Decoupling unit

Abstract

A decoupling unit (10) for a chassis actuator (2) of a motor vehicle, comprising a drive part (11) rotatable about an axis of rotation (5), an output part (12) rotatable about the axis of rotation (5) and a coupling acting between them, is characterized in that the coupling has a circumferential meander spring (13) with a plurality of alternately wound spring loops (14a, 14b), wherein the spring loops (14a, 14b) engage alternately in coupling areas (15a) of the drive part (11) and in opposite coupling areas (15b) of the output part (12) for the torsionally elastic coupling of the drive part (11) and output part (12).

Description

[0001] The invention relates to a decoupling unit according to the preamble of claim 1. In addition, the invention relates to an actuator according to the preamble of claim 11. Finally, the invention relates to an adjustable roll stabilizer for a motor vehicle according to claim 13.

[0002] In chassis technology, it is common practice to equip motor vehicles with a so-called roll stabilizer to increase vehicle stability and ride comfort. In its simplest form, this is essentially a C-shaped torsion bar spring mounted centrally opposite the vehicle body, with its outer, opposite ends each coupled to a wheel suspension. This design ensures that when the vehicle corners, the body deflects at least slightly not only on the outside (due to centrifugal force) but also on the inside (following the roll to reduce roll).

[0003] To further increase vehicle stability and driving comfort, it is also known to make such roll stabilizers actively adjustable. For this purpose, an actively adjustable roll stabilizer for a motor vehicle comprises an actuator and is divided into two stabilizer sections that can be rotated relative to each other about a rotational axis using the actuator. By rotating the stabilizer sections relative to each other (about the rotational axis), a rolling motion of the vehicle body is deliberately generated or a rolling motion of the vehicle body caused by external influences is deliberately counteracted.The actuator of such a roll stabilizer comprises as essential elements a drive motor, preferably in the form of an electric motor, a gear driveable thereby, preferably in the form of a multi-stage planetary gear, and a clutch for damping in particular torsional vibrations within the drive train formed by the drive motor, the gear and the stabilizer section in driving connection therewith.

[0004] Decoupling units according to the preamble of patent claim 1 are known from DE 10 2020 209 788 A1 and DE 10 2021 201 025 B4. Both are based on a structural design according to which a star-shaped inner profile is formed on the drive part and a star-shaped outer profile on the output part. When inserted into one another, an elastomer body with a star-shaped contour acts between the drive part and output part to dampen torsional vibrations. In practice, it has been shown that such elastomer bodies are complex to manufacture due to their complex geometry. Furthermore, due to their material properties, they have the disadvantage of being sensitive to temperature. In concrete terms, this means that the decoupling behavior, such as the damping effect and deformation behavior, changes depending on the temperature.This makes it more difficult, among other things, to control an adjustable roll stabilizer equipped with it, particularly with regard to positioning (attitude control).

[0005] It is an object of the present invention to provide a decoupling unit that is easier to manufacture and less susceptible to temperature changes. Furthermore, an actuator for an adjustable roll stabilizer and an adjustable roll stabilizer for a motor vehicle are to be provided, which achieve corresponding advantages.

[0006] The stated object is initially achieved by a decoupling unit according to the features of claim 1. This is a decoupling unit for a chassis actuator of a motor vehicle, with a drive part rotatable about a rotational axis, an output part rotatable about the rotational axis, and a coupling acting therebetween. According to the invention, the decoupling unit is characterized in that the coupling has a circumferential meandering spring with a plurality of alternately wound spring loops, wherein the spring loops alternately engage in coupling regions of the drive part and in opposite coupling regions of the output part for the torsionally elastic coupling of the drive part and output part. The meandering spring is expediently an elastically deformable component with a meandering course circumferentially around the rotational axis with respect to the axis of rotation.The meander spring forms alternatingly wound spring loops that alternately engage the coupling areas of the drive part and the opposite coupling areas of the output part. The drive part and output part are thus torsionally elastically coupled. This creates a decoupling unit that is particularly suitable for damping torsional vibrations between the drive part and output part.

[0007] Advantageously, the decoupling unit is designed such that the coupling areas establish a mechanical coupling, particularly achieved through positive engagement, between the meander spring and the drive part, as well as between the meander spring and the output part, to enable a distributed force transmission over the circumference. Accordingly, force transmission takes place at a plurality of coupling areas distributed over the circumference, resulting in a torque transmission between the drive part and the output part relative to the rotational axis.

[0008] According to a preferred embodiment, the coupling regions are formed so that their ends face each other on the drive part and on the output part.

[0009] Advantageously, the coupling regions provided on the drive part and the output part are designed to complement the head sections of the meander spring, so that a head section of the associated spring loop extends axially into them to create a positive coupling. The coupling regions can be designed differently for this purpose; in particular, they could be pocket-shaped in different ways to accommodate a head section of the associated meander spring. Other designs of the coupling regions are also conceivable to create a coupling between the meander spring and the drive part or output part.

[0010] A preferred embodiment of the decoupling unit provides for the meander spring to be designed as a ring, in particular as a circumferentially closed or circumferentially open ring. A circumferentially closed ring design offers the advantages of simple and secure assembly and consistent action across the entire circumference.

[0011] Since the meander spring is preferably designed as a single piece, it can be manufactured and assembled with minimal effort. The meander spring is preferably made of a metallic material, in particular spring steel.

[0012] An advantageous design of the decoupling element provides that the spring loops of the meander spring essentially run on an imaginary cylinder surface.

[0013] The spring loops can be designed in a variety of ways. Easier manufacturing and assembly is achieved by having a square coil on the head side and / or a round coil on the head side.

[0014] According to a preferred development of the decoupling unit, it can be provided that a spring loop has two longitudinal regions which extend substantially parallel to the axis of rotation and a transverse region which extends substantially in the circumferential direction.

[0015] Preferably, in an unloaded, undeformed state of the decoupling unit, the longitudinal regions of the spring loops are aligned parallel to the rotation axis, while in a loaded, deformed state of the decoupling unit, the longitudinal regions of the spring loops are twisted relative to the rotation axis.

[0016] The object mentioned at the outset is also achieved by an actuator for an actively adjustable roll stabilizer of a motor vehicle according to the features of claim 11. According to the invention, this has a drive train which is suitable for rotating a stabilizer section which can be connected to the actuator for the purpose of influencing the roll behavior of the motor vehicle about a rotational axis, wherein the drive train has a decoupling unit with a drive part which can be rotated about the rotational axis, an output part which can be rotated about the rotational axis and a clutch acting therebetween.According to the invention, the actuator is characterized in that the coupling comprises a circumferential meander spring with a plurality of alternately wound spring loops, wherein the spring loops alternately engage in coupling areas of the drive part and in opposite coupling areas of the output part for the torsionally elastic coupling of the drive part and the output part. Regarding the design of the decoupling unit used in the actuator according to the invention, reference is made to the previous relevant explanations, which are also applicable to the actuator.

[0017] According to a preferred development of the actuator, its drive train has a drive unit which comprises a drive motor and a gear driveable thereby, in particular in the form of a multi-stage planetary gear, which reduces a motor speed provided by the drive motor into a relatively lower gear output speed with which the drive part of the decoupling unit can be driven.

[0018] The object mentioned at the outset is further achieved by an adjustable roll stabilizer for a motor vehicle according to the features of claim 13. This comprises a first stabilizer section which can be coupled to a first wheel suspension and a second stabilizer section which can be coupled to a second wheel suspension, wherein the first stabilizer section and the second stabilizer section can be rotated relative to one another about the axis of rotation by means of an actuator of the type described above acting therebetween in order to influence a roll behavior of the motor vehicle.

[0019] The invention is explained in more detail below with reference to the accompanying drawings. Further advantageous effects of the invention are also apparent from these drawings. The drawing shows: Fig. 1 an actively adjustable roll stabilizer in a simplified schematic view, Fig. 2 a decoupling unit according to the invention in a simplified perspective view obliquely from above.

[0020] Fig. 1 shows a schematic view of an actively adjustable roll stabilizer 1 for a motor vehicle. The adjustable roll stabilizer 1 can be installed in a manner not shown in detail here in the area of ​​the front axle and / or in the area of ​​the rear axle on the vehicle body (body) of a motor vehicle to be equipped with it. The essential elements of the adjustable roll stabilizer comprise a first stabilizer section 3a and a second stabilizer section 3b, which can be rotated relative to one another about a rotation axis 5 by means of an actuator 2 arranged therebetween. In a manner known per se, the first stabilizer section 3a is coupled at its end facing away from the actuator 2 to a simplified first wheel suspension 9a, which rotatably supports a first wheel 4a.Likewise, the second stabilizer section 3b is coupled at its end facing away from the actuator 2 to a second wheel suspension 9b, which rotatably receives a second wheel 4b.

[0021] The wheel suspensions 9a and 9b fundamentally enable independent vertical movements of the wheels 4a and 4b in a vehicle vertical direction z, for example, to compensate for uneven road surfaces when the motor vehicle is moving. However, the wheel suspensions 9a and 9b of the wheels 4a and 4b are coupled to one another via the actively adjustable roll stabilizer 1. The C-shaped arrangement formed by the first stabilizer section 3a, the actuator 2, and the second stabilizer section 3b serves, in a manner known per se, to couple the lifting movements of the wheels 4a and 4b (copying behavior). In addition, the actuator 2 can be used to actively cause a relative rotation of the stabilizer sections 3a and 3b to one another, thus influencing the rolling behavior of the motor vehicle.

[0022] The actuator 2, shown here in simplified form as a cylindrical body, comprises as essential elements a drive motor 7, preferably designed as an electric motor, a gear 8, preferably designed as a multi-stage planetary gear, and a decoupling unit 10. The drive motor 7, the gear 8 and the decoupling unit 10 are arranged coaxially with respect to the rotation axis 5 and are located within a housing 6 of the actuator 2.

[0023] Accordingly, the actuator 2 has a drive train, comprising a drive unit formed by the drive motor 7 and the gear 8 driven thereby, which reduces a motor speed provided by the drive motor 7 into a relatively lower gear output speed, with which a Fig. 2, the drive part 11 of the decoupling unit 10 is drivable. The drive train of the actuator 2 is suitable for rotating the stabilizer section 3b, which can be connected to the actuator 2, about the rotation axis 5 for the purpose of influencing the rolling behavior of the motor vehicle equipped therewith. Fig. 2, the drive train of the actuator 2 comprises the decoupling unit 10.

[0024] Fig. 2 shows a simplified perspective view of a decoupling unit 10 according to the invention. This can advantageously be attached to an adjustable roll stabilizer 1 or an actuator 2 as shown in FIG. Fig. 1. For orientation, Fig. 2 the rotation axis 5 is drawn, which, like the rotation axis 5 according to Fig. 1 in order to determine their possible placement and orientation at the installation location within an actuator 2, as shown in Fig. 1. Accordingly, in Fig. 2, in addition to the rotation axis 5, the position of the gear 8 and the position of the second stabilizer section 3b on axially opposite sides of the decoupling unit 10 are indicated by reference numerals.

[0025] According to the presentation of the Fig. 2, the decoupling unit 10 according to the invention comprises as essential elements a drive part 11, a driven part 12 and a meander spring 13 acting therebetween. The representation of the Fig. 2 is schematically simplified, but the functional principle according to the invention can be explained using it.

[0026] Both the drive part 11 and the driven part 12 are rotatable about the rotation axis 5. When installed in an actuator 2, as shown in Fig. 1, the drive part 11 is connected in a rotationally fixed manner to an output of the gear 8. Accordingly, the drive part 11 of the decoupling unit 10 - when installed in an actuator 2 - can be driven via the drive unit (formed by the drive motor 7 and the gear 8 driven by it). The output part 12, in turn, is installed within an actuator 2, as shown in FIG. Fig. 1 is connected or connectable in a rotationally fixed manner to a second stabilizer section 3b.

[0027] The decoupling unit 10 according to Fig. 2 is characterized by a coupling acting between the drive part 11 and the output part 12. This coupling has, as an essential element, a circumferential meander spring 13, which is made in one piece from an elastic material, preferably from a metallic material such as spring steel. The meander spring 13 forms a plurality of alternately wound spring loops 14a and 14b. For the torsionally elastic coupling of the drive part 11 and the output part 12, the spring loops 14a and 14b alternately engage in coupling areas 15a of the drive part 11 and in opposite coupling areas 15b of the output part 12. The coupling areas 15a and 15b establish a mechanical coupling, achieved by form-fitting, between the meander spring 13 and the drive part 11, as well as between the meander spring 13 and the driven part 12, in order to enable a force transmission distributed over the circumference.Accordingly, a drive torque M1 applied to the drive part 11 can be transmitted at least partially to the output part 12 via the coupling formed in this way (usable output torque M2).

[0028] Conveniently, the coupling regions 15a are formed on the front side of the drive part 11, while the coupling regions 15b are formed on the front side of the output part 12.

[0029] To ensure effective power transmission, the coupling regions 15a and 15b provided on the drive part 11 and the driven part 12 are preferably designed to complement the head sections 16a and 16b of the meander spring 13, so that a head section 16a, 16b of the associated spring loop 14a, 14b extends axially into the latter to form a positive coupling. A detailed design of the coupling regions 15a and 15b can be found in the Fig. 2. Various configurations of the coupling regions are conceivable. According to a preferred design, the coupling regions 15a and 15b are, for example, pocket-shaped. Alternatively, another structure complementary to the head sections 16a and 16b, respectively, could be formed on the drive part 11 or the drive part 12, enabling force transmission.

[0030] According to the presentation in Fig. 2, the meander spring 13 is a circumferentially closed ring, particularly a one-piece component. To assemble the decoupling unit 10, the drive part 11, the meander spring 13, and the driven part 12 can be connected, for example, plugged together, parallel to a joining direction 17.

[0031] The spring loops 14a, 14b of the meander spring 13 extend along an imaginary cylindrical surface. According to the illustrated design, the spring loops 14a, 14b each have a square coil at the head end. Alternatively or additionally, it is conceivable for the spring loops to have round coils at the head end.

[0032] Each of the spring loops 14a and 14b has two longitudinal regions extending substantially parallel to the rotation axis 5 and a transverse region extending substantially in the circumferential direction. In a Fig. In the unloaded, undeformed state of the decoupling unit 10 shown in Figure 2, the longitudinal regions of the spring loops 14a and 14b are aligned parallel to the rotation axis. However, when the decoupling unit 10 is loaded, particularly when a torque is transmitted between the drive part 11 and the driven part 12, the longitudinal regions of the spring loops 14a and 14b are twisted relative to the rotation axis 5.

[0033] Advantageously for the described application, the decoupling unit 10 with the coupling formed by the circumferential meander spring 13 is easy to manufacture and assemble. Since the meander spring 13 can be made of a metallic material, for example, spring steel, the decoupling unit 10 according to the invention can advantageously achieve a damping effect that is less sensitive to temperature changes compared to previously known decoupling units. The aforementioned advantages have a corresponding effect on the actuator according to the invention and an adjustable roll stabilizer equipped therewith. Reference symbol 1 adjustable roll stabilizer 2 actuators 3a; 3b first stabilizer section; second stabilizer section 4a; 4b first wheel; second wheel 5 Rotation axis 6 housings 7 Drive motor 8 (multi-stage planetary) gear 9a; 9b first wheel suspension; second wheel suspension 10 Decoupling unit 11 Drive part 12 Stripping section 13 meander feather 14a; 14b Spring loop (drive side; output side) 15a; 15b Coupling area (drive; output) 16a; 16b Head section (of the spring loop) 17 Joining direction M1 drive torque M2 output torque x Vehicle longitudinal direction y vehicle transverse direction z Vehicle vertical direction QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2020 209 788 A1

[0004] DE 10 2021 201 025 B4

[0004]

Claims

[1] Decoupling unit (10) for a chassis actuator (2) of a motor vehicle, with a drive part (11) rotatable about a rotational axis (5), an output part (12) rotatable about the rotational axis (5) and a coupling acting therebetween, characterized by that the coupling has a circumferential meander spring (13) with a plurality of alternately wound spring loops (14a, 14b), wherein the spring loops (14a, 14b) engage alternately in coupling regions (15a) of the drive part (11) and in opposite coupling regions (15b) of the output part (12) for the torsionally elastic coupling of the drive part (11) and the output part (12). [2] Decoupling unit (10) according to claim 1, characterized bythat the coupling regions (15a, 15b) produce a mechanical coupling, in particular achieved by positive locking, between the meander spring (13) and the drive part (11), as well as between the meander spring (13) and the driven part (12), in order to enable a force transmission distributed over the circumference. [3] Decoupling unit (10) according to claim 1 or 2, characterized by that the coupling regions (15a, 15b) are each formed on the drive part (11) and on the output part (12) facing each other at the end. [4] Decoupling unit (10) according to one of the preceding claims, characterized by that the coupling regions (15a, 15b) provided on the drive part (11) and on the output part (12) are designed to be complementary to head sections (16a, 16b) of the meander spring (13), so that a head section (16a, 16b) of the associated spring loop (14a, 14b) dips into the latter in the axial direction in order to produce a positive-locking coupling. [5] Decoupling unit (10) according to one of the preceding claims, characterized by that the meander spring (13) is designed as a ring, in particular as a circumferentially closed or as a circumferentially open ring. [6] Decoupling unit (10) according to one of the preceding claims, characterized by that the meander spring (13) is made in one piece. [7] Decoupling unit (10) according to one of the preceding claims, characterized by that the spring loops (14a, 14b) of the meander spring (13) run on an imaginary cylinder jacket. [8] Decoupling unit (10) according to one of the preceding claims, characterized by that the spring loops (14a, 14b) each have a square and / or round winding on the head side. [9] Decoupling unit (10) according to one of the preceding claims, characterized bythat a spring loop (14a, 14b) has two longitudinal regions which extend substantially parallel to the axis of rotation (5) and a transverse region which extends substantially in the circumferential direction. [10] Decoupling unit (10) according to claim 9, characterized by in an unloaded, undeformed state of the decoupling unit (10), the longitudinal regions of the spring loops (14a, 14b) are aligned parallel to the rotation axis (5), while in a loaded, deformed state of the decoupling unit (10), the longitudinal regions of the spring loops (14a, 14b) are twisted relative to the rotation axis (5). [11] Actuator (2) for an actively adjustable roll stabilizer (1) of a motor vehicle, comprising a drive train which is suitable for rotating a stabilizer section (3b) connectable to the actuator (2) about a rotational axis (5) for the purpose of influencing the rolling behavior of the motor vehicle, wherein the drive train has a decoupling unit (10) with a drive part (11) rotatable about the rotational axis (5), an output part (12) rotatable about the rotational axis (5) and a clutch acting therebetween, characterized by that the coupling has a circumferential meander spring (13) with a plurality of alternately wound spring loops (14a, 14b), wherein the spring loops (14a, 14b) engage alternately in coupling regions (15a) of the drive part (11) and in opposite coupling regions (15b) of the output part (12) for the torsionally elastic coupling of the drive part (11) and the output part (12). [12] Actuator (2) according to claim 11, characterized by that the drive train has a drive unit which comprises a drive motor (7) and a transmission (8) which can be driven thereby, in particular in the form of a multi-stage planetary transmission, which reduces an engine speed provided by the drive motor (7) into a relatively lower transmission output speed with which the drive part (11) of the decoupling unit (10) can be driven. [13] Adjustable roll stabilizer (1) for a motor vehicle, comprising a first stabilizer section (3a) which can be coupled to a first wheel suspension (9a) and a second stabilizer section (3b) which can be coupled to a second wheel suspension (9b), wherein the first stabilizer section (3a) and the second stabilizer section (3b) can be rotated relative to one another about the rotation axis (5) by means of an actuator (2) acting therebetween according to claim 11 or 12 in order to influence a roll behavior of the motor vehicle.

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