Electromechanical rotational damper with tension and compression stop

Abstract

A rotational damper includes a damper housing surrounding an electromagnetic damper motor and connected to a first mass via a fastening part; a coupling lever supported for pivoting relative to the damper housing and connected with a second mass; a strain wave gear mechanism for damping vibrations and including a rigid unit having an internal spline and being connected with the damper housing, and a flexible unit having an external spline and being fastened with the fastening part, wherein the first and second units are coupled with each other via the internal and external splines; a wave generator rotatably supported in the flexible unit, wherein a rotation of the wave generator causes a deformation of the flexible unit; and a wrap spring connected on one side in rotative fixed relationship with the coupling lever, and on another side connected in rotative fixed relationship with the fastening part, wherein at a predetermined pivoting of the coupling lever relative to the fastening part the wrap spring deforms the flexible unit thereby blocking the strain wave gear mechanism.

Claims

1. A rotational damper, comprising: an electromagnetic damper motor; a damper housing disposed in surrounding relationship to the electromagnetic damper motor and connected to a first mass; a coupling lever supported for pivoting relative to the damper housing and connected with a second mass; a strain wave gear mechanism configured for damping vibrations and comprising a rigid unit having an internal spline and being connected with the damper housing, and a flexible unit having an external spline coupled with the internal spline of the rigid unit; a wave generator supported in the flexible unit for rotation to thereby cause a deformation of the flexible unit; and a wrap spring connected in rotative fixed relationship with both the coupling lever and the damper housing and configured to deform the flexible unit and thereby block the strain wave gear mechanism in the presence of a predetermined pivoting of the coupling lever relative to the damper housing.

2. The rotational damper of claim 1, further comprising a housing cover rotatably supported on the damper housing and connected with the coupling lever, said wrap spring being fixed on the rigid unit via a first stop and being fixed on the housing cover via a second stop.

3. The rotational damper of claim 1, wherein the flexible unit has a gearing section arranged between the rigid unit and the wave generator, and a wall section extending axially relative to the strain wave gear mechanism, said wrap spring being arranged about the axially extending wall section.

4. The rotational damper of claim 3, further comprising a housing cover rotatably supported on the damper housing and connected with the coupling lever, said flexible unit having a radial wall section which adjoins the axially extending wall section at an end of the axially extending wall section that is distal to the gearing section, said radial wall being connected with the housing cover.

5. The rotational damper of claim 3, further comprising a bearing part securely fixed to the damper housing, said electromagnetic damper motor including a rotor rotatably supported by the bearing part, and a stator interacting with the rotor and generating a magnetic field, when energized, said stator being connected with the damper housing.

6. The rotational damper of claim 5, wherein the stator is connected with the rigid unit and the rotor is connected with the wave generator.

7. The rotational damper of claim 5, wherein the stator has a current coil arrangement which becomes energized when supplied with current, said rotor has having a magnet arrangement.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) Further advantages and applications of the present invention will become apparent from the following description in connection with the exemplary embodiments shown in the drawing.

(2) In the description, in the claims and in the drawing the terms and associated reference numerals listed in the list of reference signs below are used. In the drawing it is shown in:

(3) FIG. 1 a side view of the rotational damper according to the invention;

(4) FIG. 2 a sectional view of the rotational damper according to the invention along the line II-II in FIG. 1; and

(5) FIG. 3 a perspective view of the damper unit of the rotational damper according to the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(6) FIG. 1 shows a side view of the rotational damper 2 with a damper housing 4, which is fastened on a mass, i.e. the wheel suspension or the vehicle superstructure, via a fastening element (not shown). A coupling lever 6 is supported for pivoting relative to the housing and is connected with a second mass, i.e., the vehicle superstructure or the wheel suspension. The coupling lever 6 is connected with a housing cover 8, which is supported for rotation on the damper housing 4. Between the damper housing 4 and the housing cover 8 a strain wave gear mechanism 10 is arranged.

(7) FIG. 2 shows a section through the rotational damper along the line II-II of FIG. 1. The rotational damper 2 includes the strain wave gear mechanism which includes a rigid unit 12, which has an internal spline and is connected with the damper housing 4, and a flexible unit 14, which has an external spline and is connected with the housing cover 8, as will be described below. The two units 12, 14 of the strain wave gear mechanism are coupled with each other via a form fit for transmitting and/or converting a rotational movement between the coupling lever 6 and the damper housing 4. Inside the flexible unit 14 a wave generator 16 is supported for rotation relative to the damper housing 4, wherein when introducing a rotational force into the strain wave gear mechanism the rotation of the wave generator 16 causes a deformation of the flexible unit 14. Between the flexible unit and the wave generator 16 a rolling bearing 18 is arranged.

(8) The flexible unit 14 has a gearing section 20, which is situated between the rigid unit 12 and the flexible unit 14. Adjoining the gearing section 20 is an axial wall section 22 which is adjoined by a radial wall section 24, which is connected with the housing cover 8 via fastening elements 26, 28 for example rivets.

(9) A wrap spring 30 is wound about the axial wall section 22 of the flexible unit 14. The wrap spring 30 is connected with the coupling lever 6 via the housing cover 8 and with the fastening element (not shown) via the rigid unit 12 and the damper housing 4. For this the wrap spring 30 is on one side anchored on the rigid unit 12 via a first stop 32 and on the other side on the damper hosing 4 via a second stop 34.

(10) In this embodiment of the rotational damper 2, the wrap spring 30 is configured so that the strain wave gear mechanism 10 is blocked at a predetermined pivoting of the coupling lever 6 relative to the damper housing 4 as a result of the deformation of the flexible unit 14.

(11) As shown in FIG. 2 the housing cover 8 is supported on the rigid unit 12 or the damper housing 4 via a first rolling bearing 36. A second rolling bearing 38 is arranged between the housing cover 8 and a bearing part 40, which housing cover is in turn connected with the damper housing 4 or the mass connected with the damper housing 4.

(12) FIG. 2 also shows an electromagnetic damper motor, which has a rotor 42 with a magnet arrangement 44, which is rotatably supported on the bearing part 40 via two rolling bearings 46, 48. The damper motor has further a stator 50, which is connected with the damper housing 4 and has a coil arrangement in order to complete the damper motor.

(13) When the coupling lever 6 pivots relative to the damper housing 4 a rotational movement is introduced into the strain wave gear mechanism 10 from the housing cover 8 via the radial wall section 24, the axial wall section 22 and the flexible unit 14, wherein as a result of a pivoting the rotor 42 rotates relative to the stator corresponding to the transmission ratio of the strain wave gear mechanism 10. By supplying current to the damper motor the damping force is acts in opposition to such a pivoting.

(14) FIG. 3 shows a perspective detail view of the damper housing 4 with the wrap spring 30. Of the flexible unit 14 the radial wall section 24 and the axial wall section 22 can be seen and the rigid unit 14 with the first stop 32 for the wrap spring 30.