Piezoelectric device with amplifying mechanism

• US 7,227,295 B2
• Filed: 02/04/2005
• Issued: 06/05/2007
• Est. Priority Date: 02/04/2005
• Status: Active Grant

• Current Assignee: ASM Assembly Automation Limited (ASMPT Ltd.)
• Original Assignee: ASM Assembly Automation Limited (ASMPT Ltd.)
• Inventors: Liu, Chou Kee Peter, Choy, Ping Kong Joseph, Chan-Wong, Lai Wa Helen, Or, Siu Wing, Yung, Chung Shueng
• Primary Examiner(s): Dougherty; Tom
• Assistant Examiner(s): ADDISON, KAREN B
• Application Number:
  US11/051,091
• Publication Number:
  US 20060175934A1
• Time in Patent Office: 851 Days
• Field of Search: 310/328, 310330-332, 310/369, 310/325, 310/311, 310/337, 367/167
• US Class Current: 310/328
• CPC Class Codes: H02N 2/028 along multiple or arbitrary translation directions, e.g. XYZ stages
• CPC Class Codes: H02N 2/043 Mechanical transmission means, e.g. for stroke amplification
• CPC Class Codes: H10N 30/2043 connected at their free ends, e.g. parallelogram type

Abstract

A piezoelectric device is provided that comprises a mechanical amplifier adapted to produce a displacement output and/or receive a force input, and first and second flexible platforms connected to the mechanical amplifier. The first flexible platform is connected to one side of the mechanical amplifier and piezoelectric material is mounted on the first flexible platform for controllably flexing the first flexible platform. The second flexible platform is connected to another side of the mechanical amplifier and piezoelectric material is mounted to the second flexible platform for controllably flexing the second flexible platform.

Claims

1. Piezoelectric device comprising:

a mechanical amplifier adapted to produce a displacement output and/or receive a force input;

a first flexible platform connected to one side of the mechanical amplifier;

piezoelectric material mounted on the first flexible platform for controllably flexing the first flexible platform;

a second flexible platform connected to another side of the mechanical amplifier; and

piezoelectric material mounted to the second flexible platform for controllably flexing the second flexible platform.

2. Piezoelectric device as claimed in claim 1, wherein the first flexible platform and second flexible platform are arranged on opposite sides of the mechanical amplifier and are positioned symmetrically with respect to each other about the mechanical amplifier.

3. Piezoelectric device as claimed in claim 2, including a third flexible platform and a fourth flexible platform connected to the mechanical amplifier, and piezoelectric material mounted on the third and fourth flexible platforms for controllably flexing the third and fourth platforms, wherein each of the third and fourth flexible platforms are arranged orthogonally with respect to the first and second flexible platforms.

4. Piezoelectric device as claimed in claim 1, wherein the flexible platforms are inclined at an oblique angle with respect to the mechanical amplifier.

5. Piezoelectric device as claimed in claim 1, wherein the piezoelectric materials are drivable by an electrical signal to impart stress to flex the first and second flexible platforms and move the mechanical amplifier connected to the first and second flexible platforms.

6. Piezoelectric device as claimed in claim 1, wherein an external force is receivable by the mechanical amplifier so as to deform the first and second flexible platforms and apply stress on the piezoelectric materials, whereby the piezoelectric materials are responsive to said stress to generate electrical signals through which said external force is measurable.

7. Piezoelectric device as claimed in claim 1, wherein the mechanical amplifier comprises amplifying levers connected to the flexible platforms, a central seat adapted to deliver a displacement output and/or receive a force input, and flexural links linking the amplifying levers to the central seat.

8. Piezoelectric device as claimed in claim 7, wherein the amplifying levers are arranged substantially orthogonally to the flexural links, and the flexural links are arranged substantially orthogonally to the central seat.

9. Piezoelectric device as claimed in claim 7, including mounting means located on the central seat.

10. Piezoelectric device as claimed in claim 1, wherein the mechanical amplifier consists of a monolithic high-strength metallic material.

11. Piezoelectric device as claimed in claim 10, wherein the mechanical amplifier is made from a material selected from the group consisting of:

stainless steels, titanium alloys and aluminum alloys.

12. Piezoelectric device as claimed in claim 10, wherein the flexible platforms are formed from the same piece of monolithic high-strength metallic material comprising the mechanical amplifier.

13. Piezoelectric device as claimed in claim 1, including mounting flanges located on a side of the first flexible platform and on a side of the second flexible platform for mounting the piezoelectric device to a structure.

14. Piezoelectric device as claimed in claim 1, wherein the mechanical amplifier includes a central portion that is located on a plane, and energizing the piezoelectric materials is operative to selectively move the central portion to displace it axially, rotate it and tilt it with respect to the plane.

15. Piezoelectric device as claimed in claim 1, including multiple layers of piezoelectric material mounted onto the flexible platforms.

16. Piezoelectric device as claimed in claim 15, wherein the multiple layers of piezoelectric material are mounted onto opposite surfaces of each flexible platform.

17. Piezoelectric device as claimed in claim 1, wherein a central portion of each of the first and second flexible platforms comprises an elongated slot dividing each flexible platform, and each divided part of each flexible platform is adapted to individually mount piezoelectric material and is independently flexible with respect to an adjacent divided part of the flexible platform.

18. Piezoelectric device as claimed in claim 1, including another piezoelectric device that is substantially similar to said piezoelectric device and coupled to the piezoelectric device, wherein both piezoelectric devices are configured to be drivable simultaneously.

19. Piezoelectric device as claimed in claim 18, wherein the mechanical amplifiers of the piezoelectric devices are configured to be drivable simultaneously in identical directions for increasing force output.

20. Piezoelectric device as claimed in claim 19, further comprising a transmission column inserted between the mechanical amplifiers of both piezoelectric devices.

21. Piezoelectric device as claimed in claim 18, wherein the mechanical amplifiers of the piezoelectric devices are configured to be drivable simultaneously in opposite directions for increasing displacement output.

22. Piezoelectric device as claimed in claim 18, including an object coupled between the two piezoelectric devices to the mechanical amplifiers of the piezoelectric devices whereby the piezoelectric devices are configured to drive the object along a first axis.

23. Piezoelectric device as claimed in claim 22, further comprising a third piezoelectric device and a fourth piezoelectric device arranged such that the object is coupled between the third and fourth piezoelectric devices to the mechanical amplifiers of the third and fourth piezoelectric devices, whereby the third and fourth piezoelectric devices are configured to drive the object relative to the third and fourth piezoelectric devices along a second axis that is orthogonal to the first axis.