Piezoelectric acceleration transducer

• US 5,631,421 A
• Filed: 11/07/1995
• Issued: 05/20/1997
• Est. Priority Date: 11/10/1994
• Status: Expired due to Term

• Current Assignee: Temic Telefunken Microelectronic GmbH (Continental AG)
• Original Assignee: Temic Telefunken Microelectronic GmbH (Continental AG)
• Inventors: Weinacht, Manfred, Nagele, Dieter, Brinks, Gerald, Ohgke, Thomas, Tiederle, Viktor
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Kwok, Helen C.
• Application Number:
  US08/554,825
• Time in Patent Office: 560 Days
• Field of Search: 73/493, 73/497, 73/514.34, 73/514.38, 73/431, 73/514.35, 73/514.36, 73/514.16, 310/329, 310/330, 310/332, 310/345, 310/348, 310/351, 310/352, 310/353, 310/354
• US Class Current: 73/514.34
• CPC Class Codes: G01P 15/0922 of the bending or flexing mode type

Abstract

A piezoelectric acceleration transducer characterized by a flexible element formed of a piezoelectric material with two external electrodes, a support member having two plate-type supporting components between which the flexible member is arranged, and a carrier plate to which the support member is mechanically and electrically connected such that the principal axis of sensitivity of the flexible element lies in the same plane as the carrier plate. The supporting components may be formed of a nonconducting material with a electrically conductive coating on the side facing the flexible element and at a point of contact with the carrier base. Alternatively, the supporting components may be made from an electrically conductive material.

Claims

1. Piezoelectric acceleration transducer comprising an assembly consisting of a flexible element which is made of a piezoelectric material and is provided with two external electrodes, and which is secured to a support, the assembly being mounted on a carrier plate, wherein:

a) the support consists of two nonconductive, plate-shaped supporting components, between which the flexible element is arranged;

b) the supporting components are connected mechanically to the carrier plate by mechanical points of contact in such a way that a principal axis of sensitivity of the flexible element lies in the same plane as the carrier plate;

c) the two supporting components are each provided with an electrically conductive coating in a respective area of contact with a respective external electrode of the flexible element;

d) to establish an electrical connection with the carrier plate, the electrically conductive coating on each of said supporting components extends to at least one of said mechanical points of contact between the supporting components and the carrier plate; and

e) the mechanical points of contact between the supporting components and the carrier plate are configured as electrical points of contact.

2. Piezoelectric acceleration transducer in accordance with claim 1, wherein each of said supporting components is provided with a bar-shaped component which extends over the flexible element and a supporting foot having a first end connected to the bar-shaped component and a second end having a face, with the second end of the supporting foot being connected to the carrier plate at the mechanical points of contact between the supporting components and the carrier plate.

3. Piezoelectric acceleration transducer in accordance with claim 2, wherein the face of the second end of the supporting foot forms a butt joint with the carrier plate.

4. Piezoelectric acceleration transducer in accordance with claim 3, wherein the mechanical connections between the supporting components and the carrier plate are established by soldering or by an electrically conductive adhesive.

5. Piezoelectric acceleration transducer in accordance with claim 4, wherein the supporting foot is wider than the bar-shaped component.

6. Piezoelectric acceleration transducer in accordance with claim 5, wherein the flexible element is configured as a bimorphous flexible sensor.

7. A piezoelectric acceleration transducer in accordance with claim 1, wherein the flexible element has at least one free end, said free end capable of being deflected under the effect of acceleration forces.

8. A piezoelectric acceleration transducer in accordance with claim 1, wherein the supporting components are located relative to the flexible element such that the flexible element has two free ends, said free ends capable of being deflected under the effect of acceleration forces.

9. Piezoelectric acceleration transducer comprising an assembly consisting of a flexible element which is made of a piezoelectric material and is provided with two external electrodes, and which is secured to a support, the assembly being mounted on a carrier plate, wherein:

a) the support consists of two plate-shaped supporting components, between which the flexible element is arranged;

b) the supporting components are connected mechanically to the carrier plate by points of contact in such a way that a principal axis of sensitivity of the flexible element lies in the same plane as the carrier plate; and

c) the two supporting components are made of an electrically conductive material.

10. Piezoelectric acceleration transducer in accordance with claim 9, wherein each of said supporting components is provided with a bar-shaped component which extends over the flexible element and a supporting foot having a first end connected to the bar-shaped component and a second end having a face, with the second end of the supporting foot being connected to the carrier plate at the points of contact between the supporting components and the carrier plate.

11. Piezoelectric acceleration transducer in accordance with claim 10, wherein the face of the second end of the supporting foot forms a butt joint with the carrier plate.

12. Piezoelectric acceleration transducer in accordance with claim 11, wherein the mechanical connections between the supporting components and the carrier plate are established by soldering or by an electrically conductive adhesive.

13. Piezoelectric acceleration transducer in accordance with claim 12, wherein the supporting foot is wider than the bar-shaped component.

14. Piezoelectric acceleration transducer in accordance with claim 13, wherein the flexible element is configured as a bimorphous flexible sensor.

15. A piezoelectric acceleration transducer in accordance with claim 9, wherein the flexible element has at least one free end, said free end capable of being deflected under the effect of acceleration forces.

16. A piezoelectric acceleration transducer in accordance with claim 9, wherein the supporting components are located relative to the flexible element such that the flexible element has two free ends, said free ends capable of being deflected under the effect of acceleration forces.

17. A piezoelectric acceleration transducer, comprising:

(a) a flexible element formed of a piezoelectric material and having a principal axis of sensitivity and two external electrodes;

(b) a support member having two plate-shaped supporting components made of a nonconducting material between which said flexible element is arranged, each of said supporting components having a first side facing said flexible element, a first end, and a second end opposite said first end;

(c) a carrier plate to which said second end of each of said supporting components is mechanically connected such that the principal axis of sensitivity of said flexible element lies in the same plane as said carrier plate; and

(d) wherein each of said supporting components has an electrically conductive coating on said first side in contact with a respective external electrode of said flexible element and on said second end such that an electrical connection is established between said flexible element and said carrier plate.

18. A piezoelectric acceleration transducer in accordance with claim 17, wherein each of said supporting components has a bar-shaped component extending over said flexible element and a supporting foot having a first end connected to said bar-shaped component and a second end connected to said carrier plate.

19. A piezoelectric acceleration transducer in accordance with claim 17, wherein said flexible element has at least one free end, said free end capable of being deflected under the effect of acceleration forces.

20. A piezoelectric acceleration transducer in accordance with claim 17, wherein the supporting components are located relative to said flexible element such that said flexible element has two free ends, said free ends capable of being deflected under the effect of acceleration forces.