JP2016077037A - Power generation device and power generation device design method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generation device capable of widening a frequency range in which power can be generated, while suppressing increase in the number of components.SOLUTION: To a first power generation element 11 which performs vibration power generation by utilizing reverse magnetostrictive effects of a magnetostrictive material, an eigen frequency is set which is between two target frequencies different from each other within a frequency range of vibrations to be detected in a vibrator 17 and different from a frequency indicating a maximum vibration acceleration. Thus, power can be generated even of vibrations in a frequency different from the eigen frequency of the first power generation element 11 are applied from the vibrator 17. The need of a separate component such as a dynamic damper can be eliminated, thereby widening the frequency range in which power can be generated, while suppressing increase in the number of components.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power generation apparatus that performs vibration power generation using the inverse magnetostriction effect of a magnetostrictive material and a method for designing the power generation apparatus, and more particularly to a power generation apparatus that can widen the range of frequencies that can be generated and a method for designing the power generation apparatus. .

  Conventionally, there is a power generation element that performs vibration power generation using the inverse magnetostriction effect of a magnetostrictive material. When the power generation element is given a resonance frequency, the vibration is amplified and power generation is performed. Patent Document 1 discloses a power generation device in which a power generation element in which at least one of two beam members forming a parallel beam is made of a magnetostrictive material is coupled to a vibrating body via a dynamic damper. . By coupling the power generating element to the vibrating body via the dynamic damper, vibrations with two or more degrees of freedom can be used, and the range of frequencies that can be generated can be widened.

JP 2014-118443 A

  However, the above-described conventional technique requires a dynamic damper, which increases the number of parts.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power generator and a power generator design method capable of widening the range of frequencies that can be generated while suppressing an increase in the number of components. .

Means for Solving the Problems and Effects of the Invention

  In order to achieve this object, the power generator according to claim 1 is configured such that the first rigid rod configured from the magnetic material in the shape of a rod is opposed to the first magnetostrictive rod configured from the magnetostrictive material in the shape of a rod. The A first coil is disposed on at least the first magnetostrictive rod of the first rigid rod and the first magnetostrictive rod, and one end side in the axial direction of the first magnetostrictive rod and the first rigid rod is supported by the first support member. The first support member is fixed to a vibrating body that outputs vibrations having a plurality of frequency components. The other ends in the axial direction of the first magnetostrictive rod and the first rigid rod are held by the first mass member. The first mass member extends or contracts the first magnetostrictive rod and the first rigid rod in the axial direction by relative movement with the first support member. The first power generating element configured in this way is set to a natural frequency that is between two different target frequencies within the frequency range of vibration output by the vibrating body and is different from the frequency exhibiting the largest vibration acceleration. Is done. Therefore, even when a vibration having a frequency different from the natural frequency is applied from the vibrating body to the first power generation element, the first power generation element can be vibrated to generate power. Therefore, the range of frequencies that can be generated can be widened. Since another component such as a dynamic damper can be made unnecessary, there is an effect that the frequency range in which power can be generated can be widened while suppressing an increase in the number of components.

  According to the power generation device of claim 2, the natural frequency is set based on one or more of the magnitude of two target frequencies, the magnitude of vibration acceleration at the two target frequencies, and the frequency of occurrence of multiple vibrations. Thus, in addition to the effect of the first aspect, the first power generating element can be easily designed.

  According to the power generation device of the third aspect, the natural frequency is set closer to the target frequency on the high frequency side of the two target frequencies. Since the generated voltage due to the vibration of the first power generation element is proportional to the natural frequency, in addition to the effect of claim 1 or 2, by setting the natural frequency closer to the target frequency on the high frequency side, it depends on the vibration acceleration. However, there is an effect that the generated voltage can be increased as compared with the case where the natural frequency is set closer to the target frequency on the low frequency side.

  According to the power generator of claim 4, the difference between the two target frequencies is 40 Hz or less. As the difference between the two target frequencies increases, the difference between the natural frequency of the first power generation element and each target frequency increases, so it becomes difficult to amplify the vibration over the entire range of the target frequency, but the difference between the two target frequencies. Is 40 Hz or less, in addition to the effect of any one of claims 1 to 3, there is an effect that power can be generated by amplifying vibrations over the entire range of the target frequency.

  According to the power generation device of the fifth aspect, the second rigid rod configured in a rod shape from the magnetic material is arranged to face the second magnetostrictive rod configured in a rod shape from the magnetostrictive material. A second coil is disposed on at least the second magnetostrictive rod of the second rigid rod and the second magnetostrictive rod, and one end side in the axial direction of the second magnetostrictive rod and the second rigid rod is supported by the second support member. The second support member is fixed to the vibrating body. The other end in the axial direction of the second magnetostrictive rod and the second rigid rod is held by the second mass member. The second mass member extends or contracts the second magnetostrictive rod and the second rigid rod in the axial direction by relative movement with the second support member. The second power generation element configured in this way is set between two target frequencies, which is different from the frequency exhibiting the largest vibration acceleration and different from the natural frequency of the first power generation element. Is done. Therefore, even when a vibration having a frequency different from the natural frequency of the second power generation element is applied from the vibrating body, the second power generation element can be vibrated to generate power. Therefore, in addition to the effect of any one of claims 1 to 4, there is an effect of further widening the range of frequencies that can be generated.

  According to the power generating element design method of the sixth aspect, the first rigid rod configured from the magnetic material in a rod shape is arranged to face the first magnetostrictive rod configured from the magnetostrictive material in a rod shape. A first coil is disposed on at least the first magnetostrictive rod of the first rigid rod and the first magnetostrictive rod, and one end side in the axial direction of the first magnetostrictive rod and the first rigid rod is supported by the first support member. The first support member is fixed to a vibrating body that outputs vibrations having a plurality of frequency components. The other ends in the axial direction of the first magnetostrictive rod and the first rigid rod are held by the first mass member. The first mass member extends or contracts the first magnetostrictive rod and the first rigid rod in the axial direction by relative movement with the first support member. The vibration component of the vibrating body to which the first support member of the first power generation element configured as described above is fixed is acquired by the vibration component acquisition step. Based on the vibration component acquired by the vibration component acquisition step, the natural frequency that is between two different target frequencies within the frequency range of vibration output by the vibrating body and different from the frequency indicating the largest vibration acceleration. Is set in the first power generation element by the natural frequency setting step. As a result, an effect similar to that of the first aspect can be obtained.

It is a schematic diagram of the electric power generating apparatus in 1st Embodiment of this invention. It is a schematic diagram which shows the relationship between the frequency of vibration and the generated voltage. It is a schematic diagram which shows the relationship between the frequency of vibration and the generated voltage. It is a schematic diagram which shows the relationship between the frequency of a vibration, and the natural frequency of an electric power generating apparatus. (A) is a schematic diagram of the power generator in 2nd Embodiment, (b) is a schematic diagram which shows the relationship between the frequency of a vibration, and the natural frequency of a power generator.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic diagram of a power generation device 10 according to a first embodiment of the present invention. As shown in FIG. 1, the power generation device 10 includes a first power generation element 11. The first power generation element 11 is composed of a magnetostrictive material (a kind of magnetic material) and a first magnetostrictive rod 13 around which a first coil 12 is wound, a first rigid rod 14 composed of a magnetic material, The first support member 15 is attached to one end side in the axial direction of the first magnetostrictive rod 13 and the first rigid rod 14, and is attached to the other end side in the axial direction of the first magnetostrictive rod 13 and the first rigid rod 14. The first mass member 16 is provided.

  The first coil 12 is a cylindrical member wound with a wire (conducting wire) made of copper wire, and is provided on the first magnetostrictive rod 13 with a gap provided between the first coil 12 and the first magnetostrictive rod 13. . The first magnetostrictive rod 13 and the first rigid rod 14 are formed in a long plate shape having a rectangular axis-perpendicular section having a large width with respect to the thickness. The first magnetostrictive rod 13 and the first rigid rod 14 are formed in substantially the same shape (dimension) with each other, and are arranged in parallel with opposing large planes (that is, planes including the width). The first rigid rod 14 is made of a magnetic material having a magnetostriction effect lower than that of the first magnetostrictive rod 13. In the present embodiment, the first magnetostrictive rod 13 is made of an iron gallium alloy, and the first rigid rod 14 is made of a steel material. A bias magnetic field is applied to the first magnetostrictive rod 13 and the first rigid rod 14 by a permanent magnet (not shown) attached between the first magnetostrictive rod 13 and the first rigid rod 14. A magnetic closed circuit is formed in the first power generating element 11 by the magnetostrictive rod 13, the first rigid rod 14, and the permanent magnet.

  The vibrating body 17 is a member to which the first support member 15 is fixed, and outputs vibrations having a plurality of frequency components. The vibration body 17 includes a vehicle body (frame), a subframe such as a suspension member and a side member, various parts such as a suspension link and a suspension arm, an engine, and a vibration isolator such as a torque rod that elastically supports the engine on the vehicle body. Illustrated.

  The first power generation element 11 is installed in a state where the first support member 15 side is a fixed end and the first mass member 16 side is a free end with respect to the vibration body 17. The rod 13 and the first rigid rod 14 are used by vibrating in a plane where the rod 13 and the first rigid rod 14 are located. In this case, axial extension and contraction are generated in the first magnetostrictive rod 13 and the first rigid rod 14 due to bending deformation accompanying vibration, so that the first magnetostrictive rod 13 and the first rigid rod 14 are parallel to the axial direction. Electric power is generated by changing the magnetic flux density in the direction and generating a current in the first coil 12.

  The first power generation element 11 is a vibrating body having a natural frequency mainly determined by the mass of the first mass member 16 and the spring constants of the first magnetostrictive rod 13 and the first rigid rod 14. When the resonance frequency of the first power generation element 11 is applied from the vibrating body 17 to the first power generation element 11, the vibration is amplified. As a result, the change in magnetic flux density penetrating the first coil 12 becomes large, so that the generated voltage can be increased. A large generated voltage can be obtained by matching the frequency indicating the largest vibration acceleration among the vibrations input to the vibrating body 17 with the natural frequency of the first power generation element 11.

  However, since the vibrating body 17 also outputs vibrations having frequency components other than the resonance frequency of the first power generation element 11, there is a problem that vibrations of frequency components other than the resonance frequency are difficult to be used for power generation. In addition, when the frequency indicating the largest vibration acceleration is matched with the natural frequency of the first power generation element 11, the first power generation element 11 resonates and the amplitude of the first power generation element 11 increases, so that the first magnetostrictive rod 13 and the first rigidity are increased. There is a problem that the rod 14 is easily damaged. In order to solve these problems, the first power generating element 11 has a unique characteristic that is between two different target frequencies within the frequency range of vibration output by the vibrating body 17 and different from the frequency that exhibits the largest vibration acceleration. The frequency is set.

  Hereinafter, with reference to FIG. 2, the relationship between the frequency of vibration output from the vibrating body 17, the natural frequency fn of the first power generation element 11, and the generated voltage of the power generation device 10 will be described in detail. FIG. 2 is a schematic diagram showing the relationship between vibration frequency and generated voltage. In FIG. 2, the horizontal axis represents frequency (Hz). The frequency component of the vibration of the vibrating body 17 is obtained by obtaining vibration information including the displacement and speed of the vibrating body 17 from a vibration sensor (not shown) installed on the vibrating body 17 and then converting the vibration information to a fast Fourier transform (hereinafter “ It can be obtained by processing by “FFT”). FFT is an algorithm for calculating discrete Fourier transform at high speed on a computer. In the present embodiment, as a result of performing FFT processing on the vibration information of the vibrating body 17, the vibration output from the vibrating body 17 has a vibration component in which peaks appear at the frequency f1 and the frequency f2. Frequency f1 <frequency f2, and acceleration (vibration acceleration) at frequency f1 is larger than acceleration (vibration acceleration) at frequency f2.

  The first power generation element 11 has a natural frequency set to fn. In the present embodiment, the natural frequency fn is set to the same magnitude as the frequency f2 that appears as a peak between the two target frequencies f1 and f3 (f1 <f2 = fn <f3). The target frequencies f1 and f3 are within a frequency range in which the resonance magnification (transmissibility during resonance) of the first power generation element 11 is equal to or higher than a predetermined value A (5 times in the present embodiment), and the vibration component of the vibrating body 17 is Arbitrarily set to the range of frequencies that appear. Further, the target frequencies f1 and f3 are set such that the difference (f3−f1) is 40 Hz or less.

  Here, the natural frequency fn of the first power generation element 11 is set to a frequency f2 between the target frequencies f1 and f3 and different from the frequency f1 indicating the largest vibration acceleration. By setting the natural frequency fn of the first power generation element 11 in this way, when a vibration having a frequency (for example, f2 or f3) different from the natural frequency fn is applied from the vibrating body 17 to the first power generation element 11 In addition, the first power generation element 11 can be vibrated to generate power (see FIG. 2). In addition, power can be generated when vibration of frequency f1 is applied to the first power generation element 11 (see FIG. 2). Therefore, the range of frequencies that can be generated can be widened. In this case, it is only necessary to set the natural frequency fn of the first power generation element 11, and a separate component such as a dynamic damper can be dispensed with, so that the frequency range in which power can be generated can be widened while suppressing an increase in the number of components. In addition, since the target frequencies f1 and f3 are set in a frequency range in which the resonance magnification of the first power generation element 11 is 5 times or more and a frequency range in which the vibration component of the vibration body 17 appears by FFT processing, the vibration of the vibration body 17 It is possible to reliably generate power with the output of.

  Here, when the natural frequency fn of the first power generation element 11 is set to the frequency f1 having the largest vibration acceleration between the target frequencies f1 and f3, the first power generation element 11 resonates and the amplitude becomes maximum. In this case, the first magnetostrictive rod 13 and the first rigid rod 14 are easily damaged. However, by setting the natural frequency fn to the frequency f2 where the vibration acceleration is smaller than the frequency f1, the amplitude of the first power generation element 11 at the frequencies f1 and f2 can be suppressed, so the first magnetostrictive rod 13 and the first rigid rod 14 Can be hard to break. Therefore, the durability of the first power generation element 11 can be ensured.

  Further, since the difference (f3-f1) between the target frequencies f1 and f3 is set to 40 Hz or less, the resonance magnification of the first power generating element 11 (for example, a resonance magnification of 5 times or more) in the entire range of the target frequencies f1 and f3 Can be secured. Therefore, power can be generated by amplifying the vibration in the entire range of the target frequencies f1 and f3. As a result, it is possible to prevent the first magnetostrictive rod 13 and the first rigid rod 14 from being easily damaged by excessive vibration while securing the generated voltage.

  More preferably, the difference (f3-f1) between the target frequencies f1 and f3 is set to 30 Hz or less. This is because by setting the difference between the target frequencies f1 and f3 to 30 Hz or less, the resonance magnification near the target frequencies f1 and f3 can be increased as compared with the case where the difference between the target frequencies f1 and f3 is set to 40 Hz or less.

  The natural frequency fn of the first power generation element 11 is at least one of the magnitudes of the two target frequencies f1 and f3, the magnitude of vibration acceleration at the target frequencies f1 and f3, and the frequency of occurrence of each frequency component of vibration. It is set based on the conditions. The natural frequency fn can be obtained by a simple average of the magnitudes of the target frequencies f1 and f3, a weighted average calculated by weighting the magnitude and occurrence frequency of vibration acceleration at the target frequencies f1 and f3, and the like.

  In the present embodiment, the natural frequency fn is not set to the simple average value of the target frequencies f1 and f3, but a peak (frequency f2) that appears near the target frequency f3 on the higher frequency side of the target frequencies f1 and f3. Is set to the natural frequency fn. Since the generated voltage of the power generation device 10 is proportional to the natural frequency fn of the first power generation element 11, setting the natural frequency fn closer to the target frequency f3 on the high frequency side allows the target frequency on the low frequency side to be set. Compared with the case where the natural frequency fn is set closer to f1, the generated voltage of the power generation apparatus 10 can be increased.

  Next, a modification of the first embodiment will be described with reference to FIG. Since this modification is the same as that of the first embodiment except for the vibration component output by the vibrating body 17, the same parts as those of the first embodiment are denoted by the same reference numerals and the following description is omitted. FIG. 3 is a schematic diagram showing the relationship between the frequency of vibration output from the vibrating body 17 (see FIG. 1) and the voltage generated by the power generation apparatus 10. As a result of the FFT processing of the vibration information of the vibrating body 17, the vibration output from the vibrating body 17 has a vibration component in which peaks appear at the frequency f4 and the frequency f5. Frequency f4 <frequency f5, and acceleration (vibration acceleration) at frequency f4 is greater than acceleration (vibration acceleration) at frequency f5.

  In the first power generation element 11 (see FIG. 1), the natural frequency fn is set to a simple average value of the two target frequencies f4 and f5 (f4 <fn <f5). The target frequencies f4 and f3 are within a frequency range in which the resonance magnification of the first power generation element 11 (transmissibility at the time of resonance) is equal to or greater than a predetermined value A (5 times in this embodiment), and the vibration component of the vibrating body 17 is Arbitrarily set to the range of frequencies that appear. In addition, the target frequencies f4 and f5 are set such that the difference (f5-f4) is 40 Hz or less.

  Similarly to the first embodiment, the natural frequency fn of the first power generation element 11 is set to a frequency that is between the target frequencies f4 and f5 and different from the frequency f4 indicating the largest vibration acceleration. By setting the natural frequency fn of the first power generation element 11 in this manner, even when vibrations of the target frequencies f4 and f5 are applied, the first power generation element 11 can be vibrated to generate power. Therefore, the range of frequencies that can be generated can be widened. Moreover, since the natural frequency fn is set in the valley portion between adjacent peaks, the generated voltage can be secured while suppressing the amplitude of the first power generation element 11 at the frequencies f4 and f5 and ensuring the durability.

  Next, another modification of the first embodiment will be described with reference to FIG. Since this modification is the same as that of the first embodiment except for the vibration component output by the vibrating body 17, the same parts as those of the first embodiment are denoted by the same reference numerals and the following description is omitted. FIG. 4 is a schematic diagram showing the relationship between the frequency of vibration output from the vibrating body 17 (see FIG. 1) and the natural frequency fn of the first power generation element 11. As a result of the FFT processing of the vibration information of the vibrating body 17, the vibration output from the vibrating body 17 has a vibration component in which peaks appear at the frequency f6 and the frequency f7. Frequency f6 <frequency f7, and acceleration (vibration acceleration) at frequency f6 is greater than acceleration (vibration acceleration) at frequency f7.

  In the first power generation element 11 (see FIG. 1), the natural frequency fn is set near the target frequency f7 between the two target frequencies f6 and f7 (f6 <fn <f7). The target frequencies f6 and f7 are arbitrarily set within a frequency range in which the resonance magnification of the first power generation element 11 (resonance rate during resonance) is 5 times or more and a frequency range in which the vibration component of the vibrating body 17 appears. . The target frequencies f6 and f7 are set such that the difference (f7−f6) is 40 Hz or less.

  As in the first embodiment, the natural frequency fn of the first power generation element 11 is set to a frequency that is between the target frequencies f6 and f7 and different from the frequency f7 that indicates the largest vibration acceleration. In addition, since the natural frequency fn is set in the valley portion between adjacent peaks, the generated voltage can be secured while suppressing the amplitude of the first power generation element 11 at the frequencies f6 and f7 and ensuring the durability. Furthermore, since the natural frequency fn is set closer to the target frequency f7 on the high frequency side, the generated voltage can be increased compared to the case where the natural frequency fn is set closer to the target frequency f6 on the low frequency side. This is because the generated voltage is proportional to the natural frequency fn.

  Next, a second embodiment will be described with reference to FIG. In the first embodiment, the power generation device 10 in which one power generation element (first power generation element 11) is installed in the vibrating body 17 has been described. On the other hand, in 2nd Embodiment, the electric power generating apparatus 20 with which two electric power generation elements are installed in the vibrating body 27 is demonstrated. In addition, about the part same as the part demonstrated in 1st Embodiment, the same code | symbol is attached | subjected and the following description is abbreviate | omitted. FIG. 5A is a schematic diagram of the power generation device 20 in the second embodiment, and FIG. 5B is a relationship between the vibration frequency output from the vibrating body 27 and the natural frequencies fn and fo of the power generation device 20. It is a schematic diagram which shows.

  As shown in FIG. 5A, the power generation device 20 includes a first power generation element 11 and a second power generation element 21. The second power generation element 21 is composed of a magnetostrictive material (a kind of magnetic material) and a second magnetostrictive rod 23 around which a second coil 22 is wound, a second rigid rod 24 composed of a magnetic material, The second support member 25 attached to one end side in the axial direction of the second magnetostrictive rod 23 and the second rigid rod 24 and the other end side in the axial direction of the second magnetostrictive rod 23 and the second rigid rod 24 are attached. And a second mass member 26.

  The second coil 22 is a cylindrical member around which a wire (conductive wire) made of copper wire is wound, and is provided on the second magnetostrictive rod 23 with a gap provided between the second coil 22 and the second magnetostrictive rod 23. . The 2nd magnetostrictive rod 23 and the 2nd rigid rod 24 are formed in the elongate plate shape which has a rectangular axial cross section with a large width | variety with respect to thickness. The second magnetostrictive rod 23 and the second rigid rod 24 are formed in substantially the same shape (dimension) with each other, and are arranged in parallel with opposing large planes (that is, planes including the width). The second rigid rod 24 is made of a magnetic material having a magnetostriction effect lower than that of the second magnetostrictive rod 23. In the present embodiment, the second magnetostrictive rod 23 is made of an iron gallium alloy, and the second rigid rod 24 is made of a steel material. A bias magnetic field is applied to the second magnetostrictive rod 23 and the second rigid rod 24 by a permanent magnet (not shown) attached between the second magnetostrictive rod 23 and the second rigid rod 24. A magnetic closed circuit is formed in the second power generating element 21 by the magnetostrictive rod 23, the second rigid rod 24 and the permanent magnet.

  The vibrating body 27 is a member to which the second support member 25 and the first support member 15 of the first power generation element 11 are fixed, and outputs vibration having a plurality of frequency components. The second power generation element 21 is installed with the second support member 25 side as a fixed end and the second mass member 26 side as a free end with respect to the vibration body 27, and the second magnetostriction is generated along with the vibration of the vibration body 27. It is used by vibrating in the plane where the rod 23 and the second rigid rod 24 are located. In this case, axial expansion and contraction occur in the second magnetostrictive rod 23 and the second rigid rod 24 due to bending deformation caused by vibration, so that the second magnetostrictive rod 23 and the second rigid rod 24 are parallel to the axial direction. Electric power is generated by changing the magnetic flux density in the direction and generating a current in the second coil 22.

  The second power generation element 21 is a vibrating body having a natural frequency fo mainly determined by the mass of the second mass member 26 and the spring constants of the second magnetostrictive rod 23 and the second rigid rod 24. When the resonance frequency of the second power generation element 21 is applied from the vibrating body 27 to the second power generation element 21, the vibration is amplified. As a result, the change in magnetic flux density penetrating through the second coil 22 is increased, so that the generated voltage can be increased.

  As shown in FIG. 5B, as a result of the FFT processing of the vibration information of the vibrating body 27, the vibration output from the vibrating body 27 has a vibration component in which a peak appears at the frequency f8 and the frequency f8. Frequency f8 <frequency f9, and acceleration (vibration acceleration) at frequency f8 is greater than acceleration (vibration acceleration) at frequency f9.

  In the first power generation element 11, the natural frequency fn is set near the target frequency f8 between the two target frequencies f8 and f9. In the second power generation element 21, the natural frequency fo is set near the target frequency f9 between the target frequencies f8 and f9 (f8 <fn <fo <f9). The target frequency f8 is arbitrarily set within a frequency range in which the resonance magnification (transmission rate at the time of resonance) of the first power generating element 11 is 5 times or more and a frequency range in which the vibration component of the vibrating body 27 appears. The target frequency f9 is arbitrarily set within a frequency range in which the resonance magnification (transmission rate at the time of resonance) of the second power generating element 21 is 5 times or more and a frequency range in which the vibration component of the vibrating body 27 appears. The target frequencies f8 and f9 are set such that the difference (f9−f8) is greater than 40 Hz and 80 Hz or less.

  The natural frequency fn of the first power generation element 11 and the natural frequency fo of the second power generation element 21 are between the target frequencies f8 and f9 and are different from the frequency f8 and fo, which are different from the frequency f8 indicating the largest vibration acceleration. Is set. By setting the natural frequencies fn and fo of the power generation device 20 in this way, when vibrations having frequencies different from the natural frequencies fn and fo (for example, f8 and f9) are applied from the vibrating body 27 to the power generation device 20. In addition, the first power generation element 11 and the second power generation element 21 can be vibrated to generate power. Therefore, the range of frequencies that can be generated can be widened.

  In addition, since the difference (f9−f8) is set to be over 80 Hz and below 80 Hz in the target frequencies f8 and f9, compared with the first embodiment, vibrations in a wider range of frequency components are used for power generation. it can. In addition, since the first power generation element 11 and the second power generation element 21 can secure resonance magnifications around the target frequencies f8 and f9 (for example, resonance magnifications of 5 times or more), respectively, vibrations are generated over the entire range of the target frequencies f8 and f9. Amplified to generate electricity. As a result, it is possible to prevent the power generation device 20 from being easily damaged by excessive vibration while expanding the frequency band in which the generated voltage can be secured.

  The present invention has been described above based on the embodiments. However, the present invention is not limited to the above embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. It can be easily guessed. For example, the numerical values given in the above embodiment are merely examples, and other numerical values can naturally be adopted.

  In each of the above embodiments, when the first coil 12 or the second coil 22 (hereinafter referred to as “coil”) is wound around the first magnetostrictive rod 13 or the second magnetostrictive rod 23 (hereinafter referred to as “magnetostrictive rod”). However, the present invention is not necessarily limited thereto, and coils may be wound around both the magnetostrictive rod, the first rigid rod 14, and the second rigid rod 24 (hereinafter referred to as "rigid rod"). In this case, the magnetostrictive rod and the rigid rod are made of the same magnetostrictive material (that is, the rigid rod need not be made of a material having a magnetostriction effect lower than that of the magnetostrictive rod). Moreover, it is not restricted to a cylindrical coil, Of course, it is possible to employ | adopt a planar coil.

  In each of the above embodiments, the case where the permanent magnet is disposed between the magnetostrictive rod and the rigid rod has been described, but the present invention is not necessarily limited thereto. For example, instead of a permanent magnet, an electromagnet can be used. In addition, if the magnetic flux from the outside of the first power generation element 11 or the second power generation element 21 is generated in the magnetic circuit, a magnet is placed outside the first power generation element 11 or the second power generation element 21. It is possible to have an arrangement. It is also possible to provide a back yoke that applies a bias magnetic field to the magnetostrictive rod and rigid rod by the magnetomotive force of a permanent magnet or electromagnet.

  In each of the above-described embodiments, the case where the dimensions (that is, the thickness and the width) of the magnetostrictive rod and the rigid rod are substantially the same has been described. However, the present invention is not necessarily limited to this. The bar dimensions may be different values (one or both of the thickness and width differ).

  In each of the above-described embodiments, the case where the magnetostrictive rod and the rigid rod are formed in a rectangular cross section has been described. However, the present invention is not necessarily limited to this, and other shapes are naturally possible. Examples of other shapes include a square cross section, a circular cross section, an elliptical cross section, and a polygonal cross section (for example, a hexagonal cross section).

  For example, if the magnetostrictive rod or the like has a circular cross section, the permanent magnet is brought into line contact, and if the contact area cannot be secured, the size or magnetomotive force of the permanent magnet is increased or the magnetostrictive rod or the like is permanently attached. It is preferable to secure a contact area by interposing a spacer made of a magnetic material between the magnet and a shape corresponding to both shapes (that is, a shape in surface contact with both). This is because the bias magnetic field that can be applied can be increased.

  In the second embodiment, the case where two power generation elements (the first power generation element 11 and the second power generation element 21) are installed in the vibration body 27 has been described. However, the frequency band of vibration output from the vibration body 27 is not limited. In the case of a large area, it is naturally possible to install three or more power generating elements according to the width of the band.

DESCRIPTION OF SYMBOLS 10,20 Power generation device 11 1st power generation element 12 1st coil 13 1st magnetostriction rod 14 1st rigid rod 15 1st support member 16 1st mass member 17, 27 Vibrating body 21 2nd power generation element 22 2nd coil 23 1st 2 Magnetostrictive rod 24 2nd rigid rod 25 2nd support member 26 2nd mass member f1, f3, f4, f5, f6, f7, f8, f9 Target frequency fn, fo Natural frequency

Claims (6)

A first magnetostrictive rod configured in a rod shape from a magnetostrictive material;
A first rigid bar configured in a rod shape from a magnetic material and disposed opposite to the first magnetostrictive bar;
A first coil disposed on at least the first magnetostrictive rod of the first rigid rod and the first magnetostrictive rod;
A first support member that supports one end side in the axial direction of the first magnetostrictive rod and the first rigid rod, and is fixed to a vibrating body that outputs vibration having a plurality of frequency components;
The other ends of the first magnetostrictive rod and the first rigid rod are held in the axial direction, and the first magnetostrictive rod and the first rigid rod are extended or contracted in the axial direction by relative movement with the first support member. A first power generation element including a first mass member;
The first power generating element has a natural frequency that is between two different target frequencies within a frequency range of vibration output by the vibrating body and different from a frequency that indicates the largest vibration acceleration. A power generator characterized by the above.   The natural frequency is set based on one or more of the magnitudes of the two target frequencies, the magnitude of vibration acceleration at the two target frequencies, and the occurrence frequency of a plurality of vibrations. The power generator according to claim 1.   The power generation apparatus according to claim 1 or 2, wherein the natural frequency is set closer to a target frequency on a higher frequency side of the two target frequencies.   The power generator according to any one of claims 1 to 3, wherein a difference between the two target frequencies is 40 Hz or less. A second magnetostrictive rod configured in a rod shape from a magnetostrictive material;
A second rigid rod configured in a rod shape from a magnetic material and disposed opposite to the second magnetostrictive rod;
A second coil disposed on at least the second magnetostrictive rod of the second rigid rod and the second magnetostrictive rod;
A second support member that supports one end side in the axial direction of the second magnetostrictive rod and the second rigid rod and is fixed to the vibrating body;
The other ends of the second magnetostrictive rod and the second rigid rod are held in the axial direction, and the second magnetostrictive rod and the second rigid rod are extended or contracted in the axial direction by relative movement with the second support member. A second power generation element including a second mass member;
The second power generation element is set to a natural frequency that is between the two target frequencies, is different from a frequency indicating the largest vibration acceleration, and is different from a natural frequency of the first power generation element. The power generation device according to any one of claims 1 to 4, wherein: A first magnetostrictive rod configured in a rod shape from a magnetostrictive material;
A first rigid bar configured in a rod shape from a magnetic material and disposed opposite to the first magnetostrictive bar;
A first coil disposed on at least the first magnetostrictive rod of the first rigid rod and the first magnetostrictive rod;
A first support member that supports one end side in the axial direction of the first magnetostrictive rod and the first rigid rod, and is fixed to a vibrating body that outputs vibration having a plurality of frequency components;
The other ends of the first magnetostrictive rod and the first rigid rod are held in the axial direction, and the first magnetostrictive rod and the first rigid rod are extended or contracted in the axial direction by relative movement with the first support member. A vibration component acquisition step of acquiring a vibration component of the vibrating body to which the first support member of the first power generation element including the first mass member is fixed;
Based on the vibration component acquired by the vibration component acquisition step, the frequency is different between two different target frequencies within the frequency range of vibration output by the vibrating body, and is different from the frequency indicating the largest vibration acceleration. A power generator design method comprising: a natural frequency setting step of setting a frequency in the first power generation element.

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