Decoupling unit

Abstract

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, wherein the coupling has a spring-damper unit acting between the drive part (11) and the output part (12), comprising at least one spring element (13) which torsionally couples the drive part (11) to the output part (12) and is provided with a metal mesh (18) for damping torsional vibrations, characterized in that the at least one spring element is a coil spring (13) with a plurality of coils extending around the axis of rotation (5), wherein a first end (14) of the coil spring (13) is connected to the drive part (11) and a second end (15) of the coil spring (13) is connected to the output part (12).to transmit torque between the drive part (11) and the output part (12).

Description

[0001] The invention relates to a decoupling unit for a chassis actuator of a motor vehicle according to the preamble of claim 1. Furthermore, the invention relates to an actuator for an actively adjustable roll stabilizer of a motor vehicle according to the preamble of claim 12. Furthermore, the invention relates to an adjustable roll stabilizer for a motor vehicle according to claim 13.

[0002] In chassis engineering, 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 in the middle relative to the vehicle body, with its outer, opposing ends each connected to a wheel suspension. This design ensures that when the vehicle corners, the roll stabilizer not only compresses on the outside of the curve (due to centrifugal force) but also, at least to some extent, on the inside (a copying effect to reduce body roll).

[0003] To further enhance vehicle stability and ride comfort, it is also known to design such roll stabilizers to be actively adjustable. 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 around a rotational axis by means of the actuator. By rotating the stabilizer sections relative to each other (around the rotational axis), a roll movement of the vehicle body is either deliberately generated or a roll movement 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 gearbox driven by it, preferably in the form of a multi-stage planetary gearbox, and a coupling for damping, in particular, torsional vibrations within the drive train formed from the drive motor, gearbox and thus the stabilizer section connected to the drive.

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

[0005] From DE 10 2019 101 368 A1, a decoupling unit for a chassis actuator of a motor vehicle is known according to the features of the preamble of claim 1, in which the drive part and the driven part for torque transmission are understood to have a star-like interlocking structure of outwardly and inwardly projecting webs, respectively. A damping element formed from pressed wire mesh for damping road surface irregularities is arranged spatially between them. Due to the complex geometry of the star-like interlocking structure and the large number of individual damping elements used, the previously known decoupling unit is complex to manufacture and assemble.

[0006] It is an object of the present invention to provide a decoupling unit that is easier to manufacture and exhibits low temperature sensitivity. Furthermore, an actuator for an adjustable roll stabilizer and an adjustable roll stabilizer for a motor vehicle are to be provided, both of which achieve corresponding advantages.

[0007] The aforementioned problem is initially solved by a decoupling unit according to the features of claim 1. This is a decoupling unit for a chassis actuator of a motor vehicle, comprising a drive part rotatable about an axis of rotation, an output part rotatable about the axis of rotation, and a coupling acting between them. According to the invention, the coupling has a spring-damper unit acting between the drive part and the output part, comprising at least one spring element which couples the drive part to the output part in a torsionally elastic manner and is provided with a metal mesh for damping torsional vibrations.

[0008] It was initially recognized that decoupling units known from the prior art for the aforementioned application have the disadvantage that their coupling is subject to a strong temperature dependence, meaning that the decoupling unit, or an actuator equipped with it, exhibits a significantly temperature-dependent damping characteristic. If the resulting inaccuracies in control during operation are to be avoided, a complex calibration of the actuator equipped with the decoupling unit is necessary. According to the invention, an alternative coupling design was found to remedy this. Accordingly, the coupling has a spring-damper unit that is arranged to act between the drive part and the driven part, wherein the at least one spring element of the spring-damper unit couples the drive part to the driven part in a torsionally elastic manner.By additionally providing at least one spring element with a metal mesh, damping of torsional vibrations is advantageously achieved. The metal mesh thus serves to dampen movements of the at least one spring element, particularly those caused by relative rotational movements of the output part with respect to the input part. Various embodiments are conceivable.

[0009] Advantageously, the spring-damper unit, comprising essentially the at least one spring element provided with the metal mesh, is connected on the drive side to the drive part and on the output side to the driven part. The at least one spring element and the metal mesh can be designed in various ways.

[0010] According to the invention, the at least one spring element is a spiral spring with a plurality of coils extending around the axis of rotation, wherein a first end of the spiral spring is connected to the drive part and a second end of the spiral spring is connected to the driven part in order to transmit a torque between the drive part and the driven part. Accordingly, the spring element is a machine element that establishes a torsionally elastic coupling between the drive part and the driven part and is suitable for torque transmission.

[0011] According to an advantageous embodiment, the spring-damper unit can also comprise two spring elements, each in the form of a coil spring, instead of a single coil spring. In this case, the two coil springs are advantageously arranged with opposite winding directions, acting between the drive and driven parts. The arrangement of two coil springs with opposite windings results in a symmetrical effect of the spring-damper unit, independent of the direction of rotation, since one coil spring winds up and another unwinds in each direction of rotation.

[0012] Advantageously, at least one spring element has a radial geometry comprising several radial sections, wherein a radial section has the shape of a circular arc, an involute, a line segment, a sigmoid, a sinusoid or a mixture thereof.

[0013] The drive and output sections can be designed in different ways. According to a preferred embodiment of the decoupling unit, the drive and output sections are designed to be pluggable into each other in certain areas.

[0014] The design and arrangement of the at least one spring element can be implemented in various ways. A preferred embodiment of the decoupling unit provides that the at least one spring element is configured as an inner or outer circumferential element relative to the drive part. For this purpose, the drive part and / or the output part can have an opening, for example, being partially hollow, so that the drive part can be partially inserted into the output part, with the at least one spring element also being arranged within the resulting cavity to protect it from contamination by the external environment.

[0015] Preferably, the at least one spring element has an axial geometry comprising several axial sections, wherein an axial section has the shape of a circular arc, an involute, a line segment, a sigmoid, a sinuoid or a mixture thereof.

[0016] To achieve the damping effect according to the invention, the metal mesh is advantageously formed from a fabric made of a metallic material. The metal mesh is expediently arranged on or connected to the at least one spring element in such a way that a deformation of the at least one spring element forces a deformation of the metal mesh. Due to its composition (metal mesh), the metal mesh opposes this deformation, which is also a movement, with resistance (damping force), which imparts a damping effect to the spring-damper unit.

[0017] A preferred further development provides that the metal knitting surrounds the at least one spring element in certain areas, in particular by forming the metal knitting as a tube that accommodates the spring element.

[0018] Alternatively or additionally, it can be provided that the metal knitting is formed flat and rests against at least one spring element, in particular is attached to it, for example by gluing it.

[0019] In particular, when the at least one spring element is designed in the form of a spiral spring, an advantageous embodiment of the decoupling unit provides that the metal knitting is inserted into the at least one spring element designed as a spiral spring, in particular into its windings.

[0020] The aforementioned problem is further solved by an actuator according to the features of claim 12. This actuator is for an adjustable roll stabilizer of a motor vehicle, comprising a drive train suitable for rotating a stabilizer section connectable to the actuator about an axis of rotation for the purpose of influencing the roll behavior of the motor vehicle. The drive train includes a decoupling unit with a drive element rotatable about the axis of rotation, a driven element rotatable about the axis of rotation, and a coupling acting between them. The actuator's coupling includes a spring-damper unit acting between the drive element and the driven element, comprising at least one spring element which couples the drive element to the driven element in a torsionally elastic manner and is provided with a metal mesh for damping torsional vibrations.According to the invention, the actuator is characterized in that the at least one spring element is a spiral spring with a plurality of coils extending around the axis of rotation, wherein a first end of the spiral spring is connected to the drive part and a second end of the spiral spring is connected to the output part in order to transmit a torque between the drive part and the output part. For the effects and advantages achievable with the actuator according to the invention, reference is made to the preceding descriptions concerning the decoupling unit according to the invention, which apply equally to the actuator.

[0021] The aforementioned problem is further solved by an adjustable roll stabilizer for a motor vehicle according to the features of claim 13. This comprises a first stabilizer section that can be coupled to a first wheel suspension and a second stabilizer section that can be coupled to a second wheel suspension, wherein the first stabilizer section and the second stabilizer section can be rotated relative to each other about the axis of rotation by means of an actuator of the type described above acting between them in order to influence the roll behavior of the motor vehicle.

[0022] The invention is explained and described in more detail below with reference to the accompanying drawing. Further advantageous effects of the invention also become apparent from this. The drawing shows: Fig. 1. An actively adjustable roll stabilizer in a simplified schematic representation from a slant above, Fig. 2 a decoupling unit for an actuator of a as in Fig. 1. Adjustable roll stabilizer shown in simplified exploded view from a top angle, Fig. 3 A simplified representation of a spring-damper unit, which is basically based on a system like the one in Fig. The decoupling unit shown in section 2 can be used.

[0023] Fig. Figure 1 shows a schematic view of an actively adjustable roll stabilizer 1 for a motor vehicle. The adjustable roll stabilizer 1 can be mounted to the vehicle body (chassis) of a motor vehicle in the area of ​​the front axle and / or the rear axle in a manner not shown in detail here. The adjustable roll stabilizer comprises, as essential elements, a first stabilizer section 3a and a second stabilizer section 3b, which can be rotated relative to each other about a rotational axis 5 by means of an actuator 2 arranged between them. 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 representation of a first wheel suspension 9a, which rotatably accommodates 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 accommodates a second wheel 4b.

[0024] The wheel suspensions 9a and 9b allow independent vertical movements of the wheels 4a and 4b in a vertical direction z of the vehicle, for example, to compensate for uneven road surfaces while the vehicle is in motion. However, the wheel suspensions 9a and 9b of the wheels 4a and 4b are coupled to each other 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 vertical 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 relative to each other in order to influence the roll behavior of the vehicle.

[0025] 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 gearbox 8, preferably designed as a multi-stage planetary gearbox, and a decoupling unit 10. The drive motor 7, the gearbox 8 and the decoupling unit 10 are arranged coaxially with respect to the axis of rotation 5 and are located within a housing 6 of the actuator 2.

[0026] Accordingly, the actuator 2 has a drive train comprising a drive unit consisting of a drive motor 7 and the gearbox 8 driven by it, which reduces a motor speed provided by the drive motor 7 into a relatively lower gearbox output speed, with which a [further specified] Fig. The drive element 11 of the decoupling unit 10, which is to be explained in section 2, can be driven. 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 axis of rotation 5 for the purpose of influencing the roll behavior of the vehicle equipped with it. This will be explained in more detail below. Fig. In the manner to be described, the drive train of actuator 2 comprises the decoupling unit 10.

[0027] Fig. Figure 2 shows a decoupling unit 10 according to the invention in a simplified schematic exploded view from a top oblique angle. The decoupling unit 10 is advantageously attached to a [position] as shown in Figure 2. Fig. 1. The actuator 2 or an actively adjustable roll stabilizer 1 of a motor vehicle is used. For orientation, the axis of rotation 5 is shown, which is intended to illustrate that the in Fig. 2 decoupling unit 10 shown with corresponding orientation in the in Fig. The chassis actuator 2 shown in 1 can be installed as a decoupling unit 10.

[0028] The essential elements include the in Fig. The decoupling unit 10 shown comprises a drive part 11 rotatable about the axis of rotation 5, an output part 12 rotatable about the axis of rotation 5, and a coupling acting between them. The coupling has a spring-damper unit acting between the drive part 11 and the output part 12, comprising a spring element 13 which torsionally couples the drive part 11 to the output part 12 and is provided with a metal mesh 18 for damping torsional vibrations. In the example shown, the spring element is designed as a spiral spring 13, which has a plurality of coils extending about the axis of rotation 5. In the example shown, the spiral spring 13 has six coils that extend in a helical shape from a first end 14, which has a maximum distance to the axis of rotation 5, to an inner second end 15, which is closest to the axis of rotation 5.The six helical coils of the spiral spring 13 run in a radial plane perpendicular to the axis of rotation 5. While the first end 14 is rotationally fixed to the drive part 11, the second end 15 is rotationally fixed to the output part 12. Accordingly, the spring element designed as a spiral spring 13 is suitable for transmitting at least part of a torque M1, indicated by a direction-of-rotation arrow, provided at the drive part 11 to the output part 12, at which a torque M2 (also indicated by a direction-of-rotation arrow) can be used.

[0029] How Fig. As can be seen from Figure 2, the drive part 11 and the output part 12 are designed to be pluggable into one another. For this purpose, a section of the drive part 11 is designed such that it can be inserted (starting from the separated state shown) into a circular opening 16 formed on the output part 12 of an adjoining cylindrical interior. The drive part 11 and the output part 12 can thus be joined together along a joining direction 17, parallel to the axial direction of the axis of rotation 5, for the assembly of the decoupling unit 10.

[0030] Several possibilities exist for connecting the first end 14 and the second end 15 of the coil spring 13 to the drive part 11 and the output part 12, respectively. The coil spring 13 is made of metal in one piece, in particular spring steel. The coil spring 13 couples the drive part 11 to the output part 12 in a torsionally elastic manner, i.e., ensuring a relative rotational movement between the drive part 11 and the output part 12.

[0031] Since torsional vibrations can occur within the drive train during the operational use of the landing gear actuator for various reasons, the spring element 13 is provided with a metal mesh 18 according to the invention, which dampens such torsional vibrations. The metal mesh 18 is formed from a fabric made of a metallic material.

[0032] Fig. Figure 3 shows an example of a spring-damper unit, formed from a spring element 13 and a metal mesh, which is arranged as in Fig. The decoupling unit 10 shown in Figure 2 according to the invention can be used. According to the illustration in Figure 2, the decoupling unit 10 can be used. Fig. In the example shown in 3, the metal mesh 18 is formed flatly, in particular in the form of a band that rests against the spring element 13. As in Fig. As shown in Figure 3, the metal mesh 18 is inserted into the coils of the spring element, which is designed as a spiral spring 13, and thus also runs spirally from approximately the first end 14 of the spiral spring to the second end 15 of the spiral spring. The metal mesh 18 is additionally attached to the spring element 13, in particular by bonding it.

[0033] The decoupling unit 10, as shown by Fig. 2, can be advantageously used on an actuator 2 of an actively adjustable roll stabilizer 1 of a motor vehicle, as shown by Fig.1 explained. By using a coupling made entirely of metal, which ensures a torsionally flexible coupling between the drive part 11 and the output part 12 as well as damping of operationally induced torsional vibrations, the actuator exhibits reduced temperature dependence. In particular, the damping characteristics of the decoupling unit 10 are only minimally affected by temperature. Accordingly, for an actuator equipped with the decoupling unit according to the invention, the calibration required for conventional decoupling units made of elastomer is unnecessary. The decoupling unit is easy to manufacture and assemble. Reference sign 1 adjustable roll stabilizer 2 Actuator 3a; 3b first stabilizer section; second stabilizer section 4a; 4b first wheel; second wheel 5 Rotation axis 6 cases 7 Drive motor 8 (multi-stage planetary) gearbox 9a; 9b first wheel suspension; second wheel suspension 10 decoupling unit 11 Drive unit 12 Output part 13 spiral spring 14 first end 15 second end 16 Opening 17 Leading direction 18 Metal knitting M1 Drive torque M2 output torque x Vehicle longitudinal direction y vehicle transverse direction z Vehicle lifting direction

Claims

[1] 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, wherein the coupling has a spring-damper unit acting between the drive part (11) and the output part (12), comprising at least one spring element (13) which torsionally couples the drive part (11) to the output part (12) and is provided with a metal mesh (18) for damping torsional vibrations, characterized by , that the at least one spring element is a spiral spring (13) with a plurality of turns extending around the axis of rotation (5), wherein a first end (14) of the spiral spring (13) is connected to the drive part (11) and a second end (15) of the spiral spring (13) is connected to the output part (12) in order to transmit a torque between the drive part (11) and the output part (12). [2] Decoupling unit according to claim 1, characterized by , that the spring-damper unit is connected on the drive side to the drive part (11) and on the output side to the output part (12). [3] Decoupling unit according to claim 1 or 2, characterized by , that the spring-damper unit comprises two spring elements each in the form of a coil spring (13), wherein the two coil springs (13) are arranged with opposite winding directions to each other acting between the drive part (11) and the driven part (12). [4] Decoupling unit according to any of the preceding claims, characterized by , that the at least one spring element (13) has a radial geometry comprising several radial sections, wherein a radial section has the shape of a circular arc, an involute, a line segment, a sigmoid, a sinusoid or a mixture thereof. [5] Decoupling unit according to any of the preceding claims, characterized by, that the drive part (11) and the driven part (12) are designed to be pluggable into each other in certain areas (17). [6] Decoupling unit according to any of the preceding claims, characterized by , that at least one spring element (13) is designed to be circumferential on the inside or on the outside with respect to the drive part (11). [7] Decoupling unit according to any of the preceding claims, characterized by , that the at least one spring element (13) has an axial geometry comprising several axial sections, wherein an axial section has the shape of a circular arc, an involute, a line segment, a sigmoid, a sinusoid or a mixture thereof. [8] Decoupling unit according to any of the preceding claims, characterized by , that the metal knit (18) is formed from a fabric made of a metallic material. [9] Decoupling unit according to any of the preceding claims, characterized by, that the metal knitting (18) surrounds the at least one spring element (13) in certain areas, in particular by the metal knitting (18) being designed as a tube which accommodates the at least one spring element (13). [10] Decoupling unit according to any of the preceding claims, characterized by , that the metal knitting (18) is formed in a flat shape and is in contact with at least one spring element (13), in particular that it is attached to it. [11] Decoupling unit according to any of the preceding claims, characterized by , that the metal knitting (18) is inserted into the at least one spring element designed as a spiral spring (13), in particular into its windings. [12] Actuator (2) for an actively adjustable roll stabilizer (1) of a motor vehicle, comprising a drive train capable of rotating a stabilizer section (3b) connectable to the actuator (2) about an axis of rotation (5) for the purpose of influencing the roll behavior of the motor vehicle, wherein the drive train comprises a decoupling unit (10) with a drive part (11) rotatable about the axis of rotation (5), an output part (12) rotatable about the axis of rotation (5) and a coupling acting between them, wherein the coupling comprises a spring-damper unit acting between the drive part (11) and the output part (12), comprising at least one spring element (13) which torsionally couples the drive part (11) to the output part (12) and is provided with a metal mesh (18) for damping torsional vibrations, characterized by, that the at least one spring element is a spiral spring (13) with a plurality of turns extending around the axis of rotation (5), wherein a first end (14) of the spiral spring (13) is connected to the drive part (11) and a second end (15) of the spiral spring (13) is connected to the output part (12) in order to transmit a torque between the drive part (11) and the output part (12). [13] Adjustable roll stabilizer (1) for a motor vehicle, comprising a first stabilizer section (3a) that can be coupled to a first wheel suspension (9a) and a second stabilizer section (3b) that can be coupled to a second wheel suspension (9b), wherein the first stabilizer section (3a) and the second stabilizer section (3b) are rotatable relative to each other about the axis of rotation (5) by means of an actuator (2) acting between them according to claim 12 in order to influence the roll behavior of the motor vehicle.

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