Fluid control device and pump

Patent metadata

Field	Value
Publication number	US-10890171-B2
Application number	US-201916593451-A
Country	US
Kind code	B2
Filing date	Oct 4, 2019
Priority date	Feb 21, 2014
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

A pump ( 1 ) includes a vibrating plate ( 15 ) that has a central part ( 21 ), a frame part ( 22 ), and connecting parts ( 23 to 26 ), a piezoelectric element ( 16 ) that is stacked over the central part ( 21 ) and configured to cause flexural vibrations to occur concentrically from the central part ( 21 ) to the connecting parts ( 23 to 26 ), and an opposed plate ( 13 ) that is stacked over the frame part ( 22 ) and positioned facing each of the connecting parts ( 23 to 26 ) with a spacing therebetween. The vibrating plate ( 15 ) has such a resonant mode that an antinode occurs in each of the central part ( 21 ) and the connecting parts ( 23 to 26 ). The opposed plate ( 13 ) has, at positions facing the connecting parts ( 23 to 26 ), a plurality of channel holes ( 39 to 43 ) through which a fluid flows.

First claim

The invention claimed is:

1. A fluid control device comprising:
an inlet for sucking fluid from an external space into the fluid control device,
an outlet for discharging the fluid from within the fluid control device to the external space,
a vibrating plate having a circular central part, a frame part surrounding the circular central part, and a plurality of connecting parts connecting between the circular central part and the frame part, the plurality of connecting parts being located along a circle that is concentric with the circular central part;
a driver stacked over the circular central part, the driver being configured to vibrate the vibrating plate in a flexural manner from the circular central part to the plurality of connecting parts; and
an opposed plate stacked over the frame part, the opposed plate being spaced apart from and opposed to at least the plurality of connecting parts,
wherein the opposed plate has a plurality of channel holes through which a fluid flows, each of the channel holes being located at a position opposed to a respective connecting part of the plurality of connecting parts, and
wherein during operation of the fluid control device, the fluid is sucked through the inlet, flows through the plurality of channel holes, and is discharged through the outlet.

2. The fluid control device according to claim 1 ,
wherein the vibrating plate has a plurality of openings defined by the plurality of connecting parts, the circular central part, and the frame part.

3. The fluid control device according to claim 1 ,
wherein each connecting part of the plurality of connecting parts includes, at a position opposed to a respective channel hole of the plurality of channel holes, a striking part having a width that is locally increased as viewed from the respective channel hole.

4. The fluid control device according to claim 1 ,
wherein each connecting part of the plurality of connecting parts includes, at a position opposed to a respective channel hole of the plurality of channel holes, a projection that projects toward the respective channel hole.

5. The fluid control device according to claim 1 ,
wherein the opposed plate includes, around each of the plurality of channel holes, a projection projecting toward the vibrating plate.

6. The fluid control device according to claim 1 ,
wherein the opposed plate includes a movable part that is bendable and provided around each of the plurality of channel holes, and a restraining part restraining an area around the movable part.

7. The fluid control device according to claim 6 ,
wherein the movable part has a shape in a plan view having a major axis extending in a direction of producing antinodes uniformly in the plurality of connecting parts, and a minor axis extending in a direction orthogonal to the major axis.

8. The fluid control device according to claim 6 , further comprising a channel part stacked over a side of the opposed plate opposite to the vibrating plate, the channel part having:
a plurality of channels communicating with the plurality of channel holes of the opposed plate, each channel including an opening and an extension extended laterally from the opening, the opening being opposed to a respective channel hole of the plurality of channel holes and an area around the respective channel hole, and
a plurality of holes opened to the external space each hole communicating with a respective opening of the channels through the extension extended laterally from the respective opening.

9. The fluid control device according to claim 8 ,
wherein at least one of the channel part and the opposed plate has a coefficient of linear expansion substantially equal to a coefficient of linear expansion of the vibrating plate.

10. The fluid control device according to claim 1 ,
wherein the opposed plate is stacked over the vibrating plate by using an adhesive, and
wherein the opposed plate has an opening that extends along an inner boundary of the frame part of the vibrating plate.

11. The fluid control device according to claim 1 ,
wherein the vibrating plate and the opposed plate are each made of an electrically conductive material,
wherein the opposed plate and the vibrating plate are stacked by using an adhesive containing electrically conductive particles, and
wherein the electrically conductive particles have a particle diameter equivalent to a spacing between the opposed plate and the vibrating plate.

12. The fluid control device according to claim 1 , further comprising:
an insulating layer stacked over the frame part, the insulating layer being positioned over a side of the vibrating plate over which the driver is stacked; and
a power feeding plate stacked over the vibrating plate with the insulating layer interposed between the power feeding plate and the vibrating plate, the power feeding plate having an internal connection terminal formed in a part of the power feeding plate, the internal connection terminal being connected to the driver.

13. The fluid control device according to claim 12 ,
wherein the insulating layer includes an insulating coating located between the vibrating plate and the power feeding plate.

14. The fluid control device according to claim 12 ,
wherein the insulating layer includes an adhesive mixed with non-electrically conductive particles.

15. The fluid control device according to claim 12 , further comprising a metal plate stacked over the frame part of the vibrating plate.

16. The fluid control device according to claim 12 ,
wherein the frame part of the vibrating plate has a groove located on a side of the vibrating plate over which the driver is stacked, and
wherein the insulating layer and the power feeding plate are disposed in the groove.

17. The fluid control device according to claim 1 ,
wherein the opposed plate has an additional channel hole at a position facing the circular central part.

18. The fluid control device according to claim 1 , further comprising a stacking plate further stacked over the vibrating plate and the driver,
wherein the vibrating plate, the driver, and the stacking plate form three layers, the three layers being an upper layer, a middle layer, and a lower layer, and a magnitude relationship of a coefficient of linear expansion of the middle layer with respect to a coefficient of linear expansion of the upper layer is identical to a magnitude relationship of the coefficient of linear expansion of the middle layer with respect to a coefficient of linear expansion of the lower layer.

19. The fluid control device according to claim 18 ,
wherein among the three layers including the vibrating plate, the driver, and the stacking plate, a component corresponding to a layer in contact with the driver has a coefficient of linear expansion greater than a coefficient of linear expansion of the driver.

20. The fluid control device according to claim 1 ,
wherein the opposed plate includes a first opposed plate and a second opposed plate, the first opposed plate being disposed facing one principal face of the vibrating plate, the second opposed plate being disposed facing another principal face of the vibrating plate.

21. The fluid control device according to claim 1 , wherein the driver includes a first driver and a second driver, the first driver being disposed facing one principal face of the vibrating plate, the second driver being disposed facing another principal face of the vibrating plate.

22. A pump comprisi

Assignees

• Murata Manufacturing Co

Inventors

• Hirata Atsuhiko
• Kodama Yukiharu

Classifications

• F04B43/04 Primary

  Pumps having electric drive · CPC title

• Y02E60/50

  Fuel cells · CPC title

• F04B43/046 Primary

  with piezoelectric drive · CPC title

• F04B43/14

  having plate-like flexible members · CPC title

• F04B45/047

  Pumps having electric drive · CPC title