Capacitive sensor and actuator

• US 20110050251A1
• Filed: 07/29/2010
• Published: 03/03/2011
• Est. Priority Date: 08/27/2009
• Status: Abandoned Application

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Keck, Marian, Buhmann, Alexander, FRANKE, Axel
• Application Number:
  US12/846,314
• Publication Number:
  US 20110050251A1
• Time in Patent Office: Days
• US Class Current: 324/658
• CPC Class Codes: B81B 2201/0221 Variable capacitors
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2201/033 Comb drives
• CPC Class Codes: B81B 3/0094 Constitution or structural means for improving or controlling physical properties not provided for in B81B3/0067 - B81B3/0091
• CPC Class Codes: G01D 5/2412 by varying overlap
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: H02N 1/008 Laterally driven motors, e.g. of the comb-drive type

Abstract

A capacitive sensor and a capacitive actuator having at least one seismic mass deflectably mounted on a substrate. A comb electrode having comb fingers is mounted on the seismic mass, and a comb electrode having comb fingers is mounted on the substrate in such a way that the comb fingers are situated parallel to a deflection direction of the seismic mass and interlock in a comb-like manner. The characteristic curve of the sensor or actuator is adjusted by optimizing the geometry of at least one comb electrode, in particular of at least one comb finger.

Claims

1. A capacitive sensor comprising:

a substrate;

at least one seismic mass deflectably mounted on the substrate;

a first comb electrode having first comb fingers mounted on the seismic mass; and

a second comb electrode having second comb fingers mounted on the substrate,

wherein the first and second comb fingers are situated parallel to a deflection direction of the seismic mass and interlock in a comb-like manner, and

wherein a characteristic curve of the sensor is adjusted by optimizing a geometry of at least one of the first and second comb electrodes.

2. The capacitive sensor according to claim 1, wherein the characteristic curve of the sensor is adjusted by optimizing a geometry of at least one of the first and second comb fingers.

3. The capacitive sensor according to claim 1, wherein the geometry of the at least one of the first and second comb electrodes is optimized via a predetermined height profile of at least one of the first and second comb fingers.

4. The capacitive sensor according to claim 3, wherein the height profile is produced by applying insulation.

5. The capacitive sensor according to claim 1, wherein the geometry of the at least one of the first and second comb electrodes is optimized via a predetermined length profile of at least one of the first and second comb fingers.

6. The capacitive sensor according to claim 1, wherein the geometry of the at least one of the first and second comb electrodes is optimized via a predetermined distance profile of at least one of the first and second comb fingers.

7. A capacitive actuator comprising:

a substrate;

at least one seismic mass deflectably mounted on the substrate;

a first comb electrode having first comb fingers mounted on the seismic mass; and

a second comb electrode having second comb fingers mounted on the substrate,

wherein the first and second comb fingers are situated parallel to a deflection direction of the seismic mass and interlock in a comb-like manner, and

wherein a characteristic curve of the actuator is adjusted by optimizing a geometry of at least one of the first and second comb electrodes.

8. The capacitive actuator according to claim 7, wherein the characteristic curve of the actuator is adjusted by optimizing a geometry of at least one of the first and second comb fingers.

9. The capacitive actuator according to claim 7, wherein the geometry of the at least one of the first and second comb electrodes is optimized via a predetermined height profile of at least one of the first and second comb fingers.

10. The capacitive actuator according to claim 9, wherein the height profile is produced by applying insulation.

11. The capacitive actuator according to claim 7, wherein the geometry of the at least one of the first and second comb electrodes is optimized via a predetermined length profile of at least one of the first and second comb fingers.

12. The capacitive actuator according to claim 7, wherein the geometry of the at least one of the first and second comb electrodes is optimized via a predetermined distance profile of at least one of the first and second comb fingers.