DE102012202639A1 - Sensor arrangement i.e. steering angle sensor, for detection of steering angle at gear wheel in vehicle, has sensor determining covered distance of measuring element, where covered distance represents rotational angle of rotary component - Google Patents

Abstract

The arrangement (1) has a measuring element (20) coupled with a peripheral part of a rotary component (10) and connected with a distance sensor (26) for generating a signal that represents a rotational angle of the rotary component. The measuring element is designed as a movement converter that converts rotation (12) of the rotary component into translation (22) e.g. axial translation (22a) and tangential translation, of the measuring element. The sensor determines a covered distance of the measuring element, where the covered distance represents the rotational angle of the rotary component. The measuring element is designed as a pinion, a longitudinally and rotatably guided screw or a longitudinally movably guided rack gear. The distance sensor is designed as an eddy current sensor (26.1, 26.2), a capacitive sensor or an ultrasonic sensor.

Description

State of the art

The invention is based on a sensor arrangement for detecting rotational angles on a rotating component in a vehicle according to the preamble of the independent patent claim 1.

In the known steering angle sensor, a counting wheel for determining the number of revolutions of the steering wheel is scanned without contact by means of magnetic field sensors. Such a system has the disadvantage that when the ignition is switched off, a quiescent current must be provided in order to be able to detect a rotation of the steering wheel when the ignition is switched off. With permanent non-use of the vehicle, this leads to an undesirable emptying of the vehicle battery. If such a quiescent current is not provided, the steering angle can no longer be clearly determined if the steering wheel is turned when the ignition is switched off or the battery is disconnected.

In the published patent application DE 10 2007 052 162 A1 For example, a measuring device for contactless detection of a rotation angle or a linear path and a pedal module will be described with such a measuring device. The detected angle of rotation or the detected linear path is due to a relative movement between at least two bodies, which are biased by spring means against each other in their initial position. The spring means comprise windings of an electrically conductive material and the relative movement of the body causes a change in length of the spring means. It is envisaged that at least part of the turns of the spring means are covered by a magnetic coil which is included together with at least one capacitor of a resonant circuit. In addition, an evaluation device is provided, which in response to the change in the resonant frequency of the resonant circuit, which is based on the caused by the relative movement of the body length change of the spring means, a signal that can be evaluated for detecting and calculating the relative movement. In order to convert the rotational movement of an accelerator pedal lever relative to a bearing block in a simpler linear motion with respect to the measuring principle, the spring elements can with its one end to a bearing block formed on the support surface and the other end at a with respect to a pivot axis between the accelerator lever and the Bearing support a lever arm forming support arm of the accelerator pedal lever.

In the published patent application DE 10 2008 011 448 A1 For example, an arrangement for detecting a rotation angle will be described. The arrangement described comprises encoders and sensors which, as a function of a rotation angle change of a rotating component, detect changes in a physical variable produced by the encoders as signals which can be evaluated digitally. The rotating member has at least one coupled to its circumference, rotating by its rotation satellites small scale, preferably with an angle sensor which drives via an axially coupled hypocycloidal a likewise rotating Hyperzykloidscheibe or Hypozykloidzahnrad whose speed of rotation is undercut by the Hypozykloidgetriebe such that From this, a number of revolutions of the rotating component and the absolute steering angle over several revolutions of the steering shaft with a revolution sensor system can be determined.

Disclosure of the invention

The sensor unit according to the invention for a vehicle with the features of independent claim 1 has the advantage that is always possible by the transfer of the rotational movement in a mechanical path change a unique rotational position even with multiple revolutions of the rotating component. Advantageously, the failure of the electronics, the rotational movement in the mechanical changed path position is maintained. Due to the mechanical path change, the correct absolute rotation angle is available even after the ignition has been switched off or the battery has been disconnected, with at the same time particularly reliable operation or particularly reliable detection of the rotation angle being possible by means of distance detection. Another advantage can be the mechanical simplification, which can lead to cost savings. Preferably, the sensor arrangement according to the invention can be used for determining the steering angle of a vehicle. In this case, the rotating component or gear is preferably rotatably coupled to the steering wheel or the steering column of the vehicle. Embodiments of the present invention convert the steering movement into a path change, which can be detected without contact by means of a distance measurement and converted into a steering angle.

Embodiments of the present invention provide a sensor assembly for detecting rotational angles on a rotating component in a vehicle. The rotating component is coupled at its circumference to a transmitter which, in conjunction with at least one sensor, generates a signal representing the angle of rotation of the rotating component. According to the invention the transmitter is designed as a motion converter, which controls the rotation of the rotating Component in a translation of the transmitter converts, wherein the at least one sensor determines the distance traveled by the transmitter, which represents the rotation angle of the rotating component.

The measures and refinements recited in the dependent claims, advantageous improvements of the independent claim 1 sensor arrangement for detecting rotation angles on a rotating component in a vehicle are possible.

It is particularly advantageous that the transmitter can convert the rotation of the rotating component into an axial translation of the transmitter with respect to the rotating component. The transmitter can be performed, for example, as a pinion, which is longitudinally movably guided on a bolt with a corresponding external thread via an internal thread and positioned so that a first ring gear of the rotating component meshes with a second ring gear of the pinion. As a result, the rotational movement transmitted to the pinion from the rotating component can be converted into a change in the height of the sensor designed as a pinion, wherein the change in height of an upper and / or lower end face of the transmitter can be measured via the at least one sensor as a covered path. Advantageously, a resolution of the determined angle of rotation of the rotating component via a transmission ratio of the preferably designed as a gear rotating component and the transmitter and / or a pitch of the internal thread and / or the external thread of the bolt can be specified. Through the thread, the height change can be decoupled from the gear ratio additional adapted to the characteristic of the at least one sensor for determining the distance traveled.

In an advantageous embodiment of the sensor arrangement according to the invention, the transmitter can convert the rotation of the rotating component into a tangential translation of the transmitter with respect to the rotating component. The transmitter can be performed, for example, as a longitudinally and rotatably guided screw, which is positioned so that a first ring gear of the rotating component meshes a thread of the screw. As a result, the rotational movement of the rotating component can be converted into a rectilinear movement of the sensor designed as a screw, wherein the distance covered by a first and / or second end face of the transmitter can be measured via the at least one sensor. Advantageously, a resolution of the determined angle of rotation of the rotating component over a number of teeth of the first ring gear of the rotating component and / or a pitch of the thread of the screw can be specified.

In an alternative advantageous embodiment of the sensor arrangement according to the invention, the transmitter can be designed as a longitudinally movably guided rack, which is positioned so that a first ring gear of the rotating component meshes with a tooth region of the rack. As a result, the rotational movement of the rotating component can be converted into a rectilinear movement of the sensor designed as a rack, wherein the distance covered by a first and / or second end face of the transmitter can be measured via the at least one sensor. Advantageously, a resolution of the determined angle of rotation of the rotating component over a number of teeth of the first ring gear of the rotating component and / or via a pitch of the tooth portion of the rack can be specified.

In a further advantageous embodiment of the sensor arrangement according to the invention, the at least one sensor can be designed as a distance sensor, which determines the distance of the transmitter to a reference point, wherein at least one sensor is arranged at the transmitter and / or at the reference point. Preferably, the distance of a first and / or second end face of the transmitter is measured to the reference point. Furthermore, at least two sensors for determining the distance between a surface or end face of the transmitter and corresponding reference points can be provided. In this case, an evaluation and control unit by evaluating sensor signals, which provide the at least two sensors available, advantageously determine a tilt of the transmitter. In addition, the use of a plurality of sensors advantageously allows a redundant determination of the angle of rotation on a rotating component. The at least one sensor can be designed, for example, as an eddy-current sensor, which determines the distance via a change in the associated magnetic field, and / or as a capacitive sensor, which determines the distance via a change in an electric field, and / or as an ultrasonic sensor and / or as an optical sensor which determine the distance, for example via a signal delay measurement. These embodiments enable a cost effective implementation of the distance measurement. Of course, other distance measuring techniques known to those skilled in the art may also be implemented.

In a further advantageous embodiment of the sensor arrangement according to the invention at least two sensors are provided, which with an evaluation and control unit Form differential distance sensors. In this case, at least one first sensor determines the distance of the transmitter to a first reference point, and at least one second sensor determines the distance of the transmitter to a second reference point. For example, at least one first distance sensor can measure the distance of the first end face of the transmitter to the first reference point, and at least one second distance sensor can measure the distance of a second end face of the transmitter to the second reference point. This advantageously makes it possible to compensate for disturbing influences, such as, for example, a temperature change, etc. In addition, the use of a plurality of sensors advantageously enables a redundant determination of the angle of rotation on a rotating component.

Embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description. In the drawings, like reference numerals designate components that perform the same or analog functions.

Brief description of the drawings

1 shows a schematic perspective schematic representation of a sensor arrangement according to the invention.

2 shows a schematic perspective view of a first embodiment of a sensor arrangement according to the invention in a first position.

3 shows a schematic perspective view of the first embodiment of a sensor arrangement according to the invention in a second position.

4 shows a schematic perspective view of a second embodiment of a sensor arrangement according to the invention in a first position.

5 shows a schematic perspective view of the second embodiment of a sensor arrangement according to the invention in a second position.

6 shows a schematic perspective view of a third embodiment of a sensor arrangement according to the invention in a first position.

7 shows a schematic perspective view of the third embodiment of a sensor arrangement according to the invention in a second position.

8th shows a schematic perspective view of a fourth embodiment of a sensor arrangement according to the invention in a first position.

9 shows a schematic perspective view of the fourth embodiment of a sensor arrangement according to the invention in a second position.

Embodiments of the invention

How out 1 to 9 can be seen include embodiments of a sensor arrangement according to the invention 1 . 1a . 1b . 1c . 1d for detecting angles of rotation on a rotating component 10 in a vehicle a transmitter 20 and at least one sensor 26 . 26a . 26b , whose output signal from an evaluation and control unit 30 . 30a is evaluated. The rotating component 10 is at its periphery with the transmitter 20 coupled, which in conjunction with the at least one sensor 26 . 26a . 26b a the angle of rotation of the rotating component 10 representing signal generated and to the evaluation and control unit 30 . 30a outputs. According to the invention, the transmitter 20 designed as a motion converter, which rotation 12 of the rotating component 10 in a translation 22 of the transmitter 20 converts, wherein the at least one sensor 26 . 26a . 26b the distance traveled by the transmitter 20 determines which angle of rotation of the rotating component 10 represents.

The transmitter 20 can the rotation 12 of the rotating component 10 in an axial translation 22a of the transmitter 20 with respect to the rotating component 10 convert as described below with reference to 1 to 3 and 8th and 9 is described. Alternatively, the transmitter 20 the rotation 12 of the rotating component 10 in a tangential translation 22b of the transmitter 20 with respect to the rotating component 10 convert as described below with reference to 4 to 7 is described. To a game reduction of the transmitter 20 the transmitter can be reached 20 , For example, via at least one spring pin, not shown, are loaded with a spring force.

In the illustrated embodiments, the at least a sensor 26 . 26a . 26b designed as a distance sensor, which determines the distance 24 . 24a . 24b of the transmitter 20 determined to a reference point. Here, the at least one sensor 26 . 26a . 26b at the transmitter 20 and / or arranged at the reference point. In the illustrated embodiments, the at least one sensor 26 . 26a . 26b fixed at the reference point. Preferably, the at least one sensor 26 . 26a . 26b designed as eddy current sensor and / or as a capacitive sensor and / or as an ultrasonic sensor and / or as an optical sensor, since this allows a cost-effective implementation of the distance measurement. Of course, other distance measuring methods known to those skilled in the art can also be used to determine the distance covered by the transmitter 20 be implemented.

Embodiments of the sensor arrangement according to the invention 1 . 1a . 1b . 1c . 1d For example, they can be used as a steering angle sensor for determining the steering angle of a vehicle. Here is the rotating component 10 for example, designed as a gear and preferably rotatably coupled to a steering wheel and / or a steering column of the vehicle.

By transferring the rotation 12 or steering movement in a mechanical translation 22 , which is determined by a distance measurement, is always a clear rotational position or a unique steering angle even with multiple revolutions of the steering wheel possible. Also remains in the failure of the electronics, the rotational movement in the mechanical changed height position. Due to the mechanical translation 22 is also after switched off ignition or disconnected battery the correct absolute angle of rotation or steering angle available, at the same time a particularly safe operation or a particularly secure detection of the rotation angle or steering angle by means of the distance detection is possible.

In the schematic representation of 1 is the rotating component 10 over a first sprocket 14 with a second sprocket 20.1 of the transmitter 20 coupled and transmits the rotation 12 on the transmitter 20 which is the rotation 12 or rotational movement in an axial translation 22a in the form of a height change of the transmitter 20 transforms. One above a face of the transmitter 20 arranged distance sensor 26 , which, for example, two eddy current sensors 26.1 . 26.2 comprising, each having a coil for generating corresponding magnetic fields 28 may have a change in distance 24 between the distance sensor 26 and the face of the transmitter 20 Detect contactless and a corresponding output signal to the evaluation and control unit 30 output. By the distance change 24 become the of the two eddy current sensors 26.1 . 26.2 generated magnetic fields 28 influenced, so that, for example, in conjunction with each fixed capacity detected a corresponding change in frequency and the evaluation and control unit 30 can be evaluated for distance determination. The evaluation and control unit 30 evaluates the output signal of the distance sensor 26 out and can on the rotation angle of the rotating component 10 shut down. By evaluating sensor signals, which from the two eddy current sensors 26.1 . 26.2 can be made available to the evaluation and control unit 30 advantageously a tilt of the transmitter 20 determine or perform a redundant determination of the rotation angle. For pure distance determination, however, is a distance sensor 26 or an eddy current sensor 26.1 . 26.2 sufficient.

How out 2 and 3 is further apparent, is in the illustrated first embodiment of the sensor arrangement according to the invention 1a the transmitter 20 as a pinion 20a executed, which longitudinally movable on an internal thread on a bolt 21 with a corresponding external thread 21a is guided. The as pinion 20a executed transducers 20 is positioned so that a first sprocket 14 of the gear designed as a rotating component 10 a second sprocket 20.1 of the pinion 20a combs. This will cause the rotation 12 of the rotating component 10 on the as a pinion 20a executed transmitter 20 transmitted, which by the transmitted rotary motion its position in the axial direction 22a changes upwards. As if from a comparison between 2 and 3 can be seen, reduced by the illustrated direction of rotation 12 of the rotating component 10 the distance 24 between the upper end face of the pinion 20a executed transmitter 20 and above the transmitter 20 arranged distance sensor 26 , A resolution of the determined angle of rotation of the rotating component 10 can for example via a transmission ratio of the rotating component 10 and that as a pinion 20a executed transmitter 20 and / or over a pitch of the internal thread and / or the external thread 21a of the bolt 21 be specified.

How out 4 and 5 is further apparent, is in the illustrated second embodiment of the sensor arrangement according to the invention 1b the transmitter 20 as a longitudinally and rotatably guided screw 20b executed, which is positioned so that a first sprocket 14 of the rotating component 10 a thread 21b the screw 20b combs. This will cause the rotation 12 of the rotating component 10 on the as a screw 20b executed transmitter 20 which transmits its position in the tangential direction 22b changes to the left. As if from a comparison between 4 and 5 can be seen, reduced by the illustrated direction of rotation 12 of the rotating component 10 the distance 24 between the left end face of the screw 20b executed transmitter 20 and axially spaced from the transmitter 20 arranged distance sensor 26 , A resolution of the determined angle of rotation of the rotating component 10 can have a tooth count of first sprocket 14 of the rotating component 10 and / or over a pitch of the thread 21b the screw 20b be specified.

How out 6 and 7 is further apparent, is in the illustrated third embodiment of the sensor arrangement according to the invention 1c the transmitter 20 as a longitudinally moveable guided rack 20c executed, which is positioned so that a first sprocket 14 of the rotating component 10 a tooth area 21c the rack 20c combs. This will cause the rotation 12 of the rotating component 10 on the rack 20c executed transmitter 20 which transmits its position in the tangential direction 22b changes to the left. As if from a comparison between 6 and 7 can be seen, reduced by the illustrated direction of rotation 12 of the rotating component 10 the distance 24 between the left end face of the rack 20c executed transmitter 20 and axially spaced from the transmitter 20 arranged distance sensor 26 , A resolution of the determined angle of rotation of the rotating component 10 can have a number of teeth of the first sprocket 14 of the rotating component 10 and / or over a pitch of the tooth area 21c the rack 20c be specified.

This in 8th and 9 illustrated fourth embodiment of the sensor arrangement according to the invention substantially corresponds to the in 2 and 3 illustrated first embodiment, so that is omitted here a repetitive description of construction or functionally identical components and will be discussed only on the differences between the embodiments. In contrast to the first embodiment form in the fourth embodiment, two distance sensors 26a . 26b with the evaluation and control unit 30a a differential distance sensor. Here is a first distance sensor 26a above the pinion 20a executed transmitter 20 arranged and determines a first distance 24a of the transmitter 20 to a first reference point. A second distance sensor 26b is below the pinion 20a executed transmitter 20 arranged and determines a second distance 24b of the transmitter 20 to a second reference point. As if from a comparison between 8th and 9 can be seen, reduced by the illustrated direction of rotation 12 of the rotating component 10 the first distance 24a between the upper end face of the pinion 20a executed transmitter 20 and above the transmitter 20 arranged first distance sensor 26a while the second distance 24b between the lower end face of the pinion 20a executed transmitter 20 and below the transmitter 20 arranged second distance sensor 26b increased. This differential distance sensor advantageously makes it possible to compensate for disturbing influences, such as temperature, etc. In addition, the use of multiple sensors makes it possible 26a . 26b advantageously a redundant determination of the angle of rotation on the rotating component 10 ,

The in conjunction with the as a pinion 20a executed transmitter 20 described differential distance sensor can be analogous to the screw 20b or rack 20c executed transmitter 20 be transmitted.

Embodiments of the present invention provide a sensor arrangement for detecting rotational angles on a rotating component in a vehicle, which always provide an unambiguous rotational position by transferring the rotational movement into a mechanical path change even with multiple revolutions of the rotating component. Advantageously, when the electronics fail, the rotational movement in the mechanical changed path position is maintained. Due to the mechanical path change, the correct absolute rotation angle is available even after the ignition has been switched off or the battery has been disconnected, with at the same time particularly reliable operation or particularly reliable detection of the rotation angle being possible by means of distance detection.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102007052162 A1 [0003]
• DE 102008011448 A1 [0004]

Claims (14)

Sensor arrangement for detecting rotational angles on a rotating component in a vehicle, which is provided at its circumference with a measuring transducer ( 20 ), which in conjunction with at least one sensor ( 26 . 26a . 26b ) a rotation angle of the rotating component ( 10 ), characterized in that the transmitter ( 20 ) is designed as a motion converter, which rotation ( 12 ) of the rotating component ( 10 ) into a translation ( 22 ) of the transmitter ( 20 ), wherein the at least one sensor ( 26 . 26a . 26b ) the distance traveled by the transmitter ( 20 ), which determines the angle of rotation of the rotating component ( 10 ). Sensor arrangement according to claim 1, characterized in that the transmitter ( 20 ) the rotation ( 12 ) of the rotating component ( 10 ) in an axial translation ( 22a ) of the transmitter ( 20 ) with respect to the rotating component ( 10 ) converts. Sensor arrangement according to claim 1 or 2, characterized in that the transmitter ( 20 ) as a pinion ( 20a ) is executed, which is longitudinally movable on a bolt via an internal thread ( 21 ) with a corresponding external thread ( 21a ) and positioned so that a first sprocket ( 14 ) of the rotating component ( 10 ) a second sprocket ( 20.1 ) of the pinion ( 20a ) combs. Sensor arrangement according to claim 3, characterized in that a resolution of the determined angle of rotation of the rotating component ( 10 ) via a transmission ratio of the rotating component ( 10 ) and the transmitter ( 20 ) and / or over a pitch of the internal thread and / or the external thread ( 21a ) of the bolt ( 21 ) is given. Sensor arrangement according to claim 1, characterized in that the transmitter ( 20 ) the rotation ( 12 ) of the rotating component ( 10 ) into a tangential translation ( 22b ) of the transmitter ( 20 ) with respect to the rotating component ( 10 ) converts. Sensor arrangement according to claim 1 or 5, characterized in that the transmitter ( 20 ) as longitudinally and rotatably guided screw ( 20b ), which is positioned so that a first sprocket ( 14 ) of the rotating component ( 10 ) a thread ( 21b ) of the screw ( 20b ) combs. Sensor arrangement according to claim 6, characterized in that a resolution of the determined angle of rotation of the rotating component ( 10 ) over a number of teeth of the first sprocket ( 14 ) of the rotating component ( 10 ) and / or over a pitch of the thread ( 21b ) of the screw ( 20b ) is given. Sensor arrangement according to claim 1 or 5, characterized in that the transmitter ( 20 ) as a longitudinally movable guided rack ( 20c ), which is positioned so that a first sprocket ( 14 ) of the rotating component ( 10 ) a tooth area ( 21c ) of the rack ( 20c ) combs. Sensor arrangement according to claim 8, characterized in that a resolution of the determined rotational angle of the rotating component ( 10 ) over a number of teeth of the first sprocket ( 14 ) of the rotating component ( 10 ) and / or via a division of the tooth area ( 21c ) of the rack ( 20c ) is given. Sensor arrangement according to one of claims 1 to 9, characterized in that the at least one sensor ( 26 . 26a . 26b ) is designed as a distance sensor, which determines the distance ( 24 . 24a . 24b ) of the transmitter ( 20 ) to a reference point, wherein at least one sensor ( 26 . 26a . 26b ) on the transmitter ( 20 ) and / or arranged at the reference point. Sensor arrangement according to claim 10, characterized in that at least two sensors ( 26.1 . 26.2 ) for determining the distance ( 24 . 24a . 24b ) between a surface of the transmitter ( 20 ) and corresponding reference points are provided, wherein an evaluation and control unit ( 30 . 30a ) by evaluating sensor signals which the at least two sensors ( 26.1 . 26.2 ), a tilt of the transmitter ( 20 ). Sensor arrangement according to claim 11, characterized in that the at least one sensor ( 26 . 26a . 26b ) as eddy current sensor ( 26.1 . 26.2 ) and / or as a capacitive sensor and / or as an ultrasonic sensor and / or as an optical sensor. Sensor arrangement according to one of claims 10 to 12, characterized in that at least two sensors ( 26a . 26b ) with an evaluation and control unit ( 30a ) form a differential distance sensor system, wherein at least one first sensor ( 26a ) a first distance ( 24a ) of a first surface of the transmitter ( 20 ) to a first reference point, and at least one second sensor ( 26b ) a second distance ( 24b ) of a second surface of the transmitter ( 20 ) is determined to a second reference point. Sensor arrangement according to one of claims 1 to 13, characterized in that the rotating component ( 10 ) for determining a steering angle in the vehicle rotatably coupled to a steering wheel or a steering column.

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