FLUID CONTROL APPARATUS

Description

CROSS REFERENCE TO RELATED APPLICATION

This is a continuation of International Application No. PCT/JP2023/042036 filed on Nov. 22, 2023 which claims priority from Japanese Patent Application No. 2023-043697 filed on Mar. 20, 2023. The contents of these applications are incorporated herein by reference in their entireties.

BACKGROUND OF THE DISCLOSURE

Field of the Disclosure

The present disclosure relates to a fluid control apparatus that includes a vibration body inside a housing and that controls a flow of fluid by vibration of the vibration body.

Description of the Related Art

International Publication No. 2022/070637 describes a fluid control apparatus. The fluid control apparatus described in International Publication No. 2022/070637 includes a pump including a vibration body and a housing containing the pump. The pump and a structure to support the pump define a first internal space and a second internal space in the housing.

The first internal space communicates with a space outside of the housing by a nozzle that functions as an intake hole. The second internal space communicates with a space outside of the housing by a nozzle that functions as an outlet hole.

The pump causes the vibration body with a piezoelectric device to vibrate to transfer fluid. When the pump is driven, fluid flows into the first internal space from the intake hole. The fluid flows to the second space through the pump and is discharged outside from the outlet hole.

BRIEF SUMMARY OF THE DISCLOSURE

In the fluid control apparatus using the vibration body as described in International Publication No. 2022/070637, the deformation of the piezoelectric device to vibrate the vibration body and the vibration of the vibration body generate heat, and the temperature of the vibration body increases. This increases the temperature of discharged fluid.

Therefore, a possible benefit of the present disclosure is to provide a fluid control apparatus having excellent heat dissipation properties.

A fluid control apparatus of the present disclosure includes a vibration unit, a housing, and a top-surface part. The vibration unit includes a piezoelectric material, a plate member on which the piezoelectric material is disposed, a frame plate surrounding a periphery of the plate member, and a coupling part coupling the plate member to the frame plate, the coupling part being configured to vibrate. The housing includes an annular side wall and a bottom wall. The top-surface part is coupled to the side wall of the housing and disposed apart from the bottom wall. The vibration unit is disposed in an internal space formed by being surrounded by the side wall, the bottom wall, and the top-surface part.

The top-surface part includes a main body including a principal surface opposed to the plate member, and a support body supporting the main body. The support body includes a wall protruding in a direction toward the bottom wall with respect to the principal surface to have a given height. The principal surface includes a portion exposed to the internal space.

In this configuration, part of a gas flow generated in response to vibration of the plate member of the vibration unit and to flow to an outlet port collides with the wall surface of the wall protruding from the principal surface of the main body of the top-surface part. Therefore, turbulence occurs at a vicinity of a portion of the internal space where the principal surface and the wall surface are coupled to one another. This turbulence causes a gas flow along the principal surface in a direction different from a direction toward the outlet port (for example, a direction opposite to the direction toward the outlet port). This gas flow causes heat contained in the gas flow to be propagated (diffused) over a large portion of the principal surface of the main body of the top-surface part. Thereby, the top-surface part has an improved heat dissipation effect.

According to the present disclosure, a fluid control apparatus having excellent heat dissipation properties is achievable.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a fluid control apparatus according to a first embodiment of the present disclosure.

FIGS. 2A and 2B are side sectional views of a configuration of the fluid control apparatus according to the first embodiment of the present disclosure.

FIG. 3 is an exploded perspective view of a top-surface part according to the first embodiment of the present disclosure.

FIG. 4 is a perspective view of a back-surface side of the top-surface part according to the first embodiment of the present disclosure.

FIG. 5 is an enlarged view of a side section schematically illustrating a state in which turbulence occurs and a heat dissipation principle.

FIG. 6 is a schematic side sectional view of a recess of a main body of the top-surface part according to the first embodiment of the present disclosure.

FIG. 7 is a perspective view of a back-surface side of a top-surface part according to a second embodiment.

FIG. 8 is a perspective view of a back-surface side of a top-surface part according to a third embodiment.

FIGS. 9A, 9B, and 9C are enlarged side sectional views of a stepped portion of a top-surface part in a fluid control apparatus according to a fourth embodiment.

FIGS. 10A, 10B, and 10C are enlarged side sectional views of a stepped portion of a top-surface part in a fluid control apparatus according to a fifth embodiment.

FIG. 11 is a side sectional view of a configuration of a fluid control apparatus including a protrusion part on a top-surface part.

DETAILED DESCRIPTION OF THE DISCLOSURE

First Embodiment

A fluid control apparatus according to a first embodiment of the present disclosure is described with reference to the drawings. FIG. 1 is an exploded perspective view of the fluid control apparatus according to the first embodiment of the present disclosure. FIGS. 2A and 2B are side sectional views of a configuration of the fluid control apparatus according to the first embodiment of the present disclosure. Note that FIGS. 2A and 2B do not illustrate a section strictly taken along a plane but illustrate a section that facilitates understanding of the configuration of the fluid control apparatus. Note that, in each of the drawings indicated in embodiments including this embodiment, the shapes of elements may be partly or entirely exaggerated to facilitate understanding of the configuration of the fluid control apparatus. Moreover, in the embodiments including this embodiment, one or some of reference characters in the drawings may be omitted to make the drawings easier to see.

As illustrated in FIG. 1, a fluid control apparatus 10 includes a vibration unit 20, a housing 30, and a top-surface part 40.

(Vibration Unit 20)

The vibration unit 20 includes a plate member 211, a frame plate 212, multiple coupling parts 213, multiple communication holes 214, a piezoelectric device 22, an electrode 23, and an insulation layer 24.

The plate member 211, the frame plate 212, and the multiple coupling parts 213 are formed integrally and are conductive bodies, such as metal plates. The plate member 211 is a flat plate having a circular shape in plan view (a shape seen in a thickness direction). The frame plate 212 is a flat plate and is disposed on an outer side of an outer edge of the plate member 211 to surround the plate member 211. The frame plate 212 includes an external coupling conductor 215 extending outward from an outer peripheral end.

Each of the multiple coupling parts 213 has a beam shape. The multiple coupling parts 213 are disposed between the plate member 211 and the frame plate 212. The multiple coupling parts 213 couple the outer edge of the plate member 211 to an inner edge of the frame plate 212. The multiple communication holes 214 are portions between the plate member 211 and the frame plate 212, where the multiple coupling parts 213 are not formed.

The piezoelectric device 22 includes a disk-shaped piezoelectric material and a drive electrode. The drive electrode is formed on each one of both principal surfaces of the piezoelectric material. The piezoelectric device 22 is disposed on a first principal surface of the plate member 211.

The electrode 23 is, for example, a metal plate and has the shape substantially the same as the shape of the frame plate 212. The electrode 23 includes an external coupling conductor 232 extending outward from an outer peripheral end, and a power supply conductor 233 extending inward from an inner peripheral end. The electrode 23 is disposed on the first principal surface side of the frame plate 212 while sandwiching the insulation layer 24 having substantially the same shape as the shape of the electrode 23 between the electrode 23 and the frame plate 212. The power supply conductor 233 is coupled to the piezoelectric device 22. More specifically, the power supply conductor 233 is coupled to the piezoelectric material through the drive electrode.

Note that the drive electrode of the piezoelectric device 22 with the configuration described above can be omitted. In this case, the piezoelectric device 22 may include only the piezoelectric material, and the plate member 211 made of a conductive material and the power supply conductor 233 serve as the drive electrode. That is, the power supply conductor 233 is directly coupled to the piezoelectric material.

(Housing 30)

The housing 30 includes a main member 31, a nozzle 321, and a nozzle 322. The main member 31, the nozzle 321, and the nozzle 322 are, for example, integrally molded by using an insulating resin material.

The main member 31 includes a bottom wall 311 and a side wall 312. The side wall 312 is provided upright in a direction orthogonal to a principal surface of the bottom wall 311. This shape causes the main member 31 to include a recess part 33 dented from a top-surface side.

The recess part 33 has a depth with three stages including a recess part 331, a recess part 332, and a recess part 333. The recess part 332 is deeper than the recess part 331, and the recess part 333 is deeper than the recess part 332. When the main member 31 is seen in plan view (when seen in the direction orthogonal to the bottom wall 311 (a Z-axis direction in FIG. 1)), the recess part 333 is disposed at a center. The recess part 332 is disposed along an outer periphery of the recess part 333. The recess part 331 is disposed along an outer periphery of the recess part 332.

The main member 31 includes a terminal placement part 35 protruding outward from the side wall 312. A front surface of the terminal placement part 35 includes a step and includes a first front surface 351 and a second front surface 352. The second front surface 352 is disposed lower than the first front surface 351. The side wall 312 of the main member 31 includes, at a portion where the terminal placement part 35 protrudes, a first opening 341 and a second opening 342. The first opening 341 and the second opening 342 have shapes penetrating the side wall 312.

The nozzle 321 and the nozzle 322 are attached to the side wall 312 of the main member 31. A through-hole 3210 of the nozzle 321 communicates with the recess part 333 of the main member 31.

A through-hole 3220 of the nozzle 322 communicates with the recess part 332 of the main member 31. At this time, a bottom surface of the recess part 331 includes, at a portion in a circumferential direction, a communication hole 339. The communication hole 339 has a hole shape dented and opened from the bottom surface of the recess part 331 and a side surface of the recess part 332. The through-hole 3220 and the recess part 332 communicate with one another through the communication hole 339.

(Top-Surface Part 40)

FIG. 3 is an exploded perspective view of the top-surface part according to the first embodiment of the present disclosure. FIG. 4 is a perspective view of a back-surface side of the top-surface part according to the first embodiment of the present disclosure.

The top-surface part 40 includes a support body 41 and a main body 42.

The support body 41 is made of, for example, an insulating resin. The support body 41 includes a flat plate 411 and a wall 413. The flat plate 411 has an equilateral octagonal annular shape including one principal surface 4111 and the other principal surface 4112 and includes a space 410. Note that the annular shape is not limited to the equilateral octagonal shape. The annular shape may be any polygonal shape, and may be a six or more-sided polygonal shape.

The wall 413 is disposed along an outer peripheral end of the flat plate 411 and is provided upright to have a given height from the one principal surface 4111 of the flat plate 411.

The main body 42 is, for example, a metal plate (plate-shaped metal) and includes a first principal surface 421, a second principal surface 422, and an outer side surface 429. The outer side surface 429 is substantially orthogonal to the first principal surface 421 and the second principal surface 422 and coupled to the first principal surface 421 and the second principal surface 422. The shape of the main body 42 in plan view is substantially the same as a shape indicated by an inner-side outline of the wall 413 of the support body 41. The first principal surface 421 corresponds to a “principal surface” of the present disclosure.

The main body 42 is disposed on the one principal surface 4111 of the support body 41. The first principal surface 421 of the main body 42 contacts the one principal surface 4111 of the flat plate 411 of the support body 41. Therefore, the support body 41 supports a peripheral portion of the main body 42. Here, the peripheral portion of the main body 42 is a portion in contact with or adjacent to the outer side surface 429, and is an annular portion with a given width when the main body 42 is seen in plan view (seen in a direction orthogonal to the first principal surface 421 or the second principal surface 422).

With this configuration, the flat plate 411 of the support body 41 has a shape protruding with respect to the first principal surface 421 of the main body 42. That is, the top-surface part 40 has a step formed by the first principal surface 421 of the main body 42 and an inner wall surface 4121 of the flat plate 411 of the support body 41.

The top-surface part 40 includes the space 410 surrounded by the inner wall surface 4121 of the flat plate 411 of the support body 41 and the first principal surface 421. The first principal surface 421 of the main body 42 is exposed to the space 410 side in a region on an inner side of the flat plate 411 when the top-surface part 40 is seen in plan view.

The outer side surface 429 of the main body 42 is opposed to an inner wall surface of the wall 413. The main body 42 and the support body 41 are, for example, adhered to one another by an adhesive 43 (see FIGS. 2A and 2B). Note that in each drawing (for example, in FIG. 2A, FIG. 2B, or FIG. 5), the adhesive 43 is disposed only between the outer side surface 429 of the main body 42 and the inner wall surface of the wall 413 of the support body 41. However, the adhesive 43 may be disposed also between the first principal surface 421 of the main body 42 and the one principal surface of the flat plate 411 of the support body 41.

(Arrangement of Vibration Unit 20 and Top-surface Part 40 in Housing 30)

The vibration unit 20 is fitted into the recess part 332. Therefore, the vibration unit 20 is disposed in the internal space 300 of the housing 30. At this time, the vibration unit 20 is disposed in the housing 30 in such a manner that the piezoelectric device 22 is positioned on the top-surface side (an opening side of the internal space 300 of the housing 30).

Note that the external coupling conductor 232 of the vibration unit 20 is disposed in such a manner as to protrude to the outside of the side wall 312 through the first opening 341 of the side wall 312, and is placed on the first front surface 351 of the terminal placement part 35. The external coupling conductor 215 of the vibration unit 20 is disposed in such a manner as to protrude to the outside of the side wall 312 through the second opening 342 of the side wall 312, and is placed on the second front surface 352 of the terminal placement part 35. Therefore, a driving signal can be supplied to the vibration unit 20 from the outside of the housing 30.

The top-surface part 40 is fitted into the recess part 331. Therefore, the top-surface part 40 covers the opening of the housing 30 on the top surface side. Accordingly, the internal space 300 surrounded by the housing 30 (the bottom wall 311 and the side wall 312) and the top-surface part 40 is formed.

More specifically, the top-surface part 40 is fitted into the recess part 331 in such a manner that the first principal surface 421 of the main body 42 faces the vibration unit 20. Here, a bottom surface (front surface) of the recess part 331 contacts the other principal surface 4112 (a surface opposite to the surface where the wall 413 is provided upright) of the flat plate 411 of the support body 41. The bottom surface (front surface) of the recess part 331 and the other principal surface 4112 of the flat plate 411 of the support body 41 are adhered to one another by an adhesive 50.

Therefore, the first principal surface 421 of the main body 42 of the top-surface part 40 is exposed to the internal space 300 (see FIGS. 2A and 2B) of the housing 30 communicating with the space 410 of the top-surface part 40. The support body 41 protrudes toward the bottom wall 311 of the housing 30, in other words, toward the internal space 300 with respect to the first principal surface 421 of the main body 42.

(Configuration and Operation of Fluid Control Apparatus 10)

With the configuration described above, the fluid control apparatus 10 includes the internal space 300 surrounded by the housing 30 and the top-surface part 40 (technically, also includes the space 410 of the top-surface part 40), and the vibration unit 20 is disposed in the internal space 300.

The internal space 300 is divided into a first space 301 and a second space 302 by the vibration unit 20. The first space 301 communicates with the through-hole 3210 of the nozzle 321. The second space 302 communicates with the space 410 of the top-surface part 40 and communicates with the through-hole 3220 of the nozzle 322. The first space 301 and the second space 302 communicate with one another through the multiple communication holes 214 of the vibration unit 20.

When a driving signal is applied to the piezoelectric device 22 of the vibration unit 20 from outside, the piezoelectric device 22 is deformed. Stress caused by the deformation of the piezoelectric device 22 is transmitted to the plate member 211, and the plate member 211 is subject to bending vibration.

The bending-vibration of the plate member 211 causes gas to flow in from the through-hole 3210 of the nozzle 321 and be transferred to the first space 301. In this manner, a portion where the through-hole 3210 of the nozzle 321 is exposed to the outside corresponds to an “inlet port” of the present disclosure. The gas transferred to the first space 301 is transferred to the second space 302 through the multiple communication holes 214. The gas transferred to the second space 302 flows out, through the communication hole 339 (through a space between a bottom wall of the communication hole 339 and the support body 41), to the outside from the through-hole 3220 of the nozzle 322. A portion where the through-hole 3220 of the nozzle 322 is exposed to the outside corresponds to an “outlet port” of the present disclosure.

In the configuration described above, the support body 41 of the top-surface part 40 protrudes toward the internal space 300 with respect to the first principal surface 421 of the main body 42. The top-surface part 40 includes the step formed by the first principal surface 421 of the main body 42 and the inner wall surface 4121 of the flat plate 411 of the support body 41.

FIG. 5 is an enlarged view of a side section schematically illustrating a state in which turbulence occurs and a heat dissipation principle. As illustrated in FIG. 5, in the second space 302, a gas flow flows toward the communication hole 339 as a downstream side (see a thick line in FIG. 5). The support body 41 protrudes from the first principal surface 421 of the main body 42 in such a manner as to have a given height, and part of the gas flow collides with the inner wall surface 4121 of the flat plate 411 of the support body 41. The inner wall surface 4121 is a surface facing the plate member 211 and the piezoelectric device 22 of the vibration unit 20 when the top-surface part 40 and the housing 30 are seen in plan view (seen in a direction parallel with the z-axis in the drawing).

Therefore, as illustrated in FIG. 5, besides a gas flow that flows from the second space 302 to the communication hole 339, turbulence including a gas flow that returns from the inner wall surface 4121 along the first principal surface 421 occurs.

Here, the piezoelectric device 22 generates heat in response to driving. Further, the heat is propagated to the plate member 211. The gas flow flowing into the second space 302 is heated and increased in temperature. Therefore, the temperature of the gas flow that has collided with the inner wall surface 4121 is high, and the temperature of the gas flow that returns (flows) along the first principal surface 421 by the turbulence is also high.

The gas flow caused by the turbulence flows along the first principal surface 421, and thus flows while contacting a large portion of the first principal surface 421. Therefore, heat of the gas flow is effectively propagated to the main body 42 and is dissipated to the outside of the fluid control apparatus 10 from the second principal surface 422 of the main body 42.

As a result, the temperature of the gas flow decreases. This decrease in the temperature of the gas flow and the turbulence also cause heat dissipation of the piezoelectric device 22 and the plate member 211. Accordingly, the fluid control apparatus 10 has excellent heat dissipation properties. Then, the excellent heat dissipation properties allow the fluid control apparatus 10 to suppress a decrease in gas transfer capacity and a decrease in reliability due to a temperature rise.

Note that, at this time, since the inner wall surface 4121 forms a polygonal shape, corners are present, and thus the turbulence is likely to occur more effectively. Particularly, since the inner wall surface 4121 forms a six or more-sided polygonal shape, the turbulence is likely to occur even more effectively. Therefore, the fluid control apparatus 10 has further improved heat dissipation properties.

(Recess of Main Body 42)

FIG. 6 is a schematic side sectional view of a recess of the main body of the top-surface part according to the first embodiment of the present disclosure.

In the fluid control apparatus 10, at the top-surface part 40, the support body 41 supports the outer side surface 429 and the peripheral portion of the main body 42, but does not support a center portion of the main body 42. The main body 42 has a thermal expansion coefficient higher than a thermal expansion coefficient of the support body 41.

In this case, heat of a gas flow flowing in the second space 302 causes the main body 42 to be curved and dented toward the second space 302 as illustrated in FIG. 6. This reduces the height of the second space 302, that is, the distance between the main body 42 of the top-surface part 40, and the piezoelectric device 22 and the plate member 211 of the vibration unit 20. Therefore, the flow speed of the gas flow flowing in the second space 302 increases, and heat dissipation properties further improve.

Particularly, since the support body 41 supports the outer side surface 429 of the main body 42, the main body 42 is curved more easily than in a case in which a portion of the main body 42 closer to the center is supported. Therefore, the fluid control apparatus 10 can further increase the flow speed of the gas flow flowing in the second space 302 and further improve heat dissipation properties.

Note that the support body 41 may protrude in any shape from the main body 42 as long as the protruding shape is present at least at a portion of the second space 302 communicating with the communication hole 339. For example, the protruding shape is not necessarily present at a portion of the second space 302 opposite to the portion communicating with the communication hole 339 with respect to the position of the plate member 211 and the piezoelectric device 22 of the vibration unit 20 (a portion on a side connected to the through-hole 3210 of the nozzle 321).

Moreover, in the configuration described above, the piezoelectric device 22 is disposed on the surface of the plate member 211 of the vibration unit 20 closer to the top-surface part 40 (a first arrangement of the piezoelectric device 22). However, the piezoelectric device 22 may be disposed on the surface of the plate member 211 on the opposite side from the top-surface part 40 (a second arrangement of the piezoelectric device 22).

In the first arrangement of the piezoelectric device 22, the piezoelectric device 22 is adjacent to and opposed to the main body 42 of the top-surface part 40. Therefore, heat of the piezoelectric device 22 is easily conducted to the main body 42, and the piezoelectric device 22 can have an improved heat dissipation effect.

In the second arrangement of the piezoelectric device 22, the height of the second space 302 (the distance between the plate member 211 of the vibration unit 20 and the main body 42 of the top-surface part 40) can be reduced while heat dissipation is performed through the plate member 211 of the vibration unit 20. Therefore, heat of the plate member 211 is easily conducted to the main body 42. Further, the flow speed of a gas flow in the second space 302 can be increased.

Second Embodiment

A fluid control apparatus according to a second embodiment of the present disclosure is described with reference to the drawing. FIG. 7 is a perspective view of a back-surface side of a top-surface part according to the second embodiment. The fluid control apparatus according to the second embodiment is different from the fluid control apparatus 10 according to the first embodiment in that the fluid control apparatus according to the second embodiment includes a top-surface part 40A. Other configurations of the fluid control apparatus according to the second embodiment are similar to those of the fluid control apparatus 10 according to the first embodiment, and description of similar parts is omitted.

As illustrated in FIG. 7, the shape of an inner wall surface 4121A of the support body 41 is a circular shape when the top-surface part 40A is seen in plan view. In this manner, the shape of the inner wall surface 4121A of the support body 41 is not limited to a polygonal shape, but may be a circular shape. Further, the shape of the inner wall surface 4121A of the support body 41 may be a shape other than a precise circle, such as an oval shape.

Third Embodiment

A fluid control apparatus according to a third embodiment of the present disclosure is described with reference to the drawing. FIG. 8 is a perspective view of a back-surface side of a top-surface part according to the third embodiment. The fluid control apparatus according to the third embodiment is different from the fluid control apparatus 10 according to the first embodiment in that the fluid control apparatus according to the third embodiment includes a top-surface part 40B. Other configurations of the fluid control apparatus according to the third embodiment are similar to those of the fluid control apparatus 10 according to the first embodiment, and description of similar parts is omitted.

The top-surface part 40B is different from the top-surface part 40 of the first embodiment in that the top-surface part 40B includes multiple braces 44. The multiple braces 44 are disposed in the space 410 surrounded by the flat plate 411 and are coupled to the flat plate 411.

In this manner, the top-surface part 40B may have a shape with the first principal surface 421 of the main body 42 partially exposed. The shape and arrangement of the braces 44 can appropriately be set. At this time, the exposed area of the first principal surface 421 may be larger than the area in contact with the braces 44.

Fourth Embodiment

A fluid control apparatus according to a fourth embodiment of the present disclosure is described with reference to the drawings. FIGS. 9A, 9B, and 9C are enlarged side sectional views of a stepped portion of a top-surface part in the fluid control apparatus according to the fourth embodiment. In each of FIGS. 9A, 9B, and 9C, the shape of an inner wall surface of a support body is different.

In fluid control apparatuses 10C1, 10C2, and 10C3 according to the fourth embodiment, the shape of the inner wall surface of the support body is different from that of the fluid control apparatus 10 according to the first embodiment. Other configurations of the fluid control apparatuses 10C1, 10C2, and 10C3 are similar to those of the fluid control apparatus 10 according to the first embodiment, and description of similar parts is omitted.

As illustrated in FIG. 9A, an inner wall surface 4121C1 of a support body 41C1 of the fluid control apparatus 10C1 includes continuous unevenness.

As illustrated in FIG. 9B, an inner wall surface 4121C2 of a support body 41C2 of the fluid control apparatus 10C2 includes multiple protrusion parts each independently protruding from a flat surface.

As illustrated in FIG. 9C, an inner wall surface 4121C3 of a support body 41C3 of the fluid control apparatus 10C3 includes multiple protrusion parts and recess parts each independently protruding or dented from a flat surface.

In this manner, since the unevenness, the protrusion parts, and the recess parts are included, a turbulence occurrence effect improves. Therefore, the fluid control apparatuses 10C1, 10C2, and 10C3 have an excellent heat dissipation effect.

Fifth Embodiment

A fluid control apparatus according to a fifth embodiment of the present disclosure is described with reference to the drawings. FIGS. 10A, 10B, and 10C are enlarged side sectional views of a stepped portion of a top-surface part in the fluid control apparatus according to the fifth embodiment. In each of FIGS. 10A, 10B, and 10C, the shape of an inner wall surface of a support body is different.

In fluid control apparatuses 1001, 10D2, and 10D3 according to the fifth embodiment, the shape of the inner wall surface of the support body is different from that of the fluid control apparatus 10 according to the first embodiment. Other configurations of the fluid control apparatuses 10D1, 10D2, and 10D3 are similar to those of the fluid control apparatus 10 according to the first embodiment, and description of similar parts is omitted.

As illustrated in FIG. 10A, an inner wall surface 4121D1 of a support body 41D1 of the fluid control apparatus 10D1 has a shape in which an end portion closer to the vibration unit 20 is positioned closer to the center of the vibration unit 20 with respect to an end portion that contacts the main body 42. That is, the inner wall surface 4121D1 of the support body 41D1 is not orthogonal to the first principal surface 421 of the main body 42. An angle between the first principal surface 421 and the inner wall surface 4121D1 of the support body 41D1 (an angle on the second space 302 side) in side view is an acute angle.

As illustrated in FIG. 10B, an inner wall surface 4121D2 of a support body 41D2 of the fluid control apparatus 10D2 has a shape in which a center portion is dented with respect to both ends in side view.

As illustrated in FIG. 10C, an inner wall surface 4121D3 of a support body 41D3 of the fluid control apparatus 10D3 has a shape in which a center portion is bulged with respect to both ends in side view.

The inner wall surfaces of the support bodies having such shapes improve a turbulence occurrence effect. Therefore, the fluid control apparatuses 1001, 10D2, and 10D3 have an excellent heat dissipation effect.

Note that in the embodiments described above the first principal surface 421 of the main body 42 of the top-surface part is a flat surface. However, the first principal surface 421 of the top-surface part may include a protrusion part.

FIG. 11 is a side sectional view of a configuration of a fluid control apparatus including a protrusion part on a top-surface part. A fluid control apparatus 10E illustrated in FIG. 11 is different from the fluid control apparatus 10 according to the first embodiment in that the fluid control apparatus 10E includes multiple protrusion parts 49 on the main body 42 of a top-surface part 40E. Other configurations of the fluid control apparatus 10E are similar to those of the fluid control apparatus 10 according to the first embodiment, and description of similar parts is omitted.

The fluid control apparatus 10E includes the top-surface part 40E. The top-surface part 40E includes the multiple protrusion parts 49. The multiple protrusion parts 49 protrude from the first principal surface 421 of the top-surface part to the second space 302. Note that although the number of the protrusion parts 49 may be one, the number of the protrusion parts 49 may be two or more as illustrated in FIG. 11. When the protrusion parts 49 are included, heat exchange with a gas flow in the second space 302 can be facilitated. That is, heat of the gas flow in the second space 302 can effectively be dissipated to the main body 42.

The protrusion part 49 may have a rectangular parallelepiped shape including a surface in a direction of a gas flow. This improves a heat exchange effect by the protrusion part 49. Note that the protrusion part 49 may have a shape to appropriately control a gas flow.

The protrusion part 49 may overlap the multiple communication holes 214 of the vibration unit 20 when the fluid control apparatus 10E is seen in plan view. This allows the multiple communication holes 214 to easily contact the protrusion part 49 and improves a heat exchange effect by the protrusion part 49.

The protrusion part 49 may or may not overlap the piezoelectric device 22 when the fluid control apparatus 10E is seen in plan view. In the case in which the protrusion part 49 overlaps the piezoelectric device 22, the fluid control apparatus 10E can effectively dissipate heat of the piezoelectric device 22 to the main body 42 through the protrusion part 49. In the case in which the protrusion part 49 does not overlap the piezoelectric device 22, contact of the piezoelectric device 22 with the protrusion part 49 due to vibration of the vibration unit 20 can be suppressed.

Moreover, the configurations of the respective embodiments describe above can be combined as appropriate, and can achieve operation and effects in accordance with each combination.

• • <1> A fluid control apparatus including: a vibration unit including: a piezoelectric material; a plate member on which the piezoelectric material is disposed; a frame plate surrounding a periphery of the plate member; and a coupling part coupling the plate member to the frame plate, the coupling part being configured to vibrate; a housing including an annular side wall and a bottom wall; and a top-surface part coupled to the side wall of the housing and disposed apart from the bottom wall, wherein the vibration unit is disposed in an internal space formed by being surrounded by the side wall, the bottom wall, and the top-surface part, the top-surface part includes: a plate-shaped main body including a principal surface opposed to the plate member; and a support body supporting the main body, the support body includes a wall protruding in a direction toward the bottom wall with respect to the principal surface to have a given height, and the principal surface includes a portion exposed to the internal space.
  • <2> The fluid control apparatus of <1>, wherein the main body is a metal plate.
  • <3> The fluid control apparatus of <1> or <2>, wherein the main body has a thermal expansion coefficient higher than a thermal expansion coefficient of the support body.
  • <4> The fluid control apparatus of <3>, wherein the support body supports an outer side surface of the main body.
  • <5> The fluid control apparatus of any one of <1> to
  • <4>, wherein an exposed surface of the principal surface to the internal space has a six or more-sided polygonal shape.
  • <6> The fluid control apparatus of any one of <1> to <5>, wherein a side wall surface of the wall protruding from the principal surface includes unevenness.
  • <7> The fluid control apparatus of any one of <1> to <6>, wherein the plate member includes a surface closer to the top-surface part and a surface on an opposite side from the top-surface part, and the piezoelectric material is disposed on the surface closer to the top-surface part.
  • <8> The fluid control apparatus of any one of <1> to <7>, wherein the plate member includes a surface closer to the top-surface part and a surface on an opposite side from the top-surface part, and the piezoelectric material is disposed on the surface on the opposite side from the top-surface part.
  • 10, 10C1, 10C2, 10C3, 10D1, 10D2, 10D3, 10E fluid control apparatus
  • 20 vibration unit
  • 22 piezoelectric device
  • 23 electrode
  • 24 insulation layer
  • 30 housing
  • 31 main member
  • 33 recess part
  • 35 terminal placement part
  • 40, 40A, 40B top-surface part
  • 41, 41C1, 41C2, 41C3, 41D1, 41D2, 41D3 support body
  • 42 main body
  • 43, 50 adhesive
  • 44 brace
  • 49 protrusion part
  • 211 plate member
  • 212 frame plate
  • 213 coupling part
  • 214 communication hole
  • 215, 232 external coupling conductor
  • 233 power supply conductor
  • 300 internal space
  • 301 first space
  • 302 second space
  • 311 bottom wall
  • 312 side wall
  • 321, 322 nozzle
  • 331, 332, 333 recess part
  • 339 communication hole
  • 341 first opening
  • 342 second opening
  • 351 first front surface
  • 352 second front surface
  • 410 space
  • 411 flat plate
  • 413 wall
  • 421 first principal surface
  • 422 second principal surface
  • 429 outer side surface
  • 3210, 3220 through-hole
  • 4111 one principal surface
  • 4112 other principal surface
  • 4121, 4121A, 4121C1, 4121C2, 4121C3, 4121D1, 4121D2, 4121D3 inner wall surface