Deformation element arrangement and motor vehicle having a deformation element arrangement

Abstract

A deformation element arrangement is provided for a motor vehicle, having a deformation element and a vibration-generating device. The vibration-generating device is arranged and designed in such a way that the deformation element, when required, can be set in vibration so that a deformation behavior and/or a flow behavior of the deformation element is/can be varied in accordance with a request condition.

Claims

1. A deformation element arrangement for a motor vehicle, comprising: a deformation element, and a vibration-generating device coupled with the deformation element, wherein the vibration-generating device is arranged and constructed such that, when required, the deformation element is set in vibration so that a deformation behavior and/or a flow behavior of the deformation element is varied in accordance with a requirement condition, the deformation element comprises an elastic shell filled with a thixotropic material or a rheopectic material.

2. The deformation element arrangement according to claim 1, wherein the deformation element is mountable on the motor vehicle and is constructed such that, in an event of a collision of the motor vehicle with a pedestrian, the deformation element dampens an impact of the pedestrian onto the motor vehicle.

3. The deformation element arrangement according to claim 2, wherein the deformation element is adapted for being arranged on a forward vehicle end and/or on a rearward vehicle end.

4. The deformation element arrangement according to claim 3, wherein the deformation element is adapted to be arranged on a bumper cross member.

5. The deformation element arrangement according to claim 3, wherein the deformation element is adapted to be arranged between a bumper covering and a bumper cross member.

6. The deformation element arrangement according to claim 5, wherein the deformation element extends essentially over an entire width of the bumper cross member.

7. The deformation element arrangement according to claim 4, wherein the deformation element extends essentially over an entire width of the bumper cross member.

8. The deformation element arrangement according to one of claim 1, comprising: a control unit which is adapted for controlling the vibration-generating device as a function of a vehicle speed.

9. The deformation element arrangement according to claim 8, wherein the control unit is further adapted for controlling or regulating the vibration-generating device as a function of a detection of an imminent collision of the motor vehicle with an object or a pedestrian.

10. The deformation element arrangement according to claim 1, further comprising: a control unit which is adapted for controlling or regulating the vibration-generating device as a function of a detection of an imminent collision of the motor vehicle with an object or a pedestrian.

11. The deformation element arrangement according to claim 8, wherein the control unit activates the vibration-generating device within a speed range of the motor vehicle that is relevant to a pedestrian protection, and thereby increases a deformability and/or a flowability of the deformation element within this speed range.

12. The deformation element according to claim 11, wherein the speed range is between 20 km/h and 50 km/h.

13. The deformation element arrangement according to claim 9, wherein the control unit activates the vibration-generating device when detecting the imminent collision of the motor vehicle with the pedestrian and thereby increases a deformability and/or flowability of the deformation element.

14. The deformation element arrangement according to claim 10, wherein the control unit activates the vibration-generating device when detecting the imminent collision of the motor vehicle with the pedestrian and thereby increases a deformability and/or flowability of the deformation element.

15. The deformation element arrangement according to claim 1, wherein the vibration-generating device is adapted for generating vibrations in an ultrasonic range by way of at least one piezo actuator.

16. The deformation element arrangement according to claim 1, wherein the deformation element has at least one opening, through which the thixotropic material or the rheopectic material is displaceable as a result of an effect of force.

17. The deformation element arrangement according to claim 1, wherein: the thixotropic material or the rheopectic material, in a first operating state of the vibration-generating device, is highly viscous or predominantly has properties of a solid material, and the thixotropic material or the rheopective material, in a second operating state of the vibration-generating device, has low viscosity or predominantly has properties of a fluid.

18. A motor vehicle having a deformation element arrangement according to claim 1.

19. A deformation element arrangement for a motor vehicle, comprising: a deformation element, and a vibration-generating device coupled with the deformation element, wherein the vibration-generating device is arranged and constructed such that, when required, the deformation element is set in vibration so that a deformation behavior and/or a flow behavior of the deformation element is varied in accordance with a requirement condition, and the vibration-generating device is adapted for utilizing natural vibrations of the motor vehicle in order to set the deformation element in vibration.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic sectional lateral view of a deformation element arrangement according to an embodiment of the present invention.

(2) FIG. 2 is a schematic sectional lateral view of a deformation element arrangement according to an embodiment of the present invention during a collision.

DETAILED DESCRIPTION OF THE DRAWINGS

(3) In the following, an embodiment of the present invention will be described in reference to FIGS. 1 and 2.

(4) FIG. 1 is a schematic sectional lateral view of a deformation element arrangement 1. In particular, the deformation element arrangement consists of a deformation element 3, which is arranged on a bumper cross member 5. The deformation element 3 is arranged between a bumper covering 20 and the bumper cross member 5. The bumper cross member 5, in turn, is mounted on two forward side-members 15, only one side member 15 being visible in the lateral view of the figures.

(5) The deformation element 3 consists of an elastic shell 9 and a thixotropic material 7 which is accommodated inside the shell 9. The shell 9 is impermeable for the thixotropic material 7.

(6) In a normal state, in which it is exposed to no target-oriented vibrations, the thixotropic material is essentially in a high-viscosity or solid state or in a solid-like state.

(7) The deformation element arrangement 1 further has a vibration-generating device 30 which is arranged and constructed such that it can set the deformation element and particularly the thixotropic material 7 in vibration. The vibration-generating device preferably consists of several ultrasonic piezo actuators, which are arranged on the bumper cross member in contact with the deformation element 3 or the thixotropic material 7.

(8) The deformation element arrangement 1 further has a control unit 40 (shown schematically), which controls the vibration generating device 30. Controlled by the control unit, the vibration generating device 30 sets the deformation element 3 in vibration, when a requirement condition has been met such that the thixotropic material 7 predominantly has the properties of a fluid or acts like a fluid. As a result, the deformation element 3 can be slightly deformed when it impacts on an obstacle.

(9) The control unit activates especially the vibration-generating device in cases in which a protection of pedestrians is required who collide with the motor vehicle by way of the bumper. For this purpose, it is necessary that the deformation element 3 can easily be deformed within a defined speed range which, for example, is a range of approximately 20 km/h to approximately 50 km/h, and will therefore be soft.

(10) Correspondingly, the control unit controls the vibration-generating device such that the deformation element 3 will be set in vibration only when the vehicle is moving within the above-mentioned speed range. The requirement condition is therefore the above-mentioned speed range.

(11) According to a modification of the embodiment, it is further contemplated that the control unit would switch on the vibration-generating device as an additional requirement condition only if an imminent collision with a pedestrian is detected by way of a suitable sensor system.

(12) In cases in which the vehicle travels more slowly than 20 km/h or more rapidly than 50 km/h, the vibration-generating device will not be activated, so that the deformation element 3 will be comparatively hard in order to better be able to contribute to the absorption of collision energy for the protection of a vehicle occupant. In this case, the thixotropic material 7 will be in a high-viscosity, solid or solid-like state.

(13) FIG. 2 illustrates a collision with a pedestrian 100 who impacts on the deformation element 3, in which case, the thixotropic material 7 had previously been changed by the vibration generating device to a low-viscosity, fluid-like state, so that it can be easily deformed and is therefore softer. In addition, an opening 11 is provided in the shell 9 and the bumper cross member 5, through which opening 11 the thixotropic material can flow out of the shell 9 in the low-viscosity state, so that the deformation element 3 behaves even more softly during the collision, i.e. a deformability of the deformation element 3 is even greater. Behind the opening 11, on a rearward side of the bumper cross member 5 facing away from the deformation element 3, an elastic reservoir 13 is provided, in which the outflowing thixotropic material 7 can be caught.

(14) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.