Micromechanical rotation rate sensor

• US 6,776,041 B1
• Filed: 08/15/2002
• Issued: 08/17/2004
• Est. Priority Date: 09/24/1999
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Hauer, Joerg, Funk, Karsten, Fehrenbach, Michael
• Primary Examiner(s): Kwok, Helen C.
• Application Number:
  US10/089,018
• Time in Patent Office: 733 Days
• Field of Search: 735/041.8, 735/041.3, 735/040.8, 735/040.4, 735/040.2, 735/040.9, 735/041.1, 735/041.2
• US Class Current: 73/504.09
• CPC Class Codes: G01C 19/5712 the devices involving a micromechanical structure

Abstract

A micromechanical yaw rate sensor having: a substrate having an anchoring device provided on the substrate; and an annular flywheel that is connected, via a flexural spring system, with the anchoring device in such a way that the area of connection with the anchoring device is located essentially in the center of the ring, so that the annular flywheel is able to be displaced, elastically from its rest position, about an axis of rotation situated perpendicular to the substrate surface, and about at least one axis of rotation situated parallel to the substrate surface. The anchoring device has two bases that are situated opposite one another and are connected fixedly with the substrate, connected with one another via a bridge. A V-shaped flexural spring of the flexural spring system is attached to each of the opposite sides of the bridge in such a way that the apex is situated on the bridge and the limbs are spread towards the flywheel with an opening angle.

Claims

1. A micromechanical yaw rate sensor, comprising:

a substrate;

a bridge;

an anchoring device provided on the substrate and including two opposite bases that are connected fixedly with the substrate and that are connected with one another via the bridge;

a flexural spring device; and

an annular flywheel that is connected via the flexural spring device with the anchoring device such that an area of connection with the anchoring device is located essentially in a center of a ring of the flexural spring device, so that the annular flywheel is displaceable, elastically from a rest position, about an axis of rotation situated perpendicular to a surface of the substrate, and about at least one axis of rotation situated parallel to the surface of the substrate, wherein;

at least one V-shaped flexural spring of the flexural spring device is attached to each of opposite sides of the bridge in such a way that an apex is situated on the bridge and limbs of the V-shaped flexural spring are spread towards the annular flywheel with an opening angle other than 90 degrees.

2. The micromechanical yaw rate sensor according to claim 1, wherein:

the at least one V-shaped flexural spring includes a first V-shaped flexural spring and a second V-shaped flexural spring, and

the opening angle is equal for the first V-shaped flexural spring and the second V-shaped flexural spring.

3. The micromechanical yaw rate sensor according to claim 2, wherein:

the first V-shaped flexural spring and the second V-shaped flexural spring are attached to the bridge such that the first V-shaped flexural spring and the second V-shaped flexural spring form an X shape.

4. The micromechanical yaw rate sensor according to claim 3, wherein:

the opening angle is selected such that a natural frequency about the axis of rotation situated perpendicular to the surface of the substrate is smaller than each natural frequency about the axis of rotation situated parallel to the surface of the substrate.

5. The micromechanical yaw rate sensor according to claim 1, wherein:

the two opposite bases are in the shape of a wedge and include two wedge tips, and

the bridge connects the two wedge tips with one another.

6. The micromechanical yaw rate sensor according to claim 1, wherein:

the bridge is suspended freely over the substrate from the two opposite bases.

7. The micromechanical yaw rate sensor according to claim 1, wherein:

the micromechanical yaw rate sensor can be manufactured using one of silicon surface micromechanical technology and another micromechanical technology.

8. A micromechanical yaw rate sensor, comprising:

a substrate;

a bridge;

an anchoring device provided on the substrate and including two opposite bases that are connected fixedly with the substrate and that are connected with one another via the bridge;

a flexural spring device; and

an annular flywheel that is connected via the flexural spring device with the anchoring device such that an area of connection with the anchoring device is located essentially in a center of a ring of the flexural spring device, so that the annular flywheel is displaceable, elastically from a rest position, about an axis of rotation situated perpendicular to a surface of the substrate, and about at least one axis of rotation situated parallel to the surface of the substrate;

wherein at least one V-shaped flexural spring of the flexural spring device is attached to each of the opposite sides of the bridge in such a way that an apex is situated on the bridge and limbs of the V-shaped flexural spring are spread towards the annular flywheel with an opening angle; and

wherein the opening angle is selected such that a natural frequency about the axis of rotation situated perpendicular to the surface of the substrate is smaller than each natural frequency about the axis of rotation situated parallel to the surface of the substrate.