Door handle assembly for a motor vehicle

Abstract

A vehicle door handle assembly with a sensor device for detecting an actuation is provided. A handle of the handle assembly has a section which can be gripped from behind and an outer wall that delimits an interior in which an electronic sensor device is arranged and fixed. The handle section is formed with a reduced outer wall thickness in an actuation region and has a deformability that is increased with respect to the remaining sections of the handle. The outer wall thickness is reduced solely on the outer wall face oriented towards the interior. The handle outer wall inner face oriented towards the interior is coated with a metal layer at least in the actuation region. The electronic sensor device comprises at least one inductive distance sensor which lies opposite the metal layer in the interior of the handle to detect a deformation of the opposing outer wall.

Claims

1. A vehicle door handle assembly comprising: a handle including a graspable section that is configured to be grasped, an outer wall, an interior that is delimited by the outer wall, and sensor electronics arranged inside the handle and fixed in position therein; wherein the handle includes a reduced outer wall thickness in an actuating area in the graspable section and the actuating area has an increased deformability in comparison to other sections of the handle, with the reduced outer wall thickness being embodied exclusively on a side of the outer wall facing the interior; wherein the inside of the outer wall facing the interior is covered with a metallic layer at least in the actuating area; wherein the sensor electronics have at least one inductive distance sensor arranged opposite from the metallic layer, the inductive distance sensor operable to detect a deformation of the outer wall that supports the metallic layer; and wherein the sensor electronics have an evaluation circuit that detects signals of the inductive distance sensor and as a function of these signals, determines whether an actuation has occurred and produces an output signal, the evaluation circuit permitting a continuous calibration using a sliding average as a starting value for detecting an actuation.

2. The vehicle door handle assembly according to claim 1, wherein the sensor electronics have a board on which the inductive distance sensor is embodied and the board is accommodated in a holder, the holder being mounted in stationary fashion in the interior of the handle.

3. The vehicle door handle assembly according to claim 2, wherein the board with the inductive distance sensor is cast into the holder with a casting compound.

4. The vehicle door handle assembly according to claim 1, wherein the actuating area, opposite the side of the outer wall facing the interior, includes a continuous exterior surface.

5. The vehicle door handle assembly according to claim 4, wherein the continuous exterior surface is one of convex or planar in the actuating area.

6. The vehicle door handle assembly according to claim 1, wherein the metallic layer includes one of a foil, a metallic paint, or a plurality of metal particles disposed within the actuating area.

7. The vehicle door handle assembly according to claim 1, wherein the actuating area includes an elastically-deformable material.

8. The vehicle door handle assembly according to claim 1, wherein the evaluation circuit is configured to: detect a first signal of the inductive distance sensor; detect a second signal of the inductive distance sensor; compare the first signal to the second signal; and transmit a control signal to a central control unit based on the comparison of the first signal to the second signal.

9. The vehicle door handle assembly according to claim 1, wherein a position of the actuating area is configured to move relative to other sections of the handle, and wherein a position of the inductive distance sensor is fixed relative to the other sections of the handle.

10. A vehicle door handle assembly comprising: an inner part configured to be pulled by a user, the inner part having an outer wall and an actuating area, the actuating area being moveable relative to the outer wall; a metallic layer supported by the actuating area; an inductive distance sensor fixed relative to the inner part and configured to detect a movement of the metallic layer; and wherein the inductive distance sensor is part of sensor electronics having an evaluation circuit that detects signals of the inductive distance sensor and as a function of these signals, determines whether an actuation has occurred and produces an output signal, the evaluation circuit permitting a continuous calibration using a sliding average as a starting value for detecting an actuation.

11. The vehicle door handle assembly according to claim 10, wherein the outer wall defines a first thickness in an area adjacent to the actuating area, and wherein the actuating area defines a second thickness less than the first thickness.

12. The vehicle door handle assembly according to claim 11, wherein the area adjacent to the actuating area surrounds the actuating area.

13. The vehicle door handle assembly according to claim 11, wherein the outer wall defines an inner surface and an outer surface, the inner surface facing the inductive distance sensor, the outer surface opposite the inner surface, and wherein the outer surface includes one of convex portion or a planar portion extending from the actuating area to the area adjacent to the actuating area.

14. The vehicle door handle assembly according to claim 10, wherein the actuating area includes an elastically-deformable material.

15. The vehicle door handle assembly according to claim 10, wherein the metallic layer includes one of a foil, a metallic paint, or a plurality of metal particles disposed within the actuating area.

16. The vehicle door handle assembly according to claim 10, wherein the evaluation circuit is configured to: detect a first signal of the inductive distance sensor; detect a second signal of the inductive distance sensor; compare the first signal to the second signal; and transmit a control signal to a central control unit based on the comparison of the first signal to the second signal.

17. The vehicle door handle assembly according to claim 10, further comprising a board supporting the inductive distance sensor, the board supported by a holder fixed within an interior of the handle assembly.

18. The vehicle door handle assembly according to claim 17, further comprising a casting compound, wherein the board is secured to the holder with the casting compound.

Description

(1) FIG. 1a shows a door handle assembly according to the invention according to a first exemplary embodiment. In this exemplary embodiment, a door handle is provided, with a handle composed of two shell parts, which in the assembled state form the handle of the door handle.

(2) A handle inner part 1 of the handle facing the vehicle body is covered by a handle cover part 2, which faces away from the vehicle. Fastening means 3a, 3b are provided in order to permit the vehicle door handle assembly to be fastened to the vehicle. After the handle inner part 1 and handle cover part 2 have been assembled, they form the handle with an inner cavity in which electronic components of the handle can be accommodated. FIGS. 1a and 1b clearly show that in order to actuate a door, a user of the handle grasps behind the handle and in so doing, exerts a force on the handle inner part 1 if s/he wishes to open the door.

(3) FIG. 2 shows a section approximately at the halfway point of the longitudinal span of the handle from FIGS. 1a and 1b. The sectional region is emphasized in an enlarged detail in order to afford a view of the interior. In this depiction, it is clear how the handle is formed by the handle inner part 1 and handle cover part 2, which cooperate to form the outer wall of the handle. It is also clear that the wall thickness of the handle inner part 1 is reduced in the sectionally depicted region in order to form an actuating area 4 with a reduced wall thickness. On the inside of the door handle, a holder 5 is mounted, which serves as a support for a set of sensor electronics 6. The sensor electronics 6 lie opposite from the thinned actuating area 4 and with inductive distance sensors, which are positioned on the sensor electronics 6, detect a deformation of the actuating area 4. This is possible because a metal foil is mounted on the actuating area 4; in this example, an adhesive aluminum foil is mounted on the corresponding inner region 4.

(4) Whereas FIG. 2 shows the arrangement of components in the completely assembled handle, FIG. 3a shows the assembly with the handle cover part 2 removed. This depiction clearly shows how the area 4 of the handle inner part 1 is embodied as a weakened area with a thinner wall thickness. The area 4 is covered with an adhesive aluminum foil. The holder 5 in turn has fastening sections at its ends, which can be fixed in position by associated fastening means on the handle inner part 1. The sensor electronics 6 are inserted into the holder 5. For the sake of clarity, in this example, a situation is depicted in which the electronics are not cast in place; the electronics can, however, be cast in place in order to avoid external influences on the electronics.

(5) FIG. 3b shows that the weakened area 4 is embodied with a reduced wall thickness only from the inside of the handle. The outside of the handle inner part 1 shown in FIG. 3b is embodied uniformly and with a smooth surface. This gives a user a more comfortable operating feel and prevents dirt, water, or ice from collecting or sticking in recessed areas and resulting in malfunctions. The weakening of the material is carried out only from the protected inside of the handle inner part 1.

(6) The block circuit diagram in FIG. 4 shows the connection and interaction among the components. An inductive sensor 10 is coupled to an evaluation circuit 11 on a board 12. Spaced apart from this is a control region with a thinned wall cross-section, belonging to one shell 13 of a door handle. A metallic layer 14 is positioned on the side oriented toward the sensor 10. The metallic layer 14 can be deformed together with the underlying wall 13, as indicated by the dashed depiction and the double arrow. A deformation results in a change in the signals of the inductive distance sensor 10. The evaluation circuit 11 evaluates the signals of the sensor 10 and based on this, produces a control signal that is transmitted to a central control unit 15 in the vehicle. The evaluation circuit 11 permits a continuous calibration of the system; a sliding average is used as a starting value for detecting an actuation.

(7) This makes it possible to adjust the sensitivity of the sensor 11 to changed environmental conditions such as temperature changes and expansions or contractions in length. If the inductive distance sensor 11 detects signals, which indicate that an actuation has occurred, then the evaluation circuit compares the corresponding sensor signals to the comparison values from the recent past.

(8) There are various possible signal responses for a detection of the actuation. For example, it can be necessary for the actuation to exceed a certain threshold for a predetermined period of time in order to prompt a release of the door lock by issuing a corresponding actuation signal. It is basically also possible to detect other control patterns such as a multiple actuation.