Angle and angular acceleration sensors

• US 5,546,805 A
• Filed: 08/12/1994
• Issued: 08/20/1996
• Est. Priority Date: 08/12/1994
• Status: Expired due to Fees

• Current Assignee: Coyote Engineering Services, Inc.
• Original Assignee: Coyote Engineering Services, Inc.
• Inventors: Swartz, Harold L., Anderson, Jane E.
• Primary Examiner(s): Williams, Hezron E.
• Assistant Examiner(s): MOLLER, RICHARD ALAN
• Application Number:
  US08/289,636
• Time in Patent Office: 739 Days
• Field of Search: 73/517 A, 73/517 B, 73/517 R, 73/514.02, 73/514.32, 73/652, 73/514.01, 33/366, 361/280, 361/281, 257/419
• US Class Current: 73/514.02
• CPC Class Codes: G01P 15/0888 for indicating angular acceleration
• CPC Class Codes: G01P 15/125 by capacitive pick-up

Abstract

Angle and angular acceleration sensors are fabricated as a layered sandwich structure having a central sensing plate, left and right insulating spacers positioned outside the sensing plate, left and right driver plates positioned outside the insulating spacers, and left and right molded plastic housing shells positioned outside the driver plates for sealing the sensor structure. In an angle sensor embodiment of the invention, the sensing plate includes a peripheral frame and a central plate area mechanically connected to one side of the peripheral frame by way of a pair of beams that serve as a hinge to allow the central plate area of the sensing plate to rotate toward and away from the driver plates sandwiched on either side thereof. In an angular acceleration sensor embodiment of the invention, the sensing plate includes a peripheral frame and a central plate area divided into upper and lower halves, each of which is mechanically connected to the frame by way of a pair of beams that extend inwardly from two opposite sides of the frame and that similarly serve as a hinge to allow the upper and lower halves of the central plate to rotate toward and away from the adjacent driver plates.

Claims

1. An angle sensor formed as a layered sandwich structure of rectangularly-shaped elements, comprising:

a metallic central sensing plate;

left and right spacers positioned on either side of said central sensing plate;

left and right driver plates positioned outside said left and right spacers, respectively; and

electrical connection means for electrically connecting said central sensing plate and said left and right driver plates to external angle measurement circuitry;

said central sensing plate comprising a peripheral frame and a central plate area, the central plate area being uniformly spaced away from the peripheral frame along the entirety of top and bottom edges of the central plate area and being uniformly spaced away from the peripheral frame along substantially the entirety of left and right edges of the central plate area, the central plate area being connected to the peripheral frame only by way of a pair of axially aligned torsion bars, each of the torsion bars extending inwardly at the top edge of the central plate area from left and right inner edges, respectively, of the peripheral frame to allow the central plate area to rotate toward and away from said driver plates when said angle sensor is tilted with respect to the axis of the pair of torsion bars.

2. An angle sensor as in claim 1, further comprising left and right housing shells positioned outside said left and right driver plates, respectively, for sealing said angle sensor.

3. An angle sensor as in claim 1, wherein said left and right spacers and said left and right driver plates are fabricated of materials chosen to electrically insulate said central sensing plate from said left and right driver plates.

4. An angle sensor as in claim 3, wherein:

said central sensing plate comprises beryllium copper;

said left and right driver plates comprise brass; and

said left and right spacers comprise an electrical insulator.

5. An angle sensor as in claim 2, wherein said left and right housing shells comprise a molded plastic material.

6. An angle sensor as in claim 1, wherein said electrical connection means comprises an electrical connection tab extending from each of said central sensing plate and said left and right driver plates.

7. An angular acceleration sensor formed as a layered sandwich structure of rectangularly-shaped elements, comprising:

a metallic central sensing plate;

left and right spacers positioned on either side of said central sensing plate;

left and right driver plates positioned outside said left and right spacers, respectively, each of said left and right driver plates being divided into upper and lower driver plate areas;

spacers, respectively; and

electrical connection means for electrically connecting said central sensing plate and said left and right driver plates to external angular acceleration measurement circuitry;

said central sensing plate comprising a peripheral frame and a central plate area, the central plate area being uniformly spaced away from the peripheral frame along the entirety of top and bottom edges of the central plate area and being uniformly spaced away from the peripheral frame along substantially the entirety of left and right edges of the central plate area, the central plate area being connected to the peripheral frame only by way of a pair of axially aligned torsion bars, each of the torsion bars extending inwardly from left and right inner edges, respectively, of the peripheral frame at points midway along the left and right inner edges of the peripheral frame to divide the central plate area into upper and lower central plate areas to allow the upper and lower central plate areas to rotate toward and away from said upper and lower driver plate areas when said angular acceleration sensor is tilted with respect to the axis of the pair of torsion bars.

8. An angular acceleration sensor as in claim 7, further comprising left and right housing shells positioned outside said left and right spacers, respectively, for sealing said angular acceleration sensor.

9. An angular acceleration sensor as in claim 7, wherein said left and right spacers and said left and right driver plates are fabricated of materials chosen to electrically insulate said central sensing plate from said left and right driver plates.

10. An angular acceleration sensor as in claim 9, wherein:

said central sensing plate comprises beryllium copper;

said left and right driver plates comprise brass; and

said left and right spacers comprise an electrical insulator.

11. An angular acceleration sensor as in claim 8, wherein said left and right housing shells comprise a molded plastic material.