DEVICE FOR DETECTING BY INDUCTION AN INTENTION TO LOCK A MOTOR VEHICLE DOOR WITH A TARGET ON A LEVER ARM

Abstract

The invention relates to a device for detecting the intention to unlock an opening element (1) of a motor vehicle with a housing (4) containing a support element (12) having a region of contact (11) with a handle (2) and being associated with an amagnetic metal target (6), the device comprising a printed circuit board (9), a voltage source and at least one emitter primary coil (7). The support element (12) forms an elongated lever arm, the target (6) being arranged at its longitudinal free end with its other longitudinal end fixed to an anchoring point (14) on the housing (4) while being flexible toward the primary coil (7) under the action of the pressure from the user on the opening element handle (2) or frame which is transmitted to the contact region (11) located away from the target (6) by more than half of a length of the support element (12).

Claims

1. A device for detecting the intention of a user to lock or unlock an opening element (1) of a motor vehicle, the device being intended to be integrated into an opening element handle (2) or frame and consisting of a housing (4) containing a support element (12), a variation in the position of which along a predetermined axis (A) occurs under pressure from a hand (3) of the user on the opening element handle (2) or frame, the support element (12) having a region of contact (11) with the opening element handle (2) or frame and being associated with an amagnetic metal target (6), the device comprising a printed circuit board (9), a voltage source and at least one emitter primary coil (7), wherein the support element (12) forms an elongated lever arm, the target (6) being arranged at a longitudinal free end of the lever arm which has another longitudinal end fixed to an anchoring point (14) on the housing (4), the lever arm being flexible toward the primary coil (7) under the action of the pressure from the user on the opening element handle (2) or frame which is transmitted to the contact region (11), the contact region (11) being located away from the target (6) by more than half of a total length of the support element (12).

2. The detection device as claimed in claim 1, wherein the support element (12) is in the form of a flexible strip that is elastically returned to a position corresponding to no pressure from a hand (3) of a user on the opening element handle (2) or frame.

3. The detection device as claimed in claim 1, wherein the support element (12) forms a single piece with the target (6), being made of an amagnetic conductive metal material.

4. The detection device as claimed in claim 1, wherein the support element (12) and the target (6) are made of brass or bronze.

5. The detection device as claimed in claim 4, wherein the longitudinal end of the support element (12) which is fixed to an anchoring point (14) on the housing (4) is secured toward a longitudinal end (13a) of the housing (4), the support element (12) extending over more than half of a length of the housing (4).

6. The detection device as claimed in claim 5, wherein the support element (12) is borne outside the detection device on a longitudinal end (13a) of a cover (13) enclosing the housing (4), the cover (13) having an opening through which penetrates a free longitudinal end portion of the support element (12) bearing the target (6).

7. The detection device as claimed in claim 1, wherein the contact region (11) is a convex portion of the support element (12) which is turned away from the printed circuit board (9) toward the exterior of the device.

8. The detection device as claimed in claim 1, wherein the primary coil (7) is positioned on the printed circuit board (9) and faces the target (6) when the support element (12) is in the flexed position, the target (6) being borne on a face of the support element (12) that is turned toward the primary coil (7) and the printed circuit board (9).

9. The device as claimed in claim 8, further comprising at least one secondary coil (8) that receives a magnetic field induced by said at least one primary coil (7), a variation in the magnetic field and in an induced voltage received by said at least one secondary coil (8) being detected by means for measuring a parameter resulting from the induced voltage in the secondary coil (8) when pressure from a hand (3) of the user is applied to the opening element handle (2) or frame.

10. The device as claimed in claim 9, wherein said at least one primary coil (7) and secondary coil (8) are arranged in parallel respective planes, and perpendicular to a plane of the printed circuit board (9), a length of the target (6) extending perpendicular to the longitudinal free end of the support element (12), or said at least one primary coil (7) and secondary coil (8) are arranged in respective planes that are parallel to the plane of the printed circuit board (9), a length of the target (6) extending parallel to and bearing against the longitudinal free end portion of the support element (12).

11. The device as claimed in claim 1, wherein the support element (12) forms an electrode for a capacitive sensor, the device fulfilling the dual function of inductive sensor and of capacitive sensor.

12. An external handle (2) or frame of an opening element of a motor vehicle, comprising a detection device as claimed in claim 1 and at least one elastically deformable external contour region that is aligned along the predetermined axis (A) with the contact region (11).

13. A motor vehicle, comprising at least one external handle or a frame of an opening element as claimed in claim 12.

14. The detection device as claimed in claim 2, wherein the support element (12) forms a single piece with the target (6), being made of an amagnetic conductive metal material.

15. The detection device as claimed in claim 2, wherein the support element (12) and the target (6) are made of brass or bronze.

16. The detection device as claimed in claim 3, wherein the support element (12) and the target (6) are made of brass or bronze.

17. The detection device as claimed in claim 2, wherein the contact region (11) is a convex portion of the support element (12) which is turned away from the printed circuit board (9) toward the exterior of the device.

18. The detection device as claimed in claim 3, wherein the contact region (11) is a convex portion of the support element (12) which is turned away from the printed circuit board (9) toward the exterior of the device.

19. The detection device as claimed in claim 4, wherein the contact region (11) is a convex portion of the support element (12) which is turned away from the printed circuit board (9) toward the exterior of the device.

20. The detection device as claimed in claim 5, wherein the contact region (11) is a convex portion of the support element (12) which is turned away from the printed circuit board (9) toward the exterior of the device.

Description

[0037] Other features, aims and advantages of the present invention will become apparent on reading the detailed description that follows and on examining the appended drawings given by way of non-limiting examples, and in which:

[0038] FIG. 1 schematically shows a sectional view of a motor vehicle door handle with a device for detecting the intention of a user to lock or unlock a motor vehicle door, this device being in accordance with one embodiment according to the present invention comprising a flexible support element,

[0039] FIG. 2 schematically shows a sectional view of a motor vehicle door handle at the level of the device for detecting the intention of a user to lock or unlock a motor vehicle door according to one embodiment of the present invention, the device comprising a flexible support element for supporting a target that moves when a hand of a user presses against the handle,

[0040] FIG. 3 schematically shows a perspective view of an assembly of a target and its flexible support element, the target facing a printed circuit board that bears one or more coils, the target being lowered toward the printed circuit board due to the flexibility of the support element when pressure from the hand of the user on a handle or frame of an opening element is transmitted to the support element, the support element, the target and the printed circuit board forming part of a device according to the present invention.

[0041] With particular reference to FIGS. 1 and 2, the present invention relates to a device for detecting the intention of a user to lock or unlock an opening element 1 of a motor vehicle. The opening element 1 is advantageously a motor vehicle door but may also be the trunk of the motor vehicle or any other opening element of the motor vehicle.

[0042] The device is intended to be integrated into an element of the opening element 1, most frequently a handle 2 but also a frame of the opening element 1, and consists of a housing 4 containing a support element 12, a variation in the position of which along a predetermined axis A occurs under pressure from a hand 3 of the user on the opening element handle 2 or frame.

[0043] The support element 12 has a region of contact 11 with the opening element handle 2 or frame and is associated with an amagnetic metal target 6. In addition, the device comprises a printed circuit board 9, a voltage source and at least one emitter primary coil 7.

[0044] According to the invention, the support element 12 forms an elongated lever arm, the target 6 being arranged at a longitudinal free end of the lever arm which has its other longitudinal end fixed to an anchoring point 14 on the housing 4. The lever arm as a support member 12 is flexible toward the primary coil 7 under the action of the pressure from the user on the opening element handle 2 or frame which is transmitted to the contact region 11.

[0045] The contact region 11 is located away from the target 6 by more than half of a total length of the support element 12, so that pressure from the hand 3 of the user on the handle 2 or frame is transmitted to the contact region 11 and causes a more pronounced movement of the target 6 than the same pressure exerted on the target 6 would cause due to the pronounced flexion of the free end of the support element 12 bearing the target 6.

[0046] As can be seen with reference to FIG. 2, the device comprises a printed circuit board 9, a voltage source and at least one emitter primary coil 7. In FIG. 2, the primary coil 7 is shown as one turn and a secondary coil 8 is shown represented by one turn. The number of turns may of course be higher.

[0047] The invention also relates to an external handle 2 or frame of a motor vehicle opening element 1 comprising such a detection device and at least one elastically deformable external contour region that is aligned along the predetermined axis A with the contact region 11.

[0048] As can be seen in FIG. 2, a finger 3 of the user presses against the external face of an external portion of the handle 2 which is outermost with respect to the vehicle. This pressure is transmitted to the contact region 11 borne by the support element 12, advantageously close to its fixed anchoring point 14 on the housing 4, in any case closer to this fixed anchoring point 14 than to the target 6 located at the other longitudinal end of the support element 12.

[0049] This takes place along a first predetermined axis denoted by A. This pressure on the contact region 11 is transmitted to the target 6 which moves closer to the printed circuit board 9 by moving along a second predetermined axis A′ parallel to the first predetermined axis A but at a distance from this first predetermined axis A.

[0050] The invention also relates to a motor vehicle comprising at least one such opening element handle 2 or frame.

[0051] As non-essential features of the present invention, the housing 4 containing the support element 12 may rest on an internal portion 2b of the handle 2 opposite an external portion 2a of the handle 2 which is facing away from the vehicle and against the external face of which external portion 2a the finger 3 of the user is pressed.

[0052] The internal portion 2b of the handle 2 rests against the opening element 1 of the motor vehicle or is facing the opening element 1 of the motor vehicle. It is between the internal portion 2b of the handle 2 facing the opening element 1 and the external portion 2a of the handle 2 facing away from the vehicle that an empty space houses the detection device according to the present invention integrated into the housing 4.

[0053] The housing 4 may be open at its end facing the exterior of the handle 2 and covered with a cover 13, which however lets the support element 12 with its contact region 11 protrude from the housing 4. Between the cover 13 and the internal wall of the external portion 2a of the handle 2, inside the handle 2, a layer of foam 10 may be locally inserted.

[0054] With reference to all of the figures, the support element 12 may be in the form of a flexible strip that is elastically returned to a position corresponding to no pressure from a hand 3 of a user on the opening element handle 2 or frame. This is the rest position of the support element 12 for which no intention to lock is detected. It is therefore normal for the support element 12 to automatically return to this position when no pressure from a hand 3 of the user on the opening element handle 2 or frame is detected.

[0055] In one preferred embodiment of the present invention, the support element 12 forms a single piece with the target 6, being made of an amagnetic conductive metal material. The target 6 may also be welded or glued to the support element 12. The target 6 may also comprise fixing means for securing it to the support element 12.

[0056] The support element 12 and the target 6 may be made of different metal amagnetic materials, for example brass or bronze. Brass and bronze exhibit good flexibility and can be easily welded.

[0057] By way of non-limiting example, the support element 12 and the target 6 may be made of amagnetic iron with a magnetic permeability μ equal to 1. The problem arising from this specific material is that during the manufacture of the support element 12 for supporting the target 6, due to the treatments in which the constituent material of the support element 12 is wound or unwound, this support element 12 regains a magnetic permeability higher than 1. It may then be a good idea to subject it to a subsequent demagnetization treatment.

[0058] As can be seen in FIG. 2, the longitudinal end of the support element 12 which is fixed to an anchoring point 14 on the housing 4 can be secured toward a longitudinal end 13a of the housing 4, the support element 12 extending over more than half of a length of the housing 4. This longitudinal end may be a longitudinal end 13a of the cover 13 covering the housing 4.

[0059] The support element 12 may therefore be borne at least partially outside the detection device on a longitudinal end 13a of a cover 13 enclosing the housing 4. The cover 13 may have an opening through which penetrates a free longitudinal end portion of the support element 12 bearing the target 6, which takes place when the support element 12 flexes under pressure exerted on its contact region 11 located away from the target 6.

[0060] As can be seen in FIG. 3, the longitudinal end of the support element 12 may be anchored to an anchoring point 14 which is close to a longitudinal end 13 of the cover 13 but which however might not belong to the cover 13 of the housing 4 of the device. This anchoring point 14 may have a groove, not visible in the figures, into which is inserted a longitudinal end portion of the support element 12 which may be glued or welded to the anchoring point 14.

[0061] As can best be seen in FIGS. 1 and 2, the contact region 11 is a convex portion of the support element 12 which is turned away from the printed circuit board 9 toward the exterior of the device. The contact region 11 may be of convex shape with respect to the external portion 2a of the handle 2 with a highest point pointing toward the external portion 2a and through the middle of which the first predetermined axis A passes, passing through a bearing region against which bears the finger of a user on the external face of the external portion 2a of the handle 2.

[0062] It is possible for this bearing region to be recognizable from the outside of the vehicle so that the user always presses in the same place on the handle 2 in the same bearing region borne by the external face of the external portion 2a of the handle 2.

[0063] As shown in FIG. 2, the primary coil 7 may be positioned on the printed circuit board 9 facing the target 6 when the support element 12 is in the flexed position, i.e. being aligned with the target 6 on the same second predetermined axis A′ mentioned above and parallel to the first predetermined axis A. The target 6 may be borne on a face of the support element 12 that is turned toward the primary coil 7 and the printed circuit board 9, facing them, at the free end of the support element 12.

[0064] There may be several different optional arrangements of the target 6 and of the emitter primary coil 7 and of at least one receiver secondary coil 8.

[0065] In a first option, a single emitter primary coil 7 may be used, advantageously connected to a capacitor and forming with the capacitor an oscillating circuit that has its own resonant frequency. The detection device then comprises measurement means for measuring an inductance of the coil and comparison means for comparing the measured inductance with a predetermined threshold inductance value representative of passage of the target 6 under the indirect action of pressure from the finger of a user on the external portion of the opening element handle 2 or frame being transmitted to the contact region 11 and then to the support element 12 by flexing it and the target 6 along with it, in order to detect the intention of a user to lock or unlock the opening element 1 of the motor vehicle.

[0066] In a second option, the device may comprise at least one receiver secondary coil 8 receiving a magnetic field induced by said at least one primary coil 7, a variation in the induced magnetic field received by said at least one secondary coil 8 being detected by measurement means for measuring a parameter of a current induced in the secondary coil 8 when pressure from a hand 3 of the user is applied to the opening element handle 2 or frame. Several arrangements of target 6 and of primary and secondary coils are then possible.

[0067] In a first, preferred optional embodiment for positioning the primary 7 and secondary 8 coils with respect to the target 6, the one or more primary coils 7 and the one or more secondary coils 8 are arranged in parallel respective planes, and perpendicular to a plane of the printed circuit board 9, a length of the target 6 extending perpendicular to the longitudinal free end of the support element 12. This first, preferred optional embodiment is shown in FIG. 1.

[0068] In a second optional embodiment for positioning the primary 7 and secondary 8 coils with respect to the target 6, the one or more primary coils 7 and the one or more secondary coils 8 are arranged in respective planes that are parallel to the plane of the printed circuit board 9, a length of the target 6 extending parallel to and bearing against the longitudinal free end portion of the support element 12. This second optional embodiment is shown in FIG. 2.

[0069] In the first embodiment, the movement of the target 6 has a guillotine effect with respect to the printed circuit board 9. It is a longitudinal area of the target 6 which is interposed between the primary and secondary coils instead of the target 6 being brought closer to the primary 7 and secondary 8 coils. A greater variation in flux is thus obtained, the area of the target 6 influencing this variation whereas in the second embodiment, only the distance between target 6 and coils 7, 8 was taken into consideration.

[0070] In the first embodiment, when the target 6 moves, there is a variation in the area of the target 6 facing the coils 7, 8 and no longer just in the distance between the target 6 and the coils 7, 8.

[0071] In these two embodiments, there may be one or more emitter primary coils 7 and one or more receiver secondary coils 8.

[0072] The secondary coils 8 may be independent of one another and differ. For example, a first secondary coil may comprise two loops in opposite directions and of equal area generating a sine voltage signal at the output of the first secondary coil and a second secondary coil may comprise three loops including one large loop and two small loops, the two small loops being in the same direction and in the opposite direction to the large loop. The second secondary coil then generates a cosine voltage signal at the output of the second secondary coil.

[0073] The sine or cosine signals of the first and second secondary coils, respectively, may be temporally correlated by calculation means in order to precisely determine the position of the target 6 in the detection device.

[0074] In a third embodiment, the support element 12 may form an electrode for a capacitive sensor, the device fulfilling the dual function of inductive sensor and of capacitive sensor, the inductive sensor comprising at least one emitter primary coil 7 which may or may not be associated with at least one receiver secondary coil 8.

[0075] The invention relates to an exterior handle 2 or frame of an opening element of a motor vehicle comprising such a detection device and at least one elastically deformable external contour region aligned along a first predetermined axis A with the contact region 11, on the exterior face of the external portion 2a of the handle. The alignment of the target 6 with the printed circuit board 9 takes place along a second predetermined axis A′ different from the first predetermined axis A.

[0076] Lastly, the invention relates to a motor vehicle comprising at least one such opening element handle 2 or frame on at least one opening element 1 present on the motor vehicle.