DE102021207283B4 - Adjustable roll stabilizer - Google Patents

Abstract

Adjustable roll stabilizer (1) for a motor vehicle, with two stabilizer sections (2a, 2b) which can be rotated relative to one another about a rotation axis (7) by means of an actuator (6) arranged between the stabilizer sections (2a, 2b), wherein the actuator (6) has a housing (8) and a drive device (9) arranged therein with an output element (10) which is supported by a bearing device (13) so as to be rotatable about the rotation axis (7) relative to the housing (8) and is drive-connected to a stabilizer section (2b), wherein the bearing device (13) comprises two roller bearings (21, 22) with an inner ring (23, 24), an outer ring (25) and a row of rolling elements (26, 27), characterized in that the inner ring (24) of an outer roller bearing (22) is axially supported on both sides relative to the output element (10) is fixed, while the inner ring (23) of an inner rolling bearing (21) is axially sprung relative to the output element (10).

Description

The invention relates to an adjustable roll stabilizer for a motor vehicle according to the preamble of claim 1.

In automotive engineering, it is known to equip vehicles with a so-called roll stabilizer in order to increase vehicle stability and driving comfort. In a simple version, this is essentially a C-shaped torsion bar spring, which is mounted in the middle area so that it can rotate relative to the body and whose outer, opposite ends are each coupled to a wheel suspension. With this design, the roll stabilizer ensures that the body of the vehicle does not only compress on the outside side when cornering (due to centrifugal force), but that the wheel on the inside of the curve is also lowered slightly (copying behavior).

To further increase driving comfort, it is known from the prior art to make such roll stabilizers adjustable. The roll stabilizer comprises an actuator and is divided into two stabilizer sections that can be rotated relative to one another using the actuator. By rotating the stabilizer sections relative to one another - around an axis of rotation - a rolling movement of the vehicle body is deliberately generated or a rolling movement of the vehicle body caused by external influences is deliberately counteracted. Known adjustable roll stabilizers are equipped with an actuator that essentially has a housing and a drive device arranged therein, comprising an electric motor and a gear connected to it for driving purposes, in particular in the form of a multi-stage planetary gear. DE 10 2015 220 176 A1 Such an adjustable roll stabilizer for a motor vehicle is known.

In previously known adjustable roll stabilizers, the electric motor and a multi-stage planetary gear driven by it are arranged coaxially with respect to the axis of rotation of the roll stabilizer. Due to the design, the housing is essentially cylindrical, with one of the stabilizer sections being connected in a rotationally fixed manner to one axial end of the housing, while the second, opposite stabilizer section is in drive connection with an output element assigned to the drive device at the opposite axial end of the housing. The output element can be, for example, a planet carrier of the highest (output-side) stage of the multi-stage planetary gear, as in DE 10 2015 220 176 A1 . The output element is supported by a bearing device so that it can rotate about the axis of rotation relative to the housing of the actuator, and the output element is also connected to the associated stabilizer section, for example welded to it or screwed via a flange connection. In the previously mentioned adjustable roll stabilizer, the bearing device of the output element comprises, according to the 2 two rolling bearings designed as double-row angular contact ball bearings. The inner ring of the outer rolling bearing in relation to the actuator housing is axially preloaded by a locking element in the form of a special nut screwed axially from the outside onto the output element. During assembly, too much preload can easily occur within the entire bearing device, which can adversely squeeze the ball sets of both rolling bearings. As a result, permanent deformation such as brinelling of the running surface and/or flattening of the rolling elements can occur.

DE 10 2014 202 829 A1 discloses an adjustable roll stabilizer having features of the preamble of claim 1. In addition, a preloading element is provided which has a union nut screwed onto the output shaft and a spring element which is arranged between the union nut and the inner ring of the outer rolling bearing.

From the republished DE 10 2020 122 886 A1 An adjustable roll stabilizer according to the features of the preamble of claim 1 is known. The inner ring of the inner rolling bearing is axially sprung relative to the output element.

It is an object of the present invention to provide an adjustable roll stabilizer of the type mentioned at the outset, which has a bearing of the output element which is improved in terms of robustness, wherein, while ensuring a high tilting stiffness of the bearing, the susceptibility to errors during assembly is at the same time achieved, in particular by granting larger tolerances of the tightening torque.

The object is achieved by an adjustable roll stabilizer for a motor vehicle according to the features of claim 1. According to the invention, this is an adjustable roll stabilizer with two stabilizer sections that can be rotated relative to one another about a rotation axis by means of an actuator arranged between the stabilizer sections. The actuator has a housing and a drive device arranged therein with an output element. The output element is connected to the drive device by means of a bearing device. rotatable about the axis of rotation, supported relative to the housing and drive-connected to a stabilizer section. The bearing device comprises two roller bearings with an inner ring, an outer ring and a series of rolling elements. According to the invention, the adjustable roll stabilizer is characterized in that the inner ring of the outer roller bearing is axially fixed on both sides relative to the output element, while the inner ring of the inner roller bearing is axially spring-loaded relative to the output element.

The combination of features according to the invention provides that the bearing device of the output element further comprises two roller bearings, which can be axially spaced apart from one another to absorb high bending moments acting on the roll stabilizer. Since of the two roller bearings only the inner ring of the outer roller bearing is axially fixed relative to the output element, the inner ring of the inner roller bearing is not axially fixed relative to the output element, but represents a loose bearing due to a certain axial spring-loaded mobility. Due to the spring loading, which will be explained later, the interaction results in a play-free bearing, whereby the axial springing of the inner ring of the inner roller bearing implements an adjustment function of the bearing device. At the same time, the axial springing ensures that a permissible preload force within the bearing device is not exceeded even with excessive tightening torques of the locking element of the outer roller bearing. The risk of incorrect assembly is thus reduced. The axial springing of the inner ring of the inner rolling bearing helps to compensate for tightening torque tolerances.

According to an advantageous embodiment, the inner and the outer rolling bearing have a common outer ring.

In principle, the rolling bearings can be of various conceivable types. According to an advantageous development of the adjustable roll stabilizer, the inner and outer rolling bearings are designed as angular contact ball bearings aligned in an O arrangement. The bearing device can therefore absorb relatively high tilting moments despite an axially limited installation space.

To increase the robustness of the bearing, particularly with regard to acting bending moments, the inner and outer rolling bearings each have structurally separate, axially spaced inner rings.

To achieve simple and error-free assembly and effective power transmission, the common outer ring is fixed axially on both sides relative to the housing, so that the outer rolling bearing serves as a fixed bearing of the bearing device.

According to a preferred development of the bearing, the inner ring of the outer rolling bearing is supported axially on the inside against the output element, in particular against a shoulder formed thereon, and rests axially on the outside against a securing element that can be applied to the output element, preferably in the form of a screw-on nut.

It is expediently provided that the inner ring of the inner rolling bearing is axially displaceable relative to the output element - at least to a certain extent.

A preferred development of the adjustable roll stabilizer provides that the inner ring of the inner roller bearing is supported axially by means of a spring element relative to the output element, in particular relative to a shoulder formed thereon. The spring element can be, for example, a spring acting in the axial direction, such as a disc spring or spiral spring.

Advantageously, in the assembled state, i.e. when the locking element is applied, the spring element between the shoulder and the inner ring of the inner roller bearing is deformed in the axial direction, so that it exerts a restoring force in the axial direction in the sense of a preload on the inner ring of the inner roller bearing. The preload applied by the spring element, in combination with the axial displaceability of the inner ring of the inner roller bearing, advantageously enables an adjustment function and/or tolerance compensation in relation to the applied tightening torque during assembly. The risk of assembly errors can thus be reduced.

In principle, the rolling bearings used according to the invention can be of the same type. Due to the different arrangement of the inner rings of the outer and inner rolling bearings provided according to the invention, an advantageous design of the bearing device can be achieved in that the rolling elements of the outer rolling bearing have a larger diameter than the rolling elements of the inner rolling bearing, so that the outer rolling bearing has a larger load capacity than the inner rolling bearing.

An adjustable roll stabilizer is used in different environments influences such as moisture, dirt, temperature, exhaust gases and the like. It is therefore known that there is a need to seal the output element, which can rotate about the axis of rotation, from the housing of the actuator in order to prevent undesirable substances from penetrating into the interior of the housing. In particular with an asymmetrical bearing design as described above (larger rolling elements of the outer bearing than the inner bearing), the different dimensions of the bearing rings can provide the advantageous option of integrating a seal into the outer rolling bearing which prevents moisture from penetrating from the outside into the interior of the housing. By integrating a seal into the bearing in this way, a seal conventionally arranged outside the axial securing element of the output element can be dispensed with, which simplifies the assembly of the adjustable roll stabilizer because there are fewer components to handle.

Depending on the design requirements of the adjustable roll stabilizer, actuators are known whose multi-stage planetary gear, which can be driven by the electric motor, is directly connected to the output element of the drive device. In this case, the output element is in particular in the planet carrier of the multi-stage planetary gear.
Alternatively, adjustable roll stabilizers are known whose drive train has a coupling between the electric motor and the output element, which serves to dampen torsional vibrations in the drive train. In this case, the output element referred to here is connected to a planet carrier of a multi-stage planetary gear via a coupling. The invention described above can be used on adjustable roll stabilizers of both types mentioned - with and without a torsion-damping coupling - in a similar way.

• 1 einen verstellbaren Wankstabilisator für ein Kraftfahrzeug in schematischer Ansicht,
• 2 einen schematisch und vereinfacht dargestellten bekannten Aktuator eines verstellbaren Wankstabilisators in Schnittdarstellung,
• 3 eine Lagereinrichtung eines Aktuators eines erfindungsgemäßen verstellbaren Wankstabilisators in teilweiser Schnittdarstellung,
• 4 eine Variante einer Lagereinrichtung.

The invention is described below with reference to the drawing, in which:

• 1 an adjustable roll stabilizer for a motor vehicle in schematic view,
• 2 a schematic and simplified known actuator of an adjustable roll stabilizer in sectional view,
• 3 a bearing device of an actuator of an adjustable roll stabilizer according to the invention in a partial sectional view,
• 4 a variant of a storage facility.

First, 1 to illustrate the field of application of the invention, an adjustable roll stabilizer 1 for a motor vehicle in a schematic, perspective view. The roll stabilizer 1 is part of a chassis of a motor vehicle, not shown in full. A wheel 3a and a wheel 3b arranged on the opposite side of the vehicle are each connected to a body of the motor vehicle (not shown) via a wheel suspension 4a or 4b. Each of these wheel suspensions 4a and 4b is coupled to one end of an associated stabilizer section 2a or 2b of the adjustable roll stabilizer 1 via an associated pendulum support 5a, 5b. The two stabilizer sections 2a and 2b are connected to one another in the middle of the vehicle via an actuator 6.

In a manner known per se, the roll stabilizer 1 is mounted so as to be rotatable about a rotation axis 7 relative to the vehicle body (not shown). The actuator 6, in 1 shown in simplified form as a cylindrical body, essentially comprises a housing 8 in which a drive device 9 is arranged. The drive device 9 comprises, in a manner known per se, an electric motor 11 and a multi-stage planetary gear 12 which is in driving connection thereto and which are arranged coaxially with respect to the axis of rotation 7. The stabilizer sections 2a and 2b are in driving connection via the drive device 9. When the electric motor is stationary, the two stabilizer sections 2a, 2b are rigidly connected to one another via the actuator 6. By operating the electric motor, the stabilizer sections 2a, 2b can be rotated relative to one another around the axis of rotation 7 depending on the direction of rotation of the electric motor. The roll stabilizer 1 can thus be adjusted in a manner known per se.

2 shows, for illustration purposes and to explain the functionality, an actuator 6 in a sectional view, which is used in an adjustable roll stabilizer as in 1 shown, can be used. According to the sectional view, it can be seen that the actuator 6 extends between the stabilizer section 2a and the stabilizer section 2b along the axis of rotation 7. In the housing 8, in an area of the housing 8 facing the stabilizer section 2a, an electric motor 11 is arranged, which is in driving connection with a three-stage planetary gear 12. The electric motor 11 and the multi-stage planetary gear 12 form essential components of the drive device 9 of the actuator 6 with an output element 10, which is mounted relative to the housing by means of a bearing device 13 so as to be rotatable about the axis of rotation 7. The output element 10 is - as indicated in the drawing - drive-connected to the stabilizer section 2b, for example welded or screwed to it. On the other hand, the stabilizer section 2a is non-rotatably connected to the opposite axial end of the housing 8. connected. The 2 The illustrated storage device 13 corresponds to the state of the art.

3 shows, in contrast, a bearing device 13 of an adjustable roll stabilizer according to an embodiment of the invention. An axial end of the housing 8 of an actuator of an adjustable roll stabilizer, facing the stabilizer section 2b, is shown in partial section. A planet carrier 14 is assigned to the last, for example third stage of the three-stage planetary gear arranged in the housing. The planet carrier 14 is in drive connection with the output element 10 via a clutch 15 (not explained in more detail). The output element 10 can be rotated about the axis of rotation by means of a bearing device 13 (to be explained) (cf. 1 and 2 ) is mounted opposite the housing 8. The output element 10 is firmly connected to the stabilizer section 2b in a manner only indicated by the reference numeral for driving the latter.

The bearing device 13 comprises two rolling bearings 21, 22 designed as angular contact ball bearings. An inner rolling bearing 21 with respect to the housing 8 has an inner ring 23, an outer ring 25 and a series of rolling elements 26. An outer rolling bearing 22 with respect to the housing 8 has an inner ring 24, the outer ring 25 and a series of rolling elements 27.

The spherical rolling elements 26, 27 of the inner rolling bearing 21 and the outer rolling bearing 22 are axially spaced from one another. The inner ring 24 of the outer rolling bearing 22 is axially fixed on both sides relative to the output element 10 in that it is supported axially on the inside relative to a shoulder 19 formed on the output element 10. Axially on the outside there is a locking element 28 in the form of a screw-on nut which is screwed onto a thread formed on the output element 10, with the locking element 28 axially on the outside of the inner ring 24, whereby the inner ring 24 is axially fixed between the shoulder 19 and the locking element 28 without play.

In contrast, the inner ring 23 of the inner roller bearing 21 is spring-loaded so as to be axially displaceable relative to the output element 10. As in 3 As can be seen, the inner ring 23 is supported axially by means of a spring element 30 against a shoulder 20 formed on the output element 10, so that the inner ring 23 can only be moved in the direction of the shoulder 20 against a spring force of the spring element 30. The spring element 30 is, for example, a disc spring or spiral spring.
While the inner rolling bearing 21 and the outer rolling bearing 22 have structurally separate, axially spaced inner rings 23 and 24, the inner rolling bearing 21 and the outer rolling bearing 22 share the common outer ring 25. The outer ring 25 is axially fixed between a shoulder 18 of the housing 8 and a locking element 29 screwed in after assembly of the outer ring 25.

The inner rolling bearing 21 and the outer rolling bearing 22 are designed as angular contact ball bearings aligned in an O-arrangement.

The rolling elements 27 of the outer rolling bearing 22 have a larger diameter than the rolling elements 26 of the inner rolling bearing 21, so that the outer rolling bearing 22 has a larger load rating than the inner rolling bearing 21.

In an assembled state as shown, i.e. with the securing element 28 applied, the spring element 30 is compressed in the axial direction between the shoulder 20 and the inner ring 23 of the inner roller bearing 21, so that due to the deformation of the spring element 30, it exerts a restoring force in the axial direction in the sense of a preload on the inner ring 23 of the inner roller bearing 21. This results in a play-free bearing arrangement of the two angular contact ball bearings 21 and 22, and an adjustment function is also ensured by the spring force.

The interior of the housing 8 is sealed by a seal 17 which extends in an annular space between the output element 10 and an axial end of the housing 8. The seal 17 comprises a radial shaft seal as an essential element. The seal 17 is positioned axially outside the securing elements 28 and 29.

4 shows a variation compared to the design of 3 in terms of sealing. In contrast to the design according to 3 is at the in 4 In the modification shown in Figure 1, a seal 16 is integrated into the outer roller bearing 22, which prevents the penetration of moisture from the outside into the interior of the housing 8. In the case of the 4 In the modification shown, the seal 16 extends between the inner ring 24 of the outer rolling bearing 22 and the common outer ring 25. A radial shaft seal is again used as the essential sealing element, whereby the integration into the rolling bearing 22 means that an additional seal located axially outside the securing elements 28 or 29 can be omitted in favor of easier assembly and a reduction in parts.

It should be noted that, in contrast to the 3 shown design the output element a planet carrier of a multi-stage planetary gear.

reference sign

1

adjustable roll stabilizer

2a, 2b

stabilizer section

3a, 3b

wheel

4a, 4b

suspension

5a, 5b

pendulum support

6

actuator

7

axis of rotation

8

Housing

9

drive device

10

output element

11

electric motor

12

multi-stage planetary gear

13

storage facility

14

output-side planet carrier

15

coupling

16

seal

17

seal

18

Paragraph

19

Paragraph

20

Paragraph

21

inner rolling bearing

22

outer rolling bearing

23

inner ring inner rolling bearing

24

inner ring outer rolling bearing

25

common outer ring

26

rolling elements inner rolling bearing

27

rolling element outer rolling bearing

28

securing element

29

securing element

Claims (13)

Adjustable roll stabilizer (1) for a motor vehicle, with two stabilizer sections (2a, 2b) which can be rotated relative to one another about a rotation axis (7) by means of an actuator (6) arranged between the stabilizer sections (2a, 2b), wherein the actuator (6) has a housing (8) and a drive device (9) arranged therein with an output element (10) which is supported by a bearing device (13) so as to be rotatable about the rotation axis (7) relative to the housing (8) and is drive-connected to a stabilizer section (2b), wherein the bearing device (13) comprises two roller bearings (21, 22) with an inner ring (23, 24), an outer ring (25) and a series of rolling elements (26, 27), characterized in that the inner ring (24) of an outer roller bearing (22) is axially supported on both sides relative to the output element (10), while the inner ring (23) of an inner rolling bearing (21) is axially sprung relative to the output element (10). Adjustable roll stabilizer according to Claim 1 , characterized in that the inner and the outer rolling bearing (21, 22) have a common outer ring (25). Adjustable roll stabilizer according to Claim 1 or 2 , characterized in that the inner and the outer rolling bearing (21, 22) are designed as angular contact ball bearings aligned with each other in an O-arrangement. Adjustable roll stabilizer according to one of the preceding claims, characterized in that the inner and the outer rolling bearing (21, 22) each have structurally separate, axially spaced inner rings (23, 24). Adjustable roll stabilizer according to one of the Claims 2 until 4 , characterized in that the common outer ring (25) is fixed axially on both sides relative to the housing (8), so that the outer rolling bearing (22) serves as a fixed bearing of the bearing device (13). Adjustable roll stabilizer according to one of the preceding claims, characterized in that the inner ring (24) of the outer roller bearing (22) is supported axially on the inside against the output element (10), in particular against a shoulder (19) formed thereon, and axially on the outside against a securing element (28) that can be applied to the output element (10), preferably in the form of a screw-on nut. Adjustable roll stabilizer according to one of the preceding claims, characterized in that the inner ring (23) of the inner rolling bearing (21) is axially displaceable relative to the output element (10). Adjustable roll stabilizer according to one of the preceding claims, characterized in that the inner ring (23) of the inner rolling bearing (21) is axially displaced relative to the output element (10), in particular against a shoulder (20) formed thereon. Adjustable roll stabilizer according to claim 8 , characterized in that in the assembled state, thus with the securing element (28) applied, the spring element (30) between the shoulder (20) and the inner ring (23) of the inner rolling bearing (21) is deformed in the axial direction, so that it exerts a restoring force in the axial direction in the sense of a preload on the inner ring (23) of the inner rolling bearing (21). Adjustable roll stabilizer according to one of the preceding claims, characterized in that the rolling elements (27) of the outer rolling bearing (22) have a larger diameter than the rolling elements (26) of the inner rolling bearing (21), so that the outer rolling bearing (22) has a larger load rating than the inner rolling bearing (21). Adjustable roll stabilizer according to one of the preceding claims, characterized in that a seal (16) is integrated into the outer rolling bearing (22), which seal prevents the penetration of moisture from the outside into the interior of the housing (8). Adjustable roll stabilizer according to one of the preceding claims, characterized in that the output element (10) is a planet carrier of a multi-stage planetary gear (12). Adjustable roll stabilizer according to one of the Claims 1 until 11 , characterized in that the output element (10) is in drive connection via a clutch (15) with a planet carrier (14) of a multi-stage planetary gear (12).

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