JP2014007798A - Oscillation power generator - Google Patents

Abstract

A vibration power generator having higher power generation efficiency is provided.
A vibration power generation element including a cantilever portion, a weight portion provided on a free end of the cantilever portion, and a piezoelectric conversion portion that generates electric power when the cantilever portion is swung can pass a fluid. A housing that constitutes at least part of the possible through hole 30a and accommodates the cantilever part 1b in the through hole 30a along the direction connecting the free end 1ba side and the fixed end 1bb side of the cantilever part 1b in the direction of the through hole 30a. The weight portion 1c has a curved surface at the tip of the weight portion 1c protruding from the cantilever portion 1b in a direction connecting at least the free end 1ba side and the fixed end 1bb side of the cantilever portion 1b. 1ca is configured.
[Selection] Figure 1

Description

  The present invention relates to a vibration power generation apparatus using a vibration power generation element that converts vibration energy into electric energy.

  In recent years, a vibration power generation apparatus using a vibration power generation element that converts vibration energy into electric energy has attracted attention in fields such as energy harvesting.

  As this type of vibration power generation device, a piezoelectric hydroelectric power generation device 101 in which a power generation unit 104 including a piezoelectric element 106 that is fixed to a vibration plate 105 and converts vibration energy into electric energy, shown in FIG. Is known (for example, Patent Document 1).

  The piezoelectric hydroelectric power generation device 101 of Patent Document 1 rectifies the power generated by the power generation unit 104 by a rectification unit 108 configured by a diode 109, and supplies the rectified power to a power storage unit 110 configured by a secondary battery 111. Accumulate electricity. Note that the power generation unit 104 serving as a vibration power generation element includes vibration generation means 107 that generates vibration on the diaphragm 105 when the water flow 103 is received.

  As a vibration power generation element of the vibration power generation apparatus, a power generation device including a cantilever forming substrate 220 having a support portion 221 and a cantilever portion 222 and a piezoelectric conversion portion 224 formed on the cantilever portion 222 shown in FIG. (For example, Patent Document 2).

  In the power generation device shown in Patent Document 2, the piezoelectric conversion unit 224 includes a lower electrode 224a, a piezoelectric layer 224b, and an upper electrode 224c. In addition, the power generation device is provided with a weight portion 223 for increasing the amount of displacement of the cantilever portion 222 at the tip portion of the cantilever portion 222 in the cantilever forming substrate 220. In the power generation device, the piezoelectric conversion unit 224 generates an AC voltage in response to the swing of the cantilever unit 222.

  In the piezoelectric converter 224, the lower electrode 224a is electrically connected to the lower electrode pad 227a through the connection wiring 226a. In the piezoelectric conversion unit 224, the upper electrode 224c is electrically connected to the upper electrode pad 227c through the connection wiring 226c. The power generation device includes an insulating layer 225 that prevents a short circuit between the upper electrode 224c and the lower electrode 224a. Furthermore, the power generation device includes insulating films 229a and 229b on one surface side and the other surface side of the cantilever forming substrate 220, respectively.

  The power generation device can output the electric power generated by the piezoelectric conversion unit 224 from the lower electrode pad 227a and the upper electrode pad 227c by swinging the cantilever unit 222 by vibration.

JP 2001-275370 A JP 2011-91319 A

  By the way, the vibration power generator is required to have a higher output, and the above-described configuration of Patent Document 1 is not sufficient, and further improvement is required. In the vibration power generation apparatus, for example, a vibration power generation element including a weight portion 223 capable of increasing the displacement amount of the cantilever portion 222 is applied to the power generation portion 104 of Patent Literature 1 as in the power generation device of Patent Literature 2. It can be considered.

  However, in the vibration power generation apparatus in which the vibration power generation element including the weight portion 223 of the power generation device of Patent Document 2 is simply applied to the power generation section 104 of Patent Document 1, the power generation efficiency is further increased by using a fluid. Is difficult.

  The present invention has been made in view of the above-described reasons, and an object thereof is to provide a vibration power generator having higher power generation efficiency.

  The vibration power generation device of the present invention includes a vibration power generation element including a cantilever portion, a weight portion provided on a free end side of the cantilever portion, and a piezoelectric conversion portion that generates power by receiving stress generated by the swinging of the cantilever portion, and a fluid The cantilever portion of the vibration power generation element is configured to form at least a part of a through-hole through which the free end side and the fixed end side of the cantilever portion are connected in the direction of the through-hole. A vibration power generation apparatus having a housing portion that is housed in the through hole, wherein the weight portion projects from the cantilever portion in a direction connecting at least the free end side and the fixed end side of the cantilever portion. The tip of the weight portion is a curved surface.

  In this vibration power generation device, the housing portion has a supply port to which the fluid is supplied, a supply portion provided with a supply pipe communicating with the free end side of the cantilever portion in the through hole, and the fluid is discharged. And a discharge portion provided with a discharge pipe communicating with the fixed end side of the cantilever portion in the through hole.

  In this vibration power generation device, the housing portion has an inflow amount that increases the inflow amount of the fluid on the one surface side compared to the other surface side opposite to the one surface side of the cantilever portion provided with the weight portion. It is preferable that the control unit is provided in the supply unit.

  In the vibration power generator, the inflow amount control unit preferably has a tapered shape that reduces the opening area of the supply pipe from the supply port side toward the discharge port side.

  In this vibration power generation device, the housing portion may include a tapered outflow amount control unit that increases an opening area of the discharge pipe from the supply port side toward the discharge port side. preferable.

  In this vibration power generation device, the vibration power generation element and the housing portion are such that the size of the gap between the cantilever portion and the inner wall of the through hole is such that the fixed end side and the free end side of the cantilever portion are It is preferable that they are different.

  In the vibration power generation device, it is preferable that the vibration power generation element has different sizes of the gap between the fixed end side and the free end side of the cantilever part due to the bending of the cantilever part.

  In this vibration power generation device, it is preferable that the vibration power generation element includes a stress generating film that generates a stress that causes the bending in the cantilever portion.

  In this vibration power generation device, it is preferable that the vibration power generation element includes the weight portion on the upper side in the vertical direction of the cantilever portion.

  In the vibration power generation device of the present invention, since the tip of the weight portion protruding from the cantilever portion forms a curved surface, there is an effect that the power generation efficiency can be further increased.

1 is a schematic cross-sectional view of a vibration power generator according to Embodiment 1. FIG. It is a partial bottom view of the principal part in the vibration electric power generating apparatus of Embodiment 1. It is process drawing explaining the manufacturing method of the principal part in the vibration electric power generating apparatus of Embodiment 1. It is process drawing explaining the manufacturing method of the principal part in the vibration electric power generating apparatus of Embodiment 1. It is process drawing explaining the manufacturing method of the principal part in the vibration electric power generating apparatus of Embodiment 1. It is process drawing explaining the manufacturing method of the principal part in the vibration electric power generating apparatus of Embodiment 1. The vibration electric power generating apparatus of Embodiment 2 is shown, (a) is a schematic sectional view, (b) is a partial plan view. The other principal part of the vibration electric power generating apparatus of Embodiment 2 is shown, (a) is a top view, (b) is XX sectional drawing of (a). The other principal part of the vibration electric power generating apparatus of Embodiment 2 is shown, (a) is a top view, (b) is XX sectional drawing of (a). (A) is another top view of the vibration electric power generating apparatus of Embodiment 2, (b) is XX sectional drawing of (a). The vibration electric power generating apparatus of Embodiment 3 is shown, (a) is a schematic sectional drawing, (b) is a partial top view. The another vibration electric power generating apparatus of Embodiment 3 is shown, (a) is a schematic sectional drawing, (b) is a partial top view. It is a schematic sectional drawing which shows the other vibration electric power generating apparatus of Embodiment 3. FIG. 10 is a schematic cross-sectional view showing still another vibration power generator of Embodiment 3. It is a schematic sectional drawing which shows the vibration electric power generating apparatus of Embodiment 4. It is a bottom view of the principal part of the vibration electric power generating apparatus of Embodiment 4. It is a schematic sectional drawing of another principal part of the vibration electric power generating apparatus of Embodiment 4. It is a schematic sectional drawing of the other principal part of the vibration electric power generating apparatus of Embodiment 4. The vibration electric power generating apparatus of Embodiment 5 is shown, (a) is a schematic sectional drawing, (b) is a partial top view. 10 is a schematic cross-sectional view showing another vibration power generator of Embodiment 5. FIG. It is a block diagram which shows the conventional piezoelectric hydroelectric generator. A conventional electric power generation device is shown, (a) is a schematic plan view, (b) is an A-A 'schematic sectional view of (a).

(Embodiment 1)
Hereinafter, the vibration power generation apparatus 30 of the present embodiment will be described with reference to FIGS. 1 and 6.

  As shown in FIG. 1, the vibration power generation apparatus 30 of the present embodiment is a piezoelectric device that generates electric power by receiving stress generated by swinging of the cantilever portion 1b and the weight portion 1c provided on the free end 1ba side of the cantilever portion 1b and the cantilever portion 1b. The vibration power generation element 10 including the conversion unit 3 is included. The vibration power generator 30 has a housing part 20 that constitutes at least a part of a through hole 30a through which a fluid (not shown) can pass. The housing unit 20 of the vibration power generator 30 generates vibration power along the direction connecting the free end 1ba side of the cantilever part 1b and the fixed end 1bb side that fixes the cantilever part 1b to the support part 1a side in the direction of the through hole 30a. The cantilever part 1b in the element 10 is accommodated in the through hole 30a. In the vibration power generation apparatus 30, the tip of the weight portion 1c protruding from the cantilever portion 1b is curved 1ca in the direction in which the weight portion 1c of the vibration power generation element 10 connects at least the free end 1ba side and the fixed end 1bb side of the cantilever portion 1b. Is configured.

  Thereby, the vibration power generation apparatus 30 of this embodiment makes it easy to generate self-excited vibration due to the flow of the fluid as compared with a vibration power generation element in which the tip of the weight portion 1c does not form the curved surface 1ca. The power generation efficiency can be further increased. Examples of the fluid include air, a gas such as an appropriate gas, and a liquid such as water.

  In the vibration power generation apparatus 30 of the present embodiment, the housing part 20 has a supply port 21aa to which the fluid is supplied and a supply part provided with a supply pipe 21a communicating with the free end 1ba side of the cantilever part 1b in the through hole 30a. 21 is provided. The housing portion 20 includes a discharge portion 22 having a discharge port 22aa for discharging the fluid and provided with a discharge pipe 22a communicating with the fixed end 1bb side of the cantilever portion 1b in the through hole 30a. In the vibration power generator 30 of the present embodiment, the fluid is efficiently supplied to the curved surface 1ca side of the weight portion 1c by supplying the fluid from the supply pipe 21a on the free end 1ba side of the cantilever portion 1b provided with the weight portion 1c. It is possible to flow. In the vibration power generation device 30 of the present embodiment, the upper side of the sheet of FIG. 1 is the vertical upward direction, and the vibration power generation element 10 is arranged so that the weight portion 1c is provided on the upper side in the vertical direction of the cantilever portion 1b. doing.

  First, the vibration power generation element 10 used in the vibration power generation apparatus 30 of the present embodiment will be described with reference to FIGS. 1 and 2. A method for manufacturing the vibration power generation element 10 will be described with reference to FIGS. The vibration power generation element 10 used in the vibration power generation apparatus 30 of the present embodiment is a thin film type piezoelectric element manufactured using a manufacturing technology of MEMS (Micro Electro Mechanical Systems). Hereinafter, each configuration of the vibration power generation element 10 will be described.

  The vibration power generation element 10 is an SOI (Silicon) having a structure in which a buried oxide film 12c made of a silicon oxide film is sandwiched between a single crystal silicon substrate 12b and a single crystal silicon layer (active layer) 12d as a base substrate 1. on Insulator) board. As the SOI substrate to be the base substrate 1, a silicon layer 12d having a (100) surface is used.

  In addition, since the vibration power generation element 10 uses an SOI substrate as the base substrate 1, the buried oxide film 12c of the SOI substrate is used as an etching stopper layer when forming the cantilever portion 1b in the manufacturing process described later. Can do. As a result, the vibration power generation element 10 can improve the thickness of the cantilever portion 1b, improve the reliability, and reduce the cost. The base substrate 1 is not limited to the SOI substrate, and may be a single crystal silicon substrate, another crystal silicon substrate, a magnesium oxide (MgO) substrate, a metal substrate, a glass substrate, a polymer substrate, or the like. In the base substrate 1, an insulating film 12e made of a silicon oxide film is formed on the other surface 1bd side opposite to the one surface 1bc of the cantilever portion 1b provided with the weight portion 1c.

  The vibration power generation element 10 includes a first pad electrode 8a electrically connected to the first electrode 3a1 via the first connection wiring 7a on the other surface 1bd side in the support portion 1a (see FIG. 2). . In addition, the vibration power generation element 10 includes a second pad electrode 8b electrically connected to the second electrode 3a2 via the second connection wiring 7b on the other surface 1bd side.

  The base substrate 1 in the vibration power generation element 10 of the present embodiment is supported by a support portion 1a having a protruding portion 1aa inclined so that the tip end portion 1ab spreads outward and one end serving as a fixed end 1bb in plan view. The cantilever part 1b supported by the part 1a so that rocking is possible, and the weight part 1c by the side of the free end 1ba of the cantilever part 1b are provided. The support portion 1a has a pair of protrusions 1aa and is C-shaped in a plan view. In addition, the weight part 1c is made to protrude from the cantilever part 1b, and has the structure provided with the curved surface 1ca on the surface. The weight portion 1c can be formed in various shapes such as a hemispherical shape and a semi-elliptical spherical shape as long as the surface has a curved surface 1ca. Further, the weight portion 1c is not limited to the case where only one cantilever portion 1b is provided, and a plurality of weight portions 1c may be provided on the cantilever portion 1b.

  The piezoelectric conversion unit 3 functions as a power generation unit. The piezoelectric conversion unit 3 is designed so that the planar size of the piezoelectric layer 3a3 is smaller than that of the first electrode 3a1. In addition, the piezoelectric conversion unit 3 is designed such that the planar size of the second electrode 3a2 in contact with the piezoelectric layer 3a3 is smaller than that of the piezoelectric layer 3a3. The piezoelectric conversion unit 3 has the piezoelectric layer 3a3 positioned inside the outer peripheral edge of the first electrode 3a1 and the second electrode 3a2 contacting the piezoelectric layer 3a3 inside the outer peripheral edge of the piezoelectric layer 3a3 in plan view. doing. In addition, in the piezoelectric conversion portion 3, an insulating layer 3a4 that prevents a short circuit between the first electrode 3a1 side and the second electrode 3a2 side is formed so as to cover the respective peripheral portions of the first electrode 3a1 and the piezoelectric layer 3a3. . The insulating layer 3a4 defines an area where the piezoelectric layer 3a3 and the second electrode 3a2 are in contact with each other in plan view. That is, the planar view shape of the insulating layer 3a4 is a frame shape along the peripheral portion of the piezoelectric layer 3a3. Thereby, the insulating layer 3a4 can prevent a short circuit between the second connection wiring 7b electrically connected to the second electrode 3a2 and the first electrode 3a1.

  The insulating layer 3a4 is formed of a silicon oxide film. However, the insulating layer 3a4 is not limited to a silicon oxide film, and may be formed of a silicon nitride film, or may have a multilayer film structure as well as a single layer film. The insulating layer 3a4 may be formed of an electrically insulating resin. In the base substrate 1, the piezoelectric conversion unit 3 and the base substrate 1 are electrically insulated by an insulating film 12e.

  The piezoelectric conversion unit 3 generates power by receiving stress generated by the swinging of the cantilever unit 1b. In the piezoelectric conversion unit 3, an electric charge bias due to stress occurs in the piezoelectric layer 3 a 3. Therefore, the piezoelectric conversion unit 3 tends to increase the power generation output as the strain of the cantilever unit 1b increases.

In the vibration power generation apparatus 30 of the present embodiment, the piezoelectric conversion unit 3 uses PZT (Pb (Zr, Ti) O ₃ ) as the material of the piezoelectric layer 3a3. The piezoelectric layer 3a3 is not limited to PZT as a piezoelectric material. For example, PZT-PMN (: Pb (Mn, Nb) O ₃ ), PLZT ((Pb, La) (Zr, Ti) O ₃ ) or SBT is used. (SrBi ₂ Ta ₂ O ₉ ) or the like may be used. The piezoelectric material may be AlN, ZnO, KNN (K _0.5 Na _0.5 NbO ₃ ), KN (KNbO ₃ ), NN (NaNbO ₃ ), or the like.

  Here, in the vibration power generation element 10, the first electrode 3a1 is formed of a Pt film. The second electrode 3a2 is composed of a laminated film of a Ti film and an Au film. The first electrode 3a1 and the second electrode 3a2 of the vibration power generation element 10 are not particularly limited to these materials and layer structures, and each of the first electrode 3a1 and the second electrode 3a2 may have a single layer structure or a multilayer structure. It is good. As the electrode material of the first electrode 3a1, for example, Au, Al, Ir, In, or the like may be adopted. As the material of the second electrode 3a2, for example, Mo, Al, Pt, or the like may be adopted. .

  In the vibration power generation element 10, the piezoelectric layer 3 a 3 is located inside the outer peripheral edge of the first electrode 3 a 1 in plan view. Therefore, the vibration power generation element 10 can reduce the level difference of the portion serving as the base of the second connection wiring 7b as compared with the case where the first electrode 3a1 and the piezoelectric layer 3a3 have substantially the same planar size. As a result, the vibration power generation element 10 can also increase the reliability by reducing the possibility that the second connection wiring 7b of the piezoelectric conversion unit 3 is broken as the cantilever portion 1b swings.

  Further, in the vibration power generation element 10, an insulating layer 3a4 that prevents a short circuit between the first electrode 3a1 and the second electrode 3a2 may be extended to the support portion 1a. The vibration power generation element 10 forms all the portions of the second connection wiring 7b between the second electrode 3a2 and the second pad electrode 8b electrically connected to the second electrode 3a2 on the insulating layer 3a4. The two-pad electrode 8b may be formed on a flat portion of the insulating layer 3a4 (not shown). As a result, the vibration power generation element 10 can reduce the level difference of the portion serving as the base of the second connection wiring 7b, and the second electrode 3a2 and the second pad electrode 8b can be electrically connected while increasing the thickness of the piezoelectric layer 3a3. The possibility of disconnection of the second connection wiring 7b to be connected can be further reduced.

  The vibration power generator 30 of this embodiment can output the electric power generated by the piezoelectric conversion unit 3 to the outside via the first pad electrode 8a and the second pad electrode 8b.

  Hereinafter, a method for manufacturing the vibration power generation element 10 used in the vibration power generation apparatus 30 of the present embodiment will be described with reference to FIGS. 3 to 6. 3 to 6, a bottom view of the vibration power generation element 10 is illustrated on the left side, and a schematic cross-sectional view of a main part of the vibration power generation element 10 is illustrated on the right side.

  First, the method of manufacturing the vibration power generation element 10 is such that the insulating films 12e and 12a made of silicon oxide films are formed on the one surface side and the other surface side of the element forming substrate 11 made of the above-described SOI substrate, which becomes the base substrate 1, respectively. (See FIG. 3A). The element formation substrate 11 made of an SOI substrate has a structure in which a buried oxide film 12c made of a silicon oxide film is sandwiched between a single crystal silicon substrate 12b and a single crystal silicon layer 12d.

  Thereafter, in the method for manufacturing the vibration power generation element 10, the first metal film composed of the Pt layer that is the basis of the first electrode 3a1, the first connection wiring 7a, and the first pad electrode 8a is formed on the entire surface of the element forming substrate 11. 24 is formed by, for example, sputtering or CVD. The first metal film 24 is not limited to the Pt film, and may be an Al film or an Al—Si film, for example. In addition to the Au film, the first metal film 24 may have a structure in which a Ti film is interposed as an adhesion film for improving adhesion between the Au film and the insulating film 12e. Here, the material of the adhesion film (not shown) is not limited to Ti, and for example, Cr, Nb, Zr, TiN, TaN, or the like may be used. In the method for manufacturing the vibration power generation element 10, after the first metal film 24 is formed, a piezoelectric film (for example, a PZT film) 25 serving as a basis of the piezoelectric layer 3a3 is formed on the entire surface on one surface side of the element forming substrate 11, for example, , Sputtering method, CVD method, sol-gel method, transfer method or the like (see FIG. 3B).

Next, in the manufacturing method of the vibration power generation element 10, the piezoelectric film 3a3 formed of a part of the piezoelectric film 25 is formed by patterning the piezoelectric film 25 into a predetermined shape using a photolithography technique and an etching technique ( (Refer FIG.3 (c)). In the vibration power generation element 10, the piezoelectric layer 3a3 is formed on the first electrode 3a1. However, the piezoelectric layer 3a3 is formed between the piezoelectric layer 3a3 and the first electrode 3a1, and the base layer when the piezoelectric layer 3a3 is formed. The crystallinity of the piezoelectric layer 3a3 may be improved by interposing a seed layer. Examples of the material for the seed layer include PLT ((Pb, La) TiO ₃ ), PTO (PbTiO ₃ ), SRO (SrRuO ₃ ), and the like, which are one type of conductive oxide materials.

  In addition, the step of patterning the piezoelectric film 25 can be omitted by forming the piezoelectric layer 3a3 having a predetermined shape by a transfer method. In the transfer method of the piezoelectric layer 3a3, for example, a piezoelectric film made of a ferroelectric thin film is formed in advance on one surface of a piezoelectric film forming substrate (not shown) using a sputtering method, a CVD method, a sol-gel method, or the like. deep. Next, in the state where the piezoelectric film of the piezoelectric film forming substrate and the first metal film 24 serving as the basis of the first electrode 3a1 described above are disposed opposite to the element forming substrate 11, the light transmitting piezoelectric film is formed. Laser light is irradiated from the other surface side of the substrate for use. The laser light is irradiated so as to be absorbed at the interface between the piezoelectric film forming substrate and the piezoelectric film. Thereby, a part of the piezoelectric film is peeled off from the piezoelectric film forming substrate. The peeled piezoelectric film can be transferred to the first metal film 24 side of the element forming substrate 11 to form the piezoelectric layer 3a3. By controlling the region irradiated with the laser beam, the piezoelectric film can be transferred onto the first metal film 24 to be the first electrode 3a1 later in a plan view in a shape smaller than the outer shape of the first electrode 3a1.

The substrate for forming the piezoelectric film is preferably a substrate having a smaller lattice constant difference from the piezoelectric film serving as the basis of the piezoelectric layer 3a3 than the element forming substrate 11, and having good lattice matching. For example, when PZT is used as the material of the piezoelectric film, a single crystal MgO substrate, a single crystal STO (SrTiO ₃ ) substrate, or the like can be used as the piezoelectric film forming substrate. The laser beam for transferring a part of the piezoelectric film from the piezoelectric film forming substrate can be irradiated from, for example, a KrF excimer laser. Furthermore, a seed layer such as PLT, PTO, or SRO for controlling the crystal orientation of the piezoelectric film may be provided between the piezoelectric film forming substrate and the piezoelectric film. The seed layer can also be used as a sacrificial layer that is removed by absorbing laser light during the transfer of the piezoelectric film when part of the piezoelectric film is peeled off. When unnecessary fragments of the piezoelectric film forming substrate adhere to the element forming substrate 11 side as the piezoelectric film is transferred, it can be appropriately removed using an etching solution.

  By using such a transfer method in which the separately formed piezoelectric film is transferred to form the piezoelectric layer 3a3, the manufacturing time of the vibration power generation element 10 can be shortened. That is, compared with the method of manufacturing the vibration power generation element 10 by forming the piezoelectric layer 3a3 after the formation of the first metal film 24 described above, the formation process of the first electrode 3a1 is a time-consuming process for forming the piezoelectric film. It can be performed separately from the process.

  In the method of manufacturing the vibration power generation element 10, after forming the piezoelectric layer 3 a 3 illustrated in FIG. 3C, the first metal film 24 is patterned into a predetermined shape using a photolithography technique and an etching technique. Thus, the first electrode 3a1, the first connection wiring 7a, and the first pad electrode 8a made of a part of the first metal film 24 are formed (see FIG. 4A). The first electrode 3a1, the first connection wiring 7a, and the first pad electrode 8a are formed simultaneously. Here, the first electrode 3a1, the first connection wiring 7a, and the first pad electrode 8a are not only formed simultaneously by patterning the first metal film 24, but only the first electrode 3a1 is formed. May be.

  In this case, after forming the first electrode 3a1, the first connection wiring 7a and the first pad electrode 8a may be separately formed. Further, the step of forming the first connection wiring 7a and the step of forming the first pad electrode 8a may be provided separately. In the etching of the first metal film 24, for example, a reactive ion etching (RIE) method or an ion milling method can be appropriately employed.

  In the method of manufacturing the vibration power generation element 10, after the first electrode 3a1, the first connection wiring 7a, and the first pad electrode 8a are formed, the insulating layer 3a4 is formed on the one surface side of the element formation substrate 11 (FIG. 4B). See). In the step of forming the insulating layer 3a4, a resist is applied to one surface side of the element formation substrate 11 on which the piezoelectric layer 3a3 is formed, and then the resist is patterned by a photolithography technique. Subsequently, the element forming substrate 11 is formed by using a lift-off method in which an insulating film serving as a base of the insulating layer 3a4 is formed on the entire surface on one surface side of the element forming substrate 11 by a CVD method or the like, and then the resist is peeled off. An insulating layer 3a4 is formed. The step of forming the insulating layer 3a4 is not limited to the method of forming the insulating layer 3a4 using the lift-off method, and the insulating layer 3a4 may be formed by patterning using a photolithography technique and an etching technique. On the one surface side of the element formation substrate 11, an opening 3a4a having a rectangular shape in plan view is formed by forming the insulating layer 3a4.

  Next, in the method for manufacturing the vibration power generation element 10, in order to form the second electrode 3a2, a resist is applied to one surface side of the element formation substrate 11 on which the insulating layer 3a4 is formed, and then the resist is patterned by a photolithography technique. To do. Subsequently, in the element formation substrate 11, a second electrode 3a2 is formed by vapor-depositing a metal film serving as a basis of the second electrode 3a2 and performing a lift-off method for removing the resist. In the method for manufacturing the vibration power generation element 10 of the present embodiment, the second connection wiring 7b and the second pad electrode 8b are formed together with the second electrode 3a2 (see FIG. 4C). The second electrode 3a2 is formed using a thin film formation technique such as an electron beam (EB) vapor deposition method, a sputtering method, or a CVD method, a photolithography technique, and an etching technique, whereby the second connection wiring 7b and the second electrode 3a2. You may form simultaneously with the pad electrode 8b. Further, in the method for manufacturing the vibration power generation element 10, the second connection wiring 7b and the second pad electrode 8b are formed together with the second electrode 3a2, but not limited thereto, the second electrode 3a2 and the second connection are formed. The wiring 7b and the second pad electrode 8b may be performed separately. The second connection wiring 7b may be formed separately from the second pad electrode 8b.

  Subsequently, the manufacturing method of the vibration power generation element 10 uses a photolithographic technique and an etching technique using buffered hydrofluoric acid (BHF), and supports the support portion 1a, the cantilever portion 1b, and the weight portion from one side of the element formation substrate 11. The insulating film 12e other than the portion to be 1c is removed. As a result, the silicon layer 12d of the element formation substrate 11 is exposed (see FIG. 5A).

  Next, in the method for manufacturing the vibration power generation element 10, the silicon layer 12d at a portion where the insulating film 12e on one surface side of the element formation substrate 11 is removed is removed by etching using the RIE method. As a result, the buried oxide film 12c is exposed on the element formation substrate 11 (see FIG. 5B).

  Subsequently, the manufacturing method of the vibration power generation element 10 uses the photolithography technique and the etching technique using BHF or the like, and the parts that become the support part 1a, the cantilever part 1b, and the weight part 1c from the other surface side of the element formation substrate 11 The other insulating film 12a is removed. Thereby, in the element formation substrate 11, a part of the insulating film 12a is removed, and the single crystal silicon substrate 12b is exposed (see FIG. 5C).

  Subsequently, in the method for manufacturing the vibration power generation element 10, after removing a part of the insulating film 12a, the portion where the insulating film 12a is removed from the other surface side of the element forming substrate 11 is subjected to a buried oxide film by Deep-RIE method. The element formation substrate 11 is etched to a predetermined depth reaching 12c. Thereby, in the element formation substrate 11, the buried oxide film 12c on the other surface side of the element formation substrate 11 is exposed (see FIG. 6A).

  Next, in the manufacturing method of the vibration power generation element 10, an unnecessary portion of the buried oxide film 12c is removed by etching by the RIE method, and the cantilever portion 1b is configured to be swingable from the support portion 1a (see FIG. 6B). ).

  Subsequently, in the method for manufacturing the vibration power generation element 10, the insulating film 12 a at a portion constituting the weight portion 1 c is removed. In the method for manufacturing the vibration power generation element 10, an etching mask is formed in advance on the other surface side of the element forming substrate 11 except for the edge portion of the portion constituting the weight portion 1 c to be etched. In the method for manufacturing the vibration power generation element 10, the edge portion of the portion constituting the weight portion 1c is etched to protrude from the cantilever portion 1b in the direction connecting the free end 1ba side and the fixed end 1bb side of the cantilever portion 1b. A curved surface 1ca can be formed at the tip of the weight portion 1c (see FIG. 6C). In the method of manufacturing the vibration power generating element 10, the curved surface 1ca is formed at the tip of the weight portion 1c. For example, the weight portion 1c is obtained by using an etching solution obtained by diluting hydrofluoric acid and nitric acid with acetic acid. What is necessary is just to etch the edge part of the site | part which comprises. By increasing the ratio of nitric acid in the etching solution, it becomes possible to form a curved surface at a portion constituting the weight portion 1c made of a silicon material. In the method for manufacturing the vibration power generation element 10, the shape of the weight portion 1c can be adjusted by forming an etching mask in an appropriate shape in advance in a portion constituting the weight portion 1c.

  In the vibration power generation device 30 of the present embodiment, the first support portion 1a of the vibration power generation element 10 is provided on the one surface 1bc side of the cantilever part 1b in the vibration power generation element 10 formed by the method for manufacturing the vibration power generation element 10 described above. The cover substrate 20a is fixed. In the vibration power generation apparatus 30 of the present embodiment, the second cover substrate 20b is fixed to the support portion 1a of the vibration power generation element 10 on the other surface 1bd side of the cantilever portion 1b. The first cover substrate 20a has a C shape in a cross section perpendicular to the direction connecting the free end 1ba side and the fixed end 1bb side of the cantilever portion 1b, and has a half-tubular shape as a whole. Similarly, the second cover substrate 20b has a C-shape in a cross section perpendicular to the direction connecting the free end 1ba side and the fixed end 1bb side of the cantilever portion 1b, and has a half-tube shape as a whole. Yes. In the vibration power generation apparatus 30 according to the present embodiment, the first cover substrate 20a, a part of the vibration power generation element 10, and the second cover substrate 20b constitute a housing portion 20. In the housing part 20, the first cover substrate 20a, the vibration power generation element 10, and the second cover substrate 20b constitute a through hole 30a through which the fluid can pass. The housing part 20 accommodates the cantilever part 1b in the through hole 30a along the direction connecting the free end 1ba side and the fixed end 1bb side of the cantilever part 1b in the direction of the through hole 30a. Note that the first cover substrate 20a has a displacement space in which the cantilever portion 1b and the weight portion 1c swing on the vibration power generation element 10 side so as to allow the fluid to pass therethrough. A glass substrate or a silicon substrate provided with a groove part of the hole 30a may be used.

  The second cover substrate 20b has a displacement space in which the cantilever portion 1b swings on the side of the vibration power generation element 10 between the base substrate 1 and a part of the through hole 30a through which the fluid can pass. A glass substrate or a silicon substrate provided with a groove to be formed may be used. Further, the second cover substrate 20b is appropriately provided with a contact electrode (not shown) that can be connected to the first pad electrode 8a and the second pad electrode 8b of the vibration power generation element 10 and output to the outside. You can do it. Here, the first cover substrate 20a and the vibration power generation element 10 can be bonded by, for example, a room temperature bonding method, a resin bonding method using an epoxy resin, an anodic bonding method, or the like. Similarly, the second cover substrate 20b and the vibration power generation element 10 can be bonded by, for example, a room temperature bonding method, a resin bonding method using an epoxy resin, an anodic bonding method, or the like.

  The housing portion 20 uses not only the first cover substrate 20a, the vibration power generation element 10 and the second cover substrate 20b to form the through hole 30a, but also the first cover substrate 20a and the second cover. The substrate 20b may constitute the through hole 30a. Moreover, the housing part 20 is not restricted only to a rectangular tube shape, and can be various shapes such as a cylindrical shape.

  In order to manufacture the vibration power generation apparatus 30 including the first cover substrate 20a and the second cover substrate 20b, the base substrate 1 that has been processed into the element formation substrate 11 shown in FIG. A first cover joining step for joining one cover substrate 20a is performed. Similarly, the method for manufacturing the vibration power generation apparatus 30 performs the second cover bonding step of bonding the second cover substrate 20b to the base substrate 1 that has been processed into the element formation substrate 11. The manufacturing method of the vibration power generator 30 is performed at a wafer level until the first cover bonding process and the second cover bonding process are completed, and then a dicing process is performed to divide the vibration power generation apparatus 30 into a mass-productive product. The vibration power generator 30 can be manufactured.

  The vibration power generation apparatus 30 performs the vibration power generation in which the die-sync process of dividing into individual vibration power generation elements 10 is performed after the process up to the end of the processing to the element formation substrate 11 shown in FIG. The vibration power generation apparatus 30 may be manufactured by housing the element 10 in the housing portion 20.

  In the vibration power generation device 30 of the present embodiment, the tip of the weight portion 1c protruding from the cantilever portion 1b forms a curved surface 1ca in the direction connecting the free end 1ba and the fixed end 1bb of the cantilever portion 1b. In the vibration power generator 30 of the present embodiment, the free end 1ba side of the cantilever part 1b is the upstream side of the fluid, and the fixed end 1bb side of the cantilever part 1b is the downstream side of the fluid. In the vibration power generator 30 of the present embodiment, the fluid flowing from the upstream flows along the curved surface 1ca provided at the tip of the weight portion 1c when passing through the through hole 30a. The vibration power generator 30 has a higher flow velocity than the flow along the other surface 1bd side of the cantilever portion 1b, so that the flow of the fluid along the curved surface 1ca is faster than the second cover substrate 20b side. The pressure on the one cover substrate 20a side is relatively lowered. Thereby, the vibration power generator 30 is displaced in a direction in which the free end 1ba side of the cantilever portion 1b approaches the first cover substrate 20a side. In addition, when the cantilever portion 1b exceeds a certain amount of displacement, the vibration power generator 30 tries to return the cantilever portion 1b to the original position due to the elastic force of the cantilever portion 1b.

  In the vibration power generator 30 of the present embodiment, the load of the weight portion 1c is applied to the free end 1ba side of the cantilever portion 1b. Moreover, the force which presses the weight part 1c is added to the vibration electric power generating apparatus 30 with the said fluid which flows from upstream along the curved surface 1ca provided in the front-end | tip of the weight part 1c. Therefore, in the vibration power generation device 30, the cantilever portion 1b that has returned to the original position side is displaced in a direction in which it is pressed toward the second cover substrate 20b. In addition, when the cantilever portion 1b exceeds a certain amount of displacement, the vibration power generator 30 tries to return the cantilever portion 1b to the original position due to the elastic force of the cantilever portion 1b. The vibration power generation apparatus 30 is piezoelectrically converted as compared with a case where a vibration power generation element in which the cantilever portion 1b is self-excited and the tip portion does not have the weight portion 1c having the curved surface 1ca by repeating such an operation. It is considered that the amount of displacement of the portion 3 can be increased to further increase the power generation efficiency. In other words, the vibration power generator 30 generates self-excited vibration in the cantilever portion 1b due to a pressure difference between the one surface 1bc side and the other surface 1bd side generated by the fluid, the elastic force of the cantilever portion 1b, and the like. It becomes possible.

  In the vibration power generation apparatus 30 of the present embodiment, the AC voltage generated by the piezoelectric conversion unit 3 becomes a sinusoidal AC voltage corresponding to the vibration of the piezoelectric conversion unit 3. The vibration power generation apparatus 30 can generate power using the self-excited vibration generated by the fluid flowing through the through-hole 30a. The vibration power generator 30 can adjust the resonance frequency of self-excited vibration by appropriately selecting the structure, size, material, and the like of the cantilever part 1b, the weight part 1c, and the piezoelectric conversion part 3.

  Note that the vibration power generation apparatus 30 of the present embodiment includes a rectifier circuit configured by a two-phase full-wave rectifier circuit that rectifies the two-phase alternating current output from the first pad electrode 8a and the second pad electrode 8b of the vibration power generation element 10. A portion (not shown) may be provided. Further, the vibration power generation device 30 can include a power storage element that is electrically connected to both ends of the output end of the rectifier circuit unit. Furthermore, the vibration power generation apparatus 30 appropriately includes a DC / DC conversion unit between a power storage element and a load connected to the vibration power generation apparatus 30 (not shown), and supplies a voltage supplied to the load side according to the capacity of the load. A configuration in which the voltage is increased or decreased as appropriate may be employed.

(Embodiment 2)
The vibration power generation apparatus 30 of the present embodiment shown in FIG. 7 is mainly different from the first embodiment of FIG. 1 in that the vibration power generation element 10 is accommodated in the structure of the vibration power generation element 10 and the through hole 30a of the housing portion 20. Is different. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 1, and description is abbreviate | omitted suitably.

  The vibration power generation apparatus 30 of the present embodiment includes a cantilever portion 1b, a weight portion 1c provided on the free end 1ba side of the cantilever portion 1b, and a piezoelectric conversion portion 3 that generates power by receiving stress generated by the swinging of the cantilever portion 1b. The vibration power generation element 10 is included. The vibration power generator 30 has a housing portion 20 having a through hole 30a through which a fluid can pass. The housing part 20 of the vibration power generation apparatus 30 has the cantilever part 1b of the vibration power generation element 10 in the through hole 30a along the direction connecting the free end 1ba side and the fixed end 1bb side of the cantilever part 1b in the direction of the through hole 30a. It is stored. In the vibration power generation apparatus 30, the tip of the weight portion 1c protruding from the cantilever portion 1b is curved 1ca in the direction in which the weight portion 1c of the vibration power generation element 10 connects at least the free end 1ba side and the fixed end 1bb side of the cantilever portion 1b. Is configured.

  In the vibration power generation apparatus 30 of the present embodiment, the housing part 20 has a supply port 21aa to which the fluid is supplied and a supply part provided with a supply pipe 21a communicating with the free end 1ba side of the cantilever part 1b in the through hole 30a. 21 is provided. The housing portion 20 includes a discharge portion 22 having a discharge port 22aa for discharging the fluid and provided with a discharge pipe 22a communicating with the fixed end 1bb side of the cantilever portion 1b in the through hole 30a.

  Similar to the vibration power generation apparatus 30 of the first embodiment, the vibration power generation apparatus 30 of the present embodiment can obtain a power generation output from the piezoelectric conversion unit 3 as the cantilever portion 1b swings. In the vibration power generation apparatus 30 of the present embodiment, the upper side of the paper surface of FIG. 7 is the vertical upward direction, and the vibration power generation element 10 is provided with the weight portion 1c on the upper side in the vertical direction as the surface side of the cantilever portion 1b. Are arranged as follows. Thereby, even if the cantilever part 1c will be in the state in which the vibration electric power generating apparatus 30 of this embodiment will bend by the dead weight of the weight part 1c, it will become possible to suppress blocking the flow of the said fluid.

  In the vibration power generator 30 of the present embodiment, a fixed end 1bb opposite to the free end 1ba side of the cantilever portion 1b provided with the weight portion 1c is appropriately attached to the support portion 1a provided in advance in the housing portion 20 with an adhesive or the like. The vibration power generation element 10 is housed in the housing part 20. In the vibration power generation device 30 of the present embodiment, the vibration power generation element 10 includes a flat metal plate constituting the first electrode 3a1, a piezoelectric layer 3a3 formed on the metal plate, and the piezoelectric layer 3a3. The cantilever part 1b is comprised with the flat metal plate which comprises the formed 2nd electrode 3a2. That is, in the vibration power generation element 10 of the vibration power generation apparatus 30 of the present embodiment, the cantilever portion 1 b also serves as the piezoelectric conversion portion 3. The vibration power generation element 10 of the vibration power generation apparatus 30 in FIG. 7 is a piezoelectric layer, whereas the vibration power generation element 10 in the first embodiment in FIG. 1 is a thin film type piezoelectric element manufactured using a MEMS manufacturing technique. A bulk type piezoelectric element using a bulk piezoelectric material is configured as 3a3. The vibration power generation element 10 has a hemispherical weight 1c protruding from the cantilever part 1b on the upper side in the vertical direction of the cantilever part 1b. The weight portion 1c can be formed by fixing a weight portion 1c made of a metal material or the like formed separately from the cantilever portion 1b using an adhesive or the like.

  As in the first embodiment, the vibration power generator 30 according to the present embodiment has a cantilever portion due to the pressure difference between the one surface 1bc side and the other surface 1bd side generated by the fluid, the elastic force of the cantilever portion 1b, and the like. It becomes possible to generate self-excited vibration in 1b. In the vibration power generation apparatus 30 according to the present embodiment, although not shown, wiring is appropriately provided to generate electric power by the piezoelectric conversion unit 3 and to output electric power output from the first electrode 3a1 and the second electrode 3a2 to the housing unit. What is necessary is just to comprise so that it can take out of 20 outside. The vibration power generation apparatus 30 may be configured with an insulating film as necessary so that the first electrode 3a1 and the second electrode 3a2 of the vibration power generation element 10 are not short-circuited.

  As shown in FIG. 8, the vibration power generation apparatus 30 of the present embodiment is configured using a vibration power generation element 10 in which a hemispherical weight portion 1 c protrudes from the cantilever portion 1 b on the lower side in the vertical direction of the cantilever portion 1 b. May be. Further, as shown in FIG. 9, the vibration power generation apparatus 30 of the present embodiment uses a MEMS manufacturing technique in which a hemispherical weight portion 1 c is protruded from the cantilever portion 1 b on the lower side in the vertical direction of the cantilever portion 1 b. You may comprise using the vibration electric power generation element 10 manufactured in this way. Furthermore, as shown in FIG. 10, the vibration power generator 30 of the present embodiment projects a hemispherical weight 1c from the cantilever 1b on the upper side in the vertical direction of the cantilever 1b, and the cantilever 1b is supported by the support 1a. Can be configured using the vibration power generation element 10 inclined with respect to the vertical direction and the horizontal direction. In the vibration power generation device 30 using the vibration power generation element 10 shown in FIG. 10, the vibration power generation element 10 and the housing portion 20 are configured so that the size of the gap between the cantilever portion 1 b and the inner wall 20 aa of the through hole 30 a is the cantilever portion. It can be made different between the fixed end 1bb side of 1b and the free end 1ba side. In the vibration power generation device 30 using the vibration power generation element 10 shown in FIG. 10, compared with the vibration power generation device 30 in FIG. 7, the pressure between the one surface 1bc side and the other surface 1bd side generated by the fluid is the cantilever portion 1 b side. The difference can be generated more stably.

(Embodiment 3)
The vibration power generation apparatus 30 according to the present embodiment illustrated in FIG. 11 includes an inflow amount control unit 23 that controls the inflow amount of the fluid in the supply unit 21 of the housing unit 20 as compared with the vibration power generation apparatus 30 according to the second embodiment. The point is mainly different. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 2, and description is abbreviate | omitted suitably.

  The vibration power generator 30 of the present embodiment includes a supply unit 21 having a supply port 21aa through which fluid is supplied to the housing unit 20 and provided with a supply pipe 21a communicating with the free end 1ba side of the cantilever unit 1b in the through hole 30a. I have. Further, the vibration power generator 30 includes a discharge portion 22 provided in the housing portion 20 with a discharge port 22aa for discharging the fluid and a discharge pipe 22a communicating with the fixed end 1bb side of the cantilever portion 1b in the through hole 30a. ing. In the vibration power generation apparatus 30 of the present embodiment, the vibration power generation element 10 having the same configuration as that of the vibration power generation element 10 of the second embodiment shown in FIG. 10 is used. Therefore, the size of the gap between the cantilever portion 1b and the inner wall 20aa of the through hole 30a between the vibration power generation element 10 and the housing portion 20 of the vibration power generation device 30 is such that the fixed end 1bb side and the free end 1ba of the cantilever portion 1b. It is different on the side. In the vibration power generator 30 of the present embodiment, the free end 1ba side of the cantilever part 1b is shifted to the support part 1a side from the fixed end 1bb side of the cantilever part 1b in the thickness direction of the cantilever part 1b.

  Further, in the vibration power generation apparatus 30 of the present embodiment, the housing 20 has the above fluid on the one surface 1bc side compared to the other surface 1bd side opposite to the one surface 1bc side on the cantilever portion 1b provided with the weight portion 1c. The supply unit 21 is provided with an inflow amount control unit 23 for increasing the inflow amount. Here, in the vibration power generation apparatus 30 of the present embodiment, the supply unit 21 including the inflow amount control unit 23 is formed integrally with the housing unit 20. The inflow amount control unit 23 reduces the opening area of the supply pipe 21a from the supply port 21aa side toward the discharge port 22aa side. As a result, the vibration power generation apparatus 30 of the present embodiment can cause more fluid to flow along the curved surface 1ca side of the weight portion 1c as compared with the vibration power generation apparatus 30 of the second embodiment. Therefore, the vibration power generator 30 of this embodiment has a larger pressure difference between the one surface 1bc side and the other surface 1bd side generated by the fluid than the vibration power generator 30 of the second embodiment. It becomes possible to do.

  The inflow amount control unit 23 is not limited to being formed integrally with the housing unit 20, and as shown in FIG. 12, the inflow amount control unit 23 having a triangular prism shape formed separately from the housing unit 20 is provided in the housing unit 20. It may be fixed using an adhesive or the like. Further, the inflow rate control unit 23 is not limited to the structure having the inclined plane shown in FIG. 12, and only the surface on the supply port 21aa side as shown in FIG. It is good also as a structure. The vibration power generator 30 shown in FIG. 13 has a fluid (indicated by a one-dot chain line in FIG. 13) along the surface of the inflow control unit 23 having a structure in which only the surface on the supply port 21aa side has a curved surface. Flow), and more fluid can flow along the curved surface 1ca side of the weight portion 1c. Similarly, as shown in FIG. 14, the inflow rate control unit 23 may have a structure in which a semi-cylindrical inflow rate control unit 23 is provided in the supply unit 21. In the vibration power generator 30 shown in FIG. 14, a fluid (see an arrow of a one-dot chain line in FIG. 14) flows along the surface of the semi-cylindrical inflow control unit 23, and a larger amount of the fluid flows on the curved surface of the weight portion 1 c. It can be along the 1ca side.

(Embodiment 4)
The vibration power generation apparatus 30 according to the present embodiment illustrated in FIG. 15 is mainly different from the vibration power generation apparatus 30 according to the third embodiment illustrated in FIG. 14 in the structure of the supply unit 21 including the inflow control unit 23. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 3, and description is abbreviate | omitted suitably.

  The vibration power generation apparatus 30 of the present embodiment has a supply port 21aa through which fluid (see an arrow of a one-dot chain line in FIG. 15) is supplied to the housing part 20, and communicates with the free end 1ba side of the cantilever part 1b in the through hole 30a. A supply unit 21 provided with a supply pipe 21a is provided. Further, the vibration power generator 30 includes a discharge portion 22 provided in the housing portion 20 with a discharge port 22aa for discharging the fluid and a discharge pipe 22a communicating with the fixed end 1bb side of the cantilever portion 1b in the through hole 30a. ing.

  In the vibration power generator 30 according to the present embodiment, the housing portion 20 has the fluid inflow on the one surface 1bc side as compared to the other surface 1bd side opposite to the one surface 1bc side on the cantilever portion 1b provided with the weight portion 1c. The inflow amount control unit 23 is provided in the supply unit 21 so as to increase the amount. In particular, the vibration power generation apparatus 30 of the present embodiment includes the tapered supply unit 21 that reduces the opening area of the supply pipe 21a from the supply port 21aa side to the discharge port 22aa side.

  In the vibration power generation device 30 of the present embodiment, the vibration power generation element 10 includes a weight portion 1c on the upper side in the vertical direction of the cantilever portion 1b. The vibration power generation element 10 is a bottom view of the vibration power generation element 10 in FIG. The vibration power generation apparatus 30 bends the cantilever part 1b with its own weight of the weight part 1c and, together with the inflow control part 23, the other surface 1bd side opposite to the one surface 1bc side of the cantilever part 1b provided with the weight part 1c. As compared with the above, the inflow amount of the fluid on the one surface 1bc side may be increased.

Here, the vibration power generation apparatus 30 of the present embodiment can also be configured using the vibration power generation element 10 having the structure shown in FIG. Moreover, the vibration power generation apparatus 30 of this embodiment can also be comprised using the vibration power generation element 10 shown in FIG. The vibration power generation element 10 shown in FIG. 18 includes a stress generating film 4 that generates stress that causes the cantilever portion 1b to bend in the cantilever portion 1b. In the vibration power generation element 10 shown in FIG. 18, the stress generating film 4 is provided on the piezoelectric conversion portion 3 of the cantilever portion 1b. The stress generating film 4 can be formed by, for example, a SiO ₂ film or a Si ₃ N ₄ film formed on the piezoelectric conversion unit 3. The stress generating film 4 can control the stress that causes the cantilever portion 1b to bend by adjusting the material of the stress generating film 4, the thickness of the stress generating film 4, and the like. In the vibration power generation element 10 shown in FIG. 18, due to the bending of the cantilever portion 1b, the size of the gap between the cantilever portion 1b and the inner wall 20aa of the through hole 30a is such that the fixed end 1bb side and the free end 1ba side of the cantilever portion 1b It will be different. Therefore, in the vibration power generation device 30, the vibration power generation element 10 and the housing part 20 make the gaps different in size between the fixed end 1bb side and the free end 1ba side of the cantilever part 1b. It is also possible to increase the amount of the fluid that comes into contact with the curved surface 1ca. The stress generating film 4 may be provided on the cantilever portion 1b, and may be provided on the one surface 1bc side of the cantilever portion 1b, or may be provided on the other surface 1bd side of the cantilever portion 1b. The stress generating film 4 may be provided on both the one surface 1bc side and the other surface 1bd side of the cantilever portion 1b. The vibration power generation apparatus 30 separately forms the stress generating film 4 that causes the cantilever portion 1b to bend. However, the cantilever portion 1b itself can be selected by appropriately selecting the material and the film thickness constituting the vibration power generation element 10. It is also possible to provide an initial deflection that causes deflection.

(Embodiment 5)
The vibration power generation apparatus 30 of the present embodiment shown in FIG. 19 is mainly different from the third embodiment of FIG. 11 in the structure of the discharge part 22 of the housing part 20. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 3, and description is abbreviate | omitted suitably.

  The vibration power generation apparatus 30 of the present embodiment has a supply port 21a having a supply port 21aa through which the fluid is supplied to the housing unit 20 and having a supply pipe 21a communicating with the free end 1ba side of the cantilever portion 1b in the through hole 30a. It has. The vibration power generator 30 includes a discharge portion 22 having a discharge port 22aa for discharging the fluid in the housing portion 20 and a discharge pipe 22a communicating with the fixed end 1bb side of the cantilever portion 1b in the through hole 30a. Yes.

  In the vibration power generator 30 according to the present embodiment, the housing portion 20 has the fluid inflow on the one surface 1bc side as compared to the other surface 1bd side opposite to the one surface 1bc side on the cantilever portion 1b provided with the weight portion 1c. The supply unit 21 is provided with an inflow amount control unit 23 for increasing the amount. Further, in the vibration power generation apparatus 30 of the present embodiment, the housing 20 has the above fluid on the one surface 1bc side compared to the other surface 1bd side opposite to the one surface 1bc side on the cantilever portion 1b provided with the weight portion 1c. The outflow amount control unit 26 is provided to increase the outflow amount.

  That is, in the vibration power generation apparatus 30 of the present embodiment, the discharge unit 22 includes the outflow amount control unit 26 in which the housing unit 20 increases the opening area of the discharge pipe 22a from the supply port 21aa toward the discharge port 22aa. ing. The outflow amount control unit 26 can be formed in the same manner as the inflow amount control unit 23.

  The discharge part 22 is not limited to the one provided with the outflow amount control part 26 having the inclined plane shown in FIG. 19, and the discharge pipe 22a of the discharge pipe 22a from the supply port 21aa side to the discharge port 22aa side shown in FIG. A taper-shaped outflow control unit 26 that increases the opening area may be provided. The vibration power generation apparatus 30 shown in FIG. 20 can discharge the fluid to the outside more efficiently than the vibration power generation apparatus 30 shown in FIG. Therefore, the vibration power generation apparatus 30 shown in FIG. 20 can increase the power generation efficiency more than the vibration power generation apparatus 30 shown in FIG.

DESCRIPTION OF SYMBOLS 1b Cantilever part 1ba Free end 1bb Fixed end 1c Weight part 1ca Curved surface 3 Piezoelectric conversion part 4 Stress generating film 10 Vibration power generation element 20 Housing part 20aa Inner wall 21 Supply part 21a Supply pipe 21aa Supply port 22 Discharge part 22a Discharge pipe 22aa Inflow control unit 26 Outflow control unit 30 Vibration power generator 30a Through hole

Claims (9)

A vibration power generating element including a cantilever portion, a weight portion provided on the free end side of the cantilever portion, and a piezoelectric conversion portion that generates power in response to stress generated by the swinging of the cantilever portion, and a through-hole through which fluid can pass A housing part that accommodates the cantilever part in the vibration power generation element in the through-hole along a direction connecting the free end side and the fixed end side of the cantilever part in the direction of the through-hole. A vibration power generator having
The weight generator is characterized in that the tip of the weight protruding from the cantilever part forms a curved surface at least in a direction connecting the free end side and the fixed end side of the cantilever part. apparatus.   The housing portion has a supply port to which the fluid is supplied, a supply portion provided with a supply pipe communicating with the free end side of the cantilever portion in the through hole, and a discharge port for discharging the fluid. The vibration power generator according to claim 1, further comprising a discharge portion provided with a discharge pipe communicating with the fixed end side of the cantilever portion in the through hole.   The housing portion is provided with an inflow amount control unit for increasing the inflow amount of the fluid on the one surface side as compared with the other surface side opposite to the one surface side of the cantilever portion provided with the weight portion. The vibration power generation apparatus according to claim 2, wherein the vibration power generation apparatus is provided in a portion.   4. The vibration power generation apparatus according to claim 3, wherein the inflow amount control unit has a tapered shape that decreases an opening area of the supply pipe from the supply port side toward the discharge port side.   The said housing part is equipped with the taper-shaped outflow amount control part which makes the opening area of the said discharge pipe large from the said supply port side toward the said discharge port side, The said discharge part is characterized by the above-mentioned. The vibration power generator described in 1.   The vibration power generation element and the housing portion are different in that the size of the gap between the cantilever portion and the inner wall of the through hole is different between the fixed end side and the free end side of the cantilever portion. The vibration power generator according to any one of claims 1 to 5, wherein the vibration power generator is characterized in that:   The vibration power generation device according to claim 6, wherein the vibration power generation element has a size of the gap that is different between the fixed end side and the free end side of the cantilever part due to the bending of the cantilever part. .   The vibration power generation device according to claim 7, wherein the vibration power generation element includes a stress generation film that generates stress that causes the bending in the cantilever portion.   The vibration power generation device according to any one of claims 1 to 8, wherein the vibration power generation element includes the weight portion on an upper side in a vertical direction of the cantilever portion.

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