Double-axle, shock-resistant rotation rate sensor with linear and rotary seismic elements

• US 9,074,890 B2
• Filed: 09/09/2010
• Issued: 07/07/2015
• Est. Priority Date: 09/09/2009
• Status: Active Grant

• Current Assignee: Continental Teves AG & Co. OHG (Continental AG)
• Original Assignee: Continental Teves AG & Co. OHG (Continental AG)
• Inventors: Gnthner, Stefan, Schmid, Bernhard
• Primary Examiner(s): KWOK, HELEN C
• Application Number:
  US13/390,776
• Publication Number:
  US 20120210788A1
• Time in Patent Office: 1,762 Days
• Field of Search: 735/011.2, 735/041.4, 735/040.2, 735/040.4
• US Class Current: 1/1
• CPC Class Codes: G01C 19/5642 using vibrating bars or beams
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis
• CPC Class Codes: G01C 19/574 the devices having two sensing masses in anti-phase motion

Abstract

A micromechanical rotation rate sensor has at least one first and one second seismic mass coupled to at least one first drive device and are suspended such that the first and second seismic masses are driven such that they are deflected in antiphase in one drive mode, with the rotation rate sensor being designed such that it can detect rotation rates about at least two mutually essentially orthogonal sensitive axes, wherein at least the first and second seismic masses are designed and suspended such that they oscillate in antiphase in a first read mode when a first rotation rate about the first sensitive axis is detected, and the first and second seismic masses and/or additional seismic masses are designed and suspended such that they oscillate in antiphase in a second read mode when a second rotation rate about the second sensitive axis is detected.

Claims

1. A micromechanical rotation rate sensor, comprising a substrate whose base surface is aligned parallel to the x-y plane of a Cartesian coordinate system (x, y, z), with the rotation rate sensor having at least one first and one second seismic mass which are coupled to at least one first drive device and are suspended such that the first and the second seismic masses are deflected in antiphase in one drive mode, with the rotation rate sensor being designed to detect rotation rates about at least two mutually essentially orthogonal sensitive axes (z, y), wherein

at least the first and the second seismic masses oscillate in antiphase in a first read mode when a first rotation rate about the first sensitive axis (y) is detected, the first and second seismic masses and/or additional seismic masses oscillate in antiphase in a second read mode when a second rotation rate about the second sensitive axis (z) is detected, and the first and the second seismic masses oscillate in antiphase in a rotational drive mode,

wherein the seismic masses are each associated with a phase read device and an anti-phase read device which are designed and arranged with respect to respective seismic masses to detect the deflections of the respective seismic masses with respect to the first and with respect to the second read mode in each case in phase and in antiphase.

2. The rotation rate sensor as claimed in claim 1, wherein the first and second seismic masses are coupled by at least one coupling spring, the coupling spring allowing deflection of the seismic masses only in antiphase, and in-phase, rotational deflection is suppressed, with the first and second seismic masses additionally being suspended on in each case at least one anchor such that linear deflections of the seismic masses in any direction (x, y, z) are essentially suppressed.

3. The rotation rate sensor as claimed in claim 1, wherein the rotation rate sensor has a single drive device which drives all the seismic masses of the rotation rate sensor, for which purpose the seismic masses are appropriately suspended and are directly or indirectly coupled to the single drive device.

4. The rotation rate sensor as claimed in claim 1, wherein the rotation rate sensor is designed and all of the seismic masses are arranged such that the center of gravity of the entire rotation rate sensor remains essentially at rest with respect to the deflections of the seismic masses in said one drive mode.

5. The rotation rate sensor as claimed in claim 1, wherein the rotation rate sensor is designed such that the first sensitive axis (y) lies on the x-y plane, and the second sensitive axis (z) is parallel to the z axis, that is to say at right angles to the base surface of the substrate.

6. The rotation rate sensor as claimed in claim 5, wherein the x-y plane is in the base surface of the substrate, and the first sensitive axis is parallel to the x axis or to the y axis.

7. The rotation rate sensor as claimed in claim 1, wherein all the seismic masses of the rotation rate sensor can move exclusively for their respective deflections within said one drive mode, for their respective deflections within the first read mode, with this relating only to the seismic masses which oscillate in the first read mode when a rotation rate about the first sensitive axis (y) is detected, and for their respective deflections within the second read mode, with this relating only to the seismic masses which oscillate in the second read mode when a rotation rate about the second sensitive axis (z) is detected, and the deflections take place in antiphase for the seismic masses which oscillate in the respective mode, with the seismic masses being suspended stiffly with respect to all other deflections.

8. The rotation rate sensor as claimed in claim 1, wherein the rotational drive mode is a rotational drive mode about the z axis.

9. The rotation rate sensor as claimed in claim 1, wherein the rotation rate sensor has four additional seismic masses, which are arranged and suspended symmetrically in a rest position with respect to the center of gravity of the entire rotation rate sensor.

10. The rotation rate sensor as claimed in claim 9, wherein the first and second seismic masses can exclusively carry out antiphase, rotational deflections about the z axis and about the x axis, and the additional seismic masses can exclusively carry out linear deflections in the direction of the x axis and in the direction of the y axis.

11. The rotation rate sensor as claimed in claim 9, wherein each of the additional seismic masses is at least partially suspended on a respectively associated frame, in each case in an inner area of the frame, which is in each case coupled to the first or to the second seismic mass, by which drive energy for the drive mode is transmitted from the first and the second seismic masses via a respectively coupling spring elements to the frames and to the additional seismic masses which are at least partially suspended thereon.

12. The rotation rate sensor as claimed in claim 11, wherein the frames can exclusively carry out linear deflections in the direction of the x axis.

13. The rotation rate sensor as claimed in claim 9, wherein one pair of the additional seismic masses is in each case coupled by a coupling beam such that one pair of the additional seismic masses can carry out only antiphase deflections with respect to the second read mode.

15. The use of a rotation rate sensor as claimed in claim 1 in motor vehicles, for detection of a yaw rate, and for detection of a roll rate or a pitch rate of the vehicle.

14. A micromechanical rotation rate sensor, comprising a substrate whose base surface is aligned parallel to the x-y plane of a Cartesian coordinate system (x, y, z), with the rotation rate sensor having at least one first and one second seismic mass which are coupled to at least one first drive device and are suspended such that the first and the second seismic masses are deflected in antiphase in one drive mode, with the rotation rate sensor being designed to detect rotation rates about at least two mutually essentially orthogonal sensitive axes (z, y), wherein

at least the first and the second seismic masses oscillate in antiphase in a first read mode when a first rotation rate about the first sensitive axis (y) is detected, and the first and second seismic masses and/or additional seismic masses oscillate in antiphase in a second read mode when a second rotation rate about the second sensitive axis (z) is detected,

wherein the seismic masses are each associated with a phase read device and an anti-phase read device which are designed and arranged with respect to respective seismic masses to detect the deflections of the respective seismic masses with respect to the first and with respect to the second read mode in each case in phase and in antiphase,

wherein the deflection of any of the seismic masses which oscillate in one of the read modes is detected in a duplicated and differential manner, with in each case two opposing deflections being detected with respect to the antiphase deflection for phase and for antiphase, and wherein the seismic masses which oscillate in one of the read modes are associated overall with at least four read devices.

16. A micromechanical rotation rate sensor, comprising a substrate whose base surface is aligned parallel to the x-y plane of a Cartesian coordinate system (x, y, z), with the rotation rate sensor having at least one first and one second seismic mass which are coupled to at least one first drive device and are suspended such that the first and the second seismic masses are deflected in antiphase in one drive mode, with the rotation rate sensor being designed to detect rotation rates about at least two mutually essentially orthogonal sensitive axes (z, y),

wherein at least the first and the second seismic masses oscillate in antiphase in a first read mode when a first rotation rate about the first sensitive axis (y) is detected, and the first and second seismic masses and/or additional seismic masses oscillate in antiphase in a second read mode when a second rotation rate about the second sensitive axis (z) is detected,

wherein the seismic masses are each associated with read devices which are designed and arranged with respect to the seismic masses such that the read devices detect the deflections of the seismic masses with respect to the first and with respect to the second read mode in each case in phase and in antiphase, and

wherein the first and the second seismic masses oscillate in antiphase in a rotational drive mode.