PIEZOELECTRIC ACTUATOR, MOTOR, ROBOT HAND, AND ROBOT

• US 20120248805A1
• Filed: 03/27/2012
• Published: 10/04/2012
• Est. Priority Date: 03/29/2011
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: KAMIJO, Koichi, MIYAZAWA, Osamu, SAWADA, Akihiro, NAGAHAMA, Reiko
• Granted Patent: US 8,525,387 B2
• Time in Patent Office: Days
• US Class Current: 294/213
• CPC Class Codes: B25J 15/0009 comprising multi-articulated fingers, e.g. resembling a human hand
• CPC Class Codes: H02N 2/001 Driving devices, e.g. vibrators
• CPC Class Codes: H02N 2/004 Rectangular vibrators
• CPC Class Codes: H02N 2/103 by pressing one or more vibrators against the rotor
• CPC Class Codes: H02N 2/22 Methods relating to manufacturing, e.g. assembling, calibration
• CPC Class Codes: H10N 30/20 with electrical input and mechanical output, e.g. functioning as actuators or vibrators
• CPC Class Codes: Y10S 901/38 Electric motor
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

A motor includes a vibrating plate having a projection part to be pressed against a driven member and a piezoelectric material provided on the vibrating plate, wherein a Young'"'"'s modulus E_L in the pressing direction of the vibrating plate and a Young'"'"'s modulus E_S in a direction crossing the pressing direction are different.

Claims

1. A piezoelectric actuator at least comprising:

a vibrating plate having a projection part to be urged toward a driven member at an end; and

a piezoelectric material stacked on the vibrating plate,

wherein a Young'"'"'s modulus E_L in the urging direction of the vibrating plate and a Young'"'"'s modulus E_S in an intersection direction crossing the urging direction are different.

2. The piezoelectric actuator according to claim 1, wherein the vibrating plate is formed by a plate-like base material formed by a rolling method.

3. The piezoelectric actuator according to claim 1, wherein values of the Young'"'"'s modulus E_L and the Young'"'"'s modulus E_S satisfy the following relationship:

E_L>

E_S.

4. The piezoelectric actuator according to claim 1, wherein the piezoelectric material is lead zirconate titanate (PZT).

5. A motor comprising:

the piezoelectric actuator according to claim 1;

a driven member driven by the piezoelectric actuator; and

an urging unit that urges the piezoelectric actuator toward the driven member.

6. A motor comprising:

the piezoelectric actuator according to claim 2;

a driven member driven by the piezoelectric actuator; and

an urging unit that urges the piezoelectric actuator toward the driven member.

7. A motor comprising:

the piezoelectric actuator according to claim 3;

a driven member driven by the piezoelectric actuator; and

an urging unit that urges the piezoelectric actuator toward the driven member.

8. A motor comprising:

the piezoelectric actuator according to claim 4;

a driven member driven by the piezoelectric actuator; and

an urging unit that urges the piezoelectric actuator toward the driven member.

9. A robot hand comprising the motor according to claim 5.

10. A robot hand comprising the motor according to claim 6.

11. A robot hand comprising the motor according to claim 7.

12. A robot hand comprising the motor according to claim 8.

13. A robot comprising the robot hand according to claim 9.

14. A robot comprising the robot hand according to claim 10.

15. A robot comprising the robot hand according to claim 11.

16. A robot comprising the robot hand according to claim 12.

17. A motor comprising:

a vibrating plate having a projection part;

a piezoelectric material provided on the vibrating plate;

a driven part driven by vibration of the projection part in contact with the projection part; and

an urging unit that urges the vibrating plate toward the driven part,

wherein a Young'"'"'s modulus E_L of the vibrating plate in the urging direction and Young'"'"'s modulus E_S of the vibrating plate in a direction crossing the urging direction are different.

18. A robot comprising:

a vibrating plate having a projection part;

a piezoelectric material provided on the vibrating plate;

a driven part driven by vibration of the projection part in contact with the projection part;

an urging unit that urges the vibrating plate toward the driven part; and

plural finger parts that grasp an object,

wherein a value of a Young'"'"'s modulus E_L of the vibrating plate in the urging direction and a value of a Young'"'"'s modulus E_S of the vibrating plate in a direction crossing the urging direction are different in magnitude.

19. The robot according to claim 18, wherein the value of the Young'"'"'s modulus E_L is larger than the value of the Young'"'"'s modulus E_S.