Piezoelectric actuator and piezoelectric actuating plate thereof

Patent metadata

Field	Value
Publication number	US-11342494-B2
Application number	US-201815973976-A
Country	US
Kind code	B2
Filing date	May 8, 2018
Priority date	May 12, 2017
Publication date	May 24, 2022
Grant date	May 24, 2022

Abstract

A piezoelectric actuator for a miniature fluid transportation device is provided and includes a piezoelectric actuating plate and a piezoelectric element. The piezoelectric actuating plate includes a suspension plate, an outer frame, and brackets. The suspension plate has a first thickness. The outer frame is arranged around the suspension plate and has a third thickness. Each of the brackets is connected between the suspension plate and the outer frame and has a fourth thickness. The third thickness is larger than the first thickness, and the first thickness is larger than the fourth thickness. The suspension plate, the outer frame and the brackets are constructed to form different stepped structures to minimize the thickness of the brackets, enhance the elasticity of the brackets. Thus, displacement of the suspension plate in the vertical direction is enhanced and the transportation efficiency of the miniature fluid transportation device is intensified.

First claim

What is claimed is:

1. A piezoelectric actuator for a miniature fluid transportation device, comprising:
a piezoelectric actuating plate comprising:
a suspension plate having a top surface and an opposing bottom surface, wherein a bulge with a bulging surface is formed on the top surface of the suspension plate, wherein a first thickness is defined between the top surface of the suspension plate and the bottom surface of the suspension plate, and a second thickness is defined between the bulging surface and the bottom surface of the suspension plate;
an outer frame arranged around the suspension plate and comprising a top surface and an opposing bottom surface, wherein a third thickness is defined between the top surface of the outer frame and the bottom surface of the outer frame;
at least one bracket connected between the suspension plate and the outer frame, comprising a top surface and an opposing bottom surface, wherein a fourth thickness is defined between the top surface of the at least one bracket and the bottom surface of the at least one bracket; and
at least one recess arranged nearby the at least one bracket and comprising a recessed surface; and
a piezoelectric element attached on the bottom surface of the suspension plate;

wherein the third thickness is larger than the first thickness, and the first thickness is larger than the fourth thickness.

2. The piezoelectric actuator according to claim 1 , wherein the third thickness is equal to the second thickness.

3. The piezoelectric actuator according to claim 1 , wherein the bulging surface of the bulge and the top surface of the outer frame are coplanar, the recessed surface of the at least one recess and the top surface of the at least one bracket are coplanar, and the bottom surface of the suspension plate, the bottom surface of the at least one bracket and the bottom surface of the outer frame are coplanar.

4. The piezoelectric actuator according to claim 3 , wherein the top surface of the suspension plate, the top surface of the at least one bracket and the recessed surface of the at least one recess are configured to form a stepped structure with a coplanar surface by etching.

5. The piezoelectric actuator according to claim 1 , wherein the bulging surface of the bulge and the top surface of the outer frame are coplanar, the recessed surface of the at least one recess and the top surfaces of the at least one bracket and the suspension plate are coplanar, and the bottom surface of the suspension plate and the bottom surface of the outer frame are coplanar.

6. The piezoelectric actuator according to claim 5 , wherein the top surface of the suspension plate, the top surface of the at least one bracket and the recessed surface of the at least one recess are formed by etching to be non-coplanar with each other and to form a stepped-up and stepped-down structure.

7. The piezoelectric actuator according to claim 1 , wherein the third thickness is ranged from 295 μm to 305 μm.

8. The piezoelectric actuator according to claim 1 , wherein the first thickness is ranged from 265 μm to 275 μm.

9. The piezoelectric actuator according to claim 1 , wherein the fourth thickness is ranged from 250 μm to 260 μm.

10. A piezoelectric actuating plate for a piezoelectric actuator of a miniature fluid transportation device, the piezoelectric actuating plate comprising:
a suspension plate having a top surface and an opposing bottom surface, wherein a bulge with a bulging surface is formed on the top surface of the suspension plate, wherein a first thickness is defined between the top surface of the suspension plate and the bottom surface of the suspension plate, and a second thickness is defined between the bulging surface and the bottom surface of the suspension plate;
an outer frame arranged around the suspension plate and comprising a top surface and an opposing bottom surface, wherein a third thickness is defined between the top surface of the outer frame and the bottom surface of the outer frame;
at least one bracket connected between the suspension plate and the outer frame, comprising a top surface and an opposing bottom surface, wherein a fourth thickness is defined between the top surface of the bracket and the bottom surface of the bracket; and
at least one recess arranged nearby the at least one bracket and comprising a recessed surface;
wherein the third thickness is larger than the first thickness, and the first thickness is larger than the fourth thickness.

11. The piezoelectric actuating plate according to claim 10 , wherein the third thickness is equal to the second thickness.

12. The piezoelectric actuating plate according to claim 10 , wherein the bulging surface of the bulge and the top surface of the outer frame are coplanar, the recessed surface of the at least one recess and the top surface of the at least one bracket are coplanar, and the bottom surface of the suspension plate, the bottom surface of the at least one bracket and the bottom surface of the outer frame are coplanar to form a coplanar bottom surface.

13. The piezoelectric actuating plate according to claim 12 , wherein the top surface of the suspension plate, the top surface of the at least one bracket and the recessed surface of the at least one recess are formed by etching to be a stepped structure with the coplanar bottom surface.

14. The piezoelectric actuating plate according to claim 10 , wherein the bulging surface of the bulge and the top surface of the outer frame are coplanar, the recessed surface of the at least one recess and the top surfaces of the at least one bracket and the suspension plate are coplanar, and the bottom surface of the suspension plate and the bottom surface of the outer frame are coplanar.

15. The piezoelectric actuating plate according to claim 14 , wherein the top surface of the suspension plate, the top surface of the at least one bracket and the recessed surface of the at least one recess are formed by etching to be non-coplanar with each other and to form a stepped-up and stepped-down structure with non-coplanar surfaces.

16. The piezoelectric actuating plate according to claim 10 , wherein the third thickness is ranged from 295 μm to 305 μm.

17. The piezoelectric actuating plate according to claim 10 , wherein the first thickness is ranged from 265 μm to 275 μm.

18. The piezoelectric actuating plate according to claim 10 , wherein the fourth thickness is ranged from 250 μm to 260 μm.

Assignees

• Microjet Technology Co Ltd

Inventors

• Liao Hung-Hsin
• Chen Shih-Chang
• Liao jia-yu
• Han Yung-Lung
• Lee Wei-Ming

Classifications

• F15B5/006

  with electrical means, e.g. electropneumatic transducer (F15B5/003 takes precedence) · CPC title

• H01L41/053

  Electricity · mapped topic

• H01L41/313

  Electricity · mapped topic

• H01L41/0973

  Electricity · mapped topic

• H01L41/098 Primary

  Electricity · mapped topic