JP4957504B2 - Piezoelectric pump and manufacturing method thereof - Google Patents

Description

  The present invention relates to a piezoelectric pump, and more particularly to a piezoelectric pump using a diaphragm that is bent and deformed by a piezoelectric element.

  Piezoelectric pumps are used for cooling water transportation pumps for small electronic devices such as notebook computers and fuel transportation pumps for fuel cells. Also, a piezoelectric pump can be used as a blower pump in place of a cooling fan such as a CPU or a blower pump for supplying oxygen necessary for power generation by a fuel cell. A piezoelectric pump is a pump using a diaphragm that bends and deforms when a voltage is applied to a piezoelectric element, and has an advantage of a simple structure, a thin configuration, and low power consumption (see Patent Document 1).

Here, a cross-sectional view of the gas pump of Patent Document 1 is shown in FIG. In this gas pump, an orifice hole 4d is provided in an electrostrictive vibrator 4 comprising a copper thin disc 4c and electrostrictive ceramic discs 4a and 4b having a small diameter, and the electrostrictive vibrator 4 is provided with a flange having a recess 2a. The electrostrictive vibrator 4 and the flange constitute a pump chamber 3, and the electrostrictive vibrator is driven at a high frequency to continuously discharge gas.
Japanese Unexamined Patent Publication No. 60-17279

  However, in the case of a piezoelectric blower that blows out air, it is practically necessary to resonate at a frequency of 20 kHz or more in order to operate at a frequency in a human non-audible range. When a circular piezoelectric element is arranged at the center of the diaphragm constituting one surface of the circular pump chamber, the ring-shaped area surrounded by the outer periphery of the circular piezoelectric element and the wall surface of the pump chamber is convex upward and convex downward. Operates with repeated deformation. The central part where the piezoelectric element is attached to the diaphragm is deformed downward when the ring-shaped area of the diaphragm is deformed upward, and conversely, when the ring-shaped area of the diaphragm is deformed downward. Transforms upwards convexly.

  Thus, sufficient vibration cannot be obtained in the predetermined vibration mode if there is a large deflection in the ring-shaped area. However, a large deflection may occur in the ring-shaped area due to the deformation of the initial diaphragm before assembly or the difference in the amount of thermal expansion of each component during adhesive heat curing. Even if there is no significant deflection during assembly, depending on the diaphragm material and thickness, the temperature of the piezoelectric blower may become uneven due to temperature changes in the surrounding environment during operation and the temperature rise of the piezoelectric element due to driving. Since it rises with it, a big deflection | deviation arises in the said ring-shaped area, and a pressure and a flow volume will fall.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a piezoelectric pump that can solve the problem caused by the large deflection of the diaphragm and ensure a high pressure and flow rate.

In order to solve the above-described problems, the present invention is configured as follows.
(1) A pump body is constituted by the pump main body, a diaphragm structure having an outer peripheral portion fixed to the pump main body and having a diaphragm and a piezoelectric element, and the pump main body and the diaphragm, and the piezoelectric element is driven. In the piezoelectric pump that bends and deforms the diaphragm by
The diaphragm structure includes a tension plate that applies a tensile stress to the diaphragm in a peripheral direction from a central portion of the diaphragm.

  With this configuration, it is possible to always apply tension to the diaphragm, so that no deflection occurs during assembly, and the diaphragm can be reliably vibrated in a predetermined vibration mode. In addition, even if the temperature of the piezoelectric blower rises due to temperature fluctuations in the surrounding environment or due to temperature rise of the piezoelectric element due to driving, the ring-shaped area is unlikely to bend, and pressure and flow rate are deteriorated. Few. Rather, the flow rate increases because the piezoelectric element vibrates on the tensioned diaphragm.

(2) The pump main body includes a pump chamber top plate facing the diaphragm, and a frame body that is sandwiched between the diaphragm and the pump chamber top plate to form a space,
The tension plate includes an opening and a spring portion that acts in a direction to expand and contract the inner diameter of the opening, and the tension plate is attached to the diaphragm.

  With this configuration, the diaphragm is always subjected to a constant tension by the tension plate, and even if the temperature of the piezoelectric blower rises with temperature unevenness due to the temperature change of the surrounding environment or the temperature rise of the piezoelectric element due to driving, etc. Deflection is very unlikely to occur in the ring-shaped area, and the deterioration of pressure and flow rate is extremely reduced. Therefore, it is difficult to deteriorate with time and a stable flow rate can be obtained.

(3) The frame body is formed of, for example, an elastomer molded body.
Thereby, the frame body tries to spread by the tension by the tension plate, that is, the tension by the tension plate is not blocked, so that a predetermined tension can be effectively applied to the diaphragm.

(4) A pump body is configured by the pump body, the diaphragm structure having an outer peripheral portion fixed to the pump body, the diaphragm structure having the diaphragm and the piezoelectric element, and the pump body and the diaphragm, and driving the piezoelectric element. In the piezoelectric pump that bends and deforms the diaphragm by
The diaphragm structure includes a tension plate that applies a tensile stress in the peripheral direction from the center of the diaphragm to the diaphragm,
A pump chamber top plate facing the diaphragm;
A first opening formed at a portion of the top of the pump chamber facing the central portion of the diaphragm and communicating the inside and outside of the pump chamber;
On the opposite side of the pump chamber with the pump chamber top plate in between, a top plate provided at a distance from the pump chamber top plate,
A second opening formed at a portion of the top plate facing the first opening;
An inflow passage formed between the top plate of the pump chamber and the top plate, having one end communicating with the outside of the pump chamber and the other end connected to the first opening and the second opening; Features.
This configuration further increases the flow rate and stress.

(5) The resonance frequency of the diaphragm is approximated to the natural vibration frequency of the piezoelectric element by the tension applied to the diaphragm by the tension plate.

  Thus, when the diaphragm is pulled from the central part to the peripheral direction by the tension plate, the resonance frequency is increased. By approximating this to the natural vibration frequency of the piezoelectric element, the displacement of the diaphragm is increased and a larger flow rate is obtained. Is obtained.

(6) The pump body is constituted by the pump body, the diaphragm structure having an outer peripheral portion fixed to the pump body, the diaphragm and the piezoelectric element, and the pump body and the diaphragm, and the piezoelectric element is driven. A piezoelectric pump manufacturing method for bending and deforming the diaphragm by:
A tension plate having an inner diameter larger than the inner diameter of the pump chamber and having spring structures at the four corners, and a fit-fit process with a jig so that the opening diameter is smaller;
A step of attaching the diaphragm of the diaphragm structure to the tension plate in a state where the tension plate is attached to the jig;
Removing the diaphragm structure together with the tension plate from the jig to obtain the diaphragm structure with the tension plate;
A step of joining the diaphragm structure with a tension plate and the pump chamber main body to form a pump chamber.

  By manufacturing in this way, it is possible to stably form a piezoelectric pump in which a predetermined tension is always applied to the diaphragm.

  According to the present invention, it is possible to obtain a piezoelectric pump that can solve the problem caused by the deflection of the diaphragm and ensure high pressure and flow rate.

A piezoelectric pump according to an embodiment of the present invention and a manufacturing method thereof will be described with reference to the drawings.
FIG. 2A is a cross-sectional view of the piezoelectric pump 100 of the same embodiment. FIG. 2B is a diagram illustrating the flow of fluid by the piezoelectric pump 100. Here, a configuration example of a piezoelectric pump for air cooling of an electronic device is shown.
The piezoelectric pump 100 includes a top plate 10, a channel plate 20, a pump chamber top plate 30, a frame body 40, a diaphragm 51, an intermediate plate 53, a piezoelectric element 54, and a tension plate 60. The diaphragm 51 is made of white (copper / zinc / nickel alloy). The tension plate 60 is made of beryllium copper. The frame 40 is made of EPDM (ethylene / propylene / diene rubber), and has a pump chamber diameter of 16 mm and a pump chamber height of 0.07 mm.

  The diaphragm 51, the intermediate plate 53, and the piezoelectric element 54 are thermally bonded in advance by applying a thermosetting adhesive and heating to form a diaphragm structure (50) to be described later. The member excluding the diaphragm structure 50 of the piezoelectric pump 100 is a pump body.

  The top plate 10 includes an opening hole (second opening) 11 at the center thereof, and is joined to the flow path plate 20. A plan view of the top plate 10 is shown in FIG. The top plate 10 is a flat plate having a rectangular outer shape, and is made of a rigid material such as a cold rolled steel plate (SPCC). The opening hole 11 communicates with the outside of the piezoelectric pump 100 and the flow channel central chamber 21 of the flow channel plate 20.

  The flow path plate 20 includes a flow path center chamber 21 and an inflow passage 22, and is joined to the top plate 10 and the pump chamber top plate 30. A plan view of the flow path plate 20 is shown in FIG. The flow path plate 20 is a flat plate having the same outer shape as the top plate 10 and is made of the same material as the top plate 10. A flow path central chamber 21 is formed at the center of the flow path plate 20, and four inflow passages 22 are formed from the flow path central chamber 21 to the four corners of the flat plate. The flow path center chamber 21 has a larger diameter than the opening hole 11 and communicates with the opening hole 11 and the opening hole (first opening) 31 of the pump chamber top plate 30. The inflow passage 22 communicates with the flow path central chamber 21 and the inflow hole 32 of the pump chamber top plate 30. Since the plurality of inflow passages 22 are passed through the flow path central chamber 21, the resistance in the inflow passages 22 is reduced, and the gas is drawn to the flow path central chamber 21. Therefore, the gas flow rate can be increased.

  The pump chamber top plate 30 includes an opening hole 31 and an inflow hole 32, and is joined to the flow path plate 20 and the frame body 40. A plan view of the pump chamber top plate 30 is shown in FIG. The pump chamber top plate 30 is a flat plate having the same outer shape as the flow path plate 20 and is made of the same material as the flow path plate 20. An opening hole 31 is formed at the center of the pump chamber top plate 30, and four inflow holes 32 are formed at the four corners of the flat plate. The opening hole 31 has substantially the same diameter as the opening hole 11 and communicates with the flow path center chamber 21 and the pump chamber 41 of the frame body 40. Further, the inflow hole 32 communicates with the inflow passage 22 and the inflow hole 42 of the frame body 40. The opening hole 31 may have a diameter different from that of the opening hole 11, but preferably has a diameter smaller than that of the flow path center chamber 21. Moreover, the pump chamber top plate 30 may be made of a material different from that of the flow path plate 20, and for example, it is preferable to make the pump chamber top plate 30 of a material having spring elasticity.

  The frame body 40 includes a pump chamber 41 and an inflow hole 42, and is joined to the pump chamber top plate 30 and the diaphragm 51. A plan view of the frame 40 is shown in FIG. The frame 40 is a flat plate having the same outer shape as the pump chamber top plate 30 and is made of the same material as the pump chamber top plate 30. A circular pump chamber 41 is formed at the center of the frame body 40, and four inflow holes 42 are formed at the four corners of the flat plate. The pump chamber 41 has a larger diameter than the flow channel central chamber 21 and communicates with the opening hole 31. The inflow hole 42 communicates with the inflow hole 32 and the inflow hole 52 of the diaphragm 51.

  An intermediate plate 53 and a piezoelectric element 54 are thermally bonded to the diaphragm 51. These constitute the diaphragm structure 50. FIG. 7A shows a plan view of the diaphragm structure 50, and FIG. 7B shows a cross-sectional view of the diaphragm structure 50 taken along the line AA in FIG. 7A.

  The diaphragm 51 has two cuts 55 at each of the four corners of the rectangular plate shape, and the slits 56 are formed in projecting portions that protrude relatively from the cuts. In addition, at the four corners of the diaphragm 51, there are provided inflow holes 52 respectively continuous with the slits 56.

  The diaphragm 51 is joined to the frame body 40 and the tension plate 60. The inflow hole 52 communicates with the inflow hole 32 and the inflow hole 62 of the tension plate 60. The intermediate plate 53 is a flat plate having a circular outer shape, and is thermally bonded to the central portion of the diaphragm 51. The piezoelectric element 54 is a flat plate having the same outer shape as the intermediate plate 53, and is thermally bonded to the intermediate plate 53.

  The tension plate 60 includes a circular opening 61 which is a piezoelectric element accommodation chamber and an inflow hole 62, and is joined to the diaphragm 51 of the diaphragm structure 50. A plan view of the tension plate 60 is shown in FIG. The tension plate 60 is formed with two notches 65 at each of the four corners of the rectangular plate shape, and the slits 66 are formed in projecting portions that relatively project from the notches. A circular opening 61 is formed at the center of the tension plate 60, and four inflow holes 62 are formed at the four corners of the flat plate. The slit 66 is connected to the opening 61 and the inflow hole 62 and is continuous. Thus, the notch 65 and the slit 66 constitute a spring structure.

  The opening 61 accommodates the intermediate plate 53 and the piezoelectric element 54 of the diaphragm structure 50. The inflow hole 62 communicates with the inflow hole 52. The tension plate 60 is configured to be thicker than the sum of the thickness of the intermediate plate 53, the thickness of the piezoelectric element 54, and the deformation amount of the piezoelectric element 54, and the piezoelectric element 54 is mounted when the piezoelectric pump 100 is mounted. This prevents contact with the substrate.

  Here, the diaphragm structure 50 has a unimorph structure in which the piezoelectric element 54 is provided only on one surface side of the diaphragm 51. The piezoelectric element 54 may be formed of two piezoelectric layers and have a bimorph type structure. By applying an alternating voltage (sine wave or rectangular wave) to the piezoelectric element 54, the entire diaphragm structure 50 is bent in the thickness direction. Further, as the diaphragm structure 50 is bent, the pump chamber top plate 30 resonates. As a result, the distance between the diaphragm 51 and the pump chamber top plate 30 changes, and the gas flows into or out of the pump chamber 41 from the opening hole 31.

  The alternating voltage applied to the piezoelectric element 54 is the primary resonance frequency or the tertiary resonance frequency of the diaphragm structure 50. As a result, the displacement volume of the displacement member can be remarkably increased and the flow rate can be significantly increased as compared with the case where an alternating voltage having a frequency other than the primary or tertiary resonance frequency is applied.

FIG. 9 is a schematic cross-sectional view of the main part for explaining the operation of the piezoelectric pump 100. The arrows in the figure indicate the gas flow.
FIG. 2A shows the main part when no alternating voltage is applied to the piezoelectric element. At this time, the diaphragm 51 is substantially flat.
FIG. 5B shows the main part when a quarter cycle of the alternating voltage has elapsed. At this time, since the diaphragm 51 is bent convexly downward, the distance between the diaphragm 51 and the opening hole 31 of the pump chamber top plate 30 increases, so that the gas flows from the inflow passage 22 into the pump chamber 41 through the opening hole 31. Inhaled.

  FIG. 3C shows the main part when the next quarter period has elapsed. At this time, the diaphragm 51 returns to a flat state, and the distance between the diaphragm 51 and the opening hole 31 of the pump chamber top plate 30 is reduced. For this reason, the gas in the pump chamber 41 is pushed out through the opening holes 31 and 11. The gas flowing in from the opening hole 11 is entrained by the gas in the inflow passage 22, and the gas around the opening hole 11 is also entrained outside the opening hole 11.

  FIG. 4D shows the main part when the next quarter period has elapsed. At this time, the diaphragm 51 is bent upward and the distance between the diaphragm 51 and the opening hole 31 of the pump chamber top plate 30 is reduced. For this reason, the gas in the pump chamber 41 is pushed out through the opening holes 31 and 11. The gas flowing in from the opening hole 11 is entrained by the gas in the inflow passage 22, and the gas around the opening hole 11 is also entrained outside the opening hole 11.

  FIG. 5E shows the main part when the next quarter period has elapsed. At this time, the diaphragm 51 returns to a flat state, and the distance between the diaphragm 51 and the opening hole 31 of the pump chamber top plate 30 increases. For this reason, part of the gas flowing through the inflow passage 22 is sucked into the pump chamber 41 through the opening hole 31. However, most of the gas flowing through the inflow passage 22 continues to flow out of the opening hole 11 due to inertia.

  The diaphragm 51 repeats the above deformation periodically. By increasing the distance between the diaphragm 51 and the opening hole 31 of the pump chamber top plate 30, the flow path central chamber 21, the inflow passage 22, the inflow hole 32, the inflow hole 42, the inflow hole 52, and the inflow hole 62, Gas flows into the pump chamber 41, and the distance between the diaphragm 51 and the opening hole 31 of the pump chamber top plate 30 decreases, so that the pump chamber 41, the opening hole 31, the flow path center chamber 21, and the opening hole 11 are passed through. Thus, the gas flows out of the piezoelectric pump. By oscillating the piezoelectric element at a high frequency, the gas can flow continuously from the opening hole 11 without the inertia of the gas flowing through the inflow passage 22 ending.

  According to the present invention, the diaphragm 51 shown in FIG. 2 is always pulled from the central portion to the peripheral direction by the tension plate 60, and therefore the outer peripheral portions of the piezoelectric element 54 and the intermediate plate 53 and the tension plate of the diaphragm 51. The ring-shaped area surrounded by 60 does not flex, and a diaphragm structure that vibrates in a predetermined vibration mode is obtained.

  In addition, since the tension of the tension plate can be reliably received by the diaphragm, even if the temperature of the piezoelectric blower rises due to temperature variation of the surrounding environment or the temperature of the piezoelectric element due to driving, etc. Is very unlikely to bend, and there is very little deterioration in pressure and flow rate.

  Further, since the frame body 40 is formed of an elastomer molded body, the frame body 40 tries to spread by the tension of the tension plate 60, that is, the tension by the tension plate is not blocked. Can be effectively applied.

  Further, since the tension plate 60 also serves as the bottom plate of the piezoelectric pump, it is not necessary to provide a member for applying tension to the diaphragm separately from the bottom plate, and an increase in the number of parts and an increase in size can be avoided.

  Further, since the diaphragm 51 vibrates in the same vibration mode as the membrane vibrates due to the tension, the resonance frequency of the diaphragm 51 can be set by setting the tension by the tension plate 60, and the resonance frequency is set to the piezoelectric element. By approximating the natural resonance frequency of the diaphragm, the displacement of the diaphragm is increased, and a larger flow rate is obtained.

  As the diaphragm 51 is made thinner, the propagation speed of vibration depends on the tension. For this reason, the resonance frequency of the diaphragm 51 greatly depends on the tension by the tension plate 60. However, in a design in which resonance driving is performed at a frequency of 20 kHz or more, it is necessary to make the pump chamber smaller than the piezoelectric element. As a result, the width of the ring-shaped area is narrowed, and most of the thickness of the diaphragm structure 50 cannot be said to be sufficiently thin compared with the width of the ring-shaped area, and the vibration of the ring-shaped area is caused by tension. It is not the vibration of the membrane, but rather the bending vibration of the plate. For this reason, even if there is variation in the spring tension of the tension plate 60, the resonance frequency does not deviate so much, and it can be driven at a predetermined resonance frequency of 20 kHz or more.

Next, a method for manufacturing a piezoelectric pump, particularly a method for attaching a tension plate to a diaphragm structure will be described.
FIG. 10 is a diagram illustrating a procedure for attaching the tension plate to the diaphragm structure.
FIG. 10A is a plan view of a tension plate, and FIG. 10B is a plan view of a jig for fitting the tension plate. The jig 70 includes a mounting portion 71 into which the tension plate 60 is fitted. The width of the mounting portion 71 in the front-rear and left-right directions is narrower by a predetermined dimension than the left-right and upper-lower widths of the tension plate 60.

  The predetermined dimension varies depending on the thickness, material, and the like of the tension plate, but the opening diameter of the tension plate 60 is made larger than the inner diameter of the pump chamber, and the inner diameter of the tension plate when fitted into the jig is the pump chamber. It is preferable that the inner diameter of the pump chamber is designed to be approximately the same as the inner diameter of the pump chamber, because the entire bottom surface of the pump chamber can be formed of a diaphragm structure, and the bending deformation of the diaphragm can be utilized to the maximum.

  The tension plate 60 is tightly fitted by fitting the tension plate 60 into the mounting portion 71. Thereby, the width | variety of the front and rear, right and left of the tension | tensile_strength board 60 becomes narrow only by the predetermined dimension, and the opening diameter of the opening 61 becomes small by that much.

  FIG. 10C shows a state where the tension plate 60 is fitted into the mounting portion of the jig 70. In this state, the slit 66 of the tension plate 60 is narrowed and the opening diameter of the opening 61 is reduced. That is, the formation part of the slit 66 has a spring structure, and the tension plate 60 is tightly fitted by the spring elasticity, and a compressive stress is applied to the tension plate 60.

  The depth of the mounting portion 71 of the jig 70 shown in FIG. 10B is substantially equal to the thickness of the tension plate 60. Therefore, the upper surface of the tension plate 60 is substantially flush with the upper surface of the jig 70 in the state shown in FIG.

FIG. 10D shows a state in which the diaphragm structure 50 is bonded to the tension plate 60 attached to the jig 70. After the diaphragm structure 50 is bonded to the tension plate 60 as described above, the diaphragm structure 50 is removed from the jig 70 as shown in FIG. As a result, the front, rear, left and right of the tension plate 60 are expanded, and the slit 66 is expanded to the original width, so that the opening diameter of the opening 61 is increased. Due to the expansion of the opening diameter of the opening 61, the diaphragm 51 of the diaphragm structure 50 is subjected to tensile stress from the central portion toward the peripheral direction. At that time, the gap between the slits 56 of the diaphragm 51 tends to expand, and the diaphragm 51 expands evenly in the surface direction. That is, a tensile stress is applied to the diaphragm 51 from the central portion to the peripheral direction.
In this way, the diaphragm structure 50 to which tensile stress is applied is obtained.

  According to the manufacturing method described above, tensile stress can be stably applied to the diaphragm, and the diaphragm 51 is surrounded by the outer peripheral portion of the piezoelectric element 54 and the intermediate plate 53 and the tension plate 60 during assembly. Since the ring-shaped area is reliably assembled without bending, a diaphragm structure that vibrates in a predetermined vibration mode is obtained.

  Thereafter, the diaphragm structure with a tension plate, the frame body 40, the pump chamber top plate 30, the flow channel plate 20, and the top plate 10 are joined. In this way, the piezoelectric pump is manufactured.

A specific configuration example of a piezoelectric pump used as a fuel cell cooling pump and characteristics obtained thereby will be described.
Input voltage: 16.4 kHz, rectangular wave voltage of ± 60 V to ± 90 V Diaphragm: White plate of 0.08 mm thickness Intermediate plate: SUS plate of thickness 0.2 mm, diameter 12.7 mm Piezoelectric element: thickness 0.2 mm, diameter 12 .7mm PZT plate Pump chamber: height 0.07mm, diameter 16mm
Top plate: Thickness 0.3mm, opening hole diameter 0.6mm
Tension plate: 0.8mm thick, 16.0mm inside diameter (16.4mm before fitting)
Pump chamber top: thickness 0.8mm, opening hole diameter 2.0mm
When the piezoelectric pump was driven under the above conditions, a no-load flow rate: 0.6 L / min could be obtained. As a result, it was confirmed that a piezoelectric pump with a large flow rate was obtained.

  As a comparative example, the no-load flow rate when using a bottom plate having no spring structure, the inner diameter being the same as that of the pump chamber, and the thickness being 0.8 mm was 0.3 L / min. It was.

It is sectional drawing of the gas pump shown by patent document 1. FIG. It is sectional drawing of the piezoelectric pump which concerns on embodiment of this invention. It is a top view of the top plate of the piezoelectric pump. It is a top view of the flow-path board of the same piezoelectric pump. It is a top view of the pump chamber top plate of the piezoelectric pump. It is a top view of the frame of the same piezoelectric pump. It is a figure of the diaphragm structure of the same piezoelectric pump. It is a top view of the tension plate of the same piezoelectric pump. It is a figure explaining operation | movement of the same piezoelectric pump. It is a figure which shows the attachment procedure of the tension | tensile_strength board with respect to a diaphragm structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Top plate 11 ... Opening hole 20 ... Channel plate 21 ... Channel center chamber 22 ... Fluid passage 30 ... Pump chamber top plate 31 ... Opening hole 32 ... Inflow hole 40 ... Frame body 41 ... Pump chamber 42 ... Inflow hole 50 ... Diaphragm structure 51 ... Diaphragm 52 ... Inflow holes 53 and 73 ... Intermediate plate 54 ... Piezoelectric elements 55 and 65 ... Notches 56 and 66 ... Slit 60 ... Tension plate 61 ... Opening (piezoelectric element accommodation chamber)
62 ... Inflow hole 70 ... Jig 71 ... Mounting part 100 ... Piezoelectric pump

Claims (6)

A pump body is constituted by a pump main body, a diaphragm structure having an outer peripheral portion fixed to the pump main body and having a diaphragm and a piezoelectric element, and the pump main body and the diaphragm, and the diaphragm is driven by driving the piezoelectric element. In the piezoelectric pump that bends and deforms,
2. The piezoelectric pump according to claim 1, wherein the diaphragm structure includes a tension plate that applies a tensile stress to the diaphragm in a peripheral direction from a central portion of the diaphragm. The pump body includes a pump chamber top plate facing the diaphragm, and a frame body that is sandwiched between the diaphragm and the pump chamber top plate to form a space,
2. The piezoelectric pump according to claim 1, wherein the tension plate has an opening and a spring portion that acts in a direction of expanding and contracting the inner diameter of the opening, and the tension plate is attached to the diaphragm. .   The piezoelectric pump according to claim 2, wherein the frame is an elastomer molded body. A pump body is constituted by a pump main body, a diaphragm structure having an outer peripheral portion fixed to the pump main body and having a diaphragm and a piezoelectric element, and the pump main body and the diaphragm, and the diaphragm is driven by driving the piezoelectric element. In the piezoelectric pump that bends and deforms,
The diaphragm structure includes a tension plate that applies a tensile stress in the peripheral direction from the center of the diaphragm to the diaphragm,
A pump chamber top plate facing the diaphragm;
A first opening formed at a portion of the top of the pump chamber facing the central portion of the diaphragm and communicating the inside and outside of the pump chamber;
On the opposite side of the pump chamber with the pump chamber top plate in between, a top plate provided at a distance from the pump chamber top plate,
A second opening formed at a portion of the top plate facing the first opening;
An inflow passage formed between the top plate of the pump chamber and the top plate, having one end communicating with the outside of the pump chamber and the other end connected to the first opening and the second opening; A featured piezoelectric pump.   5. The piezoelectric pump according to claim 1, wherein a resonance frequency of the diaphragm approximates a natural vibration frequency of the piezoelectric element by a tension applied to the diaphragm by the tension plate. A pump body is constituted by a pump main body, a diaphragm structure having an outer peripheral portion fixed to the pump main body and having a diaphragm and a piezoelectric element, and the pump main body and the diaphragm, and the diaphragm is driven by driving the piezoelectric element. A method of manufacturing a piezoelectric pump that bends and deforms,
A tension plate having an inner diameter larger than the inner diameter of the pump chamber and having spring structures at the four corners, and a fit-fit process with a jig so that the opening diameter is smaller;
A step of attaching the diaphragm of the diaphragm structure to the tension plate in a state where the tension plate is attached to the jig;
Removing the diaphragm structure together with the tension plate from the jig to obtain the diaphragm structure with the tension plate;
A method of manufacturing a piezoelectric pump, comprising: joining the diaphragm structure with a tension plate and the pump chamber body to form a pump chamber.

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