JP2013151908A - Fluid control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid control device which is small in size and short in height, and can further increase a discharge flow rate of the fluid control device in its unloaded condition independently of a capacity of a pump.SOLUTION: A fluid control device 100 is equipped with a piezoelectric pump 15 and a cover case 101. The cover case 101 is attached to an upper surface 14 of an outer case 17 of the piezoelectric pump 15. By this, a ventilation passage 105 for introducing air from an outside of the fluid control device 100 is formed between the cover case 101 and the outer case 17 of the piezoelectric pump 15. The ventilation passage 105 includes a ventilation passage 105A formed between the cover case 101 and an upper surface 14 of the outer case 17 which is parallel to a vibration plate 39 and is on the opposite side to the vibration plate 39. In the cover case 101, an outlet 102 is formed in a position opposite to an exhaust port 24 of the piezoelectric pump 15 via the ventilation passage 105A. The ventilation passage 105A is perpendicular to the central axis passing through the center of the exhaust port 24 and the center of the outlet 102.

Description

  The present invention relates to a fluid control device used for fluid transportation.

  Conventionally, various fluid control devices for fluid transportation have been devised for cooling the heat generated inside a portable electronic device or for supplying oxygen necessary for power generation by a fuel cell. Patent Document 1 discloses a fluid control device that supplies oxygen to a cathode chamber of a fuel cell.

  FIG. 14 is a cross-sectional view around the air supply hole 952 and the air intake hole 953 through which the air discharged from the pump flows out in the fluid control device of Patent Document 1.

  In the fluid control device of Patent Document 1, air 901 discharged from the air supply hole 952 by the air supply pump AP through the air supply path AL1 is supplied to the cathode chamber 915. When the air 901 exits from the air supply hole 952, the air 901 entrains and moves the surrounding air, so that the pressure around the flow of the air 901 decreases. As a result, the pressure around the outlet 953b of the air inlet hole 953 provided around the air supply hole 952 decreases.

  Therefore, since the inlet 953a of the air inlet hole 953 communicates with the outside of the cathode chamber 915, the air 902 is drawn from the outside of the cathode chamber 915 into the cathode chamber 915 through the air inlet hole 953.

  Therefore, the amount of air 903 supplied to the cathode chamber 915 is the amount of air supplied by the air supply pump AP through the air supply path AL1 and the air supply hole 952, and the air drawn into the cathode chamber 915 through the air intake hole 953. Total with the amount.

JP 2007-53045 A

  However, in the above-described fluid control device of Patent Document 1, the air supply hole 952 and the air intake hole 953 positioned around the air supply hole 952 extend from the air supply pump AP side in substantially the same direction and merge. .

  Therefore, the flow of air 901 discharged from the air supply hole 952 through the air supply path AL1 by the air supply pump AP and the flow of air 902 drawn from the outside of the cathode chamber 915 through the air intake hole 953 are almost the same. In the same direction. And since the flow of the air 902 is made by the air inlet hole 953, the length L1 of the air inlet hole 953 needs to be a predetermined length.

  For this reason, in the fluid control device of Patent Document 1, the dimensions of the fluid control device in the direction in which the air 901 and 902 flow are lengthened, and the reduction in size and height of the fluid control device is hindered.

  Therefore, an object of the present invention is to provide a fluid control device that is small and low in profile and can further increase the discharge flow rate of the fluid control device when there is no load regardless of the capacity of the pump.

  The fluid control device of the present invention has the following configuration in order to solve the above problems.

(1) A diaphragm that vibrates flexibly, and an outer peripheral portion of the diaphragm is fixed to form a pump chamber together with the diaphragm, and the inside and outside of the pump chamber are formed on a wall surface of the pump chamber facing the diaphragm. A first air passage is formed between the first housing part formed with an opening that communicates with the first housing part and the first housing part, and the first air passage is formed between the first housing part and the first housing part. A second casing part having discharge holes formed at opposing positions, and a pump for discharging gas from the discharge holes by vibration of the diaphragm;
A cover housing that is attached to the second housing portion of the pump and forms a second air passage between the main surface of the second housing portion that is parallel to the diaphragm and opposite to the diaphragm. A fluid control device comprising:
The first air passage and the second air passage communicate with the outside of the fluid control device body,
The cover housing has a discharge hole formed at a position facing the discharge hole via the second air passage,
The second air passage is orthogonal to a central axis connecting the center of the discharge hole and the center of the discharge hole.

  In this configuration, since the air flow discharged from the discharge hole of the pump is discharged from the discharge hole while drawing the gas existing outside the fluid control apparatus through the second air passage, the discharge flow rate of the fluid control apparatus at no load is Increased by the amount of gas drawn.

  In this configuration, the second air passage is orthogonal to the central axis connecting the center of the discharge hole and the center of the discharge hole. Here, orthogonal includes an angle of approximately 90 °. Therefore, the flow of the first air discharged from the discharge hole by the pump is orthogonal to the flow of the second air drawn from the outside of the cover housing through the second air passage. For this reason, even if the length of the second air passage is formed long, the height of the fluid control device does not increase, so that a low profile can be realized.

  Therefore, according to this configuration, the discharge flow rate of the fluid control device at the time of no load can be further increased regardless of the capacity (discharge flow rate and discharge pressure) of the pump with a small size and a low profile.

(2) It is preferable that the cover housing is detachably attached to the second housing portion of the pump.

  In this configuration, the flow rate of discharge from the discharge hole can be adjusted without changing the pump by adjusting the shape of the cover housing attached to the second housing portion. Therefore, according to this configuration, the versatility of the pump is enhanced.

  According to the present invention, the discharge flow rate of the fluid control device at no load can be further increased regardless of the capacity of the pump with a small size and a low profile.

1 is an external perspective view of a casing 10 of an electronic device 1 to which a fluid control device 100 according to an embodiment of the present invention is attached. It is an external appearance perspective view of the fluid control apparatus 100 shown in FIG. It is the external appearance perspective view of the fluid control apparatus 100 which looked at the fluid control apparatus 100 shown in FIG. 2 from the bottom face side. FIG. 4 is an external perspective view of a cover housing 101 with a piezoelectric pump 15 removed from the fluid control device 100 shown in FIG. 3. FIG. 4 is an exploded perspective view of the piezoelectric pump 15 shown in FIG. 3. 6A is a cross-sectional view of the fluid control device 100 shown in FIG. FIG. 6B is a cross-sectional view taken along the line TT. It is sectional drawing of the SS line | wire of the fluid control apparatus 100 at the time of operation | movement of the fluid control apparatus 100 shown in FIG. It is explanatory drawing which shows the measuring method of the discharge flow volume of the fluid control apparatus 100 at the time of no load. FIG. 5 is a diagram comparing the discharge flow rate when the piezoelectric pump 15 alone is not loaded and the discharge flow rate when the fluid control device 100 is unloaded. It is a figure which shows the relationship between the distance between the discharge hole 24 and the discharge hole 102, and the discharge flow volume of the fluid control apparatus 100 at the time of no load. It is a figure which shows the relationship between the diameter of the discharge hole 102, and the discharge flow volume of the fluid control apparatus 100 at the time of no load. It is the external appearance perspective view of the fluid control apparatus 200 which looked at the fluid control apparatus 200 which concerns on the modification of embodiment of this invention from the bottom face side. FIG. 13 is an external perspective view of a cover housing 201 with the piezoelectric pump 15 removed from the fluid control device 200 shown in FIG. 12. FIG. 10 is a cross-sectional view around the air supply hole 952 and the air intake hole 953 through which air discharged from a pump flows out in the fluid control device of Patent Document 1.

<< Embodiment of the Present Invention >>
Hereinafter, a fluid control apparatus 100 according to an embodiment of the present invention will be described.
FIG. 1 is an external perspective view of a casing 10 of an electronic device 1 to which a fluid control device 100 according to an embodiment of the present invention is attached. FIG. 2 is an external perspective view of the fluid control apparatus 100 according to the embodiment of the present invention. FIG. 3 is an external perspective view of the fluid control apparatus 100 as viewed from the bottom side of the fluid control apparatus 100 shown in FIG. 4 is an external perspective view of the cover housing 101 with the piezoelectric pump 15 removed from the fluid control device 100 shown in FIG.

  The electronic device 1 is a portable video camera with a built-in hard disk drive, for example, and has a casing 10 in which a vent hole 11 is formed. As shown in FIGS. 3 to 4, the fluid control device 100 includes a piezoelectric pump 15 and a cover housing 101, and is attached to the inner surface of the casing 10 of the electronic device 1. Here, the diameter of the vent hole 11 is 1.5 mm.

  For example, the fluid control device 100 blows air from the inside of the casing 10 to the outside of the casing 10. That is, the fluid control apparatus 100 discharges warm air generated in the casing 10 of the electronic device 1 to the outside of the casing 10 through the vent hole 11 and cools the inside of the casing 10.

First, the structure of the piezoelectric pump 15 will be described in detail.
FIG. 5 is an exploded perspective view of the piezoelectric pump 15 shown in FIG. 6A is a cross-sectional view taken along line SS of the fluid control device 100 shown in FIG. 2, and FIG. 6B is a cross-sectional view taken along line TT.

  5 and 6A and 6B, the piezoelectric pump 15 includes, in order from the top, the outer casing 17, the top plate 37 of the pump chamber 36, the side plate 38 of the pump chamber 36, the vibration plate 39, and the piezoelectric element. 40, a spacer 41, and a cap 42, and has a structure in which these are laminated in order. The piezoelectric pump 15 has a size of width 20 mm × length 20 mm × height of the region other than the nozzle 18 1.85 mm.

  The joined body of the top plate 37, the side plate 38, and the spacer 41 corresponds to the “first casing” of the present invention, and the outer casing 17 corresponds to the “second casing” of the present invention.

  The outer casing 17 has a nozzle 18 having a discharge hole 24 through which air is discharged. The nozzle 18 has a size of an outer diameter of 2.0 mm × an inner shape (that is, a discharge hole 24) of 0.8 mm in diameter × 1.6 mm in height. Screw holes 56 </ b> A to 56 </ b> D are formed in the square of the outer casing 17. The outer casing 17 is formed in a U-shaped cross section with an opening at the bottom. The outer casing 17 includes a top plate 37 of the pump chamber 36, a side plate 38 of the pump chamber 36, a vibration plate 39, a piezoelectric element 40, and a spacer. 41 is stored from below.

  The top plate 37 of the pump chamber 36 has a disc shape and is made of, for example, metal. The top plate 37 is formed with a central portion 61, a key-like protruding portion 62 that protrudes horizontally from the central portion 61 and contacts the inner wall of the outer casing 17, and an external terminal 63 for connecting to an external circuit. Has been. In addition, the central portion 61 of the top plate 37 is provided with an opening 45 that allows the inside and the outside of the pump chamber 36 to communicate with each other. The opening 45 is formed at a position facing the discharge hole 24 of the outer casing 17. The central portion 61 of the top plate 37 is joined to the upper surface of the side plate 38. The top plate 37 forms the air passage 31 between the outer periphery of the central portion 61 and the inner wall of the outer casing 17.

  The side plate 38 of the pump chamber 36 has an annular shape, and is made of, for example, metal. The side plate 38 is joined to the upper surface of the diaphragm 39. Therefore, the thickness of the side plate 38 constitutes the height of the pump chamber 36. Further, the outer periphery of the side plate 38 forms an air passage 31 with the inner wall of the outer casing 17.

  The diaphragm 39 has a disk shape similar to the top plate 37, and is made of, for example, metal. The diaphragm 39 constitutes the bottom surface of the pump chamber 36. A ventilation path 31 is formed between the outer periphery of the diaphragm 39 and the inner wall of the outer casing 17.

  The piezoelectric element 40 has a disk shape, and is made of, for example, lead zirconate titanate ceramic. The piezoelectric element 40 is bonded to the main surface of the diaphragm 39 opposite to the pump chamber 36 and bends according to the applied AC voltage.

  The spacer 41 has an annular shape similar to that of the side plate 38, and is made of, for example, resin. The spacer 41 is formed to have substantially the same thickness as the piezoelectric element 40, and the inner peripheral edge of the spacer 41 is larger in diameter than the piezoelectric element 40. An opening region 51 surrounded by the inner periphery of the spacer 41 is a region where the diaphragm 39 can be bent and deformed. The spacer 41 electrically insulates the electrode conduction plate 70 from the diaphragm 39.

  A cap 42 is joined to the lower surface of the spacer 41 with a metal electrode conduction plate 70 interposed therebetween. The electrode conduction plate 70 includes an internal terminal 73 protruding toward the opening region 51 and an external terminal 72 for connecting to an external circuit.

  The tip of the internal terminal 73 is soldered to the surface of the piezoelectric element 40. By setting the soldering position to a position corresponding to the bending vibration node of the piezoelectric element 40, the vibration of the internal terminal 73 can be suppressed.

  An opening region 53 that communicates with the opening region 51 is formed in the cap 42. The cap 42 has notches 55 </ b> A to 55 </ b> D formed at positions corresponding to the screw holes 56 </ b> A to 56 </ b> D of the outer casing 17.

  Moreover, the cap 42 has the protrusion part 52 which protrudes in the outer periphery at the top plate 37 side. The cap 42 holds the outer casing 17 with the protruding portion 52, and houses the top plate 37 of the pump chamber 36, the side plate 38 of the pump chamber 36, the vibration plate 39, the piezoelectric element 40, and the spacer 41 together with the outer casing 17. .

  Next, as shown in FIG. 4, screw holes 116 </ b> A to 116 </ b> D are formed in the cover housing 101. The cover housing 101 is made of resin and has dimensions of 25 mm width × 25 mm length × 10 mm height.

  Here, as shown in FIGS. 3 to 5, screws (not shown) are attached to the cover housing in a state where the upper surface 14 of the outer housing 17 of the piezoelectric pump 15 is in contact with the mounting surfaces 114 </ b> A to 114 </ b> D of the cover housing 101. The screw holes 116A to 116D of the body 101 and the screw holes 56A to 56D of the outer casing 17 are fitted. Thereby, the cover casing 101 is attached to the upper surface 14 of the outer casing 17 of the piezoelectric pump 15. Therefore, the cover housing 101 is detachably attached to the outer housing 17 of the piezoelectric pump 15.

  Further, as shown in FIGS. 3, 6 </ b> A and 6 </ b> B, the cover housing 101 is for introducing air from the outside of the fluid control device 100 to the outer housing 17 of the piezoelectric pump 15. A ventilation path 105 is formed. The air passage 105 is formed through an air passage 105 </ b> A that is a space between the upper surface 14 of the outer housing 17 formed in parallel with the diaphragm 39 and the top plate 104 of the cover housing 101 formed in the same manner. Including.

Further, a discharge hole 102 is formed in the cover housing 101 at a position facing the discharge hole 24 of the piezoelectric pump 15 via the air passage 105A. The air passage 105 </ b> A is orthogonal to the central axis connecting the center of the discharge hole 24 and the center of the discharge hole 102. And the cover housing | casing 101 is attached to the inner surface of the casing 10 in the state which match | combined the discharge hole 102 and the ventilation hole 11 of the casing 10. FIG. Here, the diameter of the discharge hole 102 is the same as the diameter of the vent hole 11 and is 1.5 mm.
The air passage 105A corresponds to the “second air passage” of the present invention.

  Hereinafter, the air flow during the operation of the fluid control apparatus 100 will be described.

  7A and 7B are cross-sectional views of the fluid control device 100 taken along the line S-S during operation of the fluid control device 100 shown in FIG. Here, the arrows in the figure indicate the flow of air.

  In the state shown in FIG. 6, when an AC voltage is applied to the piezoelectric element 40 from the external terminals 63 and 72 to bend the diaphragm 39, as shown in FIGS. 7A and 7B, the diaphragm 39 is The volume of the pump chamber 36 changes periodically due to bending deformation.

  As shown in FIG. 7A, when an alternating voltage is applied to the piezoelectric element 40 and the diaphragm 39 is bent toward the piezoelectric element 40, the volume of the pump chamber 36 increases. Accordingly, the air inside the casing 10 of the electronic device 1 existing outside the fluid control device 100 is sucked into the pump chamber 36 through the ventilation path 31 and the opening 45. Although there is no outflow of air from the pump chamber 36, the inertial force of the air flow from the discharge hole 24 to the discharge hole 102 works.

  Therefore, the airflow discharged from the discharge hole 24 draws air inside the casing 10 of the electronic device 1 existing outside the fluid control device 100 through the air passage 105 and from the discharge hole 102 and the air hole 11 to the cover housing. It is discharged outside the body 101.

  As shown in FIG. 7B, when an alternating voltage is applied to the piezoelectric element 40 and the diaphragm 39 is bent toward the pump chamber 36, the volume of the pump chamber 36 decreases. Along with this, the air in the pump chamber 36 is discharged from the discharge hole 24 through the opening 45 and the air passage 31. At this time, the air flow discharged from the pump chamber 36 is discharged from the discharge hole 24 while drawing the air inside the casing 10 of the electronic device 1 existing outside the fluid control device 100 through the air passage 31.

  Further, the air discharged from the discharge hole 24 is discharged to the outside of the cover housing 101 through the discharge hole 102 and the vent hole 11 via the vent path 105. At this time, the air flow discharged from the discharge hole 24 draws air inside the casing 10 of the electronic device 1 existing outside the fluid control device 100 through the air passage 105, and from the discharge hole 102 and the air hole 11 to the cover housing. It is discharged outside the body 101.

In the above configuration, the airflow discharged from the piezoelectric pump 15 through the discharge hole 24 is discharged from the discharge hole 102 and the vent hole 11 while drawing air existing outside the fluid control device 100 through the vent path 105. Therefore, the flow rate of the air discharged from the discharge hole 102 and the vent hole 11 at the time of no load increases by the amount of the drawn air.
Here, as described above, the air passage 105 </ b> A is an air passage formed between the upper surface 14 of the outer housing 17 parallel to the diaphragm 39 and opposite to the diaphragm 39 and the cover housing 101.

  In the above configuration, the air passage 105 </ b> A is orthogonal to the central axis connecting the center of the discharge hole 24 and the center of the discharge hole 102. Therefore, the flow of the first air discharged from the discharge hole 24 by the piezoelectric pump 15 and the flow of the second air drawn from the outside of the cover housing 101 via the air passage 105A are orthogonal to each other.

  Here, in order to create the second air flow with the air passage 105A, a length L2 of the air passage 105A (see FIG. 6A) is required to be a predetermined length, but the air passage 105A has the central axis. Since they are orthogonal to each other, the height of the fluid control device 100 does not increase even if the length L2 of the air passage 105A is long.

  Therefore, according to the fluid control device 100 of this embodiment, the discharge flow rate of the fluid control device 100 at the time of no load is further increased regardless of the capacity (discharge flow rate and discharge pressure) of the piezoelectric pump 15 while being small and low-profile. Can be increased.

  Further, as described above, the cover casing 101 is detachably attached to the outer casing 17 of the piezoelectric pump 15. Therefore, by adjusting the shape of the cover casing 101 attached to the outer casing 17, the discharge flow rate from the discharge hole 102 can be adjusted without changing the piezoelectric pump 15. Therefore, according to the fluid control apparatus 100 of this embodiment, the versatility of the piezoelectric pump 15 is enhanced.

  Hereinafter, as an example, the result of quantitative measurement is shown.

  First, the flow rate of air discharged from the fluid control apparatus 100 is compared with the flow rate of air discharged from the piezoelectric pump 15 alone with the cover housing 101 removed. First, a method for measuring the flow rate at no load that represents the maximum discharge flow rate of the air will be described.

  FIG. 8 is an explanatory diagram showing a method for measuring the discharge flow rate of the fluid control device 100 when there is no load. This figure shows an example of the fluid control device 100 in which an attachment 504 in which a hole is formed at a position corresponding to the discharge hole 24 of the piezoelectric pump 15 is attached to the piezoelectric pump 15.

First, a sinusoidal AC voltage having a resonance frequency of 15 Vpp is applied to the piezoelectric pump 15, air is sucked from the vacuum source 506, the suction pressure of the air is increased using the regulator 505, and the piezoelectric pump 15 is discharged from the attachment 504. The flow rate of air discharged from the attachment 504 is measured by the flow meter 507 while the pressure of the air to be monitored is monitored by the pressure meter 508. Then, when the pressure measured by the pressure gauge 508 is zero, the flow rate of the air discharged from the attachment 504 (that is, the maximum flow rate) is measured by the flow meter 507 as the discharged flow rate when there is no load.
When measuring the discharge flow rate when the piezoelectric pump 15 alone is not loaded, the fluid control device 100 in FIG. 8 may be replaced with the piezoelectric pump 15 alone.

  FIG. 9 is a diagram comparing the discharge flow rate of the piezoelectric pump 15 alone with no load and the discharge flow rate of the fluid control device 100 with no load.

  From the measurement results shown in FIG. 9, when the discharge flow rate when the piezoelectric pump 15 alone is not loaded is 100%, the discharge flow rate when the fluid control device 100 to which the cover housing 101 is attached is loaded is increased to 270%. It became clear. The reason for this result is that by attaching the cover housing 101, the air flow discharged from the discharge holes 24 is exhausted while drawing the surrounding air existing outside the fluid control device 100 through the air passage 105. This is considered to be due to the discharge from the hole 102 to the outside of the cover housing 101.

  Next, the relationship between the distance between the discharge hole 24 and the discharge hole 102 and the discharge flow rate of the fluid control device 100 at the time of no load will be described. Here, the relationship is such that the discharge flow rate of the fluid control device 100 at no load is Qout, the discharge flow rate of the piezoelectric pump 15 at no load is Qin, the diameter of the discharge hole 24 is D, and the discharge hole 24 and the discharge rate are discharged. When the distance to the hole 102 is L and the proportionality constant is A, it is expressed by the equation Qout / Qin = A√ (L / D).

  FIG. 10 is a diagram showing the relationship between the distance between the discharge hole 24 and the discharge hole 102 and the discharge flow rate of the fluid control device 100 when there is no load. In FIG. 10, the distance between the discharge hole 24 and the discharge hole 102 is changed by fixing the diameter of the discharge hole 102 to a certain length (3.0 mm) and changing the height of the cover housing 101. The result of having measured the flow volume at the time of the no-load of the fluid control apparatus 100 is shown.

  From this measurement result, it became clear that as the distance between the discharge hole 24 and the discharge hole 102 becomes longer, the flow rate of the fluid control device 100 at no load increases. The reason for such a result is that the volume of the air passage 105A increases as the distance between the discharge hole 24 and the discharge hole 102 becomes longer, that is, as the height of the cover housing 101 becomes longer. This is probably because the amount of air that can be increased.

  Next, the relationship between the diameter of the discharge hole 102 in the fluid control apparatus 100 and the discharge flow rate of the fluid control apparatus 100 when there is no load will be described.

  FIG. 11 is a diagram showing the relationship between the diameter of the discharge hole 102 and the discharge flow rate of the fluid control device 100 when there is no load. In FIG. 11, the distance between the discharge hole 24 and the discharge hole 102 is fixed to a certain length (3.2 mm), and the diameter of the discharge hole 102 is changed to change the flow rate of the fluid control device 100 when there is no load. The measurement result is shown.

  From this measurement result, it became clear that as the diameter of the discharge hole 102 becomes longer, the flow rate of the fluid control device 100 at no load increases. In particular, it has been clarified that the flow rate when the fluid control device 100 is unloaded increases from a predetermined flow rate (2.2 mm / L) in a section where the diameter of the discharge hole 102 is 2.0 mm or more.

  From this result, it is considered that the diameter of the discharge hole 102 is preferably 2.0 mm or more. The reason for this result is that the flow of air discharged from the discharge hole 102 while being drawn by the high-speed air flow discharged from the discharge hole 24 as the diameter of the discharge hole 102 becomes longer is covered. This is considered to be because it can be prevented from being blocked by the periphery of the discharge hole 102 in the housing 101.

  From the above, according to the fluid control device 100 of this embodiment, by mounting the cover housing 101, it is small and low-profile, regardless of the capacity (discharge flow rate and discharge pressure) of the piezoelectric pump 15. It became clear that the air flow rate could be increased further.

<Modification>
Embodiments of the present invention can employ the following modifications.

  FIG. 12 is an external perspective view of the fluid control device 200 according to a modification of the embodiment of the present invention when the fluid control device 200 is viewed from the bottom side. 13 is an external perspective view of the cover housing 201 with the piezoelectric pump 15 removed from the fluid control device 200 shown in FIG.

  The fluid control device 200 of this modification is different from the fluid control device 100 of the above-described embodiment in the shape of the cover housing 201 and the mounting method of the fluid control device 200, and the other configurations are the same. For example, the fluid control device 200 blows air from the inside of the casing 10 to the outside of the casing 10. That is, the fluid control device 200 sends warm air existing inside the casing 10 of the electronic device 1 to the outside of the casing 10 through a discharge hole 202 described later, and cools the inside of the casing 10.

  More specifically, as shown in FIGS. 12 and 13, the cover housing 201 is integrally molded with the casing 10 on the inner surface of the casing 10 of the electronic device 1, and the casing 10 is the top plate 104 (FIG. 6). It differs from the cover casing 101 of the above embodiment in that it is replaced with (see). Other configurations are the same. Therefore, the discharge hole 202 is not formed in the cover housing 201, and the discharge hole 202 is formed in the casing 10 of the electronic device 1 as shown in FIG. The discharge hole 202 is the same as the vent hole 11 described above.

  Then, with the upper surface 14 (see FIGS. 5 and 6) of the outer casing 17 of the piezoelectric pump 15 in contact with the mounting surfaces 114 </ b> A to 114 </ b> D of the cover casing 201, screws (not shown) are attached to the cover casing 201. The screw holes 116A to 116D and the screw holes 56A to 56D of the outer casing 17 are fitted.

  Thereby, the piezoelectric pump 15 is attached to the cover housing 201 so that the discharge hole 24 faces the discharge hole 202 (see FIG. 12). Therefore, the cover housing 201 is also detachably attached to the outer housing 17 of the piezoelectric pump 15.

  In this modified example, the air passage 205 </ b> A is formed between the casing 10 and the upper surface 14 of the outer casing 17 of the piezoelectric pump 15 instead of the cover casing 201. Therefore, the airflow discharged from the piezoelectric pump 15 through the discharge hole 24 is discharged from the discharge hole 202 into the casing 10 while drawing air existing outside the fluid control device 200 through the air passage 205A. Therefore, also in this modification, the flow rate of the discharged air increases by the flow rate of the drawn air.

  Also in this modified example, the air passage 205 </ b> A is orthogonal to the central axis connecting the center of the discharge hole 24 and the center of the discharge hole 202. Therefore, the flow of the first air discharged from the discharge hole 24 by the piezoelectric pump 15 and the flow of the second air drawn from the outside of the cover housing 201 through the air passage 205A are orthogonal to each other.

  Here, in order to create the second air flow with the air passage 205A, a length L2 of the air passage 205A (see FIG. 6A) is required to be a predetermined length, but the air passage 205A has the central axis. Therefore, even if the length L2 of the air passage 205A is long, the height of the fluid control device 200 does not increase.

Therefore, according to this modification, the same effects as those of the above-described embodiment can be obtained.
Furthermore, according to the fluid control apparatus 200 of this modified example, since the top plate 104 (see FIG. 6) is not provided, the height can be reduced by the thickness of the top plate 104.

<< Other Embodiments >>
Although air is used as the fluid in the embodiment, the present invention is not limited to this, and the present invention can be applied even if the fluid is a gas other than air.

  Moreover, although the piezoelectric pump is provided in the embodiment, the present invention is not limited to this. For example, an electromagnetic pump that performs a pumping operation by electromagnetic drive may be provided instead of the piezoelectric pump.

  Moreover, in the said embodiment, although the piezoelectric element 40 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 embodiment, the air passage 105A intersects at 90 ° with respect to the central axis connecting the center of the discharge hole 24 and the center of the discharge hole 102. However, the embodiment is not limited to this. For example, the air passage 105A may intersect with the central axis at an angle of approximately 90 ° (89 °, 91 °, etc.).

  Further, the description of the embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above 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 1 ... Electronic device 10 ... Casing 11 ... Vent hole 14 ... Upper surface 15 ... Piezoelectric pump 17 ... Outer housing 18 ... Nozzle 24 ... Discharge hole 31 ... Ventilation path 36 ... Pump chamber 37 ... Top plate 38 ... Side plate 39 ... Vibration plate 40 ... Piezoelectric element 41 ... Spacer 42 ... Cap 45 ... Opening 51 ... Opening area 52 ... Protruding part 53 ... Opening area 55A to 55D ... Notch 56A to 56D ... Screw hole 61 ... Central part 62 ... Protruding part 63, 72 ... External Terminal 70 ... Electrode conduction plate 73 ... Internal terminal 100 ... Fluid control device 101 ... Cover housing 102 ... Discharge hole 104 ... Top plate 105 ... Airflow path 114A-114D ... Mounting surface 116A-116D ... Screw hole 200 ... Fluid control device 201 ... cover housing 202 ... discharge hole 205A ... ventilation path 505 ... regulator 506 ... vacuum source 507 ... channel meter 508 ... pressure gauge 90 , 902, 903 ... air 915 ... cathode chamber 952 ... air supply hole 953 ... air guiding hole AL1 ... air supply passage AP ... air supply pump

Claims (2)

A diaphragm that vibrates flexibly, and an outer peripheral portion of the diaphragm is fixed to form a pump chamber together with the diaphragm, and the inside and outside of the pump chamber communicate with a wall surface of the pump chamber facing the diaphragm. A position where a first air passage is formed between the first housing part in which the opening part to be formed is formed and the first housing part joined to the first housing part, and opposed to the opening part A pump that discharges gas from the discharge hole by the vibration of the diaphragm,
A cover housing that is attached to the second housing portion of the pump and forms a second air passage between the main surface of the second housing portion that is parallel to the diaphragm and opposite to the diaphragm. A fluid control device comprising:
The first air passage and the second air passage communicate with the outside of the fluid control device body,
The cover housing has a discharge hole formed at a position facing the discharge hole via the second air passage,
The fluid control device, wherein the second air passage is orthogonal to a central axis connecting the center of the discharge hole and the center of the discharge hole.   The fluid control device according to claim 1, wherein the cover housing is detachably attached to the second housing portion of the pump.

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