Yaw-rate sensor and method for operating a yaw-rate sensor

• US 8,844,357 B2
• Filed: 11/11/2011
• Issued: 09/30/2014
• Est. Priority Date: 11/23/2010
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Scheben, Rolf, Kuhlmann, Burkhard, Balslink, Thorsten, Meisel, Daniel Christoph, Schmidt, Benjamin
• Primary Examiner(s): KWOK, HELEN C
• Application Number:
  US13/294,752
• Publication Number:
  US 20120125099A1
• Time in Patent Office: 1,054 Days
• Field of Search: 735/041.2, 735/041.4, 735/040.2, 735/040.4
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/5747 each sensing mass being connected to a driving mass, e.g. driving frames

Abstract

A yaw-rate sensor includes: a substrate having a main extension plane for detecting a yaw rate about a first axis extending parallel to the main extension plane; a first Coriolis element; a second Coriolis element; a third Coriolis element; and a fourth Coriolis element. The first Coriolis element and the fourth Coriolis element are drivable in the same direction parallel to a second axis extending parallel to the main extension plane and perpendicularly to the first axis. The first Coriolis element and the second Coriolis element are drivable in opposite directions parallel to the second axis. The first Coriolis element and the third Coriolis element are drivable in opposite directions parallel to the second axis.

Claims

1. A yaw-rate sensor, comprising:

a substrate having a main plane of extension for detecting a yaw rate about a first axis extending parallel to the main plane of extension; and

a first Coriolis element, a second Coriolis element, a third Coriolis element, and a fourth Coriolis element;

a transformation unit coupled to a drive unit; and

a corner spring connecting the transformation unit to the substrate

wherein;

the first Coriolis element and the fourth Coriolis element are configured to be driven in the same direction parallel to a second axis extending parallel to the main plane of extension and perpendicularly to the first axis;

the first Coriolis element and the second Coriolis element are configured to be driven in opposite directions parallel to the second axis; and

the first Coriolis element and the third Coriolis element are configured

to be driven in opposite directions parallel to the second axis; and

wherein the first, second, third, and fourth Coriolis elements are coupled to the transformation unit.

2. The yaw-rate sensor as recited in claim 1, wherein the third Coriolis element and the fourth Coriolis element are connected to each other via a coupling element, and wherein the coupling element is connected to the substrate.

3. The yaw-rate sensor as recited in claim 2, wherein the coupling element has an axis of rotation parallel to the main plane of extension, and wherein the axis of rotation extends parallel to one of the first axis or the second axis.

4. The yaw-rate sensor as recited in claim 2, wherein the coupling element has a rocker structure having a symmetric mass distribution with respect to the axis of rotation.

5. The yaw-rate sensor as recited in claim 2, wherein the coupling element is coupled to the substrate, and wherein the coupling element includes a bar which is soft with respect to torsion and rigid with respect to double bending.

6. The yaw-rate sensor as recited in claim 1, wherein the transformation unit has a quadrangular design and includes angular transformation sub-elements.

12. The yaw-rate sensor as recited in claim 6, wherein the quadrangular transformation unit has an L-shaped sub-element and is connected to the substrate at a corner of the L-shaped sub-element via the corner spring.

7. A method for operating a yaw-rate sensor including a first Coriolis element, a second Coriolis element, a third Coriolis element, a fourth Coriolis element, and a substrate having a main plane of extension for detecting a yaw rate about a first axis extending parallel to the main plane of extension, the method comprising:

driving the first Coriolis element and the fourth Coriolis element in the same direction parallel to a second axis extending parallel to the main plane of extension and perpendicularly to the first axis;

driving the first Coriolis element and the second Coriolis element in opposite directions parallel to the second axis; and

driving the first Coriolis element and the third Coriolis element in opposite directions parallel to the second axis;

wherein a transformation unit is coupled to a drive unit and a corner spring connects the transformation unit to the substrate; and

wherein the first, second, third, and fourth Coriolis elements are coupled to the transformation unit.

8. The method as recited in claim 7, wherein the first through fourth Coriolis elements are deflected parallel to a third axis which is perpendicular to the first axis and the second axis, and wherein first through fourth detection signals are generated by the deflection of the first through fourth Coriolis elements, respectively, and wherein the first through fourth detection signals are evaluated.

9. The method as recited in claim 8, wherein the first detection signal and the fourth detection signal are added to form a first sum signal, and wherein the second detection signal and the third detection signal are added to form a second sum signal.

10. The method as recited in claim 9, wherein a difference signal is formed from the first sum signal and the second sum signal, and wherein the yaw rate is determined as a function of the difference signal.

11. The method as recited in claim 10, wherein the determined yaw rate is a yaw rate about at least one of the first axis and the third axis.