JP2013143897A - Power generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generator using reverse magnetostriction phenomenon and having a novel structure.SOLUTION: The power generator comprises: a magnetic field application member formed while including a magnet and having one end on one magnetic pole side and a second end on the other magnetic pole side; a first magnetostriction member disposed between the first and second ends so as to be fixed to the first end but not fixed to the second end; a second magnetostriction member disposed side by side with the first magnetostriction member between the first and second ends so as to be fixed to the first end but not fixed to the second end; a connection member connecting the first and second magnetostriction members and interlinking the vibration thereof; a first coil wound around the first magnetostriction member; and a second coil wound around the second magnetostriction member.

Description

  The present invention relates to a power generator.

  The magnetostriction phenomenon is a phenomenon in which a magnetic material is deformed by a magnetic field applied from the outside. Magnetization inside the magnetostrictive material is changed by deforming the magnetostrictive material exhibiting a magnetostriction phenomenon by applying an external force while applying an external magnetic field. This phenomenon is called reverse magnetostriction phenomenon or billari effect. A power generation device using an inverse magnetostriction phenomenon has been proposed (see, for example, Non-Patent Documents 1 and 2).

Shonan Metaltech Co., Ltd., “Introduction of SMT-developed inverse magnetostrictive vibration generator”, [online], [searched on November 8, 2011], Internet <URL: http: //www.shonan-metaltec. com / HPdata / info_gyakujiwai_hatudenki.pdf> Toshiyuki Ueno, “Micro-vibration power generation device using magnetostrictive material”, [online], August 6, 2010, Kanazawa University New Technology Briefing, [November 8, 2011 search], Internet <URL: http : //jstshingi.jp/abst/p/10/1022/kanazawa1.pdf>

  An object of the present invention is to provide a power generation device using a reverse magnetostriction phenomenon and having a novel structure.

  According to an aspect of the present invention, a magnetic field application member formed including a magnet and having a first end on one magnetic pole side and a second end on the other magnetic pole side, and the first end A first magnetostrictive member disposed between the first end and the second end, and fixed to the first end and not fixed to the second end; and the first end and the second end Between the first magnetostrictive member, the second magnetostrictive member fixed to the first end portion and not fixed to the second end portion, the first magnetostrictive member and the first magnetostrictive member. A connecting member that connects two magnetostrictive members and interlocks the vibration of the first magnetostrictive member and the vibration of the second magnetostrictive member, the first coil wound around the first magnetostrictive member, and the second magnetostrictive member. A power generation device having a second coil wound around the member is provided.

  By adopting a structure in which one end side of the magnetostrictive member is fixed to the magnetic field applying member, the strength of the magnetic field applied to the magnetostrictive member can be changed during vibration of the magnetostrictive member.

FIG. 1 is a schematic front view of a vibration power generator according to an embodiment. FIG. 2A is a schematic front view of the vibration power generator according to the embodiment, and FIGS. 2B and 2C show a schematic magnetic flux distribution of a magnetic field applied to the magnetostrictive member. 3A and 3B are schematic front views of the vibration power generator according to the first modification and the second modification of the embodiment, respectively. 4A and 4B are a schematic top view and a schematic front view of the vibration power generator according to the first design example, respectively. FIG. 5 is a schematic front view of the vibration power generator according to the second design example. FIG. 6 is a schematic front view of a vibration power generator according to a third modification of the embodiment. 7A and 7B are a schematic top view and a schematic front view, respectively, of a vibration power generator according to a comparative example.

  A vibration power generator according to an embodiment of the present invention will be described.

  1 and 2A are schematic front views of the vibration power generator according to the embodiment. FIG. 2A shows a state in which the magnetostrictive members 6 and 7 are distorted during vibration, and FIG. 1 shows a state in which the magnetostrictive members 6 and 7 are not distorted. A state that does not vibrate or is not distorted as shown in FIG. 1 is referred to as a reference state, and a distorted state as shown in FIG. 2A is referred to as a distorted state.

  With reference to FIG. 1, the structure of the vibration electric power generating apparatus by an Example is demonstrated. A magnetic field applying member 5 is formed including the permanent magnet 1, the yoke 2, the permanent magnet 3, and the yoke 4. The N pole of the permanent magnet 1 and the S pole of the permanent magnet 3 are arranged opposite to each other with a gap therebetween, and the N pole of the permanent magnet 3 and the S pole of the permanent magnet 1 are U-shaped (U-shaped) yokes. 4 is connected. The yoke 2 is connected to the S pole side of the permanent magnet 3.

  Magnetostrictive members 6 and 7 made of a magnetostrictive material are disposed between the permanent magnet 1 and the yoke 2, that is, between the N pole side end and the S pole side end of the magnetic field applying member 5. . As the magnetostrictive material, for example, an iron gallium alloy (Galfenol) can be used. The magnetostrictive members 6 and 7 have the same shape and are long and plate-shaped in one direction.

  The length direction of the magnetostrictive members 6 and 7 is preferably selected in the direction in which the magnetostrictive material is deformed (extends in this case) with respect to the external magnetic field. In FIG. 1, the vertical direction of the drawing is the thickness direction of the magnetostrictive members 6 and 7, and the horizontal direction of the drawing is the length direction of the magnetostrictive members 6 and 7.

  The magnetostrictive members 6 and 7 are arranged in parallel in the vertical direction, and one end of each is fixed to the permanent magnet 1. Further, the other ends of the magnetostrictive members 6 and 7 are not fixed to the yoke 2. The one end side end part and the other end side end part of the magnetostrictive members 6 and 7 fixed to the magnetic field applying member 5 are referred to as a root part and a tip part, respectively.

  The tip portions of the magnetostrictive members 6 and 7 are connected to each other by a connecting member 8, and a structure 9 in which the magnetostrictive members 6 and 7 are integrated is formed. The magnetostrictive members 6 and 7 (structure 9) have a cantilever structure in which the base side is a fixed end fixed to the magnetic field applying member 5 and the tip side is a movable end not fixed to the magnetic field applying member 5. A connecting member 8 is interposed between the yoke 2 and the magnetostrictive members 6 and 7, and a gap is disposed between the yoke 2 and the connecting member 8.

  The yoke 2 is divided into a portion 2 a that faces the upper magnetostrictive member 6 and a portion 2 b that faces the lower magnetostrictive member 7. In this embodiment, it is desirable that the upper surface height of the yoke 2a and the upper surface height of the upper magnetostrictive member 6 are aligned, and the lower surface height of the yoke 2b and the lower surface height of the lower magnetostrictive member 7 are aligned. It is desirable that the thickness of the yoke 2a (vertical width) is greater than the thickness of the upper magnetostrictive member 6, and that the thickness of the yoke 2b (vertical width) is greater than the thickness of the lower magnetostrictive member 7.

  The central position C2a in the vertical direction of the yoke 2a is arranged on the inner side (the vertical center or the magnetostrictive member 7 side) of the yoke 2a than the central position C6 in the vertical direction (thickness direction) of the magnetostrictive member 6. It is desirable. Further, the center position C2b in the vertical direction of the yoke 2b is arranged on the inner side (the vertical center side of the structure 9 or the magnetostrictive member 6 side) than the center position C7 in the vertical direction (thickness direction) of the magnetostrictive member 7. It is desirable that

  The permanent magnets 1 and 3 apply a magnetic field in the length direction of the magnetostrictive members 6 and 7. Along with the magnetostriction due to the application of the magnetic field, magnetic flux densities B6 and B7 are generated in the longitudinal direction of the magnetostrictive members 6 and 7, respectively. For example, Galfenol is a positive magnetostrictive material, and magnetostriction that extends in the direction of the applied magnetic field occurs when a magnetic field is applied. The applied magnetic field has a magnitude that does not saturate the magnetic flux density of the magnetostrictive members 6 and 7.

  Coils 10 and 11 are wound around the magnetostrictive members 6 and 7, respectively. In this embodiment, the coil 10 and the coil 11 are wound in opposite directions.

  In the vibration power generator according to the embodiment, the magnetic field applying member 5 is attached to the vibration source, and the magnetostrictive members 6 and 7 vibrate in the vertical direction due to the vibration of the vibration source.

  2A, 2B and 2C are also described, and the operation of the vibration power generator will be described. FIG. 2A illustrates a strain state in which the magnetostrictive members 6 and 7 are distorted as described above, and illustrates a case where the magnetostrictive members 6 and 7 are distorted downward. 2B and 2C show a schematic magnetic flux distribution of the magnetic field applied to the magnetostrictive member, FIG. 2B illustrates the case where the lower magnetostrictive member 7 is distorted downward, and FIG. 2C shows the lower magnetostrictive member. The case where 7 is distorted upward is illustrated.

  Since the tips of the magnetostrictive members 6 and 7 are connected to each other by the connecting member 8, the vibration of the magnetostrictive member 6 and the vibration of the magnetostrictive member 7 are interlocked. A neutral surface of the strain when the structure 9 in which the magnetostrictive members 6 and 7 are integrated vibrates in the vertical direction is disposed between the magnetostrictive member 6 and the magnetostrictive member 7.

  Therefore, when the structure 9 is distorted downward, tensile strain is generated in the upper magnetostrictive member 6 and compressive strain is generated in the lower magnetostrictive member 7. On the other hand, when the structure 9 is distorted upward, compressive strain is generated in the upper magnetostrictive member 6 and tensile strain is generated in the lower magnetostrictive member 7. The magnetostrictive members 6 and 7 repeatedly vibrate in a reference state without strain, a strain state in which compressive strain is generated, a reference state without strain, and a strain state in which tensile strain is generated. In the magnetostrictive member 6 and the magnetostrictive member 7, the direction of strain (whether it is compressive strain or tensile strain) is reversed.

  In general, when a magnetic field is applied from the outside, deformation of the magnetostrictive material changes the density of magnetic flux generated in the magnetostrictive material (inverse magnetostriction phenomenon or billiary effect). Here, the description will be made assuming that the applied magnetic field is constant. The magnetostrictive material is a positive magnetostrictive material such as, for example, Galfenol. In the reference state, the magnitude of the applied magnetic field is set so as not to saturate the magnetic flux density of the magnetostrictive member.

  When tensile strain occurs, that is, when the magnetostrictive member extends, the longitudinal component (magnetization component) of the magnetic flux density generated in the magnetostrictive member becomes larger than that in the reference state. On the other hand, when compressive strain occurs, that is, when the magnetostrictive member contracts, the longitudinal component (magnetization component) of the magnetic flux density generated in the magnetostrictive member is smaller than that in the reference state. Accordingly, the longitudinal component of the magnetic flux density generated in the magnetostrictive member periodically increases and decreases with vibration.

  In the vibration power generator according to the present embodiment, the strength of the magnetic field applied to the magnetostrictive member also changes with vibration. As shown in FIG. 2B, for example, when the lower magnetostrictive member 7 is distorted downward, the tip of the magnetostrictive member 7 moves so that the center C7 is away from the center C2b of the opposing yoke 2b. On the other hand, as shown in FIG. 2C, when the lower magnetostrictive member 7 is distorted upward, the tip of the magnetostrictive member 7 moves so that the center C7 approaches the center C2b of the opposing yoke 2b. In FIG. 2B and FIG. 2C, the connecting member 8 is omitted in order to avoid the complexity of illustration.

  In the portion of the yoke 2b facing the magnetostrictive material 7, the magnetic field strength of the applied magnetic field is higher (the magnetic line density is higher) in the vicinity of the center C2b than in the vicinity. Therefore, if the center C7 of the tip portion of the magnetostrictive member 7 moves away from the center C2b of the yoke 2b, the magnetic field applied to the magnetostrictive member 7 becomes weak and moves so as to approach the center C2b of the yoke 2b. The magnetic field applied to the magnetostrictive member 7 becomes stronger. Although the lower magnetostrictive member 7 has been described as an example, the same applies to the upper magnetostrictive member 6 in that the applied magnetic field increases and decreases with vibration.

  Therefore, when both the upper magnetostrictive member 6 and the lower magnetostrictive member 7 are distorted inward so as to generate tensile strain, the longitudinal component of the magnetic flux density is increased with the elongation of the magnetostrictive member (even if the applied magnetic field is constant). In addition, since the applied magnetic field itself becomes stronger, the longitudinal component of the magnetic flux density becomes larger. On the other hand, when the outer side is distorted so as to cause compressive strain, the longitudinal component of the magnetic flux density decreases with the contraction of the magnetostrictive member (even if the applied magnetic field is constant), and the applied magnetic field itself is weakened. The longitudinal component of the density becomes smaller.

  Inductive currents are generated in the coils 10 and 11 so as to prevent changes in magnetic flux density caused by the vibrations of the magnetostrictive members 6 and 7, respectively. Thereby, electric power generation can be performed. For example, in the state shown in FIG. 2A, in the coil 10 wound around the upper magnetostrictive member 6, a current flows from the tip side to the root side of the magnetostrictive member 6 so as to prevent an increase in magnetic flux density (the direction of the current is indicated by an arrow). ). That is, as a power source, the base side has a positive polarity and the tip side has a negative polarity.

  On the other hand, in the coil 11 wound around the lower magnetostrictive member 7, a current flows from the distal end side to the root side of the magnetostrictive member 7 so as to prevent the magnetic flux density from decreasing (the direction of the current is indicated by an arrow). That is, as a power source, the base side has a positive polarity and the tip side has a negative polarity.

  In the present embodiment, the coil 10 and the coil 11 are wound in opposite directions, so that the power source polarities on the distal end side and the root side can be made uniform on the magnetostrictive member 6 side and the magnetostrictive member 7 side. In addition, when the coil 10 and the coil 11 are wound in the same direction, the power source polarities are opposite on the magnetostrictive member 6 side and the magnetostrictive member 7 side, but power can be generated by the same mechanism.

  It should be noted that when the inward strain of each magnetostrictive member 6, 7 is maximized, the center positions of the magnetostrictive members 6, 7 are aligned with the center positions of the opposing yokes 2 a, 2 b, respectively. The positional relationship between the magnetostrictive member and the opposing yoke, which is considered preferable from the viewpoint of achieving the same, can be appropriately adjusted according to the vibration state of each power generation device.

  The connecting member 8 is preferably made of an insulating material, and more preferably made of a nonmagnetic material. For example, plastic or the like can be used as the insulating material and the nonmagnetic material. In addition, ferrite that is a magnetic material as an insulating material can also be used.

  When the conductivity of the connecting member 8 is high, an eddy current that reduces power generation efficiency is generated in the connecting member 8 along with the vibration of the magnetostrictive member. By reducing the conductivity of the connecting member 8, loss due to eddy current can be suppressed. The connecting member 8 is preferably formed of at least a material having a higher electrical resistivity than the coils 10 and 11.

  In this embodiment, the connecting member 8 is interposed between the yokes 2a and 2b and the magnetostrictive members 6 and 7. The connection member 8 is preferably a nonmagnetic material from the viewpoint of facilitating the design of the magnetic flux distribution between the yokes 2a and 2b and the magnetostrictive members 6 and 7.

  From the viewpoint of reducing the leakage magnetic flux, the thickness of the connecting member 8 is preferably thin as long as the strength can be secured, and the gap between the yokes 2a and 2b and the connecting member 8 is such that the connecting member 8 has the yoke. Narrower one is preferable as long as it does not interfere with 2a and 2b. It is also possible to cope with magnetic flux leakage by increasing the strength of the magnet as necessary.

  In this embodiment, as shown in FIG. 1, the connection member 8 connects the end surfaces of the magnetostrictive members 6 and 7, but the connection structure links the vibration of the magnetostrictive member 6 and the vibration of the magnetostrictive member 7. Is not limited to this. For example, a connection structure in which the magnetostrictive members 6 and 7 are connected at the base side is possible. However, the structure that connects the end-side end faces is preferable from the viewpoint of efficiently vibrating the magnetostrictive members 6 and 7.

  In addition, the shape of each magnetostrictive member 6 and 7 is not limited to plate shape, For example, it can also be set as rod shape. However, from the viewpoint of generating efficient vibration, it is preferable to have a shape having anisotropy that is likely to generate vibration in one direction as in the above embodiment. It is preferable that the upper and lower magnetostrictive members 6 and 7 are arranged side by side in a direction in which vibration is likely to occur with the same direction in which vibration is likely to occur.

  With reference to FIG. 3A, the vibration electric power generating apparatus by the 1st modification of the said Example is demonstrated. In the above embodiment, the yoke 2 is divided into the yokes 2a and 2b so as to face the magnetostrictive members 6 and 7, respectively. As a first modification, the yoke 2 can be structured not to be divided.

  Even in this case, as in the embodiment in which the yoke 2 is divided, when the magnetostrictive member 6 or 7 is distorted inward so as to generate tensile strain, the center of the tip portion moves so as to approach the center of the yoke 2. When the applied magnetic field can be relatively strengthened and the outer side is distorted so as to cause compressive strain, the center of the tip can be moved away from the yoke 2 to weaken the applied magnetic field.

  As in the above embodiment, dividing the yoke 2 so as to face the magnetostrictive members 6 and 7 is preferable from the viewpoint of applying a magnetic field by concentrating the magnetic lines of force on the magnetostrictive members 6 and 7.

  With reference to FIG. 3B, the vibration electric power generating apparatus by the 2nd modification of the said Example is demonstrated. In the above embodiment, in the reference state, the upper surface height of the upper magnetostrictive member 6 and the upper surface height of the opposing upper yoke 2a are aligned, the lower surface height of the lower magnetostrictive member 7, and the lower surface height of the opposing lower yoke 2b. Aligned.

  In the second modification, the upper surface height of the upper yoke 2a is made lower than the upper surface height of the upper magnetostrictive member 6, and the lower surface height of the lower yoke 2b is made higher than the lower surface height of the lower magnetostrictive member 7. Yes. Accordingly, it is considered that the applied magnetic field can be further weakened because the tip of the magnetostrictive member is further away from the yoke in a state in which the magnetostrictive member is distorted outward so that compressive strain is generated.

  Next, a more specific design example will be described.

  First, a first design example will be described with reference to FIGS. 4A and 4B. 4A and 4B are a schematic top view and a schematic front view of the vibration power generator according to the first design example, respectively. The structure of the reference state without distortion is shown. For the production of the power generation apparatus, machining techniques such as a machining center, a milling machine, a lathe, wire electric discharge machining, welding, and resin bonding can be appropriately used.

  The permanent magnet 21, the yoke 22, the yoke 23, the permanent magnet 24, and the yoke 25 form a magnetic field applying member. A permanent magnet 24 is disposed between the yoke 23 and the yoke 25, the permanent magnet 24 and the permanent magnet 21 are connected via the yoke 25, and the permanent magnet 21 is disposed between the yoke 25 and the yoke 22. . One magnetic pole side yoke 22 and the other magnetic pole side yoke 23 face each other.

  The permanent magnets 21 and 24 are 445 mT neodymium magnets, each having a thickness of 10 mm, a width of 15 mm, and a length of 15 mm, and are magnetized in the thickness direction. The yoke material is soft iron such as SS400.

Magnetostrictive members 26 and 27 are disposed between the yoke 22 and the yoke 23. The root portions of the magnetostrictive members 26 and 27 are fixed to the yoke 22. The magnetostrictive members 26 and 27 are each formed of Galfenol (Fe _81.4 Ga _18.6 ) and have a thickness of 5 mm, a width of 10 mm, and a length of 50 mm. The magnetostrictive members 26 and 27 are arranged in parallel, and the center-to-center distance is 15 mm.

  The tip portions of the magnetostrictive members 26 and 27 are connected by a connecting member 28. The connecting member 28 is made of bakelite. The yoke 23 has a convex portion 23 a that faces the upper magnetostrictive member 26 and a convex portion 23 b that faces the lower magnetostrictive material 27. The protruding heights of the convex portions 23a and 23b are 2 mm, and the gap between the convex portions 23a and 23b and the connection member 28 is about 1 mm to 3 mm.

  In the above embodiment, the yoke 2a facing the upper magnetostrictive member 6 and the yoke 2b facing the lower magnetostrictive member 7 are separated. In this design example, a yoke portion 23 a facing the upper magnetostrictive member 26 and a yoke portion 23 b facing the lower magnetostrictive material 27 are formed as a part of the integral yoke 23. Even in such a structure, it can be said that the yoke is divided so as to face each magnetostrictive member.

  The vertical widths (thicknesses) of the upper yoke portion 23a and the lower yoke portion 23b are each 7 mm. The center-to-center distance between the upper yoke portion 23a and the lower yoke portion 23b is 13 mm. The upper surface height of the upper yoke portion 23a and the upper surface height of the upper magnetostrictive member 26 are aligned, and the lower surface height of the lower yoke portion 23b and the lower surface height of the lower magnetostrictive member 27 are aligned.

  The vertical center of the upper yoke portion 23 a is arranged inside the vertical center of the upper magnetostrictive member 26, and the vertical center of the lower yoke portion 23 b is arranged inside the vertical center of the lower magnetostrictive member 27. Has been.

  Coils 29 and 30 are wound around the magnetostrictive members 26 and 27, respectively (the coils are shown in a simplified manner in order to avoid the complexity of illustration).

  A magnetic field applying member is connected to a clamp column 32 fixed to the support plate 31 via a clamp connection member 33 (material is, for example, aluminum or copper), and a side surface portion (permanent magnet 21, yoke 22, and yoke) on the magnetostrictive member base side. 25).

  Next, a second design example will be described with reference to FIG. FIG. 5 is a schematic front view of the vibration power generator according to the second design example. In the first design example, the one-side clamp structure in which the magnetic field application member is attached to the clamp column on the side surface on the base side of the magnetostrictive member. In the second design example, the magnetic field application member has a double-sided clamp structure in which the magnetostrictive member base side surface and the magnetostrictive member tip side surface are attached to the clamp pillar.

  A magnetic field applying member is attached to a clamp column 32 on one side fixed to the support plate 31 via a clamp connecting member 33 at a side portion (permanent magnet 21, yoke 22, and yoke 25) on the base side of the magnetostrictive member. ing. Furthermore, the magnetic field application member is connected to the clamp column 34 on the other side fixed to the support plate 31 via the clamp connection member 35 at the side surface portion (the yoke 23, the permanent magnet 24, and the yoke 25) on the tip side of the magnetostrictive member. It is attached.

  The vibration power generators of the first design example and the second design example can vibrate the magnetostrictive members 26 and 27 by vibration applied via the clamp pillar 32 and the like, and can generate power.

  These design examples are examples of trial manufacture, and the size and shape of the magnetostrictive member, the mounting structure, and the like can be changed as necessary. Although the vibration electric power generating apparatus by an Example may be used in what kind of mode, it can be used as follows, for example.

  Install the power generator of the example as a power source in a machine room machine with a lot of vibrations, and combine a sensor that detects abnormalities in temperature, gas, etc. with a radio that transmits information to the monitor room, to create a machine room abnormality detection system. Can be formed. Alternatively, the power generation apparatus of the embodiment can be attached to the bridge as a power source, and a bridge abnormality detection system can be formed by combining a strain sensor that measures fatigue and a radio that transmits information.

  In the above embodiment, the case where a positive magnetostrictive material is used for the magnetostrictive member is illustrated, but a negative magnetostrictive material can also be used for the magnetostrictive member as described below.

  With reference to FIG. 6, a vibration power generator according to a third modification using a negative magnetostrictive material for the magnetostrictive member will be described. In contrast to the positive magnetostrictive material described above, the negative magnetostrictive material causes the crystal to deform and contract in the direction opposite to the applied magnetic field direction when a magnetic field is applied. The magnetic flux density of the magnetostrictive members 6 and 7 increases when compressive strain is applied in a magnetic field applied state, and decreases when tensile strain is applied.

  In the power generator of the third modification, the yoke 2a facing the upper magnetostrictive member 6 has a center position C2a disposed above (outside) the center position C6 of the upper magnetostrictive member 6. The yoke 2b facing the lower magnetostrictive member 7 has a center position C2b disposed below (outside) the center position C7 of the lower magnetostrictive member 7.

  Thereby, for example, when the lower magnetostrictive member 7 is distorted outward (downward) so as to cause compressive strain, the magnetic flux density in the lower magnetostrictive member 7 increases due to the compressive strain, and the lower magnetostrictive member 7 The center position C7 approaches the center position C2b of the yoke 2b, and the applied magnetic field becomes stronger. On the other hand, when the lower magnetostrictive member 7 is distorted inward (upward) so that tensile strain is generated, the magnetic flux density in the lower magnetostrictive member 7 is reduced by the tensile strain, and the center position of the lower magnetostrictive member 7 is reduced. C7 moves away from the center position C2b of the yoke 2b, and the applied magnetic field becomes weak. The relationship between the upper magnetostrictive member 6 and the yoke 2a is the same.

  Thus, when a negative magnetostrictive material is used for the magnetostrictive member, the arrangement relationship between the center position of the divided yoke and the center position of the magnetostrictive member can be reversed from the case where the positive magnetostrictive material is used.

  Next, a vibration power generator according to a comparative example will be described. The vibration power generation apparatus according to the comparative example refers to the material “Micro-vibration power generation element using magnetostrictive material” (Non-patent Document 2) by Associate Professor Toshiyuki Ueno, Department of Electronic Information Science, Kanazawa University.

  7A and 7B are a schematic top view and a schematic front view, respectively, of a vibration power generator according to a comparative example. A magnetic field application member is formed including the permanent magnet 101, the yoke 102, the yoke 103, the permanent magnet 104, and the yoke 105. Magnetostrictive members 106 and 107 are arranged in parallel between the yoke 102 on one magnetic pole side of the magnetic field applying member and the yoke 103 on the other magnetic pole side. The magnetostrictive members 106 and 107 each have one end fixed to the yoke 102 and the other end fixed to the yoke 103. Coils 108 and 109 are wound around the magnetostrictive members 106 and 107, respectively.

  A magnetic field is applied to the magnetostrictive members 106 and 107 in the length direction, and a magnetic flux is generated along with the magnetostriction. When the magnetostrictive members 106 and 107 are distorted downward along with the vibration of the magnetostrictive members 106 and 107, tensile strain is generated in the upper magnetostrictive member 106 and magnetic flux is increased, and compressive strain is generated in the lower magnetostrictive member 107 and magnetic flux is reduced. . When the magnetostrictive members 106 and 107 are distorted upward, compressive strain is generated in the upper magnetostrictive member 106 and the magnetic flux is decreased, and tensile strain is generated in the lower magnetostrictive member 107 and the magnetic flux is increased. An induced current is generated in the coils 108 and 109 due to a change in magnetic flux accompanying the vibration, and power generation can be performed.

  In the power generator according to the comparative example, both ends of the magnetostrictive members 106 and 107 are fixed to the magnetic field applying member (on the yoke), and the magnetic field applied to the magnetostrictive members 106 and 107 is constant. On the other hand, in the power generator according to the embodiment, as described above, one end of the magnetostrictive members 6 and 7 is fixed to the magnetic field applying member, and the other end is not fixed to the magnetic field applying member (see FIG. 1). ).

  Due to such a structure, the power generator of the embodiment can increase the applied magnetic field when the magnetic flux increases due to the strain of the magnetostrictive member, and can decrease the applied magnetic field when the magnetic flux decreases due to the strain of the magnetostrictive member. This makes it easier to increase the width of the magnetic flux change than in the comparative example in which the applied magnetic field is constant, and the power generation efficiency can be improved.

  In the power generation apparatus according to the comparative example, the magnetostrictive member is supported by the magnetic field applying member at both ends (by the yoke), and the magnetostrictive member and the magnetic field applying member vibrate integrally (with the yoke). On the other hand, since the power generator according to the embodiment has a cantilever structure in which the other end of the magnetostrictive member is separated from the magnetic field applying member, the magnetostrictive member can be vibrated efficiently. Thereby, the power generation efficiency can be improved.

  As described above, the power generation efficiency can be improved by the vibration power generation device having the magnetostrictive member having one end fixed to the magnetic field application member.

  Although the present invention has been described with reference to the embodiments, the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications, improvements, combinations, and the like can be made.

The following additional notes are further disclosed with respect to the embodiment including the examples described above.
(Appendix 1)
A magnetic field applying member formed including a magnet and having a first end on one magnetic pole side and a second end on the other magnetic pole side;
A first magnetostrictive member disposed between the first end and the second end, fixed to the first end, and not fixed to the second end;
A second magnetostriction disposed between the first end and the second end along with the first magnetostrictive member, fixed to the first end, and not fixed to the second end. Members,
A connecting member that connects the first magnetostrictive member and the second magnetostrictive member and interlocks the vibration of the first magnetostrictive member and the vibration of the second magnetostrictive member;
A first coil wound around the first magnetostrictive member;
And a second coil wound around the second magnetostrictive member.
(Appendix 2)
The power generator according to appendix 1, wherein the connection member is formed of an insulating material.
(Appendix 3)
The power generator according to appendix 1 or 2, wherein the second end portion is divided into a first portion facing the first magnetostrictive member and a second portion facing the second magnetostrictive member.
(Appendix 4)
The first magnetostrictive member and the second magnetostrictive member are formed of a magnetostrictive material having a positive magnetostriction,
With respect to the direction in which the first magnetostrictive member and the second magnetostrictive member are arranged, the center of the first portion is arranged closer to the second magnetostrictive member than the center of the first magnetostrictive member, and the center of the second portion Is the power generation device according to appendix 3, which is disposed closer to the first magnetostrictive member than the center of the second magnetostrictive member.
(Appendix 5)
With respect to the direction in which the first magnetostrictive member and the second magnetostrictive member are arranged, the outer end of the first portion is disposed closer to the second magnetostrictive member than the outer end of the first magnetostrictive member. The power generating device according to appendix 4, wherein an outer end of the two portions is disposed closer to the first magnetostrictive member than an outer end of the second magnetostrictive member.
(Appendix 6)
The first magnetostrictive member and the second magnetostrictive member are made of a magnetostrictive material having negative magnetostriction,
With respect to the direction in which the first magnetostrictive member and the second magnetostrictive member are arranged, the center of the first portion is disposed on the opposite side of the second magnetostrictive member from the center of the first magnetostrictive member, and the second portion Is the power generation device according to appendix 3, wherein the center of the second magnetostrictive member is disposed on the opposite side of the first magnetostrictive member from the center of the second magnetostrictive member.
(Appendix 7)
The connection member according to any one of appendices 1 to 6, which connects an end on the second end side of the first magnetostrictive member and an end on the second end side of the second magnetostrictive member. Power generation device.
(Appendix 8)
The power generator according to any one of supplementary notes 1 to 7, wherein the connection member is formed of a nonmagnetic material.
(Appendix 9)
The power generation device according to any one of supplementary notes 1 to 8, wherein a direction in which the first coil is wound and a direction in which the second coil is wound are opposite.
(Appendix 10)
The shape of the first magnetostrictive member and the shape of the second magnetostrictive member are any one of appendices 1 to 9 having anisotropy that easily vibrates in a direction in which the first magnetostrictive member and the second magnetostrictive member are arranged. The power generator described in 1.

1, 3 Permanent magnets 2, 2a, 2b, 4 Yoke 5 Magnetic field applying members 6, 7 Magnetostrictive member 8 Connecting member 9 (Magnetostrictive members 6 and 7 are integrated) Structures 10, 11 Coils C2a, C2b, C6, C7 Center position 21, 24 Permanent magnet 22, 23, 23a, 23b, 25 Yoke 26, 27 Magnetostrictive member 28 Connection member 29, 30 Coil 31, Support plate 32, 34 Clamp post 33, 35 Clamp connection member

Claims (7)

A magnetic field applying member formed including a magnet and having a first end on one magnetic pole side and a second end on the other magnetic pole side;
A first magnetostrictive member disposed between the first end and the second end, fixed to the first end, and not fixed to the second end;
A second magnetostriction disposed between the first end and the second end along with the first magnetostrictive member, fixed to the first end, and not fixed to the second end. Members,
A connecting member that connects the first magnetostrictive member and the second magnetostrictive member and interlocks the vibration of the first magnetostrictive member and the vibration of the second magnetostrictive member;
A first coil wound around the first magnetostrictive member;
And a second coil wound around the second magnetostrictive member.   The power generation device according to claim 1, wherein the connection member is formed of an insulating material.   3. The power generation device according to claim 1, wherein the second end portion is divided into a first portion facing the first magnetostrictive member and a second portion facing the second magnetostrictive member. The first magnetostrictive member and the second magnetostrictive member are formed of a magnetostrictive material having a positive magnetostriction,
With respect to the direction in which the first magnetostrictive member and the second magnetostrictive member are arranged, the center of the first portion is arranged closer to the second magnetostrictive member than the center of the first magnetostrictive member, and the center of the second portion Is a power generation device according to claim 3, which is disposed closer to the first magnetostrictive member than the center of the second magnetostrictive member. The first magnetostrictive member and the second magnetostrictive member are made of a magnetostrictive material having negative magnetostriction,
With respect to the direction in which the first magnetostrictive member and the second magnetostrictive member are arranged, the center of the first portion is disposed on the opposite side of the second magnetostrictive member from the center of the first magnetostrictive member, and the second portion The power generation device according to claim 3, wherein a center of the second magnetostrictive member is disposed on a side opposite to the first magnetostrictive member from a center of the second magnetostrictive member.   6. The connection member according to claim 1, wherein the connection member connects an end on the second end side of the first magnetostrictive member and an end on the second end side of the second magnetostrictive member. Power generator.   The power generation device according to claim 1, wherein the connection member is made of a nonmagnetic material.

Images