Device for a vehicle for detecting an activation action in a detection region
The invention relates to a device ( 10 ) for a vehicle ( 1 ) for detecting an activation action in a detection region ( 51 ), and in particular for mounting on a vehicle part ( 5 ), in order to activate a function of the vehicle ( 1 ) depending on the detection, comprising: a multi-layer printed circuit board ( 20 ), at least one electrically conductive sensor element ( 31 ) for capacitive sensing in the detection region ( 51 ), wherein the sensor element ( 31 ) is arranged on the printed circuit board ( 20 ), at least two shielding elements ( 40 ) for shielding ( 41 ) for the sensing.
1. A device for a vehicle for detecting an activation action in a detection region in order to activate a function of the vehicle depending on the detection, comprising:
a multi-layer printed circuit board,
at least one electrically conductive sensor element for capacitive sensing in the detection region, wherein the sensor element is arranged on the printed circuit board, and
at least two shielding elements for shielding for the sensing,
wherein:
the shielding elements are arranged at different layers of the printed circuit board, wherein one of the shielding elements surrounds the sensor element at a first layer in order to provide the shielding in different directions; and
the shielding elements are distributed at the layers in such a way that the shielding limits the detection region in three directions orthogonal to each other and surrounds the detection region at least predominantly in one plane.
2. The device according to claim 1 , wherein the shielding element surrounds the sensor element at least predominantly at the first layer.
3. The device according claim 1 , wherein one of the shielding elements at a second layer is congruent with the sensor element at the first layer.
4. The device according to claim 3 , wherein an electric ground extends flat at the second layer adjacent to the shielding element at the second layer.
5. The device according to claim 1 , wherein one of the shielding elements at a third layer extends flat and unilaterally to the sensor element at the first layer in order to provide the shielding unilaterally.
6. The device according to claim 1 , wherein the shielding elements are connected to one another at the different layers via through connections and are thus provided with equal potential.
7. The device according to claim 1 , wherein the shielding elements are electrically separated from each other at the different layers in order to comprise different electric potentials.
8. The device according to claim 1 , wherein a processing device is electrically connected to the shielding elements in order to operate the shielding elements to provide an active shielding, in which an electric potential of the shielding elements is adjusted depending on an electric potential of the sensor element.
9. The device according to claim 1 , wherein a processing device is arranged on the printed circuit board and is electrically connected to the sensor element for charge transfers in order to evaluate a variable electric capacitance on the basis of the charge transfers and thereby provide the capacitive sensing.
10. The device according to claim 9 , wherein the processing device is designed to perform the detection of the activation action in such a way that at least an approach or a gesture of a user is detected on the basis of the evaluation of the capacitance.
11. The device according to claim 9 , wherein the sensor element is formed at the first layer adjacent to the detection region, wherein the first layer is provided as an outer layer of the printed circuit board to provide the variable electric capacitance via the sensor element in such a way that the capacitance is dependent on the activation action in the detection region.
12. The device according to claim 1 , wherein a communication means is arranged at the layers of the printed circuit board.
13. A door handle for a vehicle which comprises a device according to claim 1 as the vehicle part.
14. A method for detecting an activation action in a detection region at a vehicle in order to activate a function of the vehicle depending the detection, wherein the following steps are carried out:
performing a capacitive sensing in the detection region by an electrically conductive sensor element at a multi-layer printed circuit board, and
generating a shielding for the sensing by at least two shielding elements on the printed circuit board,
wherein:
the shielding elements are arranged at different layers of the printed circuit board, wherein one of the shielding elements surrounds the sensor element at a first layer so that the shielding is provided in different directions; and
the shielding elements are distributed at the layers in such a way that the shielding limits the detection region in three directions orthogonal to each other and surrounds the detection region at least predominantly in one plane.