Title of Invention

METHOD OF OPERATING RATE-OF-ROTATION SENSOR

Abstract The invention discloses a method for operating a sensor (1), particularly, a yaw rate sensor, which is housed inside a housing (10). In order to detect the dangerous influence of mechanical vibrations upon the output measured value of the sensor (1), the vibrations are sensed at the location of the sensor (1), and the sensor (1) or an electronic device (3) interacting with the sensor (1) is switched off so long as the vibrations exceed an established intensity. The method can be used, in particular, in a driving dynamics control (FDR) of a road vehicle.
Full Text

BACKGROUND OF THE INVENTION
Such sensors, especially rate-of-rotation sensors, can be expediently installed in a housing
together with an associated evaluating electronic unit. For this purpose, the sensors can
be mounted together with the other electronics on the same printed-circuit board, or can
be provided with their own printed-circuit board (baby board). Rate-of-rotation sensors
are used, for example, in systems for electronic stability control (ESC), adaptive cruise
control (ACC) and roll stability control (RSC). A rate-of-rotation sensor detects rotation
around the vertical axis of the vehicle. For this purpose, an oscillating element such as a
tuning fork or oscillating body of some other construction is disposed inside the sensor.
This is excited to vibration and it measures a deflection caused by coriolis force during
rotation around a vertical axis. Known rate-of-rotation sensors (International Patent WO
03/067190 A1, German Patent 10215853 A1, German Patent 44973 C3) are usually
manufactured as micromechanical components and are therefore sensitive to shaking and
other mechanical vibrations. Such perturbations can cause false readings and even
destruction of the sensor.
The said false readings are to be regarded as particularly critical for the aforementioned
applications in motor vehicles, since thereby false control signals can be generated and
thus danger to the vehicle and operator can result. The control signals then do not
correspond to the true vehicle behavior. Furthermore, the control system is not always
capable of distinguishing mem from the actual rate of rotation.
As a remedy, German Patent 10022968 Al discloses a special cushioning and damping
design of the printed-circuit board on which the sensor is mounted. However, this means
that the electronics are considerably more expensive. Furthermore, it is technologically
difficult to maintain control over such damping devices, since the cushioning and

damping effects can vary with time as a result of aging.
As has been found in tests, it is particularly vibrations of a certain frequency range,
namely such between 300 and 450 Hz, that are responsible for impaired output signals of
rate-of-rotation sensors.
At and above a certain level of vibration, these may lead to DC offset drift of the output
signal.
Also conceivable, of course, is the use of particularly high-quality rate-of-rotation sensors
that are insensitive to vibrations and impacts. Because of the high price of such sensors,
however, the use thereof as mass-produced components in motor vehicles is impractical.
OBJECTIVE OF THE INVENTION
The object of the invention is to avoid defective output signals of rate-of-rotation sensors
and to prevent any harmful effect of such defective signals on electronic stability control
or other vehicle systems.
Accordingly the present invention provides a method for operating a sensor, especially a
rate-of-rotation sensor, which is installed on a printed-circuit board in a housing,
characterized in that mechanical vibrations at the location of the sensor are measured and
the sensor and/or an electronic unit cooperating with the sensor is/are deactivated for as
long as the vibrations exceed a defined intensity and/or occur within a defined frequency
band.
By means of the inventive method there can be used rate-of-rotation sensors mat are
considerably more cost-effective than heretofore. Consequently there is achieved a
noteworthy reduction in costs of the ESC system. This is possible even when the cost
increase due to the additional acceleration sensors is taken into consideration.
Furthermore, there is no longer any need for complex measures to damp vibrations of the
printed-circuit board, and more cost-effective materials, such as plastic, can be used for

the housing.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The invention will be explained in more detail hereinafter on the basis of a drawing.
The single Fig. 1 shows a schematic diagram of an electronic unit that is installed in a
housing and that contains a rate-of-rotation sensor in addition to other components.
Fig. 1 shows a printed-circuit board (7), to which there are soldered several electronic
components (1, 3, 4, 5, 6). Printed-circuit board (7) is fixed inside an electronics housing
(10) by means of holding members (8, 9). As an example, electronics housing (10) can
contain an electronic stability control (ESC) system and be disposed on board a motor
vehicle.
DETAILED DESCRIPTION
Printed-circuit board (7) is provided with an electronic unit (3), which among other tasks
receives and evaluates the output signals of a sensor (1), especially of a rate-of-rotation
sensor. This component (3) (the electronic unit) is also representative of further
electronic components of the electronic stability control system that are not indicated
individually.
To execute the inventive method, one or more, and in the present case three acceleration
sensors (4, 5, 6) are disposed in the immediate proximity of rate-of-rotation sensor (1).
Advantageously, these acceleration sensors are chosen such that they can measure
different vibrational bandwidths or frequencies and/or have different measuring
directions.
For the purpose of reliably recording all vibrations that occur, there are advantageously
used three acceleration sensors (4, 5, 6) set up for measurement in three different spatial
axes.

Sensor (1) (rate-of-rotation sensor) can also be mounted together with acceleration
sensors (4, 5, 6) on a special printed-circuit board or baby board (not illustrated). This
has the advantage that the rate-of-rotation sensor can be prefabricated together with the
acceleration sensors as a single module.
In an expedient embodiment, housing (10) and/or printed-circuit board (7) can
additionally be constructed such that they are disposed far from critical mechanical sensor
excitations or vibrations. Rate-of-rotation sensor (1) is then advantageously placed at a
position located far from the maximum vibrational amplitudes. Such a suitable position
can be determined by tests, for example.
In another expedient embodiment, holding members (8, 9) for printed-circuit board (7)
can be additionally designed to damp vibrations. By this feature, the harmful vibrations
transmitted to rate-of-rotation sensor (1) are further reduced.
Housing (10) and/or printed-circuit board (7) can also be mechanically designed such that
external vibrational excitation leads to only small, narrowly confined resonance ranges.
Measures in this regard are known to the person skilled in the art. The rate-of-rotation
sensor is then placed at a position where no resonance range occurs. This can be
determined by tests.
The vibrations measured or detected by acceleration sensors (4, 5, 6) in the manner
according to the invention are evaluated in electronic unit (3). Should these vibrations
exceed a defined intensity and occur within a certain, critical frequency band, which in
the present case ranges approximately from 300 to 450 Hz, electronic unit (3) initiates
appropriate actions, such as deactivating downstream functions, to ensure that impaired
output signals cannot be transmitted further and thus lead to erroneous vehicle reactions.
By means of the invention, there is achieved a considerable improvement in the safety
level of ESC or other systems, accompanied at the same time by a cost reduction.

WE CLAIM:
1. A method for operating a sensor (1), especially a rate-of-rotation sensor, which is
installed on a printed-circuit board (7) in a housing (10), characterized in that mechanical
vibrations at the location of the sensor (1) are measured and the sensor (1) and/or an
electronic unit (3) cooperating with the sensor (1) is/are deactivated for as long as the
vibrations exceed a defined intensity and/or occur within a defined frequency band.
2. A method as claimed in claim 1, wherein the mechanical vibrations are measured
by means of one or more acceleration sensors (4, 5, 6).
3. A method as claimed in claim 2, wherein the acceleration sensors (4, 5, 6) are
disposed in the immediate proximity of the sensor (1).
4. A method as claimed in claim 1 to 3, wherein the acceleration sensors (4, 5, 6)
have different bandwidths and/or measuring directions.
5. A method as claimed in claim 4, wherein the bandwidth of the acceleration
sensors (4, 5, 6) ranges between 300 and 450 Hz.
6. A method as claimed in one or more of claims 1 to 5, wherein the housing (10)
and/or the printed-circuit board (7) is/are additionally constructed mechanically such that
they form only a minimum number of narrowly confined resonance ranges during
vibrational excitation.
7. A method as claimed in one or more of claims 1 to 6, wherein the printed-circuit board (7) is mounted in vibration-damping manner in holding members (8, 9).



ABSTRACT


Method of Operating Rate of Rotation Sensor
The invention discloses a method for operating a sensor (1), particularly, a yaw
rate sensor, which is housed inside a housing (10). In order to detect the dangerous
influence of mechanical vibrations upon the output measured value of the sensor (1), the
vibrations are sensed at the location of the sensor (1), and the sensor (1) or an electronic
device (3) interacting with the sensor (1) is switched off so long as the vibrations exceed
an established intensity. The method can be used, in particular, in a driving dynamics
control (FDR) of a road vehicle.

Documents:

02886-kolnp-2006 abstract.pdf

02886-kolnp-2006 claims.pdf

02886-kolnp-2006 correspondence others.pdf

02886-kolnp-2006 description (complete).pdf

02886-kolnp-2006 drawings.pdf

02886-kolnp-2006 form-1.pdf

02886-kolnp-2006 form-3.pdf

02886-kolnp-2006 form-5.pdf

02886-kolnp-2006 international publication.pdf

02886-kolnp-2006 international search report.pdf

02886-kolnp-2006 pct others.pdf

02886-kolnp-2006 priority document.pdf

02886-kolnp-2006-correspondence others-1.1.pdf

02886-kolnp-2006-gpa.pdf

2886-KOLNP-2006-(06-02-2013)-ANNEXURE TO FORM-3.pdf

2886-KOLNP-2006-(06-02-2013)-CORRESPONDENCE.pdf

2886-KOLNP-2006-(06-02-2013)-ENGLISH TRANSLATION OF PRIORITY DOCUMENT.pdf

2886-KOLNP-2006-(08-11-2013)-CORRESPONDENCE.pdf

2886-KOLNP-2006-(27-08-2013)-ABSTRACT.pdf

2886-KOLNP-2006-(27-08-2013)-AMANDED PAGES OF SPECIFICATION.pdf

2886-KOLNP-2006-(27-08-2013)-ANNEXURE TO FORM 3.pdf

2886-KOLNP-2006-(27-08-2013)-CLAIMS.pdf

2886-KOLNP-2006-(27-08-2013)-CORRESPONDENCE.pdf

2886-KOLNP-2006-(27-08-2013)-DRAWINGS.pdf

2886-KOLNP-2006-(27-08-2013)-FORM-1.pdf

2886-KOLNP-2006-(27-08-2013)-FORM-2.pdf

2886-KOLNP-2006-(27-08-2013)-OTHERS.pdf

2886-KOLNP-2006-(27-08-2013)-PA.pdf

2886-KOLNP-2006-(27-08-2013)-PETITION UNDER RULE 137.pdf

2886-KOLNP-2006-ASSIGNMENT.pdf

2886-KOLNP-2006-CORRESPONDENCE.pdf

2886-KOLNP-2006-EXAMINATION REPORT.pdf

2886-KOLNP-2006-FORM 18-1.1..pdf

2886-kolnp-2006-form 18.pdf

2886-KOLNP-2006-GPA.pdf

2886-KOLNP-2006-GRANTED-ABSTRACT.pdf

2886-KOLNP-2006-GRANTED-CLAIMS.pdf

2886-KOLNP-2006-GRANTED-DESCRIPTION (COMPLETE).pdf

2886-KOLNP-2006-GRANTED-DRAWINGS.pdf

2886-KOLNP-2006-GRANTED-FORM 1.pdf

2886-KOLNP-2006-GRANTED-FORM 2.pdf

2886-KOLNP-2006-GRANTED-FORM 3.pdf

2886-KOLNP-2006-GRANTED-FORM 5.pdf

2886-KOLNP-2006-GRANTED-LETTER PATENT.pdf

2886-KOLNP-2006-INTERNATIONAL PUBLICATION.pdf

2886-KOLNP-2006-INTERNATIONAL SEARCH REPORT & OTHERS.pdf

2886-KOLNP-2006-PA.pdf

2886-KOLNP-2006-PRIORITY DOCUMENT.pdf

2886-KOLNP-2006-REPLY TO EXAMINATION REPORT.pdf

2886-KOLNP-2006-TRANSLATED COPY OF PRIORITY DOCUMENT.pdf

abstract-02886-kolnp-2006.jpg


Patent Number 259052
Indian Patent Application Number 2886/KOLNP/2006
PG Journal Number 09/2014
Publication Date 28-Feb-2014
Grant Date 24-Feb-2014
Date of Filing 06-Oct-2006
Name of Patentee WABCO GMBH & CO.OHG
Applicant Address AM LINDENER HAFEN 21,30453 HANNOVER
Inventors:
# Inventor's Name Inventor's Address
1 BOLZMANN,OLIVER KREIGERSTRASSE 31,30161 HANNOVER
2 KUSTER,KLAUS FROBENIUSWEG 24,30355 HANNOVER
PCT International Classification Number B60T8/88; G01C19/56
PCT International Application Number PCT/EP2005/000727
PCT International Filing date 2005-01-26
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 102004018623.5 2004-04-16 Germany