Inclinometer

• US 6,505,409 B2
• Filed: 11/30/1999
• Issued: 01/14/2003
• Est. Priority Date: 05/31/1999
• Status: Expired due to Fees

• Current Assignee: Ball Semiconductor, Inc.
• Original Assignee: Ball Semiconductor, Inc.
• Inventors: Toda, Risaku, Esashi, Masayoshi
• Primary Examiner(s): Gutierrez; Diego
• Assistant Examiner(s): Jagan; Mirellys
• Application Number:
  US09/449,882
• Publication Number:
  US 20020073563A1
• Time in Patent Office: 1,141 Days
• Field of Search: 33/365,366.11,366.12,366.23,366.24,366.25,366.26,366.27,391,396,398,DIG. 3 340/440,429,689 200/61.45 R,61.52,61.46 73/514.36
• US Class Current: 33/366.24
• CPC Class Codes: G01C 2009/068 resistive
• CPC Class Codes: G01C 9/10 by using rolling bodies , e.g. spheres, cylinders, mercury droplets

Abstract

An inclinometer comprising a spherical mass, a spherical shell having a reference axis and surrounding said spherical mass and a plurality of electrodes mounted on the spherical inner surface of said spherical shell, said inclinometer applied to detect the inclination angle of said reference axis by the output signal of said electrodes.

Claims

1. An electronic device comprising:

a spherical element;

a spherical shell surrounding said spherical element; and

at least three electrodes proximate to the inner surface of the spherical shell, wherein one electrode is positioned to enable a three dimensional position of the spherical element relative to the shell to be calculated by measuring a first capacitance between the one electrode and the spherical element and a second capacitance between any other electrode and the spherical element;

wherein a surface area of the one electrode covers a majority of the remaining surface not covered by the other electrodes.

2. The electronic device of claim 1 wherein a surface area of the one electrode is evenly distributed around the shell.

3. An electronic device comprising:

a spherical element;

a spherical shell surrounding said spherical element; and

at least three electrodes proximate to the inner surface of the spherical shell,

wherein a surface area of one electrode surrounds the other electrodes.

4. The electronic device of claim 3 wherein the surface area of the at least one electrode covers a majority of the remaining surface not covered by the other electrodes.

5. The electronic device of claim 3 further comprising a measuring means operable to calculate a three dimensional position of the spherical element using at least a first electrostatic capacity between the spherical element and the one electrode, and a second electrostatic capacity between the spherical element and at least one of the other electrodes.

6. An electronic device comprising:

a spherical element;

a spherical shell surrounding said spherical element; and

at least three electrodes proximate to the inner surface of the spherical shell,

wherein a surface area of one electrode covers a majority of the remaining surface not covered by the other electrodes.

7. The electronic device of claim 6 wherein the surface area of the one electrode is substantially evenly distributed around the shell.

8. The electronic device of claim 7 wherein the one electrode is a shield electrode.

9. An inclinometer comprising

a spherical mass;

a spherical shell surrounding said spherical mass and having a reference axis; and

a plurality of electrodes mounted on the spherical inner surface of said spherical shell, the plurality of electrodes including at least two detection electrodes and a shield electrode, wherein a surface area of the shield electrode is evenly distributed around the shell so as to substantially surround the detection electrodes;

said inclinometer applied to detect the inclination angle of said reference axis by the output signals of said electrodes, wherein said inclination angle of said reference axis is calculated by using a first electrostatic capacity between said spherical mass and said shield electrode, and a second electrostatic capacity between said spherical mass and at least one of said detection electrodes.

10. The inclinometer of claim 9 wherein the shield electrode occupies a majority of the inner surface of the spherical shell that is not occupied by the detection electrodes.

11. The inclinometer of claim 9 wherein the position of the spherical mass can be calculated in three dimensions.

12. The inclinometer of claim 9 wherein the spherical mass is less than several millimeters in diameter.

13. The inclinometer of claim 12 wherein the spherical mass is approximately one millimeter in diameter.

14. An electronic device comprising:

a spherical element;

a spherical shell surrounding said spherical element; and

at least three electrodes proximate to the inner surface of the spherical shell,

wherein at least one of the three electrodes has a surface area that is evenly distributed around the shell.

15. The electronic device of claim 14 wherein the surface area of the at least one electrode substantially surrounds the other electrodes.

16. The electronic device of claim 14 wherein the electronic device is an inclinometer.

17. The electronic device of claim 14 further comprising a gap defined by an outer surface of the spherical element and the inner surface of the shell, wherein the gap is at most several microns wide.

18. The electronic device of claim 17 wherein the gap is at least partially filled with a fluid.

19. The electronic device of claim 17 wherein the spherical element is less than