Mechanical component, mechanical system, and method for operating a mechanical component

Patent metadata

Field	Value
Publication number	US-9593013-B2
Application number	US-201314060887-A
Country	US
Kind code	B2
Filing date	Oct 23, 2013
Priority date	Oct 26, 2012
Publication date	Mar 14, 2017
Grant date	Mar 14, 2017

Abstract

A mechanical component has: a mount; an adjustable part selectively set at least into a first vibration mode having a first natural frequency and into a second vibration mode having a second natural frequency; a first sensor unit providing a first sensor signal; and a second sensor unit providing a second sensor signal. The first and second sensor units are interconnected in such a way that an overall signal is generated with the aid of at least the first and second sensor signals, the overall signal having an overall ratio of a first maximum absolute value which arises in the event of an excitation of the first vibration mode, and a second maximum absolute value which arises in the event of an excitation of the second vibration mode.

First claim

What is claimed is:

1. A mechanical component, comprising:
a mount;
an adjustable part connected to the mount in such a way that the adjustable part is selectively set in relation to the mount at least into a first vibration mode having a first natural frequency and into a second vibration mode having a second natural frequency different from the first natural frequency;
a first sensor unit providing a first sensor signal having a first ratio of a first maximum absolute value of the first sensor signal which arises in the event of an excitation of the first vibration mode of the adjustable part and a second maximum absolute value of the first sensor signal which arises in the event of an excitation of the second vibration mode of the adjustable part; and
a second sensor unit providing a second sensor signal having a second ratio of a first maximum absolute value of the second sensor signal which arises in the event of an excitation of the first vibration mode of the adjustable part and a second maximum absolute value of the second sensor signal which arises in the event of an excitation of the second vibration mode of the adjustable part;
wherein the first sensor unit and the second sensor unit are interconnected with one another to generate an overall signal with the aid of at least the first and second sensor signals, the overall signal having an overall ratio of a first maximum absolute value of the overall signal which arises in the event of an excitation of the first vibration mode of the adjustable part and a second maximum absolute value of the overall signal which arises in the event of an excitation of the second vibration mode of the adjustable part, and wherein the overall ratio is greater than the first ratio of the first sensor signal and greater than the second ratio of the second sensor signal.

2. The mechanical component as recited in claim 1 , wherein the first maximum absolute value of the overall signal is greater than or equal to a sum of the first maximum absolute value of the first sensor signal and the first maximum absolute value of the second sensor signal, and wherein the second maximum absolute value of the overall signal is less than or equal to a difference between the second maximum absolute value of the first sensor signal and the second maximum absolute value of the second sensor signal.

3. The mechanical component as recited in claim 2 , wherein the mechanical component is a micromechanical component.

4. The mechanical component as recited in claim 2 , wherein the adjustable part is connected to the mount via a first spring and a second spring, and wherein the first and second springs are implemented symmetrically to one another with respect to a plane of symmetry.

5. The mechanical component as recited in claim 4 , wherein (i) the first sensor unit is implemented on at least one of the first spring and a first anchor of the first spring on the mount, and (ii) the second sensor unit is implemented on at least one of the second spring and a second anchor of the second spring on the mount.

6. The mechanical component as recited in claim 4 , wherein the first vibration mode is asymmetrical with respect to the plane of symmetry and the second vibration mode is symmetrical with respect to the plane of symmetry, and wherein the overall signal is generated as a differential voltage based on a first voltage signal provided as the first sensor signal and a second voltage signal provided as the second sensor signal.

7. The mechanical component as recited in claim 4 , wherein the first vibration mode is symmetrical with respect to the plane of symmetry and the second vibration mode is asymmetrical with respect to the plane of symmetry, and wherein the overall signal is generated with the aid of a transducer as a combined voltage signal based on a first voltage signal provided as the first sensor signal and a second voltage signal provided as the second sensor signal.

8. The mechanical component as recited in claims 4 , further comprising:
a drive body suspended on the mount via the first spring and the second spring, wherein the adjustable part is connected to the drive body via at least one intermediate spring.

9. The mechanical component as recited in claim 4 , wherein the first sensor unit is a first full bridge and the second sensor unit is a second full bridge.

10. The mechanical component as recited in claim 4 , wherein the first sensor unit is a first half bridge and the second sensor unit is a homopolar second half bridge.

11. The mechanical component as recited in claim 4 , wherein the first sensor unit is a first half bridge and the second sensor unit is a second half bridge having opposite polarity.

12. A mechanical system, comprising:
a mechanical component which includes:
a mount;
an adjustable part connected to the mount in such a way that the adjustable part is selectively set in relation to the mount at least into a first vibration mode having a first natural frequency and into a second vibration mode having a second natural frequency different from the first natural frequency;
a first sensor unit providing a first sensor signal having a first ratio of a first maximum absolute value of the first sensor signal which arises in the event of an excitation of the first vibration mode of the adjustable part and a second maximum absolute value of the first sensor signal which arises in the event of an excitation of the second vibration mode of the adjustable part; and
a second sensor unit providing a second sensor signal having a second ratio of a first maximum absolute value of the second sensor signal which arises in the event of an excitation of the first vibration mode of the adjustable part and a second maximum absolute value of the second sensor signal which arises in the event of an excitation of the second vibration mode of the adjustable part;
wherein the first sensor unit and the second sensor unit are interconnected with one another to generate an overall signal with the aid of at least the first and second sensor signals, the overall signal having an overall ratio of a first maximum absolute value of the overall signal which arises in the event of an excitation of the first vibration mode of the adjustable part and a second maximum absolute value of the overall signal which arises in the event of an excitation of the second vibration mode of the adjustable part, and wherein the overall ratio is greater than the first ratio of the first sensor signal and greater than the second ratio of the second sensor signal; and

a regulating device configured to: (i) ascertain a frequency for which the overall signal has an unambiguous maximum, wherein the overall signal is provided as a frequency spectrum; (ii) establish the ascertained frequency as a first natural frequency; and (iii) set the adjustable part into a vibration movement identical to the first vibration mode in consideration of the established first natural frequency.

13. The mechanical system as recited in claim 12 , wherein the regulating device includes a phase-locked loop.

14. A method for operating a mechanical component having a mount, an adjustable part, an actuator unit, a first sensor unit, and a second sensor unit, the method comprising:
setting the adjustable part into vibration movements in relation to the mount with the aid of the actuator unit, a frequency of the vibration movements being varied within a predefined frequency value range which includes a first natural frequency of a first vibration mode of the adjustable part and a second natural frequency of a second vibration mode of the adjustable part;
providing by the first s

Assignees

• Bosch Gmbh Robert

Inventors

• Iyad Al Dibs Mohamad
• Njikam Njimonzie Frederic
• Muchow Joerg

Classifications

• B81C99/003 Primary

  Characterising MEMS devices, e.g. measuring and identifying electrical or mechanical constants · CPC title

• G02B26/0833

  the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD (G02B26/0825 takes precedence; micromechanical devices in general B81B) · CPC title