Micromechanical rate of rotation sensor having ring with drive element and detection element

• US 5,889,207 A
• Filed: 04/15/1997
• Issued: 03/30/1999
• Est. Priority Date: 05/03/1996
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Lutz, Markus
• Primary Examiner(s): Oda, Christine K.
• Application Number:
  US08/839,660
• Time in Patent Office: 714 Days
• Field of Search: 73/504.13, 73/504.12, 73/504.02, 73/1.38, 73/1.86, 73/504.01, 73/504.18, 361/292
• US Class Current: 73/504.13
• CPC Class Codes: G01C 19/5684 the devices involving a micromechanical structure

Abstract

A rate of rotation sensor is structured as a micromechanical component on the surface of a substrate. The rate of rotation sensor has a ring with drive elements and detection elements. The ring is made to oscillate by means of the drive elements, and the deformation of the ring which results from Coriolis forces is detected by the detection elements.

Claims

1. A micromechanical rate of rotation sensor, comprising:

a substrate having a surface;

a ring including oscillation springs;

an arrangement exciting oscillations in the ring, the oscillations having oscillation bulges and oscillation nodes;

at least one detection element arranged in the oscillation nodes for detecting a shift in the oscillation nodes caused by a rotation; and

a bearing block fixed to the substrate,

wherein the oscillation springs are suspended on the bearing block,

wherein the ring, the arrangement and the at least one detection element are formed as micromechanical elements on the surface of the substrate and have a same height above the surface of the substrate, and

wherein the arrangement includes a plurality of movable electrodes and a plurality of fixed electrodes arranged opposite and parallel to one another, the movable electrodes are connected to the ring, the fixed electrodes are connected to the substrate, and an oscillating voltage is applied between the fixed electrodes and the movable electrodes to pull the movable electrodes toward the fixed electrodes.

2. The sensor according to claim 1, wherein the bearing block connects the fixed electrodes to the substrate.

3. The sensor according to claim 1,

wherein the oscillation springs suspend the ring on the bearing block.

4. The sensor according to claim 1, wherein the substrate includes silicon, and further comprising an insulating layer coupling the bearing block to the substrate.

5. The sensor according to claim 1, wherein the ring, the arrangement and the at least one detection element include monocrystalline silicon.

6. The sensor according to claim 1, wherein the ring, the arrangement and the at least one detection element include polycrystalline silicon.

7. The sensor according to claim 1, wherein the substrate includes an insulating material, and wherein the ring, the arrangement and the at least one detection element include a metal.

8. A micromechanical rate of rotation sensor, comprising:

a substrate having a surface;

a ring including oscillation springs;

an arrangement exciting oscillations in the ring, the oscillations having oscillation bulges and oscillation nodes;

at least one detection element arranged in the oscillation nodes for detecting a shift in the oscillation nodes caused by a rotation; and

a bearing block fixed to the substrate,

wherein the oscillation springs are suspended on the bearing block,

wherein the ring, the arrangement and the at least one detection element are formed as micromechanical elements on the surface of the substrate and have a same height above the surface of the substrate,

wherein the at least one detection element includes a plurality of detection elements, the detection elements include a plurality of movable electrodes and a plurality of fixed electrodes arranged opposite to one another, the movable electrodes are connected to the ring, the fixed electrodes are connected to the substrate, and a capacitive signal is measured between the fixed electrodes and the movable electrodes, and

wherein the fixed electrodes are arranged parallel to each other, and the movable electrodes are arranged parallel to each other.

9. The sensor according to claim 8, wherein the bearing block connects the fixed electrodes to the substrate.