Angular speed measuring device

• US 5,385,047 A
• Filed: 06/11/1993
• Issued: 01/31/1995
• Est. Priority Date: 07/16/1992
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Cochard, Roland, Jeannin, Pierre
• Primary Examiner(s): Williams, Hezron E.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US08/075,768
• Time in Patent Office: 599 Days
• Field of Search: 73/517 A, 73/517 R, 73/517 AV, 73/505, 73/510, 73/511
• US Class Current: 73/504.02
• CPC Class Codes: G01C 19/00 Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 2015/0828 the mass being of the paddle type being suspended at one of its longitudinal ends
• CPC Class Codes: G01P 21/00 Testing or calibrating of apparatus or devices covered by the preceding groups

Abstract

The angular speed measuring device has two acceleration sensors mounted on a circular plate rotating about a first rotation axis and each sensor generates a signal depending on a Coriolis force produced when it rotates about two additional rotation axes. The rotation axes are orthogonal and the acceleration sensors are at least partially made of silicon and displaced by 180° on the planar plate. An initial signal processing device is mounted directly on a circular planar plate on which the acceleration sensors are mounted. A light emitting diode is used to transmit the signals from the initial signal processing circuit to a signal processing circuit off the planar plate via a photodiode receiving device.

Claims

1. Angular speed measuring device comprising

a rigid planar plate rotatable about a first rotation axis;

at least one acceleration sensor mounted on said rigid planar plate so as to be movable on a circular path about said first rotation axis by rotation of said planar plate, said at least one acceleration sensor being at least partially made of silicon and including means for generating a signal depending on a Coriolis force experienced by said at least one acceleration sensor is sensor when said at least one acceleration sensor is rotated about two other rotation axes, said two other rotation axes and said first rotation axis being orthogonal to each other;

transmitting means for transmitting said signal off of said planar plate in a contactless manner, said transmitting means being mounted on said planar plate and connected to said at least one acceleration sensor for contactless transmission of said signal generated in said at least one acceleration sensor from said planar plate;

receiver means for receiving said signal transmitted from said transmitting means, said receiver means being located off said planar plate; and

means for processing said signal received by said receiver means to obtain said angular speed, said means for processing said signal received by said receiver means being connected to said receiver means and being located off said planar plate.

2. Angular speed measuring device as defined in claim 1, further comprising initial signal processing means for initial processing of said signal generated by said at least one acceleration sensor, said initial signal processing means being fixed on said planar plate and connected to said at least one acceleration sensor to receive said signal from said at least one acceleration sensor and connected to said transmitting means to transmit said signal to said receiver means.

3. Angular speed measuring device as defined in claim 1, wherein said planar plate is made of a member selected from the group consisting of glass, silicon and ceramic materials.

4. Angular speed measuring device as defined in claim 1, wherein said transmitting means comprises a light emitting diode and said receiver means comprises a photodiode.

5. Angular speed measuring device as defined in claim 1, wherein said transmitting means and said receiver means are coils.

6. Angular speed measuring device as defined in claim 2, further comprising means for supplying power to said initial signal processing means including a rotating transformer.

7. Angular speed measuring device as defined in claim 6, wherein said rotating transformer includes a rotating coil formed as one of a thickfilm coil and a thinfilm coil on an underside of the planar plate.

8. Angular speed measuring device comprising:

a rigid planar plate rotatable about a first rotation axis;

means for rotating said planar plate in at least one rotation direction at constant rotation speed about said first rotation axis connected to said planar plate;

two acceleration sensors fixed on said planar plate and located 180°

degrees from each other on said planar plate so as to be movable on a circular path about said first rotation axis by rotation of said planar plate, each of said acceleration sensors being at least partially made of silicon and including means for generating a signal from each of said acceleration sensors depending on a Coriolis force experienced by said acceleration sensors when said acceleration sensors are rotated about two other rotation axes, said two other rotation axes and said first rotation axis being in an orthogonal relationship to each other;

transmitting means for transmitting said signal of both of said acceleration sensors off said planar plate, said transmitting means being mounted on said planar plate and connected to both of said acceleration sensors for contactless transmission of said signal generated in said acceleration sensors off said planar plate;

receiver means for receiving said signal transmitted from said transmitting means, said receiver means being located off said planar plate; and

means for processing said signal received by said receiver means to obtain said angular speed, said means for processing said signal received by said receiver means being connected to said receiver means and being located off said planar plate.

9. Angular speed measuring device as defined in claim 8, wherein said means for processing said signal received by said receiver means to obtain said angular speed includes a difference forming means for forming a signal difference by subtraction of said signal produced by one of said acceleration sensors from said signal produced by another of said acceleration sensors.

10. Angular speed measuring device as defined in claim 9, wherein said means for processing said signal received by said receiver means to obtain said angular speed includes phase dependent filter means for separating two signal components dependent on said angular speed from said signal difference, said phase dependent filter means being connected to said difference forming means to receive said signal difference and including synchronous modulation means for producing said two signal components.

11. Angular speed measuring device as defined in claim 10, wherein said means for processing said signal received by said receiver means includes computer means for determining said angular speed from said two signal components, said computer means being connected to said synchronous modulation means to receive said two signal components from said synchronous modulation means and to determine a projection of said angular speed on respective ones of said other two rotation axes from said two signal components.

12. Angular speed measuring device as defined in claim 11, wherein said transmitting means comprises a light emitting diode and said receiving means comprises a photodiode.

13. Angular speed measuring device as defined in claim 11, wherein said transmitting means and said receiving means are coils.