JP2023073156A - Surface mountable thin piezoelectric blower device - Google Patents

Abstract

To meet a demand of a piezoelectric blower device which can be applied to a lot of applications which need the piezoelectric blower device to be incorporated in a small and thin device, as typified by a portable terminal, to handle high pressure air at a large flow rate.SOLUTION: In a thin piezoelectric blower device, a one-way valve function is provided at a center in a diaphragm which is displaced in a swinging manner so that swinging of the one-way valve follows a drive frequency when the piezoelectric blower device is downsized and its drive frequency becomes high, and a flow of fluid is adjusted from a hole made at a piezoelectric element center part. Further, metal materials having high strength are joined in a laminated manner to form a cavity and a blower housing. Furthermore, forms of electric connection and passage connection which are designed assuming that the piezoelectric blower device is mounted on a portable terminal in advance are created.SELECTED DRAWING: Figure 1

Description

The present invention relates to the structure of a thin piezoelectric blower device suitable for being incorporated in small electronic devices such as mobile terminals.

Piezoelectric blower devices that use a piezoelectric element as an actuator to operate a diaphragm at a drive frequency in the high-frequency range to blow out gas, especially configurations devised for miniaturization, have been applied for many times over the years. be. (Patent Document 1, Patent Document 2, Patent Document 3, Patent Document 4, Patent Document 5)

In Patent Document 1, a pump body includes a pump body, a displacement device that is displaced by driving means, and a pump chamber formed between the displacement device and the pump body, the pump chamber having no check valve. Fluidly connected to the inlet and the outlet through the opening and the second opening, the displacer comprises a plate-like or diaphragm-like member fixed to the pump body, and the pump body has a pump chamber. is provided, an elastic buffer is provided in contact with the pump chamber, the operating force of the driving means acts on a portion of the displacer facing the first opening, and the displacer closes the first opening in its first end position and leaves the first opening open in its second end position, the driving means operating the displacer, based on the movement of the displacer. The case of a fluid pump without a non-return valve is shown which causes deformation of the buffer and the deformation of the buffer causes the fluid to drain or enter through the second opening.

However, in the configuration shown in Patent Document 1, a large differential pressure does not occur unless the relationship of the pump volume that changes according to the operation of the displacement unit >> the internal volume of the buffer is established. must be limited to very small buffer volumes to cause deformation of the buffer. Therefore, the amount of fluid discharged is small, and since the fluid is discharged by the restoring force of the buffer, there is a problem that the back pressure on the outlet side is also small.

Patent Document 2 discloses an actuator that displaces a movable wall such as a piston or a diaphragm, a driving means that drives and controls the actuator, a pump chamber whose volume can be changed by displacement of the movable wall, and a working fluid that is supplied to the pump chamber. A pump comprising an inlet channel for inflow and an outlet channel for outflow of working fluid from the pump chamber, wherein the outlet channel communicates with the pump chamber during pump operation, and the combined inertance value of the inlet channel is is smaller than the combined inertance value of the outlet flow path, the inlet flow path includes a fluid resistance element that is smaller than the fluid resistance when the working fluid flows out of the pump chamber, and the drive The means includes period control means for changing the motion period of the movable wall, and the period control means starts the pump chamber volume compression process of the movable wall when the pressure in the pump chamber reaches absolute zero atmospheric pressure. An example of a fluid pump is shown, which drives the actuator to do so.

However, in the configuration shown in Patent Document 2, a piezoelectric element that expands and contracts in the vertical direction is assumed as an actuator for operating the piston or diaphragm. In order to obtain the displacement, it is essential to use a laminated piezoelectric element, and there is a problem that the height of the pump is increased and it is difficult to mount it on a thin portable terminal.

In Patent Document 3, a first wall portion of a blower body forming a blower chamber with a diaphragm, and a portion of the first wall portion facing the center portion of the diaphragm are formed to separate the inside and the outside of the blower chamber. and a second wall provided on the opposite side of the blower chamber with the first wall in between and spaced apart from the first wall, facing the first opening a second opening formed at a portion of the second wall portion formed between the second wall portion and the first wall portion and the second wall portion; an outer end portion communicating with the outside; an inflow passage connected to an opening and a second opening; and at an inner end of the inflow passage connected to the first opening and the second opening, more than the first opening and the second opening An example of a piezoelectric micro-blower is shown in which a central space having a large opening area is formed, and the portion of the first wall facing the central space vibrates as the diaphragm is displaced.

However, although the configuration shown in Patent Document 3 can deliver compressible fluid by inertial force, there is no check valve, so the flow rate fluctuation due to external pressure is large, and the product function is extremely limited in applications where this device is installed. The problem was that it was limited. Even if the piezoelectric blower device is miniaturized, it is desirable to have a configuration that can deliver a compressible fluid at a large flow rate and at a high pressure.

In Patent Document 4, a first diaphragm, a second diaphragm facing the first diaphragm, a peripheral wall portion connecting the peripheral edge portion of the first diaphragm and the peripheral edge portion of the second diaphragm, and the A pump chamber positioned between the first diaphragm and the second diaphragm and defined by the first diaphragm, the second diaphragm and the peripheral wall portion, and bending the first diaphragm and the second diaphragm a driving body that vibrates to cause pressure fluctuations in the pump chamber, and the first diaphragm has an axis perpendicular to the central portion of the first diaphragm and the central portion of the second diaphragm. A first hole is provided at a position that overlaps with the axis when viewed along the extending direction, and is not provided with a check valve. On one side, a second hole is arranged at a position not overlapping with the first hole when viewed along the extending direction of the axis, and is provided with a check valve. At least one of the diaphragm and the second diaphragm is arranged in an area outside the area in which the second hole is provided when viewed along the extending direction of the axis centered on the axis. and further provided with a third hole not provided with a check valve.

The example shown in Patent Document 4 has been proposed as a structure capable of increasing the flow rate compared to the conventional example, but this example also does not describe the principle structure for obtaining a high discharge pressure. There was a problem that it could not be installed in a thin portable terminal for applications that require incompressible fluid to be delivered at a large flow rate and at a high pressure.

In U.S. Pat. No. 5,400,000, a substantially cylindrical shape defining a cavity for containing a fluid, said cavity being formed by side walls closed at both ends by substantially circular end walls, said end walls a pump body at least one of which is a driven end wall, said driven end wall having a central portion and a peripheral edge portion extending radially outwardly from said driven end wall central portion; , operatively associated with said central portion of said driven end wall for producing an oscillatory motion of said driven end wall, whereby in use said end wall of said driven end wall substantially an actuator for generating displacement vibrations in a substantially perpendicular direction with an annular node between the center of the driven end wall and the side wall; Associated therewith is an isolator for reducing damping of said displacement oscillations; and a first opening disposed at any location in said cavity other than at said annular node location and extending through said pump body; a second opening disposed in the pump body at any position other than the position of the first opening and extending through the pump body; and at least one of the first opening and the second opening. wherein, in use, said displacement oscillations produce corresponding radial pressure oscillations of said fluid within said cavity of said pump body to open said first and second openings. An example is shown of a pump that causes fluid flow through.

In the case shown in U.S. Pat. No. 5,400,000, a vertically vibrating actuator creates an acoustic standing wave in the radial direction of a cylindrical cavity, thereby generating large amplitude pressure oscillations near the center of the cylindrical cavity. Compared to Patent Documents 3 and 4, this proposal is excellent as a principle configuration for delivering a compressible fluid to a high pressure. However, when attempting to manufacture a smaller blower based on this configuration, there are the following problems. The first is that when the cavity diameter is designed to be small in order to manufacture a compact blower, the resonance frequency increases due to the smaller cavity diameter, resulting in a valve (one-way valve) configured on the principle of being driven by differential pressure. There is a possibility that the oscillation will not catch up with the resonance frequency, and the function as a one-way valve will not be obtained. Even if it is miniaturized, it is not fully satisfactory for applications that require both a large flow rate and a high pressure.

Japanese Patent No. 3035854 Japanese Patent No. 5003700 Japanese Patent No. 4873014 Japanese Patent No. 6769568 Special table 2012-528980 publication

According to the above-mentioned fluid pump or blower, a piezoelectric element is used as an actuator to drive in a high frequency range, and the function of delivering fluid is realized with a simple configuration, which is a technical proposal that can be applied to small electronic devices. It is certain that However, these proposals are not satisfactory for applications that require a large flow rate and a high pressure by being incorporated in a thinner compact electronic device such as a portable terminal. For example, if you want to incorporate a function to pressurize the cuff and measure blood pressure in a mobile terminal or watch-type mobile device, or a similar function to suck pollen or air pollutants and detect or count them, When it is built into equipment, and when it is desired to apply it to a portable negative pressure treatment device, which is one of the medical devices, which suctions the affected part of the wound to enhance the granulation effect, the blower device can be made thinner and the flow rate can be increased. Moreover, a high pressure is an essential condition.

The present invention is a specific piezoelectric blower device that can be made thinner for the purpose of being incorporated in thinner and smaller electronic equipment, which is expected to continue to be in demand in future social life represented by mobile terminals. It is to propose a typical configuration.

A piezoelectric blower according to the present invention comprises a circular diaphragm with a thickness of 100 μm or less that is displaced and vibrated by a piezoelectric element, and a one-way valve mechanism that actively operates in accordance with the displacement and vibration of the diaphragm. The central axis of the one-way valve mechanism is aligned with the maximum and minimum values of standing pressure waves generated by radial vibrations (longitudinal waves) of the fluid in the cylindrical cavity. The piezoelectric element attached to the diaphragm surface, which is the fluid outlet side of the one-way valve mechanism, is cylindrical and has a fluid communication hole in the center. Align the central axis of the fluid conduction hole with the position where the maximum and minimum values are obtained. The pressure standing wave generated in the cylindrical cavity is selectively opened and closed in synchronization with the displacement vibration by a one-way valve built into the diaphragm, and the high-pressure phase fluid in the cylindrical cavity is at the center of the piezoelectric element. It will be delivered to the outside through the fluid conduction hole formed in the . The diaphragm vibrates with its circular edge fixed by bonding, and induces the delivery of fluid to the outside by bending displacement caused by voltage application to the piezoelectric element attached to the thinned diaphragm. In order to form these structures in thin areas, diaphragms with one-way valve function are fabricated by diffusion bonding three layers of metal foil material. Also, the cylindrical cavity and the suction channel are integrally formed by diffusion bonding of metal foil material. An insulating layer and a conductive layer are formed on the surface of the diaphragm and are electrically connected to the piezoelectric element by wire bonding.

In the present invention, since the followability of the one-way valve to the increase in drive frequency accompanying size reduction can be maintained, it can be incorporated in thin and small electronic devices, such as mobile terminals, for various applications requiring large flow rates and high pressures. applications.

Moreover, by forming the main body by diffusion bonding of metal foil materials, the thickness of the piezoelectric blower device can be made extremely thinner compared to the conventional example, so that the degree of freedom in mounting is increased.

FIG. 1 is an external perspective view showing a typical product shape of a piezoelectric blower device 1 according to the present invention. FIG. 2A is a front view of a piezoelectric blower device 1 according to the invention. FIG. 2B is a schematic cross-sectional view of the piezoelectric blower device 1 according to the present invention as viewed in the direction of arrow A. FIG. FIG. 2C is a schematic cross-sectional view of the piezoelectric blower device 1 according to the present invention as seen from the arrow B direction. FIG. 3 is a schematic cross-sectional view enlarging the periphery of the one-way valve arranged in the piezoelectric blower device 1 according to the present invention. FIG. 4 is an exploded perspective view of the piezoelectric blower device 1 according to the present invention. A partially enlarged view shows the shape of the plurality of valve holes 14A-1 of the first valve hole layer 14A shown in the exploded perspective view. FIG. 5A is a schematic cross-sectional view explaining that the one-way valve has closed. FIG. 5B is a schematic cross-sectional view explaining that the one-way valve has been opened. FIG. 6 is a schematic diagram showing the principle of diffusion bonding. FIG. 7 shows an example of the thickness configuration of the diaphragm 14 laminated and bonded using the principle of diffusion bonding. FIG. 8 is a perspective view showing a preferred method of mounting the piezoelectric blower device 1 according to the present invention.

FIG. 1 is a perspective view showing a typical external shape of a piezoelectric blower device 1 according to the present invention. A circular piezoelectric element 30 having a fluid conducting hole 31 in the center is attached to a diaphragm surface 14 (not shown) of a substantially rectangular blower body 10 formed by joining multiple layers of metal foil materials by a metal diffusion bonding method. . Two voltage-applying lands 41 and 42 for driving the piezoelectric element 30 are provided in a diagonal region which is joined to the substantially rectangular blower body 10 and does not vibrate as the diaphragm 14 . One of them is a GND land 41, which is electrically connected to an electrode surface 30B (not shown) formed on the lower surface of the piezoelectric element 30 and the substantially rectangular blower body 10 made of a conductive metal material. It is The other is the SIG land 42. The SIG land 42 is formed on the insulating layer 20 by Au plating or Ag pattern printing. They are electrically connected by a thin bonding wire 50 made of Si material. In addition, fluid is sucked into the area where the diaphragm 14 is joined to the substantially rectangular blower body 10 and does not vibrate due to displacement and where the two voltage application lands 41 and 42 are not formed, and is introduced into the blower body. An INLET hole 60 is formed. A through-hole 70 may be formed in advance in a region that does not affect the blower function as in this embodiment, and used as a positioning hole when incorporating into a product.
By connecting a power supply device (not shown) to the two voltage application lands 41 and 42 and applying an AC voltage, the piezoelectric element 30 repeats compression and expansion, and pressurizes, rectifies, and delivers the fluid according to the principle described later. , the liquid is discharged in the direction of the arrow with the fluid conducting hole 31 drilled in the center of the piezoelectric element 30 as the OUTLET.

2A, 2B, 2C, and 3 show schematic cross-sectional views of the piezoelectric blower device 1 according to the present invention, and in particular, FIG. 3 shows the detailed structure of the one-way valve. Also, to better understand the construction of the present invention, FIG. 4 shows an exploded perspective view of a typical piezoelectric blower device 1 according to the present invention.
2B or 2C show respective cross-sectional views as seen from the direction of the arrow in FIG. 2A. 2B or 2C, the substantially rectangular blower body 10 is composed of four major blocks: a diaphragm layer 14, a cavity layer 13, a node layer 12, and a flow path layer 11, when viewed from the cross-sectional direction. These four layers are integrated by bonding metal foil materials by a metal diffusion bonding method, which will be described later. Two node holes 12A are formed in the node layer 12 arranged below the cavity layer 13, the flow path is connected from the INLET hole 60 through the flow groove 11A, and the fluid path is connected to the cavity 13A. ing.
Diaphragm layer 14 is further composed of three thin layers. From the bottom in FIG. 3, the valve hole layer 14A, the flap valve layer 14B, and the valve swinging space layer 14C are formed. Everything else is integrated.
The valve hole layer 14A is formed as a layer having four fan-shaped valve holes 14A-1. The flap valve 14B-1 has a through-hole 14B-2 formed at a central position that does not overlap with the four fan-shaped valve holes 14A-1 of the valve hole layer 14A. The flap valve 14B-1 is forcibly swung between the valve swinging spaces 14D-1 by two operation modes, which will be described later, and functions as a one-way valve. By laminating and joining the metal foil materials, the thin diaphragm 14 has a structure close to that of a bulk material while incorporating a one-way valve mechanism.

The metal diffusion bonding method has a great feature as a general-purpose and low-cost technique for forming a hollow structure. In the technical field of MEMS (Micro Electro Mechanical System), it is well known to manufacture fine structures and electronic circuits based on semiconductor silicon materials for the purpose of miniaturization. Semiconductor silicon materials are not always suitable when fine structures operate at high frequencies. In terms of the mechanical properties of the material, for example, when comparing the bending strength of SUS304 and single crystal silicon, SUS304 is about three times higher. In addition, SUS304 has higher ductility and thus has the advantage of being less likely to crack. It is conceivable that it is commercially desirable to select metal materials within the range where fine processing is possible in order to avoid damage such as cracks in devices that repeatedly elastically deform at high frequencies. would be easy.
The piezoelectric element 30 is adhesively fixed to the surface of the diaphragm 14 . A non-conductive thermosetting epoxy resin adhesive or the like is selected for the adhesive 80 . The lower surface electrode 30B of the piezoelectric element 30 has surface roughness, and microscopically maintains electrical connection with the surface of the diaphragm 14 when pressure-bonded. On the other hand, the upper electrode 30A of the piezoelectric element 30 is electrically connected to the SIG land 42 by the bonding wire 50 described above.

5A and 5B are schematic cross-sectional views explaining that the one-way valve is opened and closed by the displacement vibration of the diaphragm 14. FIG. In FIG. 5A, an electric potential is applied to the upper electrode 32 of the piezoelectric element 30, the piezoelectric element 30 expands in the radial direction, strain deformation occurs between it and the diaphragm 14 restrained by the adhesive 80, and the diaphragm 14 is shown in FIG. A case of displacement in the middle-up direction is shown. In FIG. 5B, a positive potential is applied to the upper surface electrode 32 of the piezoelectric element 30, the piezoelectric element 30 is compressed in the radial direction, strain deformation occurs between the diaphragm 14 restrained by the adhesive 80, and the diaphragm 14 is shown in FIG. A case of displacement in the middle-down direction is shown. At this time, the flap valve 14B-1 built in the diaphragm 14 is forcibly swung in a direction opposite to the displacement direction of the diaphragm 14 relatively. When the diaphragm 14 is displaced upward as shown in FIG. 5A, the flap valve 14B-1 swings toward the valve swinging space layer side 14C-1 and locks in the first valve hole layer 14A, thereby delivering fluid to the outside. becomes impossible. When the diaphragm 14 is displaced downward, as shown in FIG. 5B, the flap valve 14B-1 swings toward the valve swinging space 14D-1 and is engaged with the piezoelectric element 30, thereby allowing the fluid to be delivered to the outside. becomes.

The flap valve 14B-1 is made of an extremely thin metal foil material of 10 μm or less and formed as a part of the flap valve layer 14B. Rolling of metals has been developed year by year, and it is possible to produce foil materials with a small surface roughness and a uniform thickness of several μm by rolling. When trying to reduce the size of the piezoelectric blower device 1 according to the present invention, the driving frequency of the diaphragm 14 will be higher, so considering the followability of the flap valve 14B-1, it is necessary to select a thinner material. It is expected that there will be
Since the flap valve 14B-1 is fixed between the valve hole layer 14A and the valve swinging space layer 14C by metal diffusion bonding, the elastic force of the metal material allows the peripheral portion including the through hole 14B-2 to swing. It's becoming Forcibly swinging the flap valve 14B-1 by the displacement vibration of the diaphragm 14 is more applicable to high-frequency driving than the conventional configuration in which the valve body is passively opened and closed by the pressure difference.

FIG. 6 is a schematic diagram showing the principle of metal diffusion bonding, which is the basis for manufacturing the piezoelectric blower device 1 according to the present invention. The figure is taken from "Q&A Diffusion Bonding" 1993, published by Sanpo Publishing, author: Osamu Ohashi. According to JIS, diffusion bonding is defined as "a method of joining base materials in close contact with each other, applying pressure to the extent that plastic deformation is minimized at a temperature below the melting point of the base materials, and utilizing the diffusion of atoms occurring on the bonding surfaces." defined as Diffusion bonding is the perfection of the joint (removal of the surface film, adhesion of the joint surface), and is derived from a joining mechanism that uses the diffusion of metal atoms. different from
It is well known that when clean metals come close to each other at the atomic level, atomic joints are easily formed at room temperature without melting. Commercially, in order to join metals using this phenomenon, a method of stacking metal materials with small surface roughness and joining them by heating and pressing in a vacuum is generally used. When heated to a certain temperature, the oxide film on the surface of the metal material disappears due to diffusion, exposing the metal atoms. Also, the pressure causes the metal crystals to creep, and the distance between the metal-to-metal joint surfaces is reduced and atomic diffusion progresses, completing the joint.
FIG. 6A shows a metal surface covered with an oxide film before heating.
FIG. 6B shows the process in which the oxide film disappears and the irregularities begin to undergo plastic deformation.
FIG. 6C shows the process of creep deformation.
(D) of FIG. 6 shows a process in which voids disappear due to diffusion.
There are several merits of diffusion bonding. 2) the ability to form hollow structures; 3) A high degree of freedom in selecting bonding materials for metal species. 4) It is easy to select a thin rolled material with small surface roughness to form a fine structure. etc. are worth mentioning.

FIG. 7 shows an example of the thickness configuration of the diaphragm 14 laminated and bonded using the principle of diffusion bonding. As described above, since the diaphragm 14 incorporates a one-way valve mechanism, a plurality of metal foil materials previously processed by etching or fine pressing into a shape that satisfies the function are overlapped and joined. Since the flap valve 14B-1 portion is not pressurized from the outside, it is maintained so as to be able to swing between the valve hole layer 14A and the valve swinging space layer 14C-1 even after diffusion bonding is performed. For example, if SUS304 is selected as the metal material, it is relatively easy to obtain and can be obtained at low cost with a small surface roughness. The thickness is generally in the range of t5 μm to t1000 μm, and the thickness of each layer constituting the diaphragm can be set as follows, for example.
Valve hole layer 14A: t30 μm
Flap valve layer 14B: t5 μm
Valve oscillation space layer 14C: t30 μm
In this example, the thickness of the diaphragm layer 14 after diffusion bonding is t65 μm, and the thickness can be adjusted to maximize the displacement of the diaphragm 14 . The thickness of each layer is not limited to this, and various thicknesses are selected according to the purpose of device design.

FIG. 8 is a schematic perspective view showing a mounting method of the piezoelectric blower device 1 according to the present invention. Since the main purpose of the present invention is to mount the piezoelectric blower device 1 on a small, thin electronic device represented by a portable terminal, consideration must also be given to thinning the mounting method of the piezoelectric blower device 1 . As shown in FIG. 1, the substantially rectangular blower body 10 has a piezoelectric element 30 having a fluid conduction hole 31, an INLET hole 60, and two voltage application terminals for driving the piezoelectric element 30. Lands 41 and 42 are provided on the same diaphragm 14 surface.
Separately from the piezoelectric blower device 1 , a flow path substrate 3 having a fluid flow path inside and an electronic circuit formed on the surface is prepared. The low-height fluid module 0 can be established by mounting the modules in the same manner. The spacer 4 is selected from, for example, a thermosetting adhesive sheet having adhesiveness. The fluid conducting hole 31 and the INLET hole 60 formed in the piezoelectric blower device 1 are adhered to the flow path formed inside the flow path substrate 3 so as not to leak around the hole, and are connected as a fluid path. Two voltage-applying lands 41 and 42 for driving the piezoelectric element 30 are connected to an electrical wiring pattern formed on the surface of the channel substrate 3 with conductive paste 5, metal microsprings, or the like. The flow path built in the flow path substrate 3 is manufactured by the above-mentioned metal diffusion bonding, and the structure in which the film substrates with wiring patterns are bonded to the upper and lower sides of the metal diffusion bonding makes it possible to achieve both thinness and strength for a small electronic device. It is considered preferable to install the
The film substrate may be a multi-layer substrate, and not only the piezoelectric blower device 1 according to the present invention is mounted, but also a pressure sensor die 3A, a resistor chip 3B, a capacitor chip 3C, an amplifier circuit 3D, a connector 3E, and a system via high-density wiring. The LSI 3F and the like can also be mounted on the film substrate at the same time to form the low-height fluid module 0 .
As shown in the figure, although the internal structure is different, if a piezoelectric valve device 2 manufactured by the same manufacturing method as the piezoelectric blower device 1 according to the present invention is also mounted, a small and thin cuff pressure blood pressure monitor can be obtained. As a module, it can be easily mounted on a small electronic device represented by a portable terminal, especially a wristwatch type information terminal.

The piezoelectric blower device 1 manufactured according to the present invention can be used, for example, in the field of information equipment, by incorporating a function of measuring blood pressure and a function of measuring CO2 concentration and dust concentration in the atmosphere into a portable terminal, and for industrial applications such as constant monitoring. can be considered.
For example, in medical applications, industrial applications such as negative pressure treatment devices, drainage devices, pressurization cuffs, apnea syndrome prevention devices, and respiratory aids that emphasize mobility are conceivable.
For example, in the automotive field, industrial applications are conceivable, such as preventing condensation in headlights, removing water droplets from back monitor cameras, preventing falling asleep, and evaporating air fresheners.
For example, in the personal field, industrial applications such as pocket fans and jackets with a built-in air cooling device can be considered.

0 low height fluid module
1 piezoelectric blower device
2 piezoelectric valve device
3 channel substrate 3A pressure sensor die 3B resistor chip 3C capacitor chip 3D amplifier circuit 3E connector 3F system LSI
4 spacer
5 Conductive paste (metallic microspring)
10 blower body 11 flow path layer 11A flow groove 12 node layer 12A node hole 13 cavity layer 13A cavity 14 diaphragm 14A valve hole layer 14A-1 valve hole 14B flap valve layer 14B-1 flap valve 14B-2 flap valve hole 14C valve Swing space layer 14C-1 Valve swing space 20 Insulating layer 30 Piezoelectric element 31 Fluid conduction hole 30A Upper surface electrode 30B Lower surface electrode 41 GND land 42 SIG land 50 Bonding wire 60 INLET hole 70 Through hole 80 Adhesive

Claims (3)

A flap valve with a thickness of 10 μm or less and a valve swinging space above the flap valve are provided in the center of a diaphragm with a thickness of 100 μm or less, which is repeatedly moved by the vibration of the piezoelectric element and is laminated and bonded with three layers of metal foil. , The diaphragm is repeatedly moved to forcibly swing the flap valve to rectify the fluid flow, and the center of the circular cavity formed directly under the diaphragm, the movable center of the flap valve built in the diaphragm, and the center of the piezoelectric element A piezoelectric blower configured to send fluid to the outside in one direction through a hole drilled in the center of a piezoelectric element, and an insulating layer and a conductive layer are formed on the diaphragm surface. 1. A thin piezoelectric blower device, characterized in that it is provided with a land for electrical connection for driving a piezoelectric element, and at the same time, a fluid introduction port is provided on the surface of a diaphragm. In the thin piezoelectric blower device shown in claim 1, the laminated diaphragm with a thickness of 100 μm or less containing the flap valve is integrally manufactured by laminating a plurality of (three layers) of metal foils and using a metal diffusion bonding method. configuration. The thin piezoelectric blower device shown in claims 1 and 2 is characterized in that the circular cavity and the fluid introduction channel that constitute the blower body are also integrally manufactured by laminating metal foils and by the metal diffusion bonding method. configuration.

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