removal of the second connector 62 from the first connector 61. In this example, the second member 72 is a pin member. When the second connector 62 is connected to the first connector 61, the movable portion 711 of the first member 71 is pressed by the second member 72 against the biasing by the biasing member. That is, the movable portion 711 is pressed toward away from the first connector 61 along the first direction D1. When the second connector 62 is withdrawn from the first connector 61, the second member 72 does not press against the retractable portion 711 of the first member 71. Therefore, the retractable portion 711 of the first member 71 moves in the direction biased by the biasing member. That is, the retractable portion 711 is moved by the biasing member to approach the first connector 61 along the first direction D1.

[0065] The retractable portion 711 of the first member 71 in this example is connected to the plate member 91, as shown in Figure 14. That is, the plate member 91 slides in conjunction with the retraction of the retractable portion 711. In this example, the plate member 91 is slidably held by a slide guide 92. The slide guide 92 in this example is fixed to the upper surface of the circuit board 4. The plate member 91 in this example is positioned between the coil 26 of the first magnetic component 21 and the coil 26 of the second magnetic component 21, and between the upper surface of the circuit board 4 and each of the second magnetic pieces 242.

[0066] When the second connector 62 is withdrawn from the first connector 61, the pressure on the retractable portion 711 of the first member 71 by the second member 72 is released. Following this release, the retractable portion 711 moves towards the first connector 61 along the first direction D1 by the biasing member. As the retractable portion 711 moves towards the first connector 61, the plate member 91 connected to the retractable portion 711 also moves towards the first connector 61 along the first direction D1. Since the magnet 27 is fixed to the upper surface of the plate member 91, the above movement of the plate member 91 changes the magnetic pole facing the second magnetic piece 242. If the magnetic pole facing the second magnetic piece 242 was an N pole 271 before the movement, it alternates between an S pole 272 and an N pole 271, and if it was an S pole 272 before the movement, it alternates between an N pole 271 and an S pole 272. Therefore, the power generation device 2 of this example can generate electricity. When the second connector 62 is pulled out from the first connector 61, the magnet 27 does not pass over the coil 26. Therefore, the length of the third direction D3 of the power generation device 2 can be shortened. Thus, the power generation device 2 can generate power despite its small size. Because the length of the third direction D3 of the power generation device 2 can be shortened, the length of the third direction D3 of the case 5 can also be shortened. Thus, the on-board device 1 can be made smaller.

[0067] <Other> The in-vehicle device 1 in this example may further include a power storage device 81 and a generator 82, as shown in Figure 14.

[0068] The energy storage device 81 stores a second power, which is different from the first power generated by the power generation device 2. The second power is power generated by the generator 82. The on-board device 1 uses the first power and the second power to start the transmitter 3. By providing the energy storage device 81, the second power stored in the energy storage device 81 can be used to start the transmitter 3, so the transmitter 3 can be reliably started even if the first power is low. The energy storage device 81 is electrically connected to the circuit board 4.

[0069] The generator 82 is a generator that generates second power by energy harvesting. That is, the generator 82 can generate power without any power supply. Therefore, the on-board device 1 in this example can store power in the energy storage device 81 without any power supply. The generator 82 is, for example, a vibration generator. Since the on-board device 1 is prone to vibration, the fact that the generator 82 is a vibration generator allows it to efficiently generate power by utilizing the vibrations during vehicle operation. The generator 82 is electrically connected to the circuit board 4. The second power generated by the generator 82 is sent to the energy storage device 81 via the circuit board 4.

[0070] The present invention is not limited to the configurations shown in the embodiments, but is intended to include all modifications within the meaning and scope of the claims as indicated by the claims. It should be understood that at least one configuration or feature described in each embodiment can be combined with other embodiments or modified in various ways.

[0071] For example, the in-vehicle devices of Embodiments 1 and 2 and Modifications 1 and 2 described above may further include the energy storage device 81 and the generator 82 described in Embodiment 3.

[0072] 1. On-board device 2. Power generation device 21. Magnetic component, 22. Core, 23. Magnetic wire 241. First magnetic piece, 242. Second magnetic piece, 242a. Corner 25. Coating layer, 26. Coil 27. Magnet, 271. North pole, 272. South pole 3. Transmitter 4. Circuit board 5. Case 51. Bottom, 52. Lid, 53. Top, 54. Peripheral wall, 541. Opening 61. First connector, 62. Second connector 71. First member, 711. Moving part, 72. Second member 81. Energy storage device, 82. Generator 91. Plate member, 92. Slide guide D1. First direction, D2. Second direction, D3. Third direction L. Distance, R. Radius of curvature

Claims

1. A power generation device comprising a magnetic component and a magnet that move relative to each other along a first direction, wherein the magnetic component has a magnetic wire extending along the first direction, a first magnetic piece connected to each of the ends of the magnetic wire, a second magnetic piece extending from each of the first magnetic pieces along a second direction intersecting the first direction, and a coil disposed on the outer circumference of the magnetic wire, the magnet being positioned so as to overlap with the second magnetic piece without overlapping with the coil, the north pole and south pole of the magnet being arranged in parallel along the first direction, with one of the second magnetic pieces and its north pole facing each other, and the other of the second magnetic piece and its south pole facing each other.

2. The power generation apparatus according to claim 1, wherein the magnetic wire is a magnetic wire that generates the Great Barkhausen effect.

3. The power generation device according to claim 1 or claim 2, wherein the distance between each of the second magnetic pieces and the magnet is 0 mm or more and 10 mm or less.

4. The power generation device according to any one of claims 1 to 3, wherein each of the second magnetic pieces has a corner portion with a radius of curvature of 0.1 mm or more and 1.0 mm or less on the surface facing the magnet.

5. The power generation device according to any one of claims 1 to 4, wherein each of the second magnetic pieces has a coating layer covering at least one of the surfaces facing the magnet and the surfaces of the magnet facing the second magnetic piece, the coating layer being made of fluororesin.

6. The power generation device according to any one of claims 1 to 5, wherein the shape of the magnet is sheet-like.

7. An in-vehicle device comprising: a power generation device according to any one of claims 1 to 6; and a transmitting device that transmits a signal to a receiving device using first power generated by the relative movement of the magnetic component and the magnet along the first direction.

8. The in-vehicle device according to claim 7, comprising a circuit board to which the coil and the oscillator are electrically connected, and a case for removably housing the circuit board, wherein the magnet is fixed to the case.

9. The vehicle-mounted device according to claim 7, comprising: a circuit board to which the coil and the oscillator are electrically connected; and a case for housing the circuit board, wherein the case has a bottom portion on which the circuit board is placed; and a lid portion that opens and closes in a direction perpendicular to the bottom portion; the lid portion has a top portion facing the bottom portion; and a peripheral wall portion extending from the periphery of the top portion toward the bottom portion; and the magnet is fixed to the peripheral wall portion.

10. The in-vehicle device according to claim 7, comprising: a circuit board to which the coil and the transmitter are electrically connected; a case for housing the circuit board; a first connector fixed to the outer surface of the case; a second connector inserted into and removed from the first connector; a first member arranged from the first connector to the inside of the case; and a second member arranged on the second connector, wherein the first member has a retractable portion that can move back and forth; the second member presses the first member so as to move the retractable portion back and forth in conjunction with the insertion and removal of the second connector from the first connector; and the magnet is provided to move back and forth in conjunction with the movement of the retractable portion.

11. The in-vehicle device according to any one of claims 7 to 10, further comprising a power storage device for storing a second power different from the first power, wherein the transmitting device is activated using the second power.

12. The vehicle-mounted device according to claim 11, further comprising a generator that generates the second power by energy harvesting.

13. The vehicle-mounted device according to claim 12, wherein the generator is a vibration generator.

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