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 clutch acting between them, is characterized in that the clutch has a spring-damper unit acting between the drive part (11) and the output part (12), comprising at least one spring element (13) which couples the drive part (11) to the output part (12) in a torsionally elastic manner and is provided with a metal mesh (18) for damping torsional vibrations.

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 13. Furthermore, the invention relates to an adjustable roll stabilizer for a motor vehicle according to claim 14.

[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, comprising 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 spring-damper unit acting between the drive part and the output part, comprising at least one spring element that torsionally elastically couples the drive part to the output part and is provided with a metal mesh to dampen torsional vibrations.

[0007] Accordingly, 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, whereby the decoupling unit or an actuator equipped with it has a significantly temperature-dependent damping characteristic. If the resulting inaccuracies in control during operation are not to be accepted, a complex calibration of the actuator equipped with the decoupling unit is necessary. According to the invention, an alternative possibility for designing a coupling was found to remedy this problem. Accordingly, the coupling has a spring-damper unit that is arranged so as to act between the drive part and the output part, wherein the at least one spring element of the spring-damper unit couples the drive part to the output part in a torsionally elastic manner.By additionally providing the at least one spring element with a metal mesh, damping of torsional vibrations is advantageously achieved. The metal mesh accordingly serves the function of damping movements of the at least one spring element, particularly those caused by relative rotational movements of the output part relative to the drive part. Various configurations are conceivable.

[0008] The spring-damper unit, essentially comprising the at least one spring element provided with the metal mesh, is expediently connected to the drive part on the drive side and to the output part on the output side. The at least one spring element and the metal mesh can be configured in various ways.

[0009] A structurally advantageous embodiment of the decoupling unit provides that the at least one spring element is a spiral spring with a plurality of turns extending around the rotational axis, 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 torque between the drive part and the output part. Accordingly, the spring element is a machine element that establishes a torsionally elastic coupling between the drive part and the output part and is suitable for torque transmission.

[0010] According to an advantageous development, the spring-damper unit can also comprise two spring elements, each in the form of a spiral spring, instead of a single spiral spring. In this case, the two spiral springs are advantageously arranged between the drive part and the output part with opposite winding directions. The arrangement of two spiral springs with opposite winding directions results in a symmetrical effect of the spring-damper unit, independent of the direction of rotation, since one spiral spring winds up and one unwinds in each direction of rotation.

[0011] Advantageously, the at least one spring element has a radial geometry comprising a plurality of radial sections, wherein a radial section has the shape of a circular arc, an involute, a line segment, a sigmoid, a sinusoid or a mixed form thereof.

[0012] The drive part and the output part can be designed in different ways. According to a preferred embodiment of the decoupling unit, the drive part and the output part are designed to be interlockable in certain areas.

[0013] The design and arrangement of the at least one spring element is conceivable in various ways. A preferred embodiment of the decoupling unit provides for the at least one spring element to be designed to extend either internally or externally relative to the drive part. For this purpose, the drive part and / or the driven part can have an opening, for example, be designed to be hollow in some areas, so that, for example, the drive part can be partially inserted into the driven part. To protect against contamination from the external environment, the at least one spring element can also be arranged within the formed cavity.

[0014] Preferably, the at least one spring element has an axial geometry comprising a plurality of axial sections, wherein an axial section has the shape of a circular arc, an involute, a line segment, a sigmoid, a sinuoid or a mixed form thereof.

[0015] To achieve the damping effect according to the invention, the metal mesh is advantageously formed from a fabric consisting of a metallic material.

[0016] 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 nature (metal mesh), the metal mesh counteracts this deformation, which is also a movement, with a resistance (damping force), which imparts a damping effect to the spring-damper unit.

[0017] A preferred development provides that the metal mesh surrounds the at least one spring element in some areas, in particular in that the metal mesh is designed as a tube which accommodates the spring element.

[0018] Alternatively or additionally, it can be provided that the metal mesh is flat and rests against the at least one spring element, in particular is fastened thereto, for example glued thereto.

[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 mesh is inserted into the at least one spring element designed as a spiral spring, in particular in its windings.

[0020] The object mentioned at the outset is further achieved by an actuator according to the features of claim 13. This is an actuator for an adjustable roll stabilizer of a motor vehicle, comprising a drive train suitable for rotating a stabilizer section connectable to the actuator about a rotational axis for the purpose of influencing the roll behavior of the motor vehicle. The drive train has a decoupling unit with a drive part rotatable about the rotational axis, an output part rotatable about the rotational axis, and a clutch acting therebetween. According to the invention, the actuator is characterized in that the clutch has a spring-damper unit acting between the drive part and the output part, comprising at least one spring element which torsionally elastically couples the drive part to the output part and is provided with a metal mesh for damping torsional vibrations.With regard to the effects and advantages that can be achieved with the actuator according to the invention, reference is made to the previous statements regarding the decoupling unit according to the invention, which also apply equally to the actuator.

[0021] The object mentioned at the outset is further achieved by an adjustable roll stabilizer for a motor vehicle according to the features of claim 14. 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.

[0022] The invention is explained and described in more detail below with reference to the accompanying drawings. Further advantageous effects of the invention will also emerge. The drawing shows: Fig. 1 an actively adjustable roll stabilizer in a simplified schematic representation from above, Fig. 2 a decoupling unit for an actuator of a vehicle as in Fig. 1 shown adjustable roll stabilizer in simplified exploded view from diagonally above, Fig. 3 a spring-damper unit in a simplified representation, which is basically attached to a Fig. 2 can be used.

[0023] 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.

[0024] 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.

[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 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.

[0026] 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.

[0027] Fig. Figure 2 shows a decoupling unit 10 according to the invention in a simplified schematic exploded view obliquely from above. The decoupling unit 10 is advantageously used on a Fig. 1 or an actively adjustable roll stabilizer 1 of a motor vehicle. For orientation, the rotation axis 5 is shown, which should make it clear that the Fig. 2 shown decoupling unit 10 with corresponding alignment in the Fig. 1 can be installed as a decoupling unit 10.

[0028] The essential elements include Fig. The decoupling unit 10 shown in Figure 2 comprises a drive part 11 rotatable about the rotation axis 5, an output part 12 rotatable about the rotation axis 5, and a coupling acting therebetween. 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 elastically couples the drive part 11 to the output part 12 and is provided with a metal mesh 18 to dampen torsional vibrations. In the example shown, the spring element is designed as a spiral spring 13 having a plurality of turns extending around the rotation axis 5. In the example shown, the spiral spring 13 has six turns which extend in a helical shape from a first end 14, which is at a maximum distance from the rotation axis 5, to an inner second end 15, which is closest to the rotation axis 5.The six helical coils of the spiral spring 13 extend in a radial plane perpendicular to the rotational axis 5. While the first end 14 is rotationally fixedly connected to the drive part 11, the second end 15 is rotationally fixedly connected to the output part 12. Accordingly, the spring element designed as a spiral spring 13 is suitable for at least partially transmitting a torque M1 provided at the drive part 11, indicated by a direction of rotation arrow, 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 in Figure 2, the drive part 11 and the output part 12 are designed to be plugged into one another. For this purpose, a portion of the drive part 11 is designed such that it (starting from the separated state shown) can be inserted into a circular opening 16 formed on the output part 12 in an adjoining cylindrical interior space. The drive part 11 and the output part 12 can thus be joined along a joining direction 17, parallel to the axial direction of the rotation axis 5, for assembling the decoupling unit 10.

[0030] Various possibilities are conceivable 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 a single piece of metal, 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 drivetrain during operational use of the chassis 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. 3 shows an example of a spring-damper unit, formed from a spring element 13 and a metal mesh, which is arranged in a manner as shown in Fig. 2 shown decoupling unit 10 according to the invention can be used. According to the Fig. 3, the metal mesh 18 is formed flat, in particular in the form of a band that rests on 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 embodied as a spiral spring 13, thus also extending in a spiral shape approximately from 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, glued thereto.

[0033] The decoupling unit 10, as shown in Fig. 2, can be used advantageously on an actuator 2 of an actively adjustable roll stabilizer 1 of a motor vehicle, as can be seen from Fig.1. By using a coupling made entirely of metal, which ensures a torsionally flexible coupling of the drive part 11 and the output part 12 as well as damping operational torsional vibrations, the actuator exhibits reduced temperature dependence. In particular, the damping characteristics of the decoupling unit 10 are only slightly influenced by temperature. Accordingly, an actuator equipped with the decoupling unit according to the invention can eliminate the need for calibration, as is necessary with conventional decoupling units made of elastomer. The decoupling unit is easy to manufacture and assemble. 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 Spiral spring 14 first end 15 second end 16 Opening 17 Joining direction 18 metal mesh 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 spring-damper unit acting between the drive part (11) and the output part (12), comprising at least one spring element (13) which torsionally elastically couples the drive part (11) to the output part (12) and is provided with a metal mesh (18) for damping torsional vibrations. [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 byin that the at least one spring element is a spiral spring (13) with a plurality of turns running 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). [4] Decoupling unit according to claim 3, characterized by that the spring-damper unit comprises two spring elements, each in the form of a spiral spring, wherein the two spiral springs are arranged with opposite winding directions between the drive part and the output part. [5] Decoupling unit according to one of the preceding claims, characterized bythat the at least one spring element has a radial geometry comprising a plurality of radial sections, wherein a radial section has the shape of a circular arc, an involute, a line segment, a sigmoid, a sinusoid or a mixed form thereof. [6] Decoupling unit according to one of the preceding claims, characterized by that the drive part (11) and the output part (12) are designed to be pluggable into one another in some areas (17). [7] Decoupling unit according to one of the preceding claims, characterized by that the at least one spring element (13) is designed to be internally circumferential or externally circumferential with respect to the drive part (11). [8] Decoupling unit according to one of the preceding claims, characterized bythat the at least one spring element has an axial geometry which comprises a plurality of axial sections, wherein an axial section has the shape of a circular arc, an involute, a line segment, a sigmoid, a sinusoid or a mixed form thereof. [9] Decoupling unit according to one of the preceding claims, characterized by that the metal mesh (18) is formed from a fabric consisting of a metallic material. [10] Decoupling unit according to one of the preceding claims, characterized by that the metal mesh (18) surrounds the at least one spring element (13) in some areas, in particular in that the metal mesh (18) is designed as a hose which accommodates the at least one spring element (13). [11] Decoupling unit according to one of the preceding claims, characterized by that the metal mesh (18) is flat and rests against the at least one spring element (13), in particular is fastened thereto. [12] Decoupling unit according to one of the preceding claims, characterized by that the metal mesh (18) is inserted into the at least one spring element designed as a spiral spring (13), in particular in its windings. [13] 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 bythat 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 elastically couples the drive part (11) to the output part (12) and is provided with a metal mesh (18) for damping torsional vibrations. [14] 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 13 in order to influence a roll behavior of the motor vehicle.

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