Rotational rate sensor with two acceleration sensors

• US 5,703,293 A
• Filed: 05/13/1996
• Issued: 12/30/1997
• Est. Priority Date: 05/27/1995
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Lutz, Markus, Wolf, Joerg, Zabler, Erich
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Kwok, Helen C.
• Application Number:
  US08/645,375
• Time in Patent Office: 596 Days
• Field of Search: 73/504.02, 73/504.03, 73/570, 73/571, 73/572, 73/574.32, 73/504.12
• US Class Current: 73/504.02
• CPC Class Codes: G01C 19/574 the devices having two sensing masses in anti-phase motion

Abstract

A rotational sensor has a vibrating weight with two acceleration sensors mounted on it. The two acceleration sensors are designed to detect forces acting at a right angle to each other. The vibrating weight is set in vibration by means of driving devices, and rotation of the rotational sensor about two axes of rotation that are normal to each other is detected with the help of the acceleration sensors. The Coriolis forces in a plane are determined in this way.

Claims

1. A rotational rate sensor comprising:

at least one vibrating weight;

an excitation device for inducing vibration of the vibrating weight;

a first deflectable weight arranged on the vibrating weight;

a first analyzer device for determining a deflection of the first deflectable weight;

a second deflectable weight arranged on the vibrating weight; and

a second analyzer device for determining a deflection of the second deflectable weight;

wherein directions of deflection of the first and second deflectable weights are not parallel to each other and are not parallel to a direction of vibration of the vibrating weight.

2. The sensor according to claim 1, wherein the sensor is at least partially composed of silicon.

3. The sensor according to claim 1, wherein the sensor is arranged on a common substrate with an additional rotational rate sensor, and the sensor vibrates in phase opposition with the additional rotational rate sensor.

4. The sensor according to claim 1, wherein the first and second deflectable weights have suspensions, the suspensions having a rigidity, with respect to deflection in the direction of vibration of the vibrating weight, greater than a threshold value.

5. The sensor according to claim 1, wherein the first deflectable weight is arranged as a silicon wafer deflectable at a right angle to the direction of vibration of the vibrating weight.

6. The sensor according to claim 1, wherein the second deflectable weight has a first comb structure deflectable relatively toward a second comb structure.

7. The sensor according to claim 1, wherein the sensor is arranged on a common substrate with at least one additional rotational rate sensor, a rotation of the substrate about three axes of rotation normal to each other being determined by a measured Coriolis force.