JP6575634B2 - Blower - Google Patents

Description

  The present invention relates to a blower for conveying a fluid.

  Conventionally, various valves that make a fluid flow in one direction have been disclosed. For example, Patent Document 1 discloses a valve 910 that includes two plates 914 and 916 that are close to each other and a flap 917 that is sandwiched between the two plates 914 and 916 as shown in FIG. An arrow 932 in FIG. 19 indicates the flow of air.

  The plate 916 is provided with a plurality of vent holes 920. The plate 914 is provided with a plurality of ventilation holes 918. Further, the plate 914 is provided with a plurality of auxiliary holes 928. The auxiliary hole 928 has the same shape as the vent hole 920. The plurality of vent holes 918 and the plurality of auxiliary holes 928 communicate with a suction hole of a pump (not shown).

  The valve 910 opens and closes the vent hole 920 by pulling the flap 917 toward the plate 914 or the plate 916 by wind generated by the pump. Thereby, the valve 910 makes the air flow in one direction.

  Here, the auxiliary hole 928 is provided in order to accelerate the flap 917 and promote opening and closing of the vent hole 920.

Special table 2012-528981

  However, in the valve 910 of Patent Document 1, when the two plates 914 and 916 are bonded together with the flap 917 interposed therebetween, there is a possibility that a positional deviation occurs. When the positional deviation occurs, the flow path resistance increases and the flow rate of the air passing through the valve 910 decreases.

  Therefore, a method of inspecting the positional deviation visually from the vent hole 920 when the plate 916 is viewed from the front is conceivable. However, as shown in FIG. 19, the auxiliary hole 928 has the same shape as the vent hole 920. Therefore, the manufacturer cannot see the outer periphery of the auxiliary hole 928 from the vent hole 920. Therefore, it is difficult for the valve 910 of Patent Document 1 to inspect the positional deviation between the two plates 914 and 916 sandwiching the flap 917 (movable plate).

  SUMMARY OF THE INVENTION An object of the present invention is to provide a valve and a fluid control device that can easily inspect a positional deviation between two plates sandwiching a movable plate.

  The present invention relates to an actuator having a diaphragm having a first main surface and a second main surface, a driving body for bending and vibrating the diaphragm, and the diaphragm from the thickness direction of the diaphragm together with the actuator. A blower having a first blower chamber and a second blower chamber sandwiched therebetween, wherein the diaphragm has a plurality of openings arranged in an annular shape, and the casing includes the first blower chamber and the second blower chamber. The first blower chamber communicates with the outside of the casing and a discharge hole having a discharge valve for preventing fluid from flowing into the first blower chamber from the outside; and the second blower chamber communicates with the outside of the casing. And a suction hole having a suction valve for preventing fluid from flowing out of the blower chamber.

  Moreover, in the blower of this invention, the said housing has the said discharge hole and the said suction hole in the part which overlaps with the said drive body by seeing the said 1st main surface of the said diaphragm in front.

  In the blower of the present invention, the suction valve is closed when the discharge valve is closed, and the suction valve is opened when the discharge valve is opened.

  In the blower of the present invention, the diaphragm includes a vibrating body, an outer peripheral portion, and a beam portion that is disposed between the vibrating body and the outer peripheral portion and forms the plurality of openings together with the vibrating body and the outer peripheral portion. And an inner space surrounded by the plurality of openings constitutes the first blower chamber.

  According to the present invention, the suction pressure and the suction flow rate can be increased.

It is an external appearance perspective view of the fluid control apparatus 111 seen from the top | upper surface side of the fluid control apparatus 111 which concerns on the 1st Embodiment of this invention. FIG. 2 is an external perspective view of the fluid control device 111 viewed from the bottom side of the fluid control device 111 shown in FIG. 1. It is a disassembled perspective view of the fluid control apparatus 111 shown in FIG. It is a front view of the center part of the top plate 21 shown in FIG. It is a front view of the center part of the movable plate 24 shown in FIG. It is a front view of the center part of the baseplate 23 shown in FIG. It is a front view of the center part of the valve | bulb 12 which joined the top plate 21, the movable plate 24, and the bottom plate 23 which were shown in FIG. It is sectional drawing in the SS line | wire shown in FIG. It is sectional drawing of the SS line | wire of the fluid control apparatus 111 when the fluid control apparatus 111 shown in FIG. 1 is operated by the frequency (fundamental wave) of a primary mode. FIG. 10 is an enlarged cross-sectional view showing the air flow around the auxiliary hole 49 at the moment shown in FIG. It is a front view of the center part of the baseplate 223 with which the fluid control apparatus 211 which concerns on the 2nd Embodiment of this invention is equipped. FIG. 12 is a front view of a central portion of a valve 212 to which a top plate 21, a movable plate 24 and a bottom plate 223 shown in FIG. 11 are joined. FIG. 12 is an enlarged cross-sectional view showing the air flow around the auxiliary hole 249 while the piezoelectric blower 13 provided in the fluid control device 211 shown in FIG. 11 is driven. It is an external appearance perspective view of the fluid control apparatus 311 which concerns on 3rd Embodiment of this invention. It is an external appearance perspective view of the fluid control apparatus 311 shown in FIG. FIG. 15 is an external perspective view of a diaphragm 141 and a piezoelectric element 47 shown in FIG. 14. It is sectional drawing in the UU line shown in FIG. FIG. 15 is a cross-sectional view taken along the line U-U of the fluid control device 311 when the fluid control device 311 shown in FIG. 14 is operated at a primary mode frequency (fundamental wave). It is sectional drawing of the valve | bulb 910 which concerns on patent document 1. FIG.

<< First Embodiment >>
Hereinafter, the fluid control apparatus 111 according to the first embodiment of the present invention will be described.

  FIG. 1 is an external perspective view of the fluid control device 111 viewed from the top side of the fluid control device 111 according to the first embodiment of the present invention. 2 is an external perspective view of the fluid control device 111 viewed from the bottom side of the fluid control device 111 shown in FIG. 3 is an exploded perspective view of the fluid control device 111 shown in FIG. FIG. 4 is a front view of the central portion of the top plate 21 shown in FIG. FIG. 5 is a front view of the central portion of the movable plate 24 shown in FIG. 6 is a front view of the central portion of the bottom plate 23 shown in FIG. FIG. 7 is a front view of the central portion of the valve 12 in which the top plate 21, the movable plate 24, and the bottom plate 23 shown in FIG. 3 are joined. 8 is a cross-sectional view taken along the line SS shown in FIG.

  As shown in FIGS. 1 to 3, the fluid control device 111 includes a valve 12, a piezoelectric blower 13, and a control unit 14 (see FIG. 8). As shown in FIGS. 1 and 3, the valve 12 is arranged on the top surface side of the fluid control device 111. As shown in FIGS. 2 and 3, the piezoelectric blower 13 is disposed on the bottom surface side of the fluid control device 111. The valve 12 and the piezoelectric blower 13 are pasted together in a stacked state.

  The valve 12 has a function of making the fluid flow in one direction. The valve 12 has a cylindrical container shape in which a valve chamber 40 is provided. As shown in FIGS. 1 and 3, the valve 12 includes a top plate 21, a side wall plate 22, a bottom plate 23, and a movable plate 24.

  The valve 12 corresponds to an example of the valve of the present invention. The piezoelectric blower 13 corresponds to an example of the blower of the present invention. The top plate 21 corresponds to an example of the first plate of the present invention. The bottom plate 23 corresponds to an example of the second plate of the present invention.

  The top plate 21, the side wall plate 22, and the bottom plate 23 are made of metal. The top plate 21, the side wall plate 22, and the bottom plate 23 are made of, for example, stainless steel (SUS).

  The movable plate 24 is made of resin. Here, the movable plate 24 is preferably transparent. The movable plate 24 is made of, for example, translucent polyimide.

  The top plate 21 is disposed on the top surface side of the bulb 12. The side wall plate 22 is provided between the top plate 21 and the bottom plate 23. The bottom plate 23 is provided on the bottom surface side of the valve 12. The top plate 21, the side wall plate 22, and the bottom plate 23 are pasted together in a stacked state. The movable plate 24 is provided in the internal space of the valve 12, that is, in the valve chamber 40.

  The top plate 21 has a disk shape. The side wall plate 22 has an annular shape when viewed from the top surface side. The bottom plate 23 has a disk shape. The outer peripheral diameters of the top plate 21, the side wall plate 22, and the bottom plate 23 coincide with each other.

  The valve chamber 40 is cylindrical. The valve chamber 40 is provided in the center of the side wall plate 22 with a predetermined diameter. The movable plate 24 has a substantially disk shape when viewed from the top side. The movable plate 24 is set to a thickness thinner than the thickness of the side wall plate 22.

  In the present embodiment, the thickness of the side wall plate 22 (height of the valve chamber 40) is 40 μm or more and 50 μm or less, and the thickness of the movable plate 24 is set to 5 μm or more and 10 μm or less. The movable plate 24 is set to an extremely light mass so as to be movable up and down inside the valve chamber 40 by the discharge air from the piezoelectric blower 13.

  The outer peripheral diameter of the movable plate 24 almost coincides with the opening diameter of the valve chamber 40 in the side wall plate 22, and is set to be small and small so that a slight gap is left. And the protrusion part 25 is provided in a part of outer periphery of the movable plate 24 (refer FIG. 3).

  Further, a cutout portion 26 into which the protruding portion 25 is fitted with a minute gap is provided on a part of the inner periphery of the side wall plate 22 (see FIG. 3). For this reason, the movable plate 24 is held in the valve chamber 40 so as not to rotate but to move up and down.

  In the center of the top plate 21, a plurality of first vent holes 41 arranged in a predetermined arrangement are provided. A plurality of second ventilation holes 43 and a plurality of auxiliary holes 49 arranged in a predetermined arrangement are provided in the center of the bottom plate 23. A plurality of third ventilation holes 42 arranged in a predetermined arrangement are provided in the center of the movable plate 24. Accordingly, the valve chamber 40 communicates with the outside through the first vent hole 41 and also communicates with the blower chamber 45 through the second vent hole 43.

  Here, the plurality of first ventilation holes 41 and the plurality of second ventilation holes 43 are arranged so as not to face each other. The plurality of auxiliary holes 49 and the plurality of first ventilation holes 41 are arranged to face each other. Each auxiliary hole 49 overlaps with each first vent hole 41 when the main surface of the top plate 21 opposite to the valve chamber 40 is viewed from the front. Further, the center axis of each auxiliary hole 49 and the center axis of each first vent hole 41 coincide.

  Further, the plurality of third ventilation holes 42 and the plurality of first ventilation holes 41 are arranged so as not to face each other. The plurality of third ventilation holes 42 and the plurality of auxiliary holes 49 are arranged so as not to face each other. The plurality of third ventilation holes 42 and the plurality of second ventilation holes 43 are arranged so as to face each other.

  Moreover, the baseplate 23 has the some edge part 50, as shown in FIG. Each edge 50 surrounds each auxiliary hole 49. Each edge 50 overlaps each first vent hole 41 when the main surface of the top plate 21 opposite to the valve chamber 40 is viewed from the front.

  Next, the piezoelectric blower 13 is a kind of pump using a vibrating body 36 that bends and deforms when a voltage is applied to the piezoelectric element 33. As shown in FIGS. 2 and 3, the piezoelectric blower 13 has a cylindrical container shape in which a blower chamber 45 is provided.

  The piezoelectric blower 13 includes a vibration adjustment plate 54, a side wall plate 31, a vibration plate 32, and a piezoelectric element 33. The vibration adjustment plate 54, the side wall plate 31, and the vibration plate 32 are made of metal. The vibration adjustment plate 54, the side wall plate 31, and the vibration plate 32 are made of, for example, stainless steel.

  The side wall plate 31 is disposed between the bottom plate 23 and the diaphragm 32. The diaphragm 32 is disposed between the side wall plate 31 and the piezoelectric element 33. The piezoelectric element 33 is disposed on the bottom surface side of the piezoelectric blower 13. The side wall plate 31 is stuck on the bottom surface of the bottom plate 23 in a laminated state. Further, the side wall plate 31, the vibration plate 32, and the piezoelectric element 33 are pasted in a stacked state.

  The vibration adjustment plate 54 is provided for adjusting the vibration region of the bottom plate 23. Specifically, the vibration adjustment plate 54 is stuck in a state of being disposed between the bottom plate 23 and the side wall plate 31. The vibration adjustment plate 54 has an annular shape when viewed from the top side.

  In the center of the vibration adjusting plate 54, a blower upper chamber 55 is provided with a predetermined opening diameter. The blower upper chamber 55 has a smaller opening diameter than the blower lower chamber 48. The blower upper chamber 55 and the blower lower chamber 48 constitute a blower chamber 45. The vibrating body 36 is formed so that the blower chamber 45 has a radius a. Further, the vibration adjusting plate 54 and the side wall plate 31 have the same outer peripheral diameter.

  In addition, by providing the vibration adjusting plate 54 on the bottom plate 23, the rigidity can be partially increased in the vicinity of the outer peripheral portion of the bottom plate 23. As a result, the bottom plate 23 can be vibrated only in the vicinity of the central portion facing the blower upper chamber 55, and almost no vibration can be generated in the vicinity of the outer peripheral portion of the bottom plate 23.

  Therefore, the range in which the vibration of the bottom plate 23 occurs can be set by the opening diameter of the blower upper chamber 55 in the vibration adjustment plate 54. Thereby, the vibration region and the structural resonance frequency of the bottom plate 23 can be easily adjusted without changing the plate thickness, the outer peripheral diameter, or the like of the bottom plate 23.

  Since the vibration near the center of the bottom plate 23 mainly contributes to the fluid vibration and the vibration of the movable plate 24, the response of the valve 12 can be improved even if the vicinity of the outer periphery of the bottom plate 23 does not vibrate. The effect of increasing the suction flow rate can be sufficiently obtained.

  The side wall plate 31 is annular when viewed from the top side. A blower lower chamber 48 is provided in the center of the side wall plate 31 with a predetermined opening diameter.

  The diaphragm 32 includes an outer peripheral portion 34, a plurality of beam portions 35, and a vibrating body 36. The outer peripheral portion 34 has an annular shape. The vibrating body 36 has a disk shape. The vibrating body 36 is disposed in the opening of the outer circumferential portion 34 with a gap between the vibrating body 36 and the outer circumferential portion 34. The plurality of beam portions 35 are provided in a gap between the outer peripheral portion 34 and the vibrating body 36, extend along the circumferential direction of the diaphragm 32, and connect the vibrating body 36 and the outer peripheral portion 34.

  Therefore, the vibrating body 36 is supported hollowly via the beam portion 35 and can move up and down in the thickness direction. A gap (opening) between the outer peripheral portion 34 and the vibrating body 36 is provided as a suction hole 46.

  The outer peripheral portion 34 of the side wall plate 31 and the diaphragm 32 have the same outer peripheral diameter and opening diameter. The outer peripheral diameters of the side wall plate 31 and the diaphragm 32 are set smaller than the outer peripheral diameter of the valve 12 by a certain dimension.

  The piezoelectric element 33 has a disk shape having a smaller radius than the vibrating body 36 when viewed from the top surface side. The piezoelectric element 33 is attached to the bottom surface of the vibrating body 36. The piezoelectric element 33 is made of, for example, lead zirconate titanate ceramic. Since the piezoelectric element 33 is composed of a piezoelectric material, it has excellent responsiveness. Therefore, the piezoelectric element 33 can realize high frequency driving.

  Electrodes (not shown) are formed on both main surfaces of the piezoelectric element 33, and a drive voltage is applied from the control unit 14 via these electrodes. The piezoelectric element 33 has piezoelectricity that expands and contracts in the surface direction in accordance with the applied driving voltage.

  Therefore, when a driving voltage is applied to the piezoelectric element 33, the piezoelectric element 33 expands and contracts in the surface direction, and concentric bending vibrations are generated in the vibrating body 36. Due to this bending vibration, vibration is also generated in the beam portion 35 that elastically supports the vibrating body 36, and thus the vibrating body 36 vibrates so as to be displaced vertically. Thus, the piezoelectric element 33 and the vibrating body 36 constitute an actuator 37 and vibrate integrally.

  The control unit 14 is configured by a microcomputer, for example. In this embodiment, the control unit 14 adjusts the drive frequency of the piezoelectric element 33 to the resonance frequency of the blower chamber 45. The resonance frequency of the blower chamber 45 is the pressure vibration generated at the center of the blower chamber 45 and the pressure vibration that propagates and reflects to the outer peripheral side of the pressure vibration and reaches the center of the blower chamber 45 again. The frequency at which resonance occurs.

  When adjusted in this way, the vicinity of the central portion in the planar direction becomes an antinode of bending vibration, and the vicinity of the outer peripheral portion in the planar direction becomes a node of bending vibration. That is, in the blower chamber 45, a standing wave-like pressure distribution is generated in the plane direction.

  As a result, in the vicinity of the second vent hole 43 provided facing the central portion of the blower chamber 45 in the planar direction, the pressure fluctuation of the fluid increases, and the blower chamber 45 faces the outer peripheral portion of the blower chamber 45 in the planar direction. In the vicinity of the suction hole 46 provided, there is almost no fluid pressure fluctuation.

  Therefore, if the suction hole 46 is communicated with the outer peripheral portion of the blower chamber 45 in the plane direction, pressure loss through the suction hole 46 hardly occurs even if a valve or the like is not provided in the suction hole 46. Accordingly, the suction hole 46 can have any shape and size, and the flow rate of fluid can be greatly increased.

  The piezoelectric element 33 corresponds to an example of the driving body of the present invention. The bottom plate 23, the vibration adjustment plate 54, and the side wall plate 31 constitute an example of the housing of the present invention.

  Next, the air flow of the fluid control device 111 while the piezoelectric blower 13 is driven will be described.

  FIG. 9 is a side sectional view showing the air flow of the fluid control device 111 while the piezoelectric blower 13 shown in FIG. 1 is being driven. FIG. 10 is an enlarged cross-sectional view showing the air flow around the auxiliary hole 49 at the moment shown in FIG. The arrows shown in FIGS. 9 and 10 indicate the flow of air.

  In the state shown in FIG. 8, when the control unit 14 applies an AC driving voltage having a primary mode frequency (fundamental wave) to the electrodes on both principal surfaces of the piezoelectric element 33, the piezoelectric element 33 expands and contracts, and the vibrating body 36 is moved to 1. Bend and vibrate concentrically at the resonance frequency f of the next mode. As a result, as shown in FIGS. 9A and 9B, the actuator 37 is bent and deformed, and the volume of the blower chamber 45 periodically changes.

  The radius a of the blower chamber 45 and the resonance frequency f of the vibrating body 36 are values that satisfy the relationship of the first type Bessel function J0 (k0) = 0, where c is the sound velocity of the air passing through the blower chamber 131. Then, the relationship of 0.8 × (k0c) / (2π) ≦ af ≦ 1.2 × (k0c) / (2π) is satisfied.

  In the present embodiment, the resonance frequency f is 21 kHz. The sound velocity c of air is 340 m / s. k0 is 2.40. The first type Bessel function J0 (x) is expressed by the following mathematical formula.

  The pressure change distribution u (r) at each point in the blower chamber 45 is expressed by the equation u (r) = J0 (k0r / a), where r is the distance from the central axis C of the blower chamber 45. The

  As shown in FIG. 9A, when the vibrating body 36 bends to the bottom surface side, the pressure in the blower chamber 45 decreases, and the movable plate 24 is drawn toward the bottom plate 23 in the valve chamber 40 to the bottom plate 23. Contact.

  Thereby, the movable plate 24 opens the first ventilation hole 41. Therefore, external air is sucked into the valve chamber 40 through the first vent hole 41 and sucked into the blower chamber 45 through the third vent hole 42 and the second vent hole 43.

  Further, as shown in FIG. 9B, when the vibrating body 36 bends to the top surface side, the pressure in the blower chamber 45 increases, and the discharge air flows from the second vent hole 43 toward the valve chamber 40. Arise. Due to this discharge air, the movable plate 24 is pushed to the top surface side and comes into contact with the top plate 21.

  Thereby, the movable plate 24 closes the first vent hole 41. Therefore, the air in the blower chamber 45 is sucked into the valve chamber 40 through the second vent hole 43, but the flow of air from the valve chamber 40 to the outside is blocked.

  Further, in the valve 12, the vibration of the actuator 37 directly propagates from the piezoelectric blower 13 or indirectly through the air, and thus the top plate 21 is vibrated.

  Thereby, the top plate 21 is also elastically deformed so as to move up and down in the thickness direction. As shown in FIG. 9B, when the actuator 37 is bent toward the top surface and the air in the blower chamber 45 is discharged from the second vent hole 43 to the valve chamber 40, the top plate 21 is similar to the actuator 37. Bend to the top side. Thereby, the volume of the valve chamber 40 increases.

  On the other hand, as shown in FIG. 9A, when the actuator 37 bends to the bottom side, the top plate 21 bends to the bottom side due to the reaction from the state shown in FIG. 9B. Thereby, the volume of the valve chamber 40 is reduced.

  Therefore, the moving distance and the moving time when the movable plate 24 is pulled toward the bottom surface in the valve chamber 40 are shortened. As a result, the movable plate 24 can follow fluctuations in air pressure, and the valve 12 becomes highly responsive.

  Note that the vibration of the actuator 37 may be directly propagated from the piezoelectric blower 13 or indirectly through the air to vibrate the bottom plate 23.

  When af = (k0c) / (2π), the vibration node F of the vibrating body 36 coincides with the pressure vibration node of the blower chamber 131, and pressure resonance occurs. Further, even when the relationship of 0.8 × (k0c) / (2π) ≦ af ≦ 1.2 × (k0c) / (2π) is satisfied, the vibration node F of the vibrating body 36 causes the pressure vibration of the blower chamber 45 to be It almost matches the clause of

  The piezoelectric blower 13 is used for the purpose of sucking a high-viscosity liquid such as a runny nose or sputum, for example. In order to prevent the piezoelectric element from being damaged due to long-term driving, the vibration speed of the piezoelectric element needs to be 2 m / s or less. Since suction of a runny nose and sputum requires a pressure of 20 kPa or more, the piezoelectric blower 13 needs a pressure amplitude of 10 kPa / (m / s) or more. The pressure amplitude is maximum when af is 130 m / s. Even if it deviates ± 20% from there, the pressure amplitude is 10 kPa / (m / s) or more.

  Therefore, when the relationship of 0.8 × (k0c) / (2π) ≦ af ≦ 1.2 × (k0c) / (2π) is satisfied, the piezoelectric blower 13 sucks a highly viscous liquid such as a runny nose or sputum. A high suction pressure and a high suction flow rate that can be used for the application can be realized.

  Here, while the piezoelectric blower 13 is driven, at the moment shown in FIG. 9A, as shown in FIG. 10, the region of the movable plate 24 facing the first ventilation hole 41 is the first ventilation hole. The suction air from 41 to the valve chamber 40 is deformed toward the auxiliary hole 49 side. As a result, the gap h between the top plate 21 and the movable plate 24 is increased. That is, as compared with the case where the bottom plate 23 does not have the auxiliary hole 49, the flow path resistance of the valve 12 is reduced, and the air flow rate is increased.

  Therefore, according to the valve 12 of the fluid control device 111, the flow rate of the air sucked into the piezoelectric blower 13 can be allowed to pass without being reduced as much as possible. Therefore, as shown in FIG. 7, it is necessary to precisely align the four first vent holes 41 of the top plate 21 and the four auxiliary holes 49 of the bottom plate 23 so as not to be displaced in the X direction or the Y direction.

  Therefore, in the valve 12, the bottom plate 23 overlaps with the first vent hole 41 and surrounds the auxiliary hole 49 when the main surface of the top plate 21 opposite to the valve chamber 40 is viewed from the front, as shown in FIG. Part 50. The movable plate 24 is transparent.

  Therefore, when the top plate 21 and the bottom plate 23 are bonded together with the movable plate 24 interposed therebetween, the manufacturer looks into the edge portion 50 from the four first ventilation holes 41 of the top plate 21 and does not shift in the X direction or the Y direction. Thus, the positions of the four auxiliary holes 49 can be finely adjusted. That is, the manufacturer can easily align the top plate 21 and the bottom plate 23.

  Therefore, according to the valve 12 of the fluid control device 111, it is possible to easily inspect the positional deviation between the top plate 21 and the bottom plate 23 with the movable plate 24 interposed therebetween.

  In the above embodiment, the movable plate 24 is transparent, but is not limited thereto. Even when the movable plate 24 is not transparent at the time of implementation, the manufacturer can radiate ultrasonic waves or the like from the side opposite to the valve chamber 40 of the top plate 21 so that the manufacturer does not shift in the X direction or the Y direction. The position of the auxiliary hole 49 can be finely adjusted.

<< Second Embodiment >>
Next, a fluid control device 211 according to a second embodiment of the present invention will be described.

  FIG. 11 is a front view of the central portion of the bottom plate 223 provided in the fluid control device 211 according to the second embodiment of the present invention. FIG. 12 is a front view of the central portion of the valve 212 to which the top plate 21, the movable plate 24, and the bottom plate 223 shown in FIG. 11 are joined. FIG. 13 is an enlarged cross-sectional view showing the air flow around the auxiliary hole 249 while the piezoelectric blower 13 provided in the fluid control device 211 shown in FIG. 11 is being driven. The arrows shown in FIG. 13 indicate the air flow.

  The difference between the fluid control device 211 and the fluid control device 111 is that the bottom plate 223 has crosspieces 248X and 248Y that separate the auxiliary holes 249. Since the other points are the same, the description is omitted.

  Also in this configuration, while the piezoelectric blower 13 is being driven, the region of the movable plate 24 that faces the first vent hole 41 does not attract the suction air from the first vent hole 41 to the valve chamber 40 as shown in FIG. Thus, the auxiliary hole 249 is deformed. As a result, the gap h between the top plate 21 and the movable plate 24 is increased. That is, compared with the case where the bottom plate 223 does not have the auxiliary hole 249, the flow path resistance of the valve 212 is reduced, and the air flow rate is increased.

  Therefore, according to the valve 212 of the fluid control device 211, the flow rate of the air sucked from the piezoelectric blower 13 can be allowed to pass without being reduced as much as possible. Therefore, as shown in FIG. 12, it is necessary to precisely align the four first vent holes 41 of the top plate 21 and the eight auxiliary holes 249 of the bottom plate 223 so that they do not shift in the X direction or the Y direction.

  Therefore, in the valve 212, as shown in FIG. 7, the bottom plate 223 overlaps with the first vent hole 41 when viewed from the front side opposite to the valve chamber 40 of the top plate 21, and surrounds the auxiliary hole 249. Part 250. The edge portion 250 includes crosspieces 248X and 248Y that separate the auxiliary holes 249. The movable plate 24 is transparent.

  Therefore, when the top plate 21 and the bottom plate 223 are bonded to each other with the movable plate 24 interposed therebetween, the manufacturer looks into the crosspieces 248X and 248Y (part of the edge portion 250) from the four first vent holes 41 of the top plate 21. Thus, the positions of the eight auxiliary holes 249 can be finely adjusted so as not to shift in the X direction or the Y direction. That is, the manufacturer can easily align the top plate 21 and the bottom plate 223.

  Therefore, according to the fluid control device 211 and the valve 212, the positional deviation between the top plate 21 and the bottom plate 223 sandwiching the movable plate 24 can be easily inspected.

  In the above embodiment, the movable plate 24 is transparent, but is not limited thereto. Even when the movable plate 24 is not transparent at the time of implementation, the manufacturer can prevent the deviation in the X direction or the Y direction by irradiating ultrasonic waves or the like from the side opposite to the valve chamber 40 of the top plate 21. The position of the auxiliary hole 249 can be finely adjusted.

  Further, in this configuration, since there is a crosspiece 248 between each auxiliary hole 249, the movable plate 24 contacts the crosspiece 248 as shown in FIG. Therefore, the crosspiece 248 suppresses deformation of the movable plate 24. Therefore, it is possible to prevent the movable plate 24 from being damaged when the suction air suddenly increases. Thereby, durability of the valve 212 and the fluid control device 211 is improved.

<< Third Embodiment >>
Hereinafter, a fluid control device 311 according to a third embodiment of the present invention will be described.

  FIG. 14 is an external perspective view of a fluid control device 311 according to the third embodiment of the present invention. FIG. 15 is an external perspective view of the fluid control device 311 shown in FIG. FIG. 16 is an external perspective view of the diaphragm 141 and the piezoelectric element 47 shown in FIG. 15 and 16 are views seen from the bottom side of the fluid control device 311. FIG. 17 is a cross-sectional view taken along the line U-U of the fluid control device 311 shown in FIG. 18 is a cross-sectional view taken along the line U-U of the fluid control device 311 when the fluid control device 311 shown in FIG. 14 is operated at the frequency (fundamental wave) of the primary mode.

  The main difference between the fluid control device 311 and the fluid control device 111 is that the above-described valve 12 is mounted in the suction hole 324 of the piezoelectric blower 300.

  First, the fluid control device 311 includes a piezoelectric blower 300, a discharge valve 80, and a valve 12 corresponding to a suction valve. The discharge valve 80 is mounted in the discharge hole 124 of the piezoelectric blower 300. The valve 12 is mounted in the suction hole 324 of the piezoelectric blower 300. All the second ventilation holes 43 of the valve 12 communicate with the suction holes 324 of the piezoelectric blower 300.

  The piezoelectric blower 300 includes a housing 17, a diaphragm 141, a piezoelectric element 47, and a housing 317 in order from the top, and has a structure in which these are stacked in order.

  In this embodiment, the piezoelectric element 47 corresponds to the “driving body” of the present invention.

  The diaphragm 141 has a disc shape and is made of, for example, stainless steel (SUS). For example, the thickness of the diaphragm 141 is 0.6 mm. For example, the diameter of the discharge hole 124 is 0.6 mm.

  The diaphragm 141 has the same shape as the diaphragm 32 described above, as shown in FIG. The vibration plate 141 includes an outer peripheral portion 134, a plurality of beam portions 135, and a vibration body 136, similarly to the vibration plate 32 described above. The diaphragm 141 has an opening 62. The opening 62 is formed over substantially the entire circumference of the vibration plate 141 so as to surround the vibration member 136.

  Here, the outer peripheral portion 134 has an annular shape. The vibrating body 136 has a disk shape. The vibrating body 136 is disposed in the opening of the outer circumferential portion 134 with a gap between the vibrating body 136 and the outer circumferential portion 134. The plurality of beam portions 135 are provided in a gap between the outer peripheral portion 134 and the vibrating body 136, extend along the circumferential direction of the vibration plate 141, and connect the vibrating body 136 and the outer peripheral portion 134.

  Therefore, the vibrating body 136 is supported hollowly via the beam portion 135 and can move up and down in the thickness direction.

  The diaphragm 141 has a first main surface 141A and a second main surface 141B. The second main surface 141 </ b> B of the vibration plate 141 is joined to the tip of the housing 17. Thus, the diaphragm 141 forms a cylindrical blower chamber 131 with the vibrating body 136 sandwiched from the thickness direction of the vibrating body 136 together with the casing 17. The diaphragm 141 and the housing 17 are formed so that the blower chamber 131 has a radius a. For example, in the present embodiment, the radius a of the blower chamber 131 is 6.1 mm.

  The blower chamber 131 is a space inside the openings 62 (more precisely, a space inside the ring formed by connecting all the openings 62) when the second main surface 141B of the diaphragm 141 is viewed from the front. ). Therefore, a region inside the opening 62 on the second main surface 141B of the vibration plate 141 (more precisely, a region inside the ring formed by connecting all the openings 62) is the bottom surface of the blower chamber 131. Configure. The vibration plate 141 is formed, for example, by punching a metal plate.

  The piezoelectric element 47 has a disk shape, and is made of, for example, lead zirconate titanate ceramic. Electrodes are formed on both main surfaces of the piezoelectric element 47. The piezoelectric element 47 is joined to the first main surface 141A on the opposite side to the blower chamber 131 of the vibration plate 141, and expands and contracts according to the applied AC voltage. The piezoelectric element 47 and the vibrating body 136 constitute an actuator 70.

  The housing 17 is formed in a U-shaped cross section with an opening at the bottom. The tip of the housing 17 is joined to the vibration plate 141. The casing 17 is made of, for example, metal.

  The housing 17 includes a disk-shaped top plate portion 18 that faces the second main surface 141 </ b> B of the vibration plate 141, and an annular side wall portion 19 that is connected to the top plate portion 18. A part of the top plate portion 18 constitutes the top surface of the blower chamber 131.

  In this embodiment, the blower chamber 131 corresponds to the “first blower chamber” of the present invention.

  The top plate 18 has a cylindrical discharge hole 124 that allows the center of the blower chamber 131 to communicate with the outside of the blower chamber 131. The central portion of the blower chamber 131 is a portion overlapping the piezoelectric element 47 when the first main surface 141A of the vibration plate 141 is viewed from the front. The top plate portion 18 is provided with a discharge valve 80 that prevents gas from flowing from the outside of the blower chamber 131 to the inside through the discharge hole 124.

  Next, the housing 317 is formed in a U-shaped cross-section with an upper opening. The tip of the housing 317 is joined to the first main surface 141A of the vibration plate 141. The housing 317 is made of metal, for example.

  As a result, the housing 317 forms a cylindrical blower chamber 331 by sandwiching the vibrating body 136 from the thickness direction of the vibrating body 136 together with the actuator 70. The diaphragm 141 and the housing 317 are formed so that the blower chamber 331 has a radius a. That is, the blower chamber 331 has the same radius a as the blower chamber 131.

  In the present embodiment, the opening 62 of the diaphragm 141 causes the outer periphery of the blower chamber 131 to communicate with the outer periphery of the blower chamber 331. The opening 62 is formed over substantially the entire circumference of the diaphragm 141 so as to surround the blower chamber 331. Therefore, the area inside the opening 62 on the suction hole 324 side surface of the actuator 70 (more precisely, the area inside the ring formed by connecting all the openings 62) is the bottom surface of the blower chamber 331. Configure.

  The housing 317 includes a disk-shaped top plate portion 318 facing the first main surface 141A of the vibration plate 141, and an annular side wall portion 319 connected to the top plate portion 318. A part of the top plate portion 318 constitutes the top surface of the blower chamber 331.

  In this embodiment, the housing 17 and the housing 317 constitute the “housing” of the present invention. The blower chamber 131 corresponds to the “first blower chamber” of the present invention, and the blower chamber 331 corresponds to the “second blower chamber” of the present invention.

  The top plate portion 318 has a columnar suction hole 324 that communicates the center of the blower chamber 331 with the outside of the housing 317. The central portion of the blower chamber 331 is a portion that overlaps the piezoelectric element 47 when the first main surface 141A of the vibration plate 141 is viewed from the front. For example, the diameter of the suction hole 324 is 0.6 mm.

  Hereinafter, the air flow during the operation of the fluid control device 311 will be described.

  18 is a cross-sectional view of the fluid control device 311 taken along the line U-U when the fluid control device 311 shown in FIG. 13 is operated at the frequency (fundamental wave) of the primary mode. FIG. 18A is a diagram when the volume of the blower chamber 131 is the largest and the volume of the blower chamber 331 is the smallest. FIG. 18B is a diagram where the volume of the blower chamber 131 is the smallest and the blower It is a figure when the volume of the chamber 331 increases most. Here, the arrows in the figure indicate the flow of air.

  In the state shown in FIG. 17, when an AC drive voltage having a primary mode frequency (fundamental wave) is applied to the electrodes on both principal surfaces of the piezoelectric element 47, the piezoelectric element 47 expands and contracts, causing the vibrating body 136 to move to the primary. Bend and vibrate concentrically at the mode resonance frequency f.

  At the same time, the top plate 18 is concentric in the primary mode with the bending vibration of the actuator 70 (in this embodiment, the vibration phase is delayed by 180 °) due to the pressure fluctuation of the blower chamber 131 accompanying the bending vibration of the actuator 70. Bends and vibrates.

  The top plate portion 318 is also bent concentrically in the primary mode with the bending vibration of the actuator 70 (in this embodiment, the vibration phase is delayed by 180 °) due to the pressure fluctuation of the blower chamber 331 accompanying the bending vibration of the actuator 70. Vibrate.

  Thereby, as shown to FIG. 18 (A) (B), the volume of the blower chambers 131 and 331 changes periodically.

  The radius a of the blower chamber 131 and the resonance frequency f of the diaphragm 141 are values that satisfy the relationship of the first type Bessel function J0 (k0) = 0, where c is the speed of sound of the air passing through the blower chamber 131. Then, the relationship of 0.8 × (k0c) / (2π) ≦ af ≦ 1.2 × (k0c) / (2π) is satisfied.

  Furthermore, the radius a of the blower chamber 331 and the resonance frequency f of the diaphragm 141 satisfy the relationship of 0.8 × (k0c) / (2π) ≦ af ≦ 1.2 × (k0c) / (2π). In the present embodiment, the resonance frequency f is 21 kHz. The sound velocity c of air is 340 m / s. k0 is 2.40.

  Further, the pressure change distribution u (r) at each point in the blower chamber 131 is expressed by the equation u (r) = J0 (k0r / a), where r is the distance from the central axis C of the blower chamber 131. The The pressure change distribution u (r) at each point in the blower chamber 331 is also expressed by the equation u (r) = J0 (k0r / a).

  As shown in FIG. 18A, when the vibration plate 141 is bent to the piezoelectric element 47 side, the top plate portion 18 is bent to the opposite side to the piezoelectric element 47, and the volume of the blower chamber 131 is increased. Further, the top plate portion 318 is bent toward the piezoelectric element 47 side, and the volume of the blower chamber 331 is reduced.

  At this time, since the pressure in the central portion of the blower chamber 131 is reduced, the discharge valve 80 is closed. Further, since the pressure in the central portion of the blower chamber 331 increases, the valve 12 is closed. As a result, the air in the center of the blower chamber 331 is sucked into the blower chamber 131 through the opening 62.

  As shown in FIG. 18B, when the vibration plate 141 is bent toward the blower chamber 131, the top plate portion 18 is bent toward the piezoelectric element 47, and the volume of the blower chamber 131 is reduced. Furthermore, the top plate portion 318 is bent to the opposite side to the piezoelectric element 47, and the volume of the blower chamber 331 is increased.

  At this time, since the pressure in the central portion of the blower chamber 131 increases, the discharge valve 80 opens, and the air in the central portion of the blower chamber 131 is discharged to the outside of the housing 17 through the discharge hole 124. At this time, since the pressure in the central portion of the blower chamber 331 decreases, the valve 12 is opened. As a result, air outside the piezoelectric blower 300 is sucked into the blower chamber 331 through the suction hole 324.

  As described above, when the actuator 70 is driven, the piezoelectric blower 300 sucks the outside of the housing 317 through the suction hole 324 into the blower chamber 331 and causes the air in the blower chamber 131 to flow through the discharge hole 124. To the outside.

  In the piezoelectric blower 300, the top plate portions 18 and 318 vibrate with the vibration of the vibration plate 141, so that the vibration amplitude can be substantially increased. Thereby, the piezoelectric blower 300 of this embodiment can increase the suction pressure and the suction flow rate.

  Here, as shown in FIGS. 18A and 18B, the volume of the blower chamber 131 increases when the volume of the blower chamber 331 decreases, and the volume of the blower chamber 331 increases when the volume of the blower chamber 131 decreases. To do. That is, the volume of the blower chamber 131 and the volume of the blower chamber 331 change in opposite phases.

  Therefore, the air around the blower chamber 131 and the air around the blower chamber 331 move via the opening 62 when the actuator 70 is driven. Therefore, the pressure at the outer periphery of the blower chamber 131 and the pressure at the outer periphery of the blower chamber 331 cancel each other through the opening 62 when the actuator 70 is driven, and are always atmospheric pressure (node).

  When af = (k0c) / (2π), the vibration node F of the vibration plate 141 coincides with the pressure vibration node of the blower chamber 131 and the pressure vibration node of the blower chamber 331, and pressure resonance occurs. Arise. Further, even when the relationship of 0.8 × (k0c) / (2π) ≦ af ≦ 1.2 × (k0c) / (2π) is satisfied, the vibration node F of the vibration plate 141 causes the pressure vibration of the blower chamber 131. And the pressure vibration node of the blower chamber 331 substantially coincide with each other.

  The piezoelectric blower 300 is used for, for example, suctioning a highly viscous liquid such as a runny nose or sputum. In order to prevent the piezoelectric element from being damaged due to long-term driving, the vibration speed of the piezoelectric element needs to be 2 m / s or less. Since suction of a runny nose and sputum requires a pressure of 20 kPa or more, the piezoelectric blower 300 needs a pressure amplitude of 10 kPa / (m / s) or more. The pressure amplitude is maximum when af is 130 m / s. Even if it deviates ± 20% from there, the pressure amplitude is 10 kPa / (m / s) or more.

  Therefore, when the relationship of 0.8 × (k0c) / (2π) ≦ af ≦ 1.2 × (k0c) / (2π) is satisfied, the piezoelectric blower 300 is high from both the discharge hole 124 and the suction hole 324. A suction pressure and a high suction flow rate can be realized. The piezoelectric blower 300 can generate almost twice the suction pressure with one driver without increasing the power consumption.

  The fluid control device 311 includes the valve 12 described above. Therefore, similarly to the fluid control device 111, the fluid control device 311 can easily inspect the positional deviation between the top plate 21 and the bottom plate 23 with the movable plate 24 interposed therebetween.

<< Other Embodiments >>
In the above embodiment, air is used as the fluid, but the present invention is not limited to this. The fluid can also be applied to gases other than air.

  Moreover, in the said embodiment, although each board which comprises a valve | bulb and a piezoelectric blower is comprised from SUS, it is not restricted to this. For example, you may comprise from other materials, such as aluminum, titanium, magnesium, copper.

  In the above embodiment, the piezoelectric element is provided as the blower drive source, but the present invention is not limited to this. For example, it may be configured as a blower that performs a pumping operation by electromagnetic drive.

  Moreover, in the said embodiment, although the piezoelectric element is comprised from the lead zirconate titanate ceramics, it is not restricted to this. For example, it may be composed of a lead-free piezoelectric ceramic material such as potassium sodium niobate and alkali niobate ceramics.

  In the above embodiment, a unimorph type piezoelectric vibrator is used, but the present invention is not limited to this. A bimorph type piezoelectric vibrator in which the piezoelectric element 33 is attached to both surfaces of the vibrating body 36 may be used. Similarly, a bimorph type piezoelectric vibrator in which the piezoelectric element 47 is bonded to both surfaces of the vibrating body 136 may be used.

  In the embodiment, the disk-shaped piezoelectric elements 33 and 47 and the disk-shaped vibrating bodies 36 and 136 are used. However, the present invention is not limited to this. For example, these shapes may be rectangular or polygonal.

  Moreover, in the said embodiment, although k0 used the condition of 2.40, it does not restrict to this. K0 may be a value that satisfies the relationship of J0 (k0) = 0, such as 5.52, 8.65, 11.79, and 14.93.

  In the above-described embodiment, the vibration plate of the piezoelectric blower is flexibly vibrated at the frequency of the primary mode. However, the present invention is not limited to this. In implementation, the diaphragm may be bent and vibrated in an odd-order vibration mode that is a third-order mode or more that forms a plurality of vibration antinodes.

  Moreover, in the said embodiment, although the shape of the blower chambers 45, 131, 331 is a cylindrical shape, it is not restricted to this. In implementation, the shape of the blower chamber may be a regular prism shape. In this case, the shortest distance a from the central axis C of the blower chamber to the outer periphery F of the blower chamber is used instead of the radius a of the blower chamber.

  In the third embodiment, all the second vent holes 43 of the valve 12 are connected to the suction holes 324 of the piezoelectric blower 300, but the present invention is not limited to this. In implementation, all the second vent holes 43 of the valve 212 may be connected to the suction holes 324 of the piezoelectric blower 300.

  Finally, the above description of the embodiments should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above-described embodiments but by the claims. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

DESCRIPTION OF SYMBOLS 12 ... Valve | bulb 13 ... Piezoelectric blower 14 ... Control part 17 ... Housing 18 ... Top plate part 19 ... Side wall part 21 ... Top plate 22 ... Side wall plate 23 ... Bottom plate 24 ... Movable plate 25 ... Projection part 26 ... Notch part 31 ... Side wall Plate 32 ... Diaphragm 33 ... Piezoelectric element 34 ... Outer peripheral portion 35 ... Beam portion 36 ... Vibrating body 37 ... Actuator 40 ... Valve chamber 41 ... First vent hole 42 ... Third vent hole 43 ... Second vent hole 45 ... Blower chamber 46 ... suction hole 47 ... piezoelectric element 48 ... blower lower chamber 49 ... auxiliary hole 50 ... edge 54 ... vibration adjusting plate 55 ... blower upper chamber 62 ... opening 70 ... actuator 80 ... discharge valve 111 ... fluid control device 124 ... discharge Hole 131 ... Blower chamber 134 ... Outer peripheral part 135 ... Beam part 136 ... Vibrating body 141 ... Vibrating plate 141A ... First main surface 141B ... Second main surface 211 ... Fluid control device 212 ... Valve 223 ... Bottom plates 248X, 248Y ... Paper 249 Auxiliary hole 250 ... edge 300 ... piezoelectric blower 311 ... fluid control device 317 ... housing 318 ... top plate 319 ... side wall 324 ... suction hole 331 ... blower chamber 910 ... valve 914, 916 ... plate 917 ... flaps 918,920 ... Vent hole 928 ... Auxiliary hole

Claims (3)

An actuator having a diaphragm having a first main surface and a second main surface, a driving body that flexibly vibrates the diaphragm, and a first sandwiching the diaphragm from the thickness direction of the diaphragm together with the actuator. A blower having a housing constituting a blower chamber and a second blower chamber,
The diaphragm has a plurality of openings arranged in an annular shape,
The casing communicates the first blower chamber with the outside of the casing and has a discharge hole having a discharge valve for preventing fluid from flowing into the first blower chamber from the outside. The second blower chamber is connected to the casing. of not communicate with the outside have a, a suction hole having a suction valve to prevent outflow of fluid to the outside from the second blower chamber,
The diaphragm includes a vibrating body, an outer peripheral portion, and a beam portion that is disposed between the vibrating body and the outer peripheral portion and forms the plurality of openings together with the vibrating body and the outer peripheral portion.
Between the vibrating body and the outer peripheral portion is a space sandwiched between a side surface of the vibrating body and a side surface of the outer peripheral portion,
An inner space surrounded by the plurality of openings constitutes the first blower chamber,
Blower. The housing includes the discharge hole and the suction hole in a portion overlapping the driver when the first main surface of the diaphragm is viewed from the front.
The blower according to claim 1. The suction valve is closed when the discharge valve is closed, and the suction valve is opened when the discharge valve is opened;
The blower according to claim 1 or 2.

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