Sensor Device

Abstract

The invention relates to a sensor device (100), in particular for a vehicle, comprising: a capacitive sensor unit (10) and a coil unit (20) which surrounds the capacitive sensor unit (10) at least partially, preferably geometrically. For this purpose, it is provided according to the invention that the capacitive sensor unit (10) has at least one first, in particular linear, sensor element (11), which is aligned essentially along a first geodesic (G1) of the coil unit (20).

Claims

1-19. (canceled)

20. A sensor device, comprising: a capacitive sensor unit and a coil unit which at least partially, surrounds the capacitive sensor unit, wherein the capacitive sensor unit has at least one first, sensor element which is aligned essentially along a first geodesic of the coil unit.

21. The sensor device according to claim 20, wherein at least the sensor device is arranged on a printed circuit board, or the capacitive sensor unit and the coil unit are arranged at least on a side or in a conductive layer of a printed circuit board.

22. The sensor device according to claim 20, wherein at least the capacitive sensor unit is at least partially, surrounded by the coil unit, or the coil unit is configured at least in part at least to shield or to shape a capacitive field of the capacitive sensor unit, or the capacitive sensor unit is off when the coil unit is in sensing operation, and that the coil unit is off when the capacitive sensor unit is in sensing operation.

23. The sensor device according to claim 20, wherein the coil unit has at least one, winding or loop antenna.

24. The sensor device according to claim 20, wherein at least the winding is essentially at least loop-shaped or circular, or the winding is aligned along an outer edge of a printed circuit board, or the winding determines a plane in which the capacitive sensor unit is arranged.

25. The sensor device according to claim 20, wherein at least the capacitive sensor unit or the coil unit have at least line-shaped or band-shaped sensor elements, or sensor elements at least of the capacitive sensor unit or the coil unit are produced photolithographically.

26. The sensor device according to claim 20, wherein the first sensor element is configured as a feed line for the capacitive sensor unit.

27. The sensor device according to claim 20, wherein at least the capacitive sensor unit comprises at least a second sensor element for sensing a capacitive change of the environment, or the capacitive sensor unit comprises a plurality of second sensor elements for sensing a capacitive change in the environment.

28. The sensor device according to claim 20, wherein the second sensor elements are at least arranged in a star-shaped, rib-shaped, ridge-shaped or comb-shaped manner.

29. The sensor device according to claim 20, wherein at least the at least one second sensor element or the second sensor elements is/are substantially aligned along geodesics of the coil unit.

30. The sensor device according to claim 20, wherein at least the at least one second sensor element or the second sensor elements extend from an end or section of the first sensor element.

31. An electronic unit for actuating a movable part, such as a door, a flap or a cover, of a vehicle, wherein the electronic unit comprises at least one sensor device according to claim 20.

32. The electronic unit according to claim 31, wherein the capacitive sensor unit is configured for detecting an approach of a user to the sensor device, and the coil unit is configured for at least communicating with a vehicle-side security system or a user-side mobile handheld device.

33. A door handle for a vehicle, wherein the door handle comprises at least one electronic unit according to claim 31, and wherein the electronic unit is arranged in a recess in the door handle.

34. A method for manufacturing a sensor device, comprising: a capacitive sensor unit and a coil unit at least partially surrounding the capacitive sensor unit, wherein the capacitive sensor unit is implemented with at least one first sensor element, and that the at least one first sensor element is substantially aligned along a first geodesic of the coil unit.

35. The method according to claim 34, wherein at least the capacitive sensor unit or the coil unit are/is configured at least with linear or band-shaped sensor elements, or the sensor elements at least of the capacitive sensor unit or the coil unit are produced photolithographically.

36. The method according to claim 34, at least the capacitive sensor unit is implemented with at least one second sensor element for sensing a capacitive change of the environment, or the capacitive sensor unit is implemented with a plurality of second sensor elements to sense a capacitive change in the environment.

37. The method according to claim 34, wherein the second sensor elements are aligned in at least a star-shaped, rib-shaped, ridge-shaped or comb-shaped manner.

38. The method according to claim 34, wherein at least the at least one second sensor element or the second sensor elements is/are aligned substantially along geodesics of the coil unit.

Description

[0045] Further advantages, features and details of the invention will be apparent from the following description, in which embodiments of the invention are described in detail with reference to the drawings. In this connection, the features mentioned in the claims and in the description may each be essential to the invention individually or in any combination. Showing:

[0046] FIG. 1 a schematic representation of a coil unit according to the invention,

[0047] FIG. 2 a schematic representation of a sensor device according to the invention,

[0048] FIG. 3 a schematic representation of a sensor device according to the invention, and

[0049] FIG. 4 a schematic representation of a door handle of a vehicle according to the invention.

[0050] In the following figures, the identical reference signs are used for the same technical features, even from different embodiments. As a rule, the reference signs of the same embodiments are described only once.

[0051] FIG. 1 shows an exemplary sensor device 100 with a coil unit 20 in the sense of the invention. The coil unit 20 can be used for communicating with a safety system 2 of a vehicle F and/or a user-side mobile hand-held device, which are shown schematically below in FIG. 4. Such a sensor device 100 may form part of an electronic unit 1, which is configured, for example, to actuate a movable part T, such as a door, a flap or a lid, of the vehicle. For detecting a presence of a user, such a sensor device 100 is implemented with a capacitive sensor unit 10, exemplarily shown in FIGS. 2 and 3.

[0052] The capacitive sensor unit 10 is implemented with sensor elements 11, 12 in the form of line-shaped and/or tape-shaped conductor tracks, which are printed on a printed circuit board 101. To save space, the coil unit 20 is also arranged geometrically around the capacitive sensor unit 10 on the same printed circuit board 101 (cf. FIGS. 2 and 3). Due to the close arrangement of the coil unit 20 next to the capacitive sensor unit 10, eddy currents may occur in the capacitive sensor unit 10.

[0053] The invention proposes an improved sensor device 100, in particular for a vehicle F, exemplarily shown in FIGS. 2 and 3, in which the induction of eddy currents, even on a limited area of a printed circuit board 101, is reduced. Furthermore, the invention proposes an improved electronic unit 1 for actuating a movable part T, such as for example a door, a flap or a lid, of a vehicle F, with a corresponding sensor device 100, shown schematically in FIG. 4. Moreover, the invention proposes a door handle G for a vehicle F with a corresponding electronic unit 1, also shown schematically in FIG. 4. Furthermore, the invention proposes a method for manufacturing a corresponding sensor device 100, in particular for a vehicle F, the procedure of which is explained with reference to FIGS. 1 to 3.

[0054] In the sensor device 100, the invention provides that the capacitive sensor unit 10 comprises at least one first, in particular linear, sensor element 11, which is substantially aligned along a first geodesic G1 of the coil unit 20, as shown in FIGS. 2 and 3.

[0055] The capacitive sensor unit 10 in the context of the invention has at least one first line-shaped sensor element 11 and at least one second line-shaped sensor element 12, but preferably a plurality of second sensor elements 12, which can extend from an end E1 (cf. FIG. 3) or section A1 (cf. FIG. 2) of the first sensor element 11, which end E1 or section A1 is located in particular inside the coil unit 20.

[0056] The at least one first linear sensor element 11 and the at least one second linear sensor element 12, but preferably a plurality of second sensor elements 12, form a conductive path structure within the coil unit 20.

[0057] The coil unit 20 may be configured as an inductive sensor unit with at least one LDC coil, which can detect a movement of a metallic element of a few millimeters or even micrometers with respect to the at least one LDC coil. Moreover, in the sense of the invention, the coil unit 20 may be implemented as an electromagnetic sensor unit with at least one NFC coil, which may be used for contactless exchange of data by means of electromagnetic induction through loosely coupled coils. In both cases, the coil unit 20 may comprise one, in particular only one, winding 21 and/or loop antenna, as shown in FIGS. 1 to 3.

[0058] The coil unit 20 in the form of a winding 21 and/or loop antenna generates a magnetic field when energized, as indicated in FIG. 1. The magnetic field lines M wind around the energized winding 21 or loop antenna of the coil unit 20. These magnetic field lines M can in turn induce eddy currents in internal sensor elements 11, 12 of the sensor unit 10.

[0059] Here, the geometry of the sensor elements 11, 12 of the capacitive sensor unit 10 can be adapted on the basis of the magnetic field of the coil unit 20 in such a way that the induction of the eddy currents within the capacitive sensor unit 10 is at least reduced, preferably minimized.

[0060] Based on the known geometry of the coil unit 20, the magnetic field lines M around the winding 21 can be determined or predicted. Within the winding 21 again isolines I can be determined, on which the magnetic field strength of the magnetic field of the energized coil unit 20 has the same value. As FIG. 1 further indicates, these isolines I are arranged substantially concentrically to the winding 21 of the coil unit 20. If further conductive tracks or loop contacts are arranged along the isolines 21, the induction currents will be formed therein with a uniform current intensity I Winder.

[0061] Knowing the isolines I, geodesics G1, G2 are now determined or predicted for the coil unit 20 and the magnetic field of the coil unit 20, respectively. The geodesics G1, G2 of the coil unit 20 are lines shown in FIG. 1 which are perpendicular or orthogonal to the isolines I of the magnetic field of the coil unit 20 at each point. In other words, the geodesics G1, G2 are the lines which depart from the center of the winding 21 of the coil unit 20 in a star shape (similar to a spider web) and which intersect the isolines I and the winding 21 of the coil unit 20 at each point at a right angle. Along the geodesics G1, G2, minimal eddy currents can be induced within the sensor elements 11, 12 of the capacitive sensor unit 10, since along the geodesics G1, G2 only the cross-section of the line-shaped sensor elements 11, 12 is available for the formation of the induced eddy currents.

[0062] The at least one first sensor element 11 may be listed, for example, in the form of a lead for the capacitive sensor unit 10, as illustrated by FIGS. 2 and 3. Furthermore, the capacitive sensor unit 10 may comprise a rib structure of the second sensor elements 12, as indicated by FIG. 2. Such parallel conductive paths can be produced particularly easily. Alternatively, the second sensor elements 12 can also run along further geodesics of the coil unit 20, as shown in FIG. 3, in order to further reduce the eddy currents within the capacitive coil unit 10.

[0063] Thus, with the help of the invention, cross influences and/or interferences between the coil unit 20 and the capacitive sensor unit 10 can be minimized, even on a smallest area. Thereby, the sensitivity, the resolution and the geometrical design of the sensor device 100 can be improved in an advantageous way and the safety in the operation of the sensor device 100 can be significantly increased.

[0064] As further shown in FIGS. 2 and 3, the sensor device 100 may be disposed on a printed circuit board 101 to provide a compact and easy-to-use sensor device 100.

[0065] Furthermore, FIGS. 2 and 3 show that the capacitive sensor unit 10 and the coil unit 20 can be arranged on one side, preferably on an outer surface and/or in a conductive layer of the printed circuit board 101. In this way, the detection fields of the capacitive sensor unit 10 and the coil unit 20 can be aligned in the same direction with respect to the printed circuit board, for example away from the vehicle F.

[0066] In the context of the invention, the capacitive sensor unit 10 and the coil unit 20 may be photolithographically printed on the printed circuit board 101. In a photolithographic printing process, a thin layer of a photosensitive photoresist is applied to the surface of a printed circuit board 101 that is fully metallized, for example, with a Cu layer. After exposing the photoresist through a mask having a desired layout of the capacitive sensor unit 10 and the coil unit 20, either the exposed or unexposed portions of the resist are dissolved in a suitable developer solution, depending on the photoresist used, and thus removed. The thus treated circuit board 101 is then immersed in a suitable etching solution in which only the exposed portion of the metallized surface is attacked, leaving the portions of the circuit board 101 covered by the photoresist intact.

[0067] As shown in FIG. 2, the capacitive sensor unit 10 is largely, preferably completely, enclosed by the coil unit 20. From the supply line of the capacitive sensor unit 10, only one line leads to a schematically shown control unit 102, which takes over the evaluation of the detection by the sensor device 100.

[0068] In this regard, the control unit 102 may be implemented as a dedicated control unit 102 for the sensor device 100 or as part of a central control unit 102 in a vehicle F.

[0069] Another advantage of arranging the coil unit 20 around the capacitive sensor unit 10 may be that the coil unit 20, at least in a non-energized rest mode, may serve to shield and/or shape a capacitive field of the capacitive sensor unit 10.

[0070] Advantageously, it is further conceivable that the capacitive sensor unit 10 is turned off when the coil unit 20 is in sensing operation, and that the coil unit 20 is turned off when the capacitive sensor unit 10 is in sensing operation. Thus, it can be ensured that the capacitive sensor unit 10 is not active20 at the same time as the coil unit to strictly separate data transmissions by the capacitive sensor unit 10 and the coil unit 20. A virtual and/or physical switch, for example on the control unit 102, can be provided for switching between data transmission using the capacitive sensor unit 10 and data transmission using the coil unit 20.

[0071] As further shown in FIGS. 1 to 3, the winding 21 of the coil unit 20 may be substantially looped and/or circular in shape and preferably extend along an outer edge of the printed circuit board 101.

[0072] As shown in FIGS. 2 and 3, the winding 21 of the coil unit 20 lies in the plane of the printed circuit board 101 and in the plane in which the capacitive sensor unit is arranged, in particular in a planar manner.

[0073] The foregoing explanation of the embodiments describes the present invention exclusively in the context of examples. Of course, individual features of the embodiments can be freely combined with each other, provided that this is technically reasonable, without leaving the scope of the present invention.

LIST OF REFERENCE SIGNS

[0074] 100 Sensor device [0075] 101 Printed circuit board [0076] 102 Control unit [0077] 10 Sensor unit [0078] 11 First sensor element [0079] 12 Second sensor element [0080] 20 Coil unit [0081] 21 Winding [0082] 1 Electronic unit [0083] 2 Safety system [0084] 3 Mobile handheld device [0085] G1 1.sup.st geodesic [0086] G2 2.sup.nd geodesic [0087] I Isolines [0088] I Current.sub.Winder [0089] M Magnetic field line [0090] A1 Section [0091] E1 End [0092] F Vehicle [0093] T Movable part [0094] G Door handle [0095] A Recess