ANNULAR SHEAR ACCELEROMETER

• US 3,612,921 A
• Filed: 03/27/1969
• Issued: 10/12/1971
• Est. Priority Date: 03/27/1969
• Status: Expired due to Term

• Current Assignee: Bell & Howell LLC (Böwe Systec AG)
• Original Assignee: Dan L. Springate
• Inventors: Springate, Dan L.
• Primary Examiner(s): Hirshfield, Milton O.
• Assistant Examiner(s): Budd, Mark O.
• Application Number:
  US04/811,120
• Time in Patent Office: 929 Days
• Field of Search: 310/8.2-8.6,9.1-9.4 340/17 73/71,517
• US Class Current: 310/329
• CPC Class Codes: G01P 15/0915 of the shear mode type

Abstract

A shear accelerometer characterized by its clamping means securing an annular piezoelectric element to both the accelerometer'"'"''"'"'s base and inertial members, thereby avoiding the utilization of interfacial bonding media.

Claims

1. In a transducer having a longitudinal axis, the combination comprising:

an annular piezoelectric element having first and second flat faces each including inner and outer circumferential portions perpendicular to and concentric about said axis;

a first member clamped to said element along said inner circumferential portions; and

a second member clamped to said element along said outer circumferential portions;

said members being axially movable relative to one another for producing shear mode strains in said element.

2. The transducer according to claim 1, above, further including electrode means conductively coupled to said element and responsive to electrical charges generated by said element in response to shear mode strains produced therein.

3. In a transducer having a longitudinal axis, the combination comprising:

an annular piezoelectric element having first and second flat faces each including inner and outer circumferential portions perpendicular to and concentric about said axis;

a first member;

clamping means rigidly coupling said inner circumferential portions to said first member;

a second member;

clamping means rigidly coupling said outer circumferential portions to said second member;

said members being axially movable relative to one another for producing shear mode strains in said piezoelectric element.

4. The transducer according to claim 3, above, further including electrode means conductively coupled to said element and responsive to electrical charges generated by said element in response to shear mode strains produced therein.

5. The transducer according to claim 3, above, wherein said element is radially polarized, and further including a first electrode in conductive contact with said first face and a second electrode in conductive contact with said second face.

6. In an accelerometer having a longitudinal axis, the combination comprising:

an annular piezoelectric element having first and second flat faces each including inner and outer circumferential portions perpendicular to and concentric about said axis;

a base member having a cylindrical pedestal portion concentric about said axis and supporting said element along said second face inner circumferential portion;

means cooperating with said base member and said first face inner circumferential portion for axially coercing said second face inner circumferential portion toward said pedestal portion;

an inertial member encircling said element and clamped thereto along said outer circumferential portions.

7. The accelerometer according to claim 6, above, wherein said element is radially polarized, and further including first electrode means on said first flat face, and second electrode means on said second flat face.

8. The accelerometer according to claim 6, above, wherein said element is radially polarized, and further including first electrode means on said first flat face, and second electrode means on said second flat face and conductively communicating with said base member.

9. The accelerometer according to claim 6, above, wherein said element is radially polarized, and further including first electrode means on said first flat face, and second electrode means on said second flat face and conductively communicating with said inertial member.

10. The accelerometer according to claim 6, above, wherein said inertial member includes an annular member encircling said element and having a colLar portion overlapping said first face outer circumferential portion, and a retainer ring member overlapping said second face outer circumferential portion and rigidly secured to said annular member, said collar and ring portions coercing said outer circumferential portions toward one another.