CN111373632A

CN111373632A - Stabilizer actuator with permanent magnet motor

Info

Publication number: CN111373632A
Application number: CN201880075935.2A
Authority: CN
Inventors: V·舒尔迈尔
Original assignee: ZF Friedrichshafen AG
Current assignee: ZF Friedrichshafen AG
Priority date: 2017-11-24
Filing date: 2018-10-25
Publication date: 2020-07-03
Also published as: WO2019101467A1; EP3714526A1; DE102017221030A1

Abstract

A stabilizer actuator (6) is proposed for the relative rotation of two stabilizer parts (2, 3) of an anti-roll stabilizer (1), having a housing (7) and a permanent magnet motor (9) arranged therein for torque introduction and comprising a stator (11) which is connected to the housing (7) in a rotationally fixed manner and a rotor (12) which is mounted rotatably relative thereto about a rotational axis (13), wherein the stator (11) has a plurality of stator slots which extend in the axial direction and accommodate coil windings, and wherein the rotor (12) has a plurality of magnet segments which extend in the axial direction and are supported by a rotor core, in the circumferential direction. The stator slots or magnet segments each have an inclination to reduce cogging, so that they extend over their entire axial length in the axial and circumferential direction of the stator (11) and/or rotor (12). The invention further relates to an anti-roll stabilizer (1) for a motor vehicle, comprising such a stabilizer actuator (6).

Description

Stabilizer actuator with permanent magnet motor

Technical Field

The present invention relates to a stabilizer actuator for relative rotation of two stabilizer parts of an anti-roll stabilizer, in particular for a motor vehicle, according to the type defined in detail in the preamble of the independent claim. Furthermore, the invention relates to an anti-roll stabilizer with such a stabilizer actuator according to the preamble of the further independent claim.

Background

The stabilizer actuators known from the prior art comprise permanent magnet motors which, due to their slot opening, have an undesirable cogging (nutasten). This leads to various disturbances in the course of the movement and influences the accuracy and dynamics of the adjustment of the stabilizer actuator.

Disclosure of Invention

It is therefore an object of the invention to improve the adjustment accuracy and dynamics of the stabilizer actuator.

The object on which the invention is based is achieved by the features of the independent claims. Further advantageous embodiments emerge from the dependent claims and the drawings.

A stabilizer actuator is proposed for relative rotation of two stabilizer parts of an anti-roll stabilizer. The stabilizer actuator is preferably arranged as an active anti-roll stabilizer for a motor vehicle. The stabilizer actuator includes a housing and a permanent magnet motor disposed in the housing. The permanent magnet motor is arranged for introducing a torque. The permanent magnet motor comprises a stator which is connected to the housing in a rotationally fixed manner. The permanent magnet motor also has a rotor rotatably mounted relative to the housing about a rotational axis. The stator has a plurality of stator slots extending in the axial direction and accommodating coil windings in the circumferential direction. Furthermore, the rotor has a rotor core. Furthermore, the rotor comprises in the circumferential direction a plurality of magnet segments extending in the axial direction and supported by the rotor core. To reduce cogging, the stator slots or magnet segments have respective ramps.

By means of the inclination, the stator slot or the magnet section is designed in such a way that it extends over its entire axial length in the axial direction as well as in the circumferential direction of the stator and/or the rotor. Thus, they do not run parallel to the axis of rotation, but rather run, in plan view, in particular continuously or in steps, obliquely to the axis of rotation. Cogging can be advantageously reduced, whereby the adjustment accuracy and power of the stabilizer actuator can be improved.

Advantageously, the inclined portion is continuous. In this case, the inclined portion has a continuous slope course extending obliquely to the axis of rotation. Therefore, the slope trend is not abrupt.

In this connection, it is also advantageous if the slope of the continuous slope course is constant. The inclined portion and/or its inclination is thus straight.

In an advantageous development of the invention, the magnet sections are arranged at the rotor core in an inclined manner in order to form a continuous inclined portion with respect to the axis of rotation. Alternatively, however, it is also advantageous if the magnet section has a basic shape which is a parallelogram in top view in order to form a continuous inclined section. In addition or alternatively, the longitudinal sides of the magnet segments preferably do not run parallel to the axis of rotation in plan view, but rather run obliquely to the axis of rotation.

In addition to the continuous inclined portion described above, the inclined portion is advantageously formed stepwise. The inclined portion thus has a stepped slope profile extending obliquely to the axis of rotation. The slope course therefore has at least one, but preferably a plurality of steps.

The stepped inclination can be formed particularly cost-effectively if the magnet segments preferably each comprise at least two segment parts which are adjacent to one another in the axial direction and have a circumferential offset from one another. Preferably, the segment parts extend only in the axial direction and do not extend in the circumferential direction over their entire axial length. They therefore preferably have a rectangular basic shape in plan view. In addition or alternatively, the longitudinal sides of the segment parts preferably run parallel to the axis of rotation in plan view.

It is also advantageous if the magnet segments lie against one another or are spaced apart from one another in the circumferential direction.

In an advantageous development of the invention, the magnet segments are each fixed to the outer periphery of the rotor by a radially inner connecting surface, in particular adhesively bonded thereto.

In order to be able to produce the magnet segments as cost-effectively as possible, it is advantageous if the connection faces of the magnet segments are formed flat and the outer periphery of the rotor core has a chamfer corresponding to the flat connection face. The magnet segments are therefore preferably bonded by their flat connecting surfaces to the respectively corresponding inclined surfaces.

Alternatively, it is advantageous if the connection face of the magnet section is concave in the end-side view, so that it corresponds to the outer circumferential circle of the rotor core.

In a further alternative embodiment, it is advantageous if the rotor core has a plurality of recesses extending in the axial and/or circumferential direction in the circumferential direction, in which the magnet segments are accommodated. Preferably, the recess extends over its entire axial length only in the axial direction and not in the circumferential direction. Thereby reducing manufacturing costs.

Advantageously, in order to form a stepped slope, the rotor core comprises at least two rotor core sections adjacent to each other in the axial direction, which rotate relative to each other. By this rotation, the magnet segments of the two rotor core segments have a circumferential offset from one another, whereby a stepped inclination is advantageously formed. Of course, a rotor core having more than two such rotor core sections connected to one another is also conceivable for this purpose.

The stabilizer actuator advantageously has a gear mechanism arranged in the housing, in particular in the form of a multi-stage planetary gear mechanism, which is coupled to the rotor of the permanent magnet motor.

It is also advantageous if the rotor core, in particular the rotor core section, is formed from sheet-like steel. The rotor core is thus composed of a plurality of sheet metal extending in the transverse direction and arranged one after the other in the axial direction.

Furthermore, it is advantageous if at least one recess, in particular in the form of a slot, which extends substantially in the axial direction, is formed on the stator. Such slots advantageously help to increase the effective magnetic air gap between the stator and rotor, thereby again at least slightly reducing cogging-causing magnetic interaction between the stator and rotor.

In order to avoid cogging, the coil winding has no iron core, additionally or alternatively, the coil winding is supported by a non-return ring (R ü ckschlussring) on the radial outside, but alternatively, the coil winding can also be formed in a self-supporting manner, thereby cogging can be avoided, because the stabilizer actuator can be configured without a stator slot.

An anti-roll stabilizer for a motor vehicle is also proposed, which has two stabilizer parts which are rotatable relative to one another and a stabilizer actuator for rotating the two stabilizer parts relative to one another. The stabilizer actuator is constructed in accordance with the above description, wherein the mentioned features can be present individually or in any combination.

Drawings

The invention is further elucidated below with the aid of the drawing. Wherein:

fig. 1 shows a schematic representation of an anti-roll stabilizer, with a stabilizer actuator, to rotate the two stabilizer parts of the anti-roll stabilizer relative to each other,

fig. 2 shows a schematic illustration of a stabilizer actuator according to a first embodiment, in which the magnet segments are arranged at the outer periphery of the rotor core,

fig. 3 shows the rotor of the stabilizer actuator shown in fig. 2, which has a continuous inclined portion,

fig. 4 shows another embodiment of a rotor for a stabilizer actuator according to fig. 2, the rotor having a stepped slope,

fig. 5 shows a second embodiment of the stabilizer actuator, in which the magnet segments are integrated into the rotor core,

fig. 6 and 7 show a rotor for a stabilizer actuator according to fig. 5, in which a plurality of rotor core segments rotate relative to one another, and

fig. 8 shows a coil winding for a stabilizer actuator, with a self-supporting winding,

fig. 9 shows a schematic representation of a stabilizer actuator according to a further embodiment, in which a slot running in the axial direction is formed at the stator,

fig. 10 shows a schematic illustration of a stabilizer actuator according to a further embodiment, in which a slot running in the axial direction is formed at the stator.

Detailed Description

Fig. 1 shows a very simplified schematic configuration of an anti-roll stabilizer 1. The anti-roll stabilizer 1 is an active anti-roll stabilizer 1, by means of which a torque can be actively engaged by corresponding actuation. The anti-roll stabilizer 1 is provided for a motor vehicle. The anti-roll stabilizer 1 comprises two

stabilizer parts

2, 3 which are rotatable relative to each other. Furthermore, the anti-roll stabilizer 1 comprises two stabilizer bearings 4, 5, by means of which the anti-roll stabilizer 1, in particular the

respective stabilizer parts

2, 3, are rotatably supported at a structure and/or auxiliary frame, which is not shown here. The two

stabilizer parts

2, 3 are coupled in the region of their free ends to a wheel suspension, not shown here.

The anti-roll stabilizer 1 includes a stabilizer actuator 6. By means of which the two

stabilizer parts

2, 3 can be rotated relative to one another, so that a torque can be actively applied. The stabilizer actuator 6 includes a housing 7. The housing 7 is coupled at one of its two ends to one of the two stabilizer parts 2 in a rotationally fixed manner. The housing 7 can be formed in one piece with the first stabilizer part 2 or can also be connected releasably or permanently to the first stabilizer part. The housing 7 has an opening 8 at the other end, through which the second stabilizer part 3 projects into the housing 7.

The stabilizer actuator 6 comprises a permanent magnet motor 9. Furthermore, the stabilizer actuator 6 has a transmission mechanism 10. The transmission 10 is preferably a multi-stage planetary transmission. The second stabilizer part 3 is preferably connected to a carrier, not shown here, of the transmission 10. A permanent magnet motor 9 is arranged in the interior of the housing 7. The same applies to the transmission 10. The permanent magnet motor 9 is coupled to a transmission 10, so that the torque generated by the permanent magnet motor is transmitted in a switchable manner via the transmission 10 to the second stabilizer part 3. Thereby causing relative rotation between the first and

second stabilizer parts

2, 3.

The permanent magnet motor includes a stator 11 and a rotor 12. The stator 11 is arranged radially outside. The stator is also connected to the housing 10 in a rotationally fixed manner. The rotor 12 is arranged radially inward with respect to the stator 11. Furthermore, the rotor is rotatably supported about a rotational axis l 3. For this purpose, the permanent magnet motor 9 preferably has two bearings, not shown here, by means of which the rotor 12 is rotatably mounted on the support of the permanent magnet motor 9 or directly on the housing 7. The rotor 12 is connected to a gear input shaft 14 of the gear 10. Preferably, the transmission input shaft 14 forms a sun gear of the transmission 10.

Fig. 2 shows a view of the end face of the permanent magnet motor 9 according to the first exemplary embodiment in a greatly simplified illustration. As already mentioned above, the permanent magnet motor 9 comprises a radially inner rotor 12, which is rotatably mounted about a rotational axis 13. Furthermore, the permanent magnet motor 9 comprises a radially outer stator 11. The stator 11 has a plurality of stator slots 15 in the circumferential direction, only one of which is provided with a reference numeral for the sake of clarity. The stator slot 15 extends in the axial direction of the permanent magnet motor 9. Furthermore, the permanent magnet motor 9 comprises coil windings 16. The coil winding 16 forms at least one coil. The coil windings are accommodated in the stator slots 15 distributed over the entire circumference of the stator 11.

As can be seen from fig. 2, the rotor 12 comprises a rotor core 17 and a plurality of magnet segments 18. The magnet segments 18 are supported by the rotor core 17. Furthermore, the magnet segments 18 are distributed over the entire circumference of the rotor core 17. The magnet sections 18 extend in the axial direction of the permanent magnet motor 9. According to the present embodiment, the magnet segments 18 are spaced apart from each other in the circumferential direction. Alternatively, however, it is likewise conceivable for the magnet segments to bear against one another in the circumferential direction. Furthermore, the magnet segments 18 according to fig. 2 are fixed at the outer periphery 19 of the rotor core 17. For this purpose, the magnet segments 18 are each bonded with a radially inner connecting surface 20 to an outer periphery 19 of the rotor core 17.

According to the exemplary embodiment shown in fig. 2, the magnet section 18 is embodied concavely in the current end side view. The magnet section thus has a concave attachment face 20. The respective concave connection surface 20 of the magnet segments 18 corresponds here to the outer circumferential circle of the outer circumference 19 of the rotor core 17. Alternatively, the outer periphery 19 of the rotor core 17 has a bevel according to an embodiment not shown here. Therefore, the rotor core 17 has an n-horn shape. In this case, the connection face 20 of the magnet portion 18 may be of flat design. The flat connection surface 20 of the magnet section 18 can therefore be produced cost-effectively and can be glued to an equally flat inclined surface of the rotor core 17.

Preferably, the rotor core 17 is formed of a thin plate-like steel. Here, the rotor core is composed of a plurality of plies extending in the transverse direction of the rotor 12. They may be coated with an insulating layer, whereby hysteresis effects may be reduced.

Fig. 3 shows the rotor 12 of the permanent magnet motor 9 according to the first embodiment shown in fig. 2. Accordingly, to reduce cogging, the magnet sections 18 each have an inclined portion 21. Due to the inclined portion 21, the magnet segments 18 extend over their entire axial length in the axial direction as well as in the circumferential direction of the rotor 12. Advantageously, the cogging of the permanent magnet motor 9 can thus be reduced. The inclined portion 21 is continuously formed in the embodiment shown in fig. 3. This means that the inclination of the inclined portion 21 runs with a slope over the entire axial length. The magnet sections 18 therefore extend obliquely to the axis of rotation 13. As can be seen from fig. 3, the slope of the continuous slope profile is constant. Therefore, the inclined portion 21 is a straight line. To form the continuous inclined portion 21, the magnet section 18 is provided with a basic shape configured as a parallelogram. Thus, its longitudinal sides extend obliquely to the axis of rotation 13. Alternatively, however, the magnet segments 18 can also be formed rectangularly and, in order to form a continuous inclined section, are rotated relative to the axis of rotation 13 and are therefore fixed at an inclination at the rotor core 17.

Fig. 4 shows an alternative embodiment of a rotor 12 for a permanent magnet motor 9 according to the embodiment shown in fig. 2. Also in this case, the magnet section 18 of the rotor 12 has an inclined portion 21. Due to the inclined portions 21, the magnet segments 18 extend in the axial direction as well as in the circumferential direction of the rotor 12 with respect to the entire axial length of the respective magnet segments 18. However, unlike the embodiment shown in fig. 3, the inclined portion 21 is formed stepwise. The inclined portion 21 thus has a stepped slope profile extending obliquely to the axis of rotation 13. According to the exemplary embodiment shown in fig. 4, the gradient has a step 22. Alternatively, however, a plurality of such steps 22 can also form a stepped slope. Only in the region of at least one step 22 is the slope of the slope progression. In the region of the magnet portion 18 adjacent to the step, the gradient profile has a slope of zero.

In order to be able to form the stepped inclination 21, the magnet section 18 according to fig. 4 comprises at least two

section parts

23, 24 adjacent to one another in the axial direction. Each of the magnet segments 18 comprises two of the

segment parts

23, 24, wherein more than two segment parts can also form the magnet segment 18. The

segment parts

23, 24 extend only in the axial direction. This means that their extension in the circumferential direction does not change over the length of the rotor 12. Thus, the

segment parts

23, 24 are rectangular. In order to form the stepped inclination 21, two

segment parts

23, 24 adjacent to one another in the axial direction, which together form the respective magnet segment 18, are offset relative to one another in the circumferential direction. They therefore have a circumferential offset 25 which can be described by an angle. The circumferential offset 25 forms a step 22 of the inclined portion 21 having a stepped inclination.

Fig. 5 shows a second exemplary embodiment of a permanent magnet motor 9 for the anti-roll stabilizer 1 shown in fig. 1. In the following description of the alternative permanent magnet motor 9, the same reference numerals are used for the same or at least similar features in terms of its design and/or mode of operation compared to the first embodiment shown in fig. 2. Unless these features are described in detail again, their design and operation will correspond to those of the features already described above.

The fundamental difference between these two embodiments is therefore that the magnet segments 18 are not arranged at the outer periphery 19 of the rotor core 17, but are instead integrated into the outer periphery 19 of the rotor core 17. Thus, the rotor core 17 according to the embodiment shown in fig. 5 comprises a plurality of recesses 26, of which only one is provided with a reference numeral for the sake of clarity. The pockets 26 are distributed in the circumferential direction of the rotor core 17. A magnet section 18 is received in each of the recesses 26.

Fig. 6 and 7 show a rotor 12 for the permanent magnet motor 9 shown in fig. 5 according to the first embodiment. Accordingly, the recess 26 extends only in the axial direction. This means that they are formed substantially rectangularly. Therefore, their dimensions in the circumferential direction do not change in the axial direction of the rotor 12. However, to form a stepped slope, the rotor core 17 includes a plurality of

rotor core sections

27, 28. Here, the rotor core 17 comprises four such

rotor core sections

27, 28, however, for the sake of clarity only two of them are provided with reference numerals. The

rotor core sections

27, 28 rotate relative to each other, in particular in the same rotational direction. Accordingly, the respective magnet segments 18 of the respective

rotor core segments

27, 28 also thereby rotate relative to one another such that they have a circumferential offset 25. Therefore, the rotor 12 shown in fig. 6 and 7 has a stepped inclined portion 21 like the rotor 12 shown in fig. 4. The

rotor core sections

27, 28 may be bonded to each other.

In an embodiment not shown here, the inclined portion 21 may be formed in the stator in addition to the embodiments shown in fig. 3, 4, 6 and 7. Therefore, in order to reduce the cogging, the stator slots 15 may have respective inclined portions 21, respectively, so that the stator slots 15 extend in the axial direction as well as the circumferential direction of the stator 11 over the entire axial length thereof. In this case, the magnet section 18 of the rotor 12 does not have the inclined portion 21.

Fig. 8 shows a coil winding 16 for avoiding cogging. It may be used in place of the above embodiments. Accordingly, the coil winding 16 is constructed ironless. According to the exemplary embodiment shown here in fig. 8, the coil winding 16 has a self-supporting winding. Therefore, the coil winding 16 according to the embodiment shown here in fig. 8 does not require a support element, such as the stator 11 mentioned in the above embodiments. Alternatively, however, the coil winding 16 can also be supported by a radially outer check ring in an embodiment not shown here.

Fig. 9 shows an end-side view of a permanent magnet motor 9 according to a further embodiment in a greatly simplified illustration. The permanent magnet motor 9 in turn comprises a radially inner rotor 12, which is rotatably supported about a rotational axis 13. Furthermore, the permanent magnet motor 9 comprises a radially outer stator 11. The stator 11 has a plurality of stator slots 15 in the circumferential direction, only one of which is provided with a reference numeral for the sake of clarity. The stator slot 15 extends in the axial direction of the permanent magnet motor 9. Furthermore, the permanent magnet motor 9 comprises coil windings 16. The coil winding 16 forms at least one coil. The coil windings are accommodated in the stator slots 15 distributed over the entire circumference of the stator 11.

As can be seen from fig. 9, the rotor 12 comprises a rotor core 17 and a plurality of magnet segments 18. The magnet segments 18 are supported by the rotor core 17. Furthermore, the magnet segments 18 are distributed over the entire circumference of the rotor core 17. The magnet sections 18 extend in the axial direction of the permanent magnet motor 9. Recesses in the form of slots 29 are formed for each coil winding 16 at the stator 11, which recesses extend substantially in the axial direction. The slots 29 help to enlarge the effective magnetic air gap between the stator 11 and the rotor 12, thereby reducing cogging induced magnetic interactions between the stator 11 and the rotor 12.

Fig. 10 shows a permanent magnet motor 9 which is similar in many respects to the permanent magnet motor explained with the aid of fig. 9. Therefore, to avoid repetition, reference is made to the explanations made therein. In contrast, each coil winding 16 of the permanent magnet motor according to fig. 10 has two slots 29, which extend substantially in the axial direction. By the presence of two notches, the above-mentioned cogging reduction effect is again enhanced.

The invention is not limited to the embodiments shown and described. It is also possible to vary within the scope of the claims, for example combinations of features, even if these features are shown and described in different embodiments.

List of reference numerals

1 anti-roll stabilizer

2 first stabilizer Member

3 second stabilizer Member

4 first stabilizer bearing

5 second stabilizer bearing

6 stabilizer actuator

7 casing

8 opening

9 permanent magnet motor

10 drive mechanism

11 stator

12 rotor

13 axis of rotation

14 transmission mechanism input shaft

15 stator slot

16 coil winding

17 rotor core

18 magnet segment

19 outer periphery of the container

20 connecting surface

21 inclined part

22 steps

23 first segment component

24 second segment component

25 circumferentially offset

26 recess

27 first rotor core section

28 second rotor core section

29 slot

Claims

1. A stabilizer actuator (6) for relative rotation of two stabilizer parts (2, 3) of an anti-roll stabilizer (1), having a housing (7) and a permanent magnet motor (9) arranged therein for torque introduction, which permanent magnet motor comprises a stator (11) which is connected to the housing (7) in a rotationally fixed manner and a rotor (12) which is mounted rotatably relative thereto about a rotational axis (13), wherein the stator (11) has a plurality of stator slots (15) which extend in an axial direction and accommodate coil windings (16) in a circumferential direction, and wherein the rotor (12) has a plurality of magnet segments (18) which extend in an axial direction and are supported by a rotor core (17) in a circumferential direction, characterized in that the stator slots (15) or the magnet segments (18) each have an inclination (21), in order to reduce cogging, the stator slots (15) or the magnet segments (18) extend over their entire axial length in the axial and circumferential direction of the stator (11) and/or rotor (12).

2. The stabilizer actuator according to the preceding claim, characterized in that the inclined portion (21) is formed continuously such that it has a continuous slope course running obliquely with respect to the axis of rotation (13).

3. A stabilizer actuator according to claim 2, characterized in that the slope of the continuous slope course is constant.

4. A stabilizer actuator according to one or more of the preceding claims 2-3, characterized in that, in order to form a continuous inclined portion (21), the magnet segments (18) are arranged obliquely with respect to the axis of rotation (13) at the rotor core (17) or have a basic shape configured as a parallelogram.

5. The stabilizer actuator according to claim 1, characterized in that the inclined portion (21) is formed in a stepped manner, so that it has a stepped slope course running obliquely to the axis of rotation (13) and has at least one step (22).

6. A stabilizer actuator according to claim 5, characterized in that, in order to form the stepped inclination (21), the magnet segments (18) each comprise at least two segment parts (23, 24) adjacent to one another in the axial direction, which have a circumferential offset (25) from one another.

7. A stabilizer actuator according to any one of the preceding claims 1 to 6, characterized in that the magnet segments (18) abut against each other or are spaced apart from each other in the circumferential direction.

8. A stabilizer actuator according to any one of the preceding claims 1 to 7, characterized in that the magnet segments (18) are respectively fixed at the outer periphery (19) of the rotor core (17), in particular adhesively bonded thereto, by means of radially inwardly directed connection faces (20).

9. A stabilizer actuator according to claim 8, characterized in that the connection face (20) of the magnet segment (18) is configured flat and the outer periphery (19) of the rotor core (17) has a bevel corresponding to the flat connection face (20).

10. A stabilizer actuator according to claim 8 above, characterized in that the connection face (20) of the magnet segment (18) is concave in an end side view, so that it corresponds to the outer peripheral curve of the rotor core (17).

11. A stabilizer actuator according to any one of the preceding claims 1 to 7, characterized in that the rotor core (17) has in the circumferential direction a plurality of axially and/or circumferentially extending recesses (26) in which the magnet segments (18) are accommodated.

12. A stabilizer actuator according to any one of the preceding claims 5 to 11, characterized in that, in order to form the stepped inclination (21), the rotor core (17) comprises at least two rotor core sections (27, 28) adjacent to each other in the axial direction, which are rotated relative to each other such that the magnet sections (18) of the rotor core sections (27, 28) have a circumferential offset (25) from each other.

13. The stabilizer actuator according to one or more of the preceding claims 1 to 12, characterized in that the stabilizer actuator (6) has a transmission (10) arranged in the housing (7), in particular in the form of a multi-stage planetary transmission, which is coupled to the rotor (12) of the permanent magnet motor (9).

14. A stabilizer actuator according to one or more of the preceding claims 1-13, characterized in that at least one recess (29) running substantially in the axial direction, in particular in the form of a slot, is configured at the stator (11).

15. A stabilizer actuator (6) for relative rotation of two stabilizer parts (2, 3) of an anti-roll stabilizer (1), the stabilizer actuator has a housing (7) and a permanent magnet motor (9) arranged in the housing, for introducing torque, comprising a coil winding (16) which is connected to the housing (7) in a rotationally fixed manner and a rotor (12) which is mounted in a rotationally fixed manner relative to the coil winding about a rotational axis (13), wherein the rotor (12) has a plurality of magnet segments (18) extending in the axial direction and supported by a rotor core (17) in the circumferential direction, characterized in that the coil winding (16) is designed without an iron core in order to avoid cogging, and/or radially outside the coil winding by a check ring or with a self-supporting winding.

16. An anti-roll stabilizer (1) for a motor vehicle, having two stabilizer parts (2, 3) which can be rotated relative to one another and a stabilizer actuator (6) for rotating the two stabilizer parts (2, 3) relative to one another, characterized in that the stabilizer actuator (6) is constructed according to any one of the preceding claims 1 to 15.