Active damper system

Abstract

An active damper system for damping high-frequency vibration excitation of the vehicle body, includes a damper bearing to support a vehicle chassis component on the vehicle body, wherein the damper bearing includes a first bearing element for fastening to the vehicle body and a second bearing element for fastening to the vehicle chassis component; an active actuating element connecting the first and second bearing elements; a first acceleration sensor for measuring an acceleration of the vehicle body; a control unit connected to the acceleration sensor and receiving a vertical acceleration of the vehicle body as input variable from the acceleration sensor, wherein the control unit influences the active actuation element. The active damper system includes a second acceleration sensor arranged on the second bearing element.

Claims

1. An active damper system for damping high-frequency vibration excitation of a vehicle body, comprising: a damper bearing to support a vehicle chassis component on the vehicle body, said damper bearing comprising a first bearing element for fastening to the vehicle body and a second bearing element for fastening to the vehicle chassis component, said second bearing element being coupled to the chassis component via an elastomer connection; an active actuating element connecting the first and second bearing elements; a first acceleration sensor for measuring an acceleration of the vehicle body; a second acceleration sensor arranged on the second bearing; and a control unit connected to the first and second acceleration sensors and receiving a vertical acceleration of the vehicle body as input variable from the first acceleration sensor, said control unit influencing the active actuating element.

2. The active damper system of claim 1, wherein the second bearing element is an outer ring of the damper bearing and is connected to a piston rod via an elastomer component.

3. A method for damping high-frequency vibrations into a vehicle body via a vehicle chassis component, said method comprising: providing a damper system which comprises a damper bearing to support a vehicle chassis component on the vehicle body, and an active actuating element connecting the first and second bearing elements, said damper bearing comprising a first bearing element for fastening to the vehicle body and a second bearing element for fastening to the vehicle chassis component, said second bearing element being coupled to the chassis component via an elastomer connection; measuring a vertical acceleration of the vehicle body with a first acceleration sensor; measuring a vertical acceleration of the second bearing element with a second acceleration sensor arranged on the second bearing element; and with the controller influencing the active actuating element so that the vibration is reduced by minimizing the vertical acceleration of the vehicle body, wherein the vertical acceleration of the second bearing element influences a behavior of the controller.

4. The method of claim 3, wherein the controller is constructed as PID, PI or PD-controller.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The terms and reference signs used in the below-mentioned list of reference signs are used in the description, claims and the drawing. In the drawing it is shown in:

(2) FIG. 1 a schematic view of a damping system and

(3) FIG. 2 a symbolic representation of the control structure.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(4) FIG. 1 shows a schematic view of the damper system 10. The damper system includes a damper bearing 12, which includes a first bearing element 14 and a second bearing element 16. The first bearing element 14 and the second bearing element 16 are connected by an active actuating element 18.

(5) The active actuating element 18 can be influenced by a controller unit 20, to which it is connected for that purpose.

(6) Furthermore, at least one acceleration sensor 22, 24 is provided on each of the first bearing element 14 and at the second bearing element 16, to measure the vertical acceleration of the respective bearing element.

(7) As shown in FIG. 1, the first bearing element 14 is connected to the suspension-strut dome, i.e., to the vehicle body. The acceleration sensor 22 assigned to the first bearing element 14 consequently measures the acceleration of the vehicle body in this area.

(8) The second bearing element 16 is configured as outer ring of an elastomer-bearing. The outer ring is connected to a vehicle chassis component, in the present case to a piston rod 26 of a suspension strut, via an elastomer-component 28.

(9) For regulating the acceleration of the vehicle body the acceleration sensors 22, 24 are connected with the controller unit 20.

(10) The functional principle will be further explained on the basis of the symbolical representation of the controller unit 20 in FIG. 2.

(11) FIG. 2 shows the symbolic control structure 20 of the control unit 20.

(12) The control unit 20 includes the controller 30. Input variable of the controller 30 is the deviation e(t), which results from the difference between the desired vertical acceleration of the vehicle body (d.sup.2.sup.s.sub.dome/dt.sup.2).sub.target and the acceleration of vehicle body (d.sup.2.sub.dome/dt.sup.2).sub.actual=a.sub.D measured by the acceleration sensor 22. In the present example the vehicle body acceleration corresponds to the acceleration of the suspension-strut dome.

(13) The controller 30 outputs an actuating signal s(t) to actuate the active actuating element 18. The actuating signal is outputted by taking the acceleration of the second bearing element 16, here of the outer ring, into account d.sup.2.sup.S.sub.outer ring/dt.sup.2+a.sub.A. Because the acceleration of the outer ring is taken into account as disturbance variable in the control loop 32, an extremely efficient minimization of high-frequent vibrations in the vehicle structure can be ensured.