Piezoelectric actuator module, and method for assembling a piezoelectric actuator module

• US 7,183,695 B2
• Filed: 06/06/2003
• Issued: 02/27/2007
• Est. Priority Date: 07/20/2002
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Kienzler, Dieter, Uhlmann, Dietmar, Loutrage, Jean-Luc
• Primary Examiner(s): Dougherty; Thomas M.
• Application Number:
  US10/509,590
• Publication Number:
  US 20050162046A1
• Time in Patent Office: 1,362 Days
• Field of Search: 310/328, 310/348, 123/445, 123/446, 251/129.06, 239/102.2
• US Class Current: 310/328
• CPC Class Codes: F02M 2200/16 Sealing of fuel injection apparatus not otherwise provided for
• CPC Class Codes: F02M 47/027 Electrically actuated valves draining the chamber to release the closing pressure
• CPC Class Codes: F02M 61/167 Means for compensating clearance or thermal expansion
• CPC Class Codes: F02M 63/0026 using piezoelectric or magnetostrictive actuators
• CPC Class Codes: H10N 30/88 Mounts; Supports; Enclosures; Casings

Abstract

A piezoelectric actuator module having at least one piezoelectric component, one actuator foot, and one actuator head is surrounded by an axially extending bush. For sealing the piezoelectric actuator module in the axial direction, the actuator foot is adjoined by a diaphragm, which extends essentially in the radial direction, is joined to the bush, and has a cross section with various radii of curvature.

Claims

1. A piezoelectric actuator module, comprising

at least one piezoelectric component (6), one actuator foot (5), and one actuator head (7) which head includes a conical portion, (42) and cooperates with a component to be actuated by the piezoelectric component (6),

a bush (9) extending in the axial direction and surrounding the actuator module (2;

20;

30), and

a diaphragm (10;

21;

31;

41) extending essentially in the radial direction and adjoining the actuator head (7), the diaphragm being connected to the conical portion,

the diaphragm (10;

21;

31;

41) also being joined to the bush (9) and having a curved cross section in the radial direction.

2. The piezoelectric actuator module of claim 1, wherein the diaphragm (10;

21;

31;

41) is welded to the actuator head (7).

3. The piezoelectric actuator module of claim 1, wherein the diaphragm (10;

21;

41) is welded to the bush (9).

4. The piezoelectric actuator module of claim 2, wherein the diaphragm (10;

21;

41) is welded to the bush (9).

5. The piezoelectric actuator module of claim 1, wherein the diaphragm (31) is manufactured integrally with the bush (9).

6. The piezoelectric actuator module of claim 2, wherein the diaphragm (31) is manufactured integrally with the bush (9).

7. The piezoelectric actuator module of claim 1, wherein the curved cross section of the diaphragm has different radii of curvature.

8. The piezoelectric actuator module of claim 2, wherein the curved cross section of the diaphragm has different radii of curvature.

9. The piezoelectric actuator module of claim 5, wherein the curved cross section of the diaphragm has different radii of curvature.

10. The piezoelectric actuator module of claim 1, wherein the diaphragm (10;

21;

31;

41) has a thickness of between approximately 70 μ

m and 200 μ

m.

11. The piezoelectric actuator module of claim 2, wherein the diaphragm (10;

21;

31;

41) has a thickness of between approximately 70 μ

m and 200 μ

m.

12. The piezoelectric actuator module of claim 3, wherein the diaphragm (10;

21;

31;

41) has a thickness of between approximately 70 μ

m and 200 μ

m.

13. The piezoelectric actuator module of claim 5, wherein the diaphragm (10;

21;

31;

41) has a thickness of between approximately 70 μ

m and 200 μ

m.

14. The piezoelectric actuator module of claim 6, wherein the diaphragm (10;

21;

31;

41) has a thickness of between approximately 70 μ

m and 200 μ

m.

15. The piezoelectric actuator module of claim 7, wherein the diaphragm (10;

21;

31;

41) has a thickness of between approximately 70 μ

m and 200 μ

m.

16. The piezoelectric actuator module of claim 1, installed as a triggering unit of a fuel injection valve (1) of a motor vehicle.

17. A method for installing a piezoelectric actuator module, which includes at least one piezoelectric component (6), one actuator foot (5) and one actuator head (7), which head has a conical portion (42) and cooperates with a component to be actuated by the piezoelectric component (6), and the actuator module (2;

20;

30;

40) is surrounded by a bush (9) extending in the axial direction, the method comprising closing the bush on its face end, on the side toward the actuator head (7), by means of a diaphragm (10;

21;

31;

41) which is secured to the conical portion (42), and which extends essentially in the radial direction.

18. The method of claim 17, further comprising welding the diaphragm (41) and the actuator head (7) together in load-free fashion.

19. The method of claim 18, further comprising introducing the actuator head (7), which has been welded to the diaphragm (41), into the bush (9), and subjecting the actuator head to a preload in the direction of the piezoelectric component (6).

20. The method of claim 19, further comprising welding the diaphragm (41) to the bush (9) with the actuator head (7) preloaded.