JP5936514B2 - Power generation unit - Google Patents

Description

  The present invention relates to a power generation unit that generates power using vibration of a mounted vibration source, and more particularly to a power generation unit that can efficiently generate power in a vibration source having a relatively low frequency of vibration. is there.

  Patent Document 1 discloses a power generation element that performs vibration power generation using the inverse magnetostriction effect of a magnetostrictive material. This power generation element will be described with reference to FIG. FIG. 5A is a front view of a conventional power generation element 901, and FIG. 5B is a side view of the power generation element 901 viewed in the direction of arrow Vb in FIG. 5A. 5A schematically shows a state where the magnetostrictive rods 911 and 912 are expanded or shortened, and illustration of the coil 931, the permanent magnets 941 and 942 and the back yoke 950 is omitted.

  As shown in FIG. 5A, the power generation element 901 includes a pair of magnetostrictive rods 911 and 912, a first yoke 921 that supports one end of the pair of magnetostrictive rods 911 and 912, and a pair of magnetostrictive rods 911 and 912. And a pair of coils 931 and 932 wound around a pair of magnetostrictive rods 911 and 912 (note that the coil 932 is not shown). ), And a pair of permanent magnets 941 and 942 disposed on the back surfaces of one end and the other end of the pair of magnetostrictive rods 911 and 912, respectively, and a pair of the permanent magnets 941 and 942 connected to each other. The back yoke 950 for applying a bias magnetic field to the magnetostrictive rods 911 and 912 is mainly provided.

  The power generation element 901 is installed with the first yoke 921 fixed to the vibration source and the second yoke 922 as a free end, and is moved in the direction perpendicular to the axis of the magnetostrictive rods 911 and 912 as the vibration source vibrates. By causing the two yokes 922 to perform pendulum movement (free vibration), axial expansion and contraction are generated in one and the other of the magnetostrictive rods 911 and 912, respectively. That is, as shown in FIG. 5 (a), the magnetostrictive rods 911 and 912 are bent and deformed by the pendulum movement, so that one (magnetostrictive rod 911) contracts in the axial direction and the other (magnetostrictive rod 912) axially. Each directional stretch is generated. As a result, the magnetic flux density changes in a direction parallel to the axial direction of the magnetostrictive rods 911 and 912 (inverse magnetostrictive effect), current is generated in the coils wound around the magnetostrictive rods 911 and 912, and power generation is performed.

  The mass of the movable mass and the spring constant are set so that the power generation element 901 resonates under the installation environment (vibration of the vibration source). For example, the second yoke 922 is enlarged to increase the mass as a movable mass, or the axial lengths of the magnetostrictive rods 911 and 912 are increased, and the magnetostrictive rods 911 and 912 are decreased in thickness. The resonance frequency of the power generation element 901 can be adjusted to the low frequency side by narrowing the facing distance between the bars 911 and 912 and reducing the spring constant, while the reverse can be adjusted to the high frequency side.

PCT / JP2011 / 003276 (paragraph 0078, FIG. 4A, etc.)

  However, with the power generation element 901 described above, it is difficult to efficiently generate power for a vibration source (for example, a bridge, a footbridge, or a road that vibrates at about 3 Hz to 20 Hz) whose vibration is relatively low. There was a problem that.

  That is, when the second yoke 922 is enlarged to increase the mass of the movable mass, the volume of the portion unrelated to the power generation increases, so that the power density (power that can be taken out per unit volume) decreases. Increasing the axial length of the magnetostrictive rods 911, 912 to reduce the spring constant leads to an increase in the size of the entire power generating element 901, and reducing the thickness of the magnetostrictive rods 911, 912 makes it easier for magnetic flux to leak, resulting in the amount of power generation. If the facing distance between the magnetostrictive rods 911 and 912 is narrowed, the coil arrangement space is reduced and the number of turns cannot be secured, so the amount of power generation is reduced. In the first place, since the generated voltage of the power generation element 901 is proportional to the frequency, the power generation efficiency decreases as the vibration of the vibration source becomes lower in frequency.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power generation unit that can efficiently generate power in a vibration source having a relatively low frequency of vibration. .

Means for Solving the Problems and Effects of the Invention

  According to the power generation unit of claim 1, the mass member is provided on the fixed member fixed on the vibration source side and is elastically supported by the elastic support member so as to freely vibrate, and the resonance frequency of the vibration device is provided. The first frequency is lower than the second frequency, which is the resonance frequency of the power generation element, so that the vibration device is resonated by matching the resonance frequency (first frequency) of the vibration device with the vibration of the vibration source. The mass member can periodically collide with the other end of the magnetostrictive rod of the power generating element. Thereby, free vibration can be generated on the other end side of the magnetostrictive rod, and the power generation element can efficiently generate power.

  In other words, the resonance frequency (second frequency) of the power generation element does not need to be adjusted to the vibration of the vibration source and can be set to a high frequency, so that power generation can be performed while securing the generation voltage of the power generation element. it can. As a result, power generation can be performed efficiently in a vibration source having a relatively low frequency of vibration.

  Further, if the resonance frequency (second frequency) of the power generating element can be set to a high frequency, for example, the volume of the portion that becomes the movable mass can be reduced and the length of the magnetostrictive rod can be shortened. The entire power generation unit can be reduced in size.

  According to the power generation unit of claim 2, in addition to the effect produced by the power generation unit of claim 1, a pair of permanent magnets are sandwiched between the first rod and the second rod with different magnetic poles. A magnetic loop is formed by the first rod and the second rod and the pair of permanent magnets, and a bias magnetic field by the magnetomotive force of the permanent magnet is applied to the first rod and the second rod. Therefore, the first rod and the second rod are expanded or contracted by free vibration at the other end in the axial direction, whereby the magnetic flux density is changed in a direction parallel to the axial direction. As a result, a current is generated in the coil wound around at least one of the first rod and the second rod, and power generation is performed.

  In this case, according to the second aspect, as described above, since the resonance frequency (second frequency) of the power generation element can be set to a high frequency by providing the vibration generator, the other axial end becomes a movable mass. The mass of the holding member on the side can be reduced. Thereby, since the volume of the part unrelated to power generation can be suppressed, the power density (the power that can be extracted from the unit volume) can be increased accordingly. In addition, the spring constant of the power generating element can be increased. Thereby, since the axial direction length of a 1st rod and a 2nd rod can be shortened, size reduction of an electric power generation unit can be achieved by that much. Similarly, since the thickness and diameter of the first rod and the second rod can be increased, the magnetic flux can hardly be leaked, and the facing distance between the first rod and the second rod can be increased, so that a space for arranging the coil is ensured. The number of turns can be increased, and the power generation efficiency can be improved accordingly.

  Here, according to the second aspect, the permanent magnet is sandwiched between the opposed first and second rods, and the permanent magnet is sandwiched between the opposed first and second rods. Since it is held by the holding member (that is, the axial direction one end side and the other end side of the first rod and the second rod in which the permanent magnet is sandwiched are respectively held by the holding member), the first rod and the second rod during power generation It is possible to suppress the occurrence of slipping between the two bars and the permanent magnet, and to reduce energy loss due to frictional resistance. Furthermore, a magnetic loop can be formed by the first and second rods and the permanent magnet, and there is no need to attach a back yoke as in the prior art, so that the number of parts can be reduced and the size can be reduced accordingly. it can. Therefore, according to the second aspect, it is possible to improve the power generation efficiency while reducing the number of parts and reducing the size.

  According to the power generating element of the third aspect, in addition to the effect of the power generating element of the second aspect, there is an effect that the power generation efficiency can be improved while reducing the number of parts. That is, since the coil is wound only around the first rod and the coil does not need to be wound around the second rod, the number of parts can be reduced accordingly. Further, if it is not necessary to wind the coil around the second rod, the number of turns of the coil wound around the first rod can be increased by using the space for winding the coil around the second rod. The power generation efficiency can be improved accordingly. Furthermore, as described above, since the resonance frequency (second frequency) of the power generation element can be set to a high frequency and the spring constant of the power generation element can be increased by providing the vibration generator, the first rod and the second rod Can be widened. Also from this point, it is possible to increase the number of turns of the coil and improve the power generation efficiency.

  Here, in a structure in which a pair of permanent magnets are sandwiched between the first and second rods facing each other with different magnetic poles, and a magnetic loop is formed by the first and second rods and the pair of permanent magnets. The direction of the magnetic field formed along the axial direction of the first bar is opposite to the direction of the magnetic field formed along the axial direction of the second bar. Therefore, during power generation, when the first rod and the second rod are extended or contracted, the change in magnetic flux density in the direction parallel to the axial direction is reversed and cancels each other. Therefore, the change in magnetic flux density is reduced, resulting in a decrease in power generation efficiency.

  On the other hand, according to the third aspect, since the second rod (that is, the coil is not wound) is made of a magnetostrictive material having a magnetostriction effect lower than that of the first rod, When the two bars are expanded or contracted, the change in magnetic flux density in the direction parallel to the axial direction of the second bar can be reduced. Therefore, the change in the magnetic flux density in the direction parallel to the axial direction of the first rod can be suppressed from canceling out the change in the magnetic flux density in the direction parallel to the axial direction of the first rod. The change in magnetic flux density in the direction parallel to the axial direction of the first rod can be ensured to improve the power generation efficiency.

  In addition, the second rod does not need to be made of a magnetostrictive material having a high magnetostriction effect, and can be made of a general magnetic material. As a product cost can be reduced.

  According to the power generating element of claim 4, in addition to the effect produced by the power generating element of claim 2 or 3, the fixing member of the vibration exciter is formed integrally with the holding member of the power generating element. As compared with the case where the power generator is separated, the number of parts can be reduced and the assembly process can be simplified, and the product cost of the power generation unit as a whole can be reduced accordingly.

It is a partial section front view of the power generation unit in a 1st embodiment of the present invention. (A) is a top view of a vibrating device, (b) is a top view of a power generation element. It is a front view of the electric power generation unit in 2nd Embodiment. It is a front view of the electric power generation unit in 3rd Embodiment. (A) is a front view of the conventional electric power generation element, (b) is a side view of the electric power generation element in the arrow Vb direction view of Fig.5 (a).

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a partial cross-sectional front view of a power generation unit 1 according to a first embodiment of the present invention. FIG. 2A is a top view of the vibrating device 70, and FIG. 2B is a top view of the power generation element 10. In FIG. 1, in order to help understanding of the orientation of the magnetic poles of the permanent magnets 31 and 32, the magnetism is shown in the drawing for the sake of convenience using the notation “N” and “S”.

  As shown in FIGS. 1 and 2, the power generation unit 1 is installed with one holding member 60 (the right side in FIG. 1) of the pair of holding members 60 fixed to the vibration source SV. One end side in the axial direction of the second rod 12 (right side in FIG. 1) is a fixed end, and the other end side in the axial direction (left side in FIG. 1) of the first rod 11 and second rod 12 is a free end capable of free vibration. Is done. When the vibration source SV is vibrated, the other holding member 60 (left side in FIG. 1) is caused to perform a pendulum motion (free vibration) by the vibration, thereby generating electric power. That is, the first rod 11 is stretched and contracted in the axial direction due to bending deformation accompanying the pendulum motion, and the magnetic flux density changes in a direction parallel to the axial direction of the first rod 11, so that current is supplied to the coil 20. Generated and power is generated.

  In addition, the mounting target of the power generation unit 1 is a vibration source SV whose vibration is relatively low frequency (for example, about 3 Hz to 20 Hz). Examples of such a vibration source SV include a bridge, a pedestrian crossing, and a road. Etc. are illustrated as an example. In the present embodiment, the description will be made assuming that the vibration of the vibration source SV is 10 Hz.

  The power generation unit 1 includes a power generation element 10 and a vibration device 70 connected to the power generation element 10. The power generating element 10 includes a first rod 11 and a second rod 12 made of a magnetostrictive material, a coil 20 wound around the first rod 11, and the other axial end side of the first rod 11 and the second rod 12. A pair of permanent magnets 31 and 32 sandwiched between the first rod 11 and the second rod 12 facing each other (on the left side in FIG. 1) and one axial end side (the right side in FIG. 1), the first rod 11 and the second rod. A pair of holding members 60 that are attached to one end side and the other end side of the rod 12 in the axial direction and hold the state in which the permanent magnets 31 and 32 are sandwiched between the first rod 11 and the second rod 12 facing each other. Prepare.

  The first rod 11 and the second rod 12 are cross-sectional rectangles having a larger width dimension (vertical dimension in FIG. 2 (b)) than the thickness dimension (vertical dimension in FIG. 1) (that is, the cross section has a long side (in the width direction). (Long side) and a short side (rectangular shape having a side along the thickness direction).

  The first rod 11 and the second rod 12 are formed in the same shape (dimension) with each other, and are arranged in parallel with side surfaces having a large area (that is, side surfaces including long sides in the cross section) facing each other. The second rod 12 is made of a magnetostrictive material having a magnetostriction effect lower than that of the first rod 11. In the present embodiment, the first rod 11 is made of an iron gallium alloy, and the second rod 12 is made of a steel material.

  The coil 20 is a coil obtained by winding a wire made of copper wire around the first rod 11. A gap is provided between the coil 20 and the first rod 11. The permanent magnets 31 and 32 are members (permanent magnets) for applying a bias magnetic field to the first rod 11 and are each formed in a plate shape having a rectangular cross section.

  The permanent magnets 31 and 32 are arranged with different magnetic poles. That is, the permanent magnet 31 has an N pole on the surface connected to the first rod 11 (upper side in FIG. 1) and an S pole on the surface connected to the second rod 12 (lower side in FIG. 1). On the contrary, the permanent magnet 32 has an S pole on the surface connected to the first rod 11 and an N pole on the surface connected to the second rod 12.

  Accordingly, a magnetic loop is formed by the first rod 11, the second rod 12, and the permanent magnets 31 and 32, and a bias magnetic field due to the magnetomotive force of the permanent magnets 31 and 32 is applied to the first rod 11. As a result, the easy magnetization direction (the direction of magnetization or the direction in which magnetization is likely to occur) of the first rod 11 is set to the axial direction (longitudinal direction, left-right direction in FIG. 1) of the first rod 11.

  The permanent magnets 31 and 32 are disposed in a storage space formed (recessed) in the fixed member 40. A gap is formed between the inner surface of the housing space and the side surfaces of the first rod 11 and the second rod 12 and the side surfaces of the permanent magnets 31 and 32, and the permanent magnets 31, 32 is fixed to the fixing member 40.

  The holding member 60 includes a pair of fixing members 40 that are respectively attached to one end side and the other end side in the axial direction of the first rod 11 and the second rod 12, and a holder member 50 into which the pair of fixing members 40 are press-fitted. With. The fixing member 40 and the holder member 50 are made of a nonmagnetic material (in this embodiment, an aluminum alloy).

  The fixing member 40 is formed in a block shape, and the first rod 11, the second rod 12, and the permanent magnets 31 and 32 are provided on one side surface (the front side in FIG. 1 and the lower side in FIG. 2B). A recessed space for accommodating is recessed. That is, a concave space for accommodating the permanent magnets 31 and 32 is formed in a rectangular shape in front view at a substantially central portion of the fixing member 40, and the concave space for accommodating the permanent magnets 31 and 32 is formed in the vertical direction (the vertical direction in FIG. 1). ), A groove-like recess space that accommodates the first rod 11 and the second rod 12 extends in the left-right direction (left-right direction in FIG. 1).

  Between the concave spaces for accommodating the first rod 11 and the second rod 12, a regulating portion 41 having a rectangular shape in front view is projected at a position adjacent to the concave space for accommodating the permanent magnets 31 and 32. The thickness dimension (the vertical dimension in FIG. 1) of the restricting portion 41 is made larger than the thickness dimension (the vertical dimension in FIG. 1) of the permanent magnets 31 and 32.

  The upper and lower (upper and lower) side surfaces of the fixing member 40 are formed as inclined surfaces that are inclined along the press-fitting direction when the fixing member 40 is press-fitted into the holder member 50. Due to the inclination (gradient) of the upper and lower inclined surfaces, the fixing member 40 is formed in a shape that tapers as the distance from the axial center of the first rod 11 and the second rod 12 increases in the front view shown in FIG. .

  The holder member 50 includes a substantially rectangular parallelepiped base portion 51 and press-fit facing portions 52 and 53 that protrude from the base portion 51 and face each other at a predetermined interval. The fixing member 40 is held between the two.

  The mutually opposing surfaces of the press-fitting opposing portions 52 and 53 are formed as inclined surfaces that are inclined along the press-fitting direction when the fixing member 40 is press-fitted into the holder member 50. Due to the inclination (gradient) of these opposing surfaces, the facing interval becomes narrower toward the base portion 51. Note that a fastening hole 52 a is recessed in the upper side surface of the press-fitting facing portion 52 in one of the pair of holder members 50 (right side in FIG. 1).

  Here, the power generation element 10 has a resonance frequency (second frequency) of the pendulum motion (free vibration) higher than the resonance frequency (first frequency) of the pendulum motion (free vibration) in the excitation device 70 (high frequency). Frequency), and in the present embodiment, the second frequency is set to 150 Hz. In addition, it is preferable that the resonance frequency (second frequency) of free vibration in the power generation element 10 is set to about 100 Hz to 200 Hz.

  The vibration device 70 is a mass member 71 configured as a mass body (movable mass), a fixed member 72 fixed to the vibration source SV side, and interposed between the mass member 71 and the fixed member 72 and fixed. An elastic support member 73 that elastically supports the mass member 71 with respect to the member 72 so as to freely vibrate, and these members 71 to 73 are integrally formed from a steel material.

  The mass member 71 is formed in a rectangular parallelepiped shape, and is disposed to face the other holding member 60 of the power generation element 10 (on the left side in FIG. 1 and on the free end side capable of free vibration) with a predetermined interval. That is, the mass member 71 is disposed at a position where the lower surface (lower side surface in FIG. 1) can collide with the upper surface (upper side surface in FIG. 1) of the other holding member 60.

  The mass member 71 is disposed at a position protruding outward (on the opposite side to the elastic support member 73, left side in FIG. 1) from the end surface of the holding member 60 (the base portion 51 of the holder member 50). Thereby, since the mass member 71 can be made to collide with the most end part (left end of FIG. 1) of the holding member 60, the free vibration can be efficiently generated in the power generation element 10.

  The fixing member 72 is formed in a rectangular parallelepiped shape, and is fastened and fixed to one holding member 60 (the right side in FIG. 1, that is, the fixed end side fixed to the vibration source SV) of the power generation element 10 by a fastening bolt bt. That is, an insertion hole 72 a is formed through the fixing member 72, and the fastening bolt bt is inserted into the insertion hole 72 a of the fixing member 72 and fastened to the fastening hole 52 a of one holding member 60.

  Similar to the first rod 11 and the second rod 12, the elastic support member 73 is formed in a long plate shape having a rectangular section with a large width dimension relative to the thickness dimension, and has a side surface with a large area (that is, a long side in the section). Are arranged in parallel to the first rod 11 and the second rod 12. When the elastic support member 73 is bent and deformed, the mass member 71 is pendulum-moved (free vibration) with respect to the fixed member 72. That is, when the vibration device 70 is resonated by the input of vibration from the vibration source SV, the mass member 71 periodically collides with the other holding member 60 of the power generation element 10.

  Here, the vibration device 70 has a resonance frequency (first frequency) of the pendulum motion (free vibration) lower than the resonance frequency (second frequency) of the pendulum motion (free vibration) in the power generation element 10 (low frequency). Frequency), and in the present embodiment, the first frequency is set to 10 Hz. That is, the resonance frequency (first frequency) of the free vibration in the vibration generator 70 matches the vibration frequency of the vibration source SV.

  According to the power generation unit 1 configured as described above, the pair of permanent magnets 31 and 32 are sandwiched between the first rod 11 and the second rod 12 facing each other with different magnetic poles. A magnetic loop is formed by the second rod 12 and the pair of permanent magnets 31 and 32, and a bias magnetic field generated by the magnetomotive force of the permanent magnets 31 and 32 is applied to the first rod 11 and the second rod 12. Therefore, the first rod 11 and the second rod 12 are expanded or contracted by the pendulum motion (free vibration), so that the magnetic flux density is changed in a direction parallel to the axial direction (left and right direction in FIG. 1). As a result, a current is generated in the coil 20 wound around the first rod 11, and power generation is performed.

  In this case, the second frequency that is the resonance frequency of the pendulum motion (free vibration) in the power generation element 10 is matched with the vibration frequency of the vibration source SV (for example, the mass of the one holding member 60, the first rod 11 and the first rod 11). Power generation may be performed by resonating the power generation element 10 by vibration of the vibration source SV).

  However, this method cannot efficiently generate power. That is, the generated voltage V is determined by V = 2π · f · B · N · S (f: frequency, B: change amount of magnetic flux density, N: number of turns of coil, S: cross-sectional area of magnetostrictive rod), As much as possible, setting the frequency f to a large value (high frequency) and increasing the generated voltage is necessary for efficient power generation. The vibration source SV has a low frequency of about 3 Hz to 20 Hz, for example. Therefore, even if the power generation element 10 is made to resonate with the low-frequency vibration, the generated voltage is low and efficient power generation cannot be performed.

  On the other hand, according to the power generation unit 1, the first frequency (10 Hz in this embodiment), which is the resonance frequency of the pendulum motion (free vibration) in the vibration generator 70, is matched with the vibration frequency of the vibration source SV. Therefore, the vibration device 70 can be made to resonate and the mass member 71 can be periodically collided with the holding member 60 on the other (free end side) of the power generation element 10, thereby generating free vibration in the power generation element 10. The power generation by the power generation element 10 can be performed efficiently.

  That is, it is not necessary to match the resonance frequency (second frequency) of the pendulum motion (free vibration) in the power generation element 10 with the vibration (that is, low frequency vibration) of the vibration source SV, and high frequency (150 Hz in this embodiment). Therefore, power generation can be performed with the generation voltage of the power generation element 10 secured. As a result, power generation can be performed efficiently in the vibration source SV having a relatively low frequency of vibration.

  Further, if the resonance frequency (second frequency) of the power generation element 10 can be set to a high frequency, the mass of the holding member 60 on the other side (free end side, left side in FIG. 1) that functions as a mass body (movable mass) can be reduced. Thereby, since the volume of the part unrelated to power generation can be reduced, the power density (the power that can be extracted from per unit volume) can be increased accordingly.

  Similarly, if the resonance frequency (second frequency) of the power generation element 10 can be set to a high frequency, the spring constant of the power generation element 10 can be increased. Thereby, since the axial direction length of the 1st stick | rod 11 and the 2nd stick | rod 12 can be shortened, the size reduction of the electric power generation unit 1 can be achieved. Moreover, since the thickness dimension and width dimension of the 1st stick | rod 11 and the 2nd stick | rod 12 can be enlarged, magnetic flux can be made hard to leak. Furthermore, since the opposing space | interval of the 1st rod 11 and the 2nd rod 12 can be widened, the arrangement | positioning space of the coil 20 can be ensured and the winding number can be increased. As a result, the power generation efficiency can be improved.

  According to the power generation element 10 of the power generation unit 1, the coil 20 is wound only on the first rod 11, and there is no need to wind the coil 20 around the second rod 12. Can be planned. If it is not necessary to wind the coil 20 around the second rod 12, the coil 20 that is wound around the first rod 11 by using a space for winding the coil 20 around the second rod 12 originally. The number of turns can be increased. That is, this configuration also contributes to improvement of power generation efficiency.

  Here, in the structure of the power generation unit 1, the direction of the magnetic field formed along the axial direction (left and right direction in FIG. 1) of the first rod 11 and the axial direction (left and right direction of FIG. 1) of the second rod 12. The direction of the magnetic field formed in the opposite direction is the opposite direction. Therefore, when the first rod 11 and the second rod 12 are expanded or contracted during power generation, the changes in the magnetic flux density in the direction parallel to the axial direction are reversed and cancel each other. Therefore, the change in magnetic flux density is reduced, resulting in a decrease in power generation efficiency.

  In this case, according to the power generation unit 1, since the second rod 12 (that is, the magnetostrictive rod around which the coil is not wound) is made of a magnetostrictive material having a magnetostriction effect lower than that of the first rod 11, the first rod during power generation. When the 11 and the second rod 12 are expanded or contracted, the change in the magnetic flux density in the direction parallel to the axial direction of the second rod 12 can be reduced. Therefore, the change in the magnetic flux density in the direction parallel to the axial direction in the first rod 11 can be suppressed from being canceled by the change in the magnetic flux density in the direction parallel to the axial direction in the second rod 12. The change in magnetic flux density in the direction parallel to the axial direction of the necessary first rod 11 can be ensured, and the power generation efficiency can be improved.

  Further, the second rod 12 does not need to be made of a magnetostrictive material having a high magnetostrictive effect, and can be made of a general magnetic material (steel material in the present embodiment). The material cost of the second rod 12 can be reduced, and the product cost of the power generation unit 1 as a whole can be reduced accordingly.

  Next, the power generation unit 201 in the second embodiment will be described with reference to FIG. In the first embodiment, the case where the elastic support member 73 is formed as a leaf spring has been described. However, the elastic support member 273 in the second embodiment is formed as a coil spring. In addition, the same code | symbol is attached | subjected to the part same as 1st Embodiment mentioned above, and the description is abbreviate | omitted.

  FIG. 3 is a front view of the power generation unit 201 in the second embodiment. The power generating element 210 in the second embodiment is the same as the other configuration except that the configuration of one holding member 260 (holder member 250) is different from the holding member 60 (holder member 50) in the first embodiment. Since it is the same as the electric power generation element 10 in 1 embodiment, the description is abbreviate | omitted.

  As shown in FIG. 3, the power generation unit 201 in the second embodiment includes a power generation element 210 and a vibration device 270. One holding member 260 of the power generation element 210 includes a fixing member 40 attached to one end side in the axial direction of the first rod 11 and the second rod 12, and a holder member 250 into which the fixing member 40 is press-fitted. The holder member 250 is made of a nonmagnetic material (in this embodiment, an aluminum alloy).

  The holder member 250 has the base portion 251 and the press-fitting facing portion 252 extended upward (upper side in FIG. 3), so that the holder member 250 is more than the base portion 51 and the press-fitting facing portion 52 of the holder member 50 in the first embodiment. Further, the height dimension is increased, and an overhang portion 254 is formed to protrude from the side surface of the press-fitting facing portion 252.

  The vibration device 270 is interposed between the mass member 271 configured as a mass body (movable mass) and the mass member 271 and the overhanging portion 254 of the holder member 250, and is connected to the overhanging portion 254 with respect to the mass. And an elastic support member 273 that elastically supports the member 271 so as to freely vibrate.

  The mass member 271 is formed in a rectangular parallelepiped shape, and is disposed so as to face the other holding member 60 of the power generating element 210 (on the left side in FIG. 3, the free end side capable of free vibration) with a predetermined interval. That is, the mass member 271 is disposed at a position where the lower surface (lower side surface in FIG. 3) can collide with the upper surface (upper side surface in FIG. 3) of the other holding member 60.

  The elastic support member 273 is formed as a coil spring made of a steel material, and suspends the mass member 271 on the lower surface side of the overhang portion 254 of the holder member 250. When the elastic support member 273 is expanded and contracted, the mass member 271 is freely vibrated in the vertical direction (the vertical direction in FIG. 3) with respect to the protruding portion 254 of the holder member 250. That is, when the vibration device 270 is resonated by the input of vibration from the vibration source SV, the mass member 271 periodically collides with the other holding member 60 of the power generation element 210.

  As described above, the elastic support member 273 is formed as a coil spring, so that the coil spring is replaced according to the installation environment (vibration frequency of the vibration source SV) of the power generation unit 201 and the spring of the elastic support member 273 is replaced. Since the constant (that is, the resonance frequency (first frequency) of the vibration exciter 270) can be changed, adjustment according to the installation environment can be easily performed, and more efficient power generation becomes possible.

  In addition, since the resonant frequency (1st frequency and 2nd frequency) of the vibration exciting apparatus 270 and the electric power generation element 210 is set similarly to the case of 1st Embodiment, the description is abbreviate | omitted.

  According to the power generation unit 201 in the second embodiment, as with the power generation unit 1 in the first embodiment, the vibration frequency of the vibration source SV is set while the resonance frequency (second frequency) of the power generation element 210 is set to a high frequency. By causing the vibration device 270 to resonate and causing the mass member 271 to periodically collide with the holding member 60 on the other (free end side) of the power generation element 210, free vibration is generated in the power generation element 210, and Power generation can be performed efficiently.

  Here, in the power generation unit 1 according to the first embodiment, the vibration device 70 includes the mass member 71, the fixing member 72, and the elastic support member 73, but the vibration device of the power generation unit 201 according to the second embodiment. 270 includes only the mass member 271 and the elastic support member 273, and the fixing member is omitted.

  In other words, the overhang portion 254 corresponding to the “fixing member” of the vibrating device 270 is formed integrally with the holding member 260 (specifically, the holder member 250) of the power generation element 210. As a result, the number of parts can be reduced and the assembling process can be simplified as compared with the case where the fixing member of the vibration exciter 270 and the holding member 260 of the power generation element 210 are separated from each other. The product cost as a whole can be reduced.

  Next, the power generation unit 301 in the third embodiment will be described with reference to FIG. Although the case where the elastic support member 73 is formed as a leaf spring has been described in the first embodiment, the elastic support member 373 in the third embodiment is formed as a rubber-like elastic body. In addition, the same code | symbol is attached | subjected to the part same as 1st Embodiment mentioned above, and the description is abbreviate | omitted.

  FIG. 4 is a front view of the power generation unit 301 in the third embodiment. The power generating element 310 according to the third embodiment has the other configuration except that the configuration of one holding member 360 (holder member 350) is different from the holding member 60 (holder member 50) according to the first embodiment. Since it is the same as the electric power generation element 10 in 1 embodiment, the description is abbreviate | omitted.

  As shown in FIG. 4, the power generation unit 301 in the third embodiment includes a power generation element 310 and a vibration device 370. One holding member 360 of the power generation element 310 includes a fixing member 40 attached to one end side in the axial direction of the first rod 11 and the second rod 12, and a holder member 350 into which the fixing member 40 is press-fitted. The holder member 350 is made of a nonmagnetic material (in this embodiment, an aluminum alloy).

  The holder member 350 has a base portion 351 and a press-fitting facing portion 352 extending upward (upper side in FIG. 4) so that the holder member 350 is more than the base portion 51 and the press-fitting facing portion 52 of the holder member 50 in the first embodiment. Further, the height dimension is increased, and an overhang portion 354 is formed so as to overhang from the side surface of the press-fitting facing portion 352.

  The vibration device 370 is interposed between a mass member 371 configured as a mass body (movable mass) and the mass member 371 and the overhanging portion 354 of the holder member 350. And an elastic support member 373 that elastically supports the member 371 so as to freely vibrate.

  The mass member 371 is formed in a cubic shape, and is disposed to face the other holding member 60 of the power generation element 310 (on the left side in FIG. 4, the free end side capable of free vibration) with a predetermined interval. That is, the mass member 371 is disposed at a position where the lower surface (lower side surface in FIG. 4) can collide with the upper surface (upper side surface in FIG. 3) of the other holding member 60.

  The elastic support member 373 is formed as a rubber-like elastic body (vulcanized molded body) having a circular cross section, and supports the mass member 371 on the side end surface (left side surface in FIG. 4) of the overhang portion 254 of the holder member 250. As the elastic support member 373 is bent and deformed, the mass member 371 is subjected to pendulum vibration (free vibration) with respect to the protruding portion 354 of the holder member 350. That is, when the vibration device 370 is resonated by the input of vibration from the vibration source SV, the mass member 371 periodically collides with the other holding member 60 of the power generation element 310.

  The mass member 371 is disposed at a position protruding outward (on the opposite side to the elastic support member 373, left side in FIG. 4) from the end surface of the holding member 60 (base portion 51 of the holder member 50). Thereby, since the mass member 371 can collide with the outermost end part (left end in FIG. 4) of the holding member 60, free vibration can be efficiently generated in the power generation element 310.

  Here, the elastic support member 373 is formed as a rubber-like elastic body, so that the rubber hardness and the like are adjusted according to the installation environment (vibration frequency of the vibration source SV) of the power generation unit 301, and the elastic support member 373. The spring constant (that is, the resonance frequency (first frequency) of the vibration exciter 370) can be changed, so that adjustment according to the installation environment can be easily performed and more efficient power generation is possible.

  Note that the resonance frequencies (first frequency and second frequency) of the vibration generator 370 and the power generating element 310 are set in the same manner as in the first embodiment, and thus description thereof is omitted.

  According to the power generation unit 301 in the third embodiment, similarly to the power generation unit 1 in the first embodiment, the vibration frequency of the vibration source SV is set while the resonance frequency (second frequency) of the power generation element 310 is set to a high frequency. The vibration device 370 is caused to resonate, and the mass member 371 is periodically collided with the holding member 60 on the other (free end side) of the power generation element 310, thereby generating free vibration in the power generation element 310. Power generation can be performed efficiently.

  Further, according to the power generation unit 301, as in the case of the second embodiment, the overhanging portion 354 corresponding to the “fixing member” of the vibration generator 370 is provided with the holding member 360 (specifically, It is integrally formed with the holder member 350). As a result, the number of components can be reduced and the assembly process can be simplified, compared with the case where the fixing member 40 of the vibration exciting device 370 and the holding member 360 of the power generation element 310 are separated, and the power generation unit accordingly. 301 can reduce the product cost as a whole.

  As described above, the present invention has been described based on the embodiments, but the present invention is not limited to the above-described embodiments, and various improvements and modifications can be easily made without departing from the spirit of the present invention. It can be guessed.

  The numerical values given in the above embodiments are examples, and other numerical values can naturally be adopted.

  In each of the above-described embodiments, the case where the holding members 60, 260, and 360 are configured by two members, that is, the fixing member 40 and the holder members 50, 250, and 350 has been described. 40 and the holder members 50, 250, and 350 may be integrally formed. In this case, since the holding action of the first rod 11 and the like by press fitting cannot be obtained, the first rod 11 and the like are fixed to the holding members 60, 260, and 360 by adhesive fixing with an adhesive. .

  In each of the above-described embodiments, the case where the coil 20 is wound only on the first rod 11 has been described. However, the present invention is not necessarily limited thereto, and the coil 20 is provided on both the first rod 11 and the second rod 12. May be wound. In this case, the first rod 11 and the second rod 12 are made of the same magnetostrictive material (that is, the second rod 12 need not be made of a material having a lower magnetostriction effect than the first rod 11).

  In each of the above-described embodiments, the case where the power generation elements 10, 210, 310 are employed as the power generation elements constituting the power generation units 1, 201, 301 has been described. However, the present invention is not necessarily limited to this. A magnetostrictive rod and a coil wound around the magnetostrictive rod, and one end in the axial direction of the magnetostrictive rod is a fixed end fixed to the vibration source side, and the other end in the axial direction is a free end capable of free vibration If the magnetostrictive rod is expanded or contracted in the axial direction to generate power by the inverse magnetostrictive effect, other power generating elements may be employed. As another power generation element, for example, a power generation element 901 shown in FIG. 5 is exemplified.

  In the first embodiment, the case where the mass member 71, the fixing member 72, and the elastic support member 73 of the vibration device 70 are integrally formed has been described. However, the present invention is not necessarily limited thereto, and these mass members 71 are not necessarily limited thereto. The fixing member 72 and the elastic support member 73 may be formed separately. Accordingly, the mass member 71 and the elastic support member 73 can be changed according to the installation environment of the power generation unit 1 (vibration frequency of the vibration source SV), and the resonance frequency (first frequency) of the vibration excitation device 70 can be changed. Therefore, adjustment according to the installation environment can be easily performed, and more efficient power generation becomes possible.

  In each of the above-described embodiments, the case where the mass members 71, 271 and 371 directly collide with the holding member 60 (holder member 50) has been described. However, the present invention is not limited to this, and a rubber sheet or the like is not necessarily provided between them. A cushioning material may be interposed. Thereby, it is possible to prevent abnormal noise and improve durability.

  In each of the above-described embodiments, the case where the vibration devices 70, 270, and 370 include one mass member 71, 271 and 371 has been described. However, the present invention is not necessarily limited thereto, and the vibration devices 70, 270, and 370 are not necessarily limited thereto. May be provided with a plurality of mass members 71, 271, 371. In this case, the mass members 71, 271, 371 are elastically supported by a plurality of elastic support members 73, 273, 373 so that the mass members 71, 271, 371 can freely vibrate individually. 373 is set to a different spring constant (instead of or in addition to this, the mass of each mass member 71, 271 and 371 is set differently). As a result, even if the vibration frequency of the vibration source SV changes, any one of the mass members 71 271 371 among the plurality of mass members 71 271 371 can be held by the holding member 60 of the power generating elements 10, 210 310. And free vibration can be generated in the power generation elements 10, 210, 310. Therefore, the frequency band in which the power generation by the power generation elements 10, 210, 310 can be expanded using the resonance of the vibration devices 70, 270, 370.

  In the first embodiment, the case where the power generation element 10 and the vibration generator 70 are connected (fastened and fixed) to configure the power generation unit 1 has been described. However, the present invention is not necessarily limited thereto, and the power generation unit is not necessarily limited thereto. 1, the power generation element 10 and the vibration device 70 may be disconnected. That is, one holding member 60 of the power generation element 10 and the fixing member 72 of the vibration device 70 may be individually fixed to the vibration source SV.

  In each of the above embodiments, the case where the lower surface of the press-fitting facing portion 53 of the holder member 50, 250, 350 is fixed to the vibration source SV has been described, but the present invention is not necessarily limited thereto, and the holder member 50, 250, Any part of 350 may be fixed to the vibration source SV. Also, the fixing method can be appropriately selected. For example, adhesion fixation, welding fixation, fastening fixation, etc. are illustrated.

1, 201, 301 Power generation unit 10, 210, 310 Power generation element 11 First rod (magnetostrictive rod)
12 Second rod (magnetostrictive rod)
20 Coils 31, 32 Permanent magnet 40 Fixed member (part of holding member)
50, 250, 350 Holder member (part of the holding member)
60, 260, 360 Holding members 70, 270, 370 Excitation devices 71, 271, 371 Mass members 72 Fixing members 73, 273, 373 Elastic support members SV Vibration source

Claims (4)

A power generation unit that includes a power generation element and a vibration generator, and generates power using vibrations of a mounted vibration source,
The power generating element is:
A magnetostrictive rod composed of a magnetostrictive material;
A coil wound around the magnetostrictive rod,
One end side in the axial direction of the magnetostrictive rod is a fixed end fixed to the vibration source side and the other end side in the axial direction is a free end capable of free vibration, and the magnetostrictive rod is expanded or contracted in the axial direction. Power is generated by the inverse magnetostrictive effect,
The vibration exciter is
A mass member that is configured as a mass body and is disposed opposite to the other end side of the magnetostrictive rod of the power generating element with a predetermined interval therebetween;
A fixing member fixed to the vibration source side;
An elastic support member interposed between the fixing member and the mass member and elastically supporting the mass member so as to freely vibrate with respect to the fixing member;
A first frequency, which is a resonance frequency of the vibration device, is set lower than a second frequency, which is a resonance frequency of the power generation element, and vibration of the first frequency is input from the vibration source, and the vibration device is When resonating, the mass member periodically collides with the other end of the magnetostrictive rod of the power generating element. The magnetostrictive rod includes a first rod and a second rod which are made of a magnetostrictive material and have one axial end as a fixed end fixed to the vibration source side and the other axial end as a free end capable of free vibration. ,
The coil is wound around at least one of the first rod or the second rod;
The power generating element is:
A pair of permanent magnets that are sandwiched between the opposing ends of the first rod and the second rod on the one end side and the other end side in the axial direction of the first rod and the second rod, and arranged with different magnetic poles;
A pair of holding members that are attached to one end side and the other end side in the axial direction of the first bar and the second bar, respectively, and hold the state in which the permanent magnet is sandwiched between the first bar and the second bar. The power generation unit according to claim 1, further comprising:   The power generation unit according to claim 2, wherein the second rod is made of a magnetostrictive material having a lower magnetostrictive effect than the first rod, and the coil is wound only on the first rod.   The power generation unit according to claim 2 or 3, wherein a fixing member of the vibration exciter is formed integrally with a holding member of the power generation element.

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