EP2871342B1 - Assembly of an electroacoustic actor in a vehicle structure - Google Patents

Description

The present invention relates to an arrangement of an electroacoustic actuator on a vehicle body of a motor vehicle, according to the preamble of claim 1.

An electroacoustic actuator usually comprises a housing, in which at least one loudspeaker is arranged, which separates a pre-volume from a back volume in the housing. Furthermore, the actuator may have a sound outlet tube, which projects outward from the housing and which is fluidically coupled to the pre-volume.

Such an electro-acoustic actuator can be used in an exhaust system as an active muffler to reduce by means of counter-noise disturbing amplitudes in the transported in the exhaust system noise. Furthermore, such an actuator can also be used to selectively generate or amplify certain frequencies in order to operate a so-called sound design. Likewise, mixed applications are conceivable in which the respective actuator attenuates or reduces interfering frequencies by means of anti-sound while at the same time generating or amplifying desired frequencies.

For the use of such an actuator, it is in principle possible to fix the sound outlet tube directly to an exhaust pipe of the exhaust system to be able to initiate the generated by means of the actuator sound waves directly into the exhaust gas stream. Furthermore, the actuator can be elastically connected to a vehicle body via its housing, so that the actuator can oscillate together with the exhaust system relative to the vehicle body. Due to cramped installation situations, it is often not possible to fix the actuator via the sound outlet tube directly to the exhaust system. In these cases it is In principle, it is possible to fix the actuator as a whole on the vehicle body and to arrange the sound outlet tube free-standing in the environment. Alternatively, it is also conceivable to connect the sound outlet tube via an elastic connecting piece with an exhaust pipe in order to arrange the housing of the actuator at another, more suitable place.

In cases where the housing via the sound outlet tube has no rigid or rigid coupling with an exhaust pipe, there is a risk that the housing is set in vibration during operation of the actuator. In a fixed connection of the housing to the vehicle body thereby the vehicle body can be locally excited to vibrate, which can lead to unwanted noise in the vehicle. The vibration excitation of the housing can be attributed to the fact that the speaker with its cage is ultimately supported on the housing. The cage, on the one hand, tensions a diaphragm of the loudspeaker and, on the other hand, carries an electromagnetic driver, which is drive-connected to the diaphragm. Any vibration introduced into the membrane by the driver acts as an "action" whose "response" from the driver must be supported by the cage to the housing.

A generic arrangement of an electro-acoustic actuator to a vehicle body, for example, from US 2002/047074 A1 known. In the known arrangement, holding devices are used whose holding directions are different and each inclined with respect to an excitation direction of the loudspeaker.

From the US 6,005,957 A In contrast, an arrangement of an electro-acoustic actuator to a vehicle body is known in which the holding devices are designed to be relatively stiff.

From the GB 2 461 284 A an arrangement of a muffler on a vehicle body is known, are used in the holding devices with different holding directions, wherein the respective holding device in its holding direction is resilient and transversely designed to stiff.

The present invention addresses the problem of providing for the arrangement of an actuator on a vehicle body an improved embodiment, which is characterized in particular by a reduced vibration transmission between the actuator and vehicle body.

This problem is solved according to the invention by the subject matter of the independent claim. Advantageous embodiments are the subject of the dependent claims.

The invention is based on the general idea to hold the actuator by means of several separate holding devices on the vehicle body, said holding means are spaced from each other in a circumferential direction of the housing and distributed to the housing. The holding devices are further designed to be elastic in a holding direction, while they are designed to be stiff transversely to the holding direction. The terms "elastic" and "stiff" are to be understood relative to each other, such that the respective holding device in the holding direction has a greater elasticity than transversely thereto. Likewise, the respective holding device has a greater rigidity transverse to the holding direction than parallel to the holding direction. Accordingly, the holding device may also have a certain elasticity transversely to the holding direction, which, however, is significantly smaller than parallel to the holding direction. For example, the elasticity of the respective holding device is at least one order of magnitude larger than transversely to the holding direction parallel to the holding direction.

Due to the elastic holding devices in the holding direction vibrations of the housing in the holding direction are not or only greatly reduced transferred to the vehicle body. By the rigidity of the holding directions transversely to the holding direction, however, a sufficient fixation of the actuator is realized on the vehicle body. The risk of unwanted structure-borne sound transmission from the actuator to the vehicle body can thus be significantly reduced.

According to the invention, the holding directions of the individual holding directions run parallel to one another. As a result, the entire housing or the entire actuator essentially has only the holding direction as a degree of freedom for relative movements with respect to the vehicle body. This improves on the one hand, the vibration decoupling between the vehicle body and actuator parallel to the holding direction, while at the same time transverse to the fixation of the actuator is reinforced to the vehicle body.

According to the invention, it is further provided that the holding directions of the holding devices extend parallel to an excitation direction of the loudspeaker, in which the loudspeaker transmits excitation forces to the housing during operation of the actuator. The excitation direction of the loudspeaker essentially corresponds to the stroke direction or direction of vibration of a loudspeaker diaphragm, the excitation forces counteracting the forces required for deflecting the loudspeaker diaphragm, which results from the physical principle "action equal to reaction". Due to the parallel alignment of the holding directions to said excitation direction, the vibrations generated by the loudspeaker in the housing can be selectively damped.

According to another embodiment, the respective holding device may have a fixedly connected to the housing console, which is connected via a coupling device in the holding direction elastic and transversely rigid with the vehicle body. In other words, the respective holding device has a rigid or rigid or rigidly connected to the housing console, so that the elastic suspension ultimately follows via a coupling device which acts between the respective console and the vehicle body. The use of such consoles facilitates the connection of the holding devices on the housing.

According to another embodiment, the holding devices or the consoles may define a holding plane which extends perpendicular to the excitation direction of the loudspeaker. Preferably, it is thus at least three holding devices in order to be able to clearly define said holding plane. With the help of three or more holding devices, the housing can be securely supported on the vehicle body.

Preferably, the holding directions of the holding devices are aligned perpendicular to the holding plane, so that the support of the housing is torque-free with respect to the vibrations.

In another embodiment, the holding devices or the brackets can be arranged equidistant from a force introduction point of the loudspeaker, from which the loudspeaker transmits dynamic excitation forces to the housing during operation of the actuator. This measure also means that the holding devices ultimately do not have to support torques. The term "equidistant" is to be understood in the present context that preferably equal distances present, but in principle small deviations of not more than 10% in terms of distances of the holding devices from the force introduction point are tolerable and can still be considered as equidistant.

The holding devices or the consoles can be arranged equidistant to a center of mass of the actuator according to another embodiment. This measure has the consequence that even static forces, namely the weight of the actuator transmit no moment between the actuator and vehicle body. Again, the term "equidistant" is to be understood that identical distances are desired, but deviations of a maximum of 10% are tolerable.

In another embodiment, it can be provided that a center of gravity of the actuator and a force introduction point, from which the loudspeaker transmits dynamic excitation forces to the housing during operation of the actuator, are arranged one above the other substantially one inside the other or in the direction of gravity. This measure ultimately leads to the generation of torques in the housing being reduced during the operation of the actuator.

In another embodiment, it may be provided to arrange the loudspeaker in the housing such that an excitation direction of the loudspeaker, in which the loudspeaker transmits excitation forces to the housing during operation of the actuator, runs parallel to the direction of gravity. By this measure, a resulting excitation force of the loudspeaker essentially passes through the center of mass of the actuator. Since thus the excitation force and gravity coaxial, the realization of a torque-free mounting of the housing on the vehicle body simplifies.

In another advantageous embodiment, it can be provided that a coupling device of the respective holding device, which connects a console of the respective holding device fixedly connected to the housing with the vehicle body, is designed as an elastomeric bearing, which is designed to be elastic and transversely rigid in the holding direction. The use of elastomeric bearings, which have a direction-dependent elasticity, on the one hand allows for sufficient vibration damping and on the other hand, a sufficient support for the actuator on the vehicle body.

According to a specific development, the elastomeric bearing may have a first, in particular annular, elastomer region, which supports the console in the holding direction on the vehicle body, wherein the elastomeric bearing also has a second, in particular annular elastomer region, the console in the holding direction on a side facing away from the vehicle body side supported on a disc. Said disc can now be firmly connected by means of a screw which extends through the two Elastomerbereiche and through the console, with the vehicle body. Such an elastomeric bearing has a relatively high elasticity in the holding direction, while at the same time has a comparatively high rigidity transverse to the holding direction.

In a further development, the screw can also extend through a spacer sleeve, which supports the disc in the holding direction on the vehicle body. With the help of such a spacer sleeve, high holding forces between elastomer bearing and vehicle body can be realized, at the same time a predefined bias for the Elastomerbereiche can be realized.

The two elastomer regions can be integrally formed in a common elastomer body. Furthermore, it is conceivable to realize the two elastomer regions by means of separate or separate elastomer bodies.

In another embodiment, said coupling means may comprise an elastomeric body, on the one hand firmly connected to the respective console and on the other hand firmly connected to a holder attached to the vehicle body, wherein the elastomeric body in the holding direction is designed to be elastic and transverse thereto rigid. This embodiment is particularly simple and therefore inexpensive. For example, the elastomeric body may be designed in the manner of a rubber loop, in which on the one hand the console and on the other hand the respective holder can be inserted. The respective console can be made more or less wire-shaped according to a preferred variant. Additionally or alternatively, the respective holder may be designed more or less wire-shaped.

In another embodiment, the respective coupling device may comprise at least one elastomeric body and / or at least one spring element and have a linear guide which defines the holding direction. In this case, the functions of the elastic support in the holding direction and the stiff transverse support on two different components of the coupling device divided up. The elastic holding force transmission takes place via the elastomer body or via the spring element, while the stiff transverse support is effected via the linear guide.

According to another advantageous embodiment, it can be provided that the actuator is held exclusively via the holding device in a vehicle body. In particular, there is no holding force transmission between the sound outlet tube and the vehicle body or an exhaust system. Additionally or alternatively, it may be provided that the sound outlet tube is arranged free-standing in an environment of the actuator. In this case, any connection of the sound outlet tube is missing, for example, to an exhaust system.

Finally, the present invention thus also relates to a vehicle having a vehicle body and at least one actuator, which is arranged on the vehicle body by means of an arrangement of the type described above.

Other important features and advantages of the invention will become apparent from the dependent claims, from the drawings and from the associated figure description with reference to the drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the respectively indicated combination but also in other combinations or alone.

Preferred embodiments of the invention are illustrated in the drawings and will be described in more detail in the following description, wherein like reference numerals refer to the same or similar or functionally identical components.

Fig. 1

eine stark vereinfachte Schnittansicht einer Anordnung eines Aktors an einem Fahrzeugaufbau,

Fig. 2

eine isometrische Ansicht der Anordnung,

Fig. 3

eine vereinfachte Schnittansicht durch eine Halteeinrichtung der Anordnung aus Fig. 2,

Fig. 4

eine stark vereinfachte isometrische Ansicht der Anordnung, jedoch bei einer anderen Ausführungsform,

Fig. 5

eine vergrößerte Ansicht einer Kopplungseinrichtung der in Fig. 4 verwendeten Halteeinrichtung,

Fig. 6

eine Schnittansicht der Kopplungseinrichtung gemäß Schnittlinien VI in Fig. 5,

Fig. 7

eine Schnittansicht einer Halteeinrichtung bei einer weiteren Ausführungsform.

Show, in each case schematically,

Fig. 1

a highly simplified sectional view of an arrangement of an actuator on a vehicle body,

Fig. 2

an isometric view of the arrangement,

Fig. 3

a simplified sectional view through a holding device of the arrangement Fig. 2 .

Fig. 4

a greatly simplified isometric view of the arrangement, but in another embodiment,

Fig. 5

an enlarged view of a coupling device of in Fig. 4 used holding device,

Fig. 6

a sectional view of the coupling device according to section lines VI in Fig. 5 .

Fig. 7

a sectional view of a holding device in a further embodiment.

The FIGS. 1, 2 and 4 each show an arrangement 1 of an electro-acoustic actuator 2 on a vehicle only partially or partially illustrated structure 3 of a motor vehicle, not otherwise shown. The actuator 2 has a housing 4 and a sound outlet tube 5, which protrudes from the housing 4 to the outside in an environment 6 of the actuator 2.

Corresponding FIG. 1 is arranged in the housing 4, at least one speaker 7, which separates a Vorvolumen 8 from a rear volume 9 in the housing 4. In the illustrated preferred example, the actuator 2 has only one loudspeaker 7. The loudspeaker 7 has in a conventional manner a diaphragm 10 and an electromagnetic driver 11 for driving the diaphragm 10. Driver 11 and diaphragm 10 are drivingly connected in the manner shown.

Further, a cage 12 is provided, on the one hand carries the driver 11 and on the other hand, the membrane 10 spans. The cage 12 also serves to attach the speaker 7 to the housing 4. For this purpose, a circulation 13 of the cage 12 is inserted into a flange 14, via the two housing shells, namely a lower housing shell 15 and an upper housing shell 16 of the housing 4 are fastened together. The cage 12 is permeable to the rear volume 9, so that the rear volume 9 extends through the cage 12 as far as a rear side of the membrane 10 facing the upper housing shell 16. In the case 4, in the embodiment shown here, a funnel 17 is also arranged, which encloses the pre-volume 8 and which connects a front volume 8 facing the pre-volume 8 fluidically or acoustically with the sound exit tube 5. In other words, the sound outlet tube 5 is fluidically coupled to the pre-volume 8. In this way, sound generated by means of the diaphragm 10 can be radiated via the hopper 17 into the sound outlet pipe 5 and through the sound outlet pipe 5 into the environment 6. In the example of FIG. 1 separates the funnel 17 in the lower housing shell 15, the pre-volume 8 also from an additional volume 18. Suitably, the circulation 13 is acoustically permeable, for example by means of corresponding openings or openings. In this way, the additional volume 18 can be acoustically added to the rear volume 9, whereby the actuator 2 has a particularly large back volume (9 + 18).

The actuator 2 may be designed as an active muffler or as a sound generator or as a combination of active muffler and sound generator to make a sound emission of the vehicle. If the vehicle is equipped with an internal combustion engine, with the designed as an active muffler actuator 2, a noise emission in the environment of the vehicle can be reduced. For vehicles with smaller internal combustion engines and / or vehicles with electric drive, it is possible to use the actuator 2 to selectively generate a sound emission for the vehicle. Of importance is an acoustic feedback for the driver to get as in a conventional vehicle, a sense of the current performance of the drive. Not inconsiderable just in electric vehicles, the associated with a corresponding acoustic emission improved passive vehicle safety, since the vehicle can be better perceived by other road users. Because with electric vehicles, the driving noise is reduced at low vehicle speeds mainly on the rolling noise, so there is a risk that an electric vehicle is overheard by a pedestrian or cyclist.

According to the FIGS. 1, 2 and 4 the actuator 2 is held by means of a plurality of holding devices 19 on the vehicle body 3. The holding devices 19 are in one in the Figures 2 and 4 arranged by a double arrow indicated circumferential direction 20 of the housing 4, so that they are spaced apart in the circumferential direction 20. Preferred is a variant in which exactly three such holding devices 19 are provided. In principle, however, more than three holding devices 19 may be provided. Theoretically, a solution with only two holding devices 19 is conceivable.

The holding devices 19 are each attached to the housing 4, and preferably to the lower housing shell 15. The holding devices 19 are each in one in the FIGS. 1 . 3 and 5-7 indicated by a double arrow mounting direction 21 elastically and transversely to the holding direction 21 designed comparatively stiff. Preferably, the holding directions 21 of all holding devices 19 extend parallel to one another. Furthermore, the holding directions 21 preferably run parallel to one in FIG FIG. 1 In the excitation direction 22, the loudspeaker 7 transmits excitation forces to the housing 4 during the operation of the actuator 2. It is also possible FIG. 1 can be seen that the holding means 19 according to a preferred embodiment define a holding plane 23. In other words, the holding devices 19 lie in a common holding plane 23. The holding plane 23 now extends perpendicular to the excitation direction 22 of the loudspeaker 7. Thus, the holding directions 21 are also perpendicular to the holding plane 23.

According to the Figures 1-7 the respective holding device 19 has a bracket 24 which is fixedly connected to the housing 4, and a coupling device 25, by means of which the respective bracket 24 in the holding direction 21 is elastically and transversely relatively rigidly connected to the vehicle body 3. According to FIG. 1 can now be said consoles 24 and the holding means 19 are arranged on the housing 4 equidistant to a force introduction point 26 of the speaker 7, from which the speaker 7 in the operation of the actuator 2 dynamic excitation forces on the housing 4 transmits. The force introduction point 26 is located here in the driver 11, in which the reaction when exciting the membrane 10 (action) is formed. These excitation forces are now transmitted by the driver 11 via the cage 12 and the circulation 13 in the housing 4.

Furthermore, it is provided here that the holding devices 19 or their brackets 24 are arranged on the housing 4 equidistant to a center of mass 27 of the actuator 2. In the arrangement 1, this center of mass 27 and the aforementioned force introduction point 26 in the direction of gravity arranged one above the other. In addition, the arrangement of the speaker 7 in the housing 4 is preferably such that the excitation direction 22 is parallel to the direction of gravity. Furthermore, the arrangement of the loudspeaker 7 in the housing 4 preferably takes place such that a resultant excitation force, which passes through the force introduction point 26, also passes through the center of mass 27. Thus, the excitation forces and the gravity act uniformly on the actuator 2, whereby in particular a torque formation within the actuator 2 can be avoided.

In the FIGS. 1, 2 and 4 In addition, an electrical connection 28 is indicated, by means of which an electrical wiring 29 can be connected through the housing 4 to the loudspeaker 7 or to the driver 11. Furthermore, a connection of further electrical or electronic components of the actuator 2 can take place via the wiring 29, for example a microphone or a temperature sensor.

With reference to the Figures 3-7 Specific embodiments of the holding devices 19 will be explained in more detail below. It shows FIG. 3 a possible embodiment of the holding device 19, as in the in FIG. 2 shown embodiment of the arrangement 1 can be used. The FIGS. 5 and 6 show a coupling device 25, as used in the holding device 19 of the embodiment shown in Figure 4. FIG. 7 shows a holding device 19 according to another embodiment.

At the in FIG. 3 In the embodiment shown, the coupling device 25 of the holding device 19 is designed as an elastomer bearing 30, which has an annular first elastomer region 31 and an annular second elastomer region 32. The first elastomeric region 31 supports the bracket 24 in the holding direction 21 on the vehicle body 3 from. The second elastomer region 32 supports the bracket 24 in the holding direction 21 on a disc 33, which is arranged on a side facing away from the vehicle body 3 side of the bracket 24. The disc 33 is firmly connected by means of a screw 34 to the vehicle body 3. For this purpose, the screw 34 extends through the two Elastomerbereiche 31, 32 and through the console 24 therethrough. In the example, the screw 34 also extends through a spacer sleeve 35 through which the disc 33 is supported in the mounting direction 21 on the vehicle body 3. The screw 34 has in the example a screw 36 and a nut 37. A screw head 38 of the screw 36 is supported on the disc 33 from. A screw shank 39 of the screw 36 extends through the disc 33, through the spacer sleeve 35 and thus through the two elastomeric bodies 31 and 32 and through the bracket 24 and through a connection region 40 of the vehicle body 3. The nut 37 is screwed to the screw shaft 39 and is supported by a washer 41 on a side facing away from the console 24 side on the connection portion 40 of the vehicle body 3 from. In the example of FIG. 3 The two elastomer regions 31 and 32 are separate elastomer bodies. In principle, however, an embodiment is also conceivable in which the two elastomer regions 31, 32 are integrally formed on a common elastomer body, that is, of the same material. By way of example, the two elastomer regions 31, 32 can communicate with one another via a section likewise passed through the bracket 24.

In the in the Figures 4-6 In the embodiment shown, the coupling device comprises an elastomeric body 42, which is configured here as a rubber loop. The elastomeric body 42 is on the one hand firmly connected to the respective console 24 and thus via the console 24 to the housing 4. On the other hand, the elastomeric body 42 is fixedly connected to a holder 43, which in turn on Vehicle body 3 is attached. In that regard, the respective elastomeric body 42 is connected via the respective holder 43 fixed to the vehicle body 3. The respective elastomer body 42 is designed so that it is designed to be relatively stiff in the holding direction 41 elastic and transversely thereto. This is achieved for example by means of corresponding area moments of inertia in conjunction with recesses 44, which are in the FIGS. 5 and 6 are recognizable.

Finally shows FIG. 7 a further embodiment of the holding device 19, in which the coupling device 25 has at least one elastomer body 45 or at least one spring element 46 has. In principle, an embodiment is conceivable in which both at least one elastomer body 45 and at least one spring element 46 are provided. Furthermore, the coupling device 25 here comprises a linear guide 47, which is formed in the example shown by a pin 48 and a socket 49, in which the pin 48 is arranged bidirectionally adjustable. The linear guide 47 thus defines the holding direction 21 and stabilizes the coupling device 25 transversely to the holding direction 21. In contrast, the elastomer body 45 and the spring element 46 generates the elasticity of the coupling device 25 parallel to the holding direction 21 in the example FIG. 7 the pin 48 is fixedly connected to the console 24, while the socket 49 is fixedly connected to the vehicle body 3.

According to the in the FIGS. 1, 2 and 4 In the case of the embodiments shown, the actuator 2 is preferably held exclusively by the holding devices 19 on the vehicle body 3. As a result, therefore, no holding forces can be transmitted to the housing 4, in particular via the sound outlet tube 5. In the examples shown, the sound outlet tube 5 is arranged free-standing in the environment 6 of the actuator 2, that is, it has no contact with other components of the vehicle.

Claims (12)

1. Arrangement of an electroacoustic actuator (2) on a vehicle body (3) of a motor vehicle,

   - wherein the actuator (2) comprises a housing (4) in which at least one speaker (7) is arranged, which separates a front volume (8) from a rear volume (9) in the housing (4),

   - wherein the actuator (2) is held on the vehicle body (3) by a plurality of retaining devices (19), which are arranged on the housing (4) spaced apart in a circumferential direction (20) of the housing (4) and each designed to be spring-elastic in the retaining direction (21) and rigid in the direction transverse thereto,

   characterised in that

   - the actuator (2) comprises a sound outlet tube (5) which protrudes outwards from the housing (4) and is fluidically coupled with the front volume (8),

   - and in that the retaining directions (21) of the retaining devices (19) lie parallel to an excitation direction (22) of the speaker (7), in which direction the speaker (7) during operation of the actuator (2) transfers excitation forces onto the housing (4).
2. Arrangement according to claim 1,
   characterised in that
   each retaining device (19) comprises a bracket (24) rigidly connected to the housing (4), which is connected with the vehicle body (3) via a coupling device (25) elastically in the retaining direction (21) and rigidly transverse thereto.
3. Arrangement according to claim 2,
   characterised in that
   each coupling device (25) is designed as an elastomer bearing (30).
4. Arrangement according to claim 3,
   characterised in that

   - the elastomer bearing (30) comprises a first elastomer region (31), which braces the bracket (24) against the vehicle body (3) in the retaining direction (21),

   - in that the elastomer bearing (30) comprises a second elastomer region (32), which braces the bracket (24) in the retaining direction (21) against a washer (33), on a side facing away from the vehicle body (3),

   - and in that the washer (33) is rigidly connected with the vehicle body (3) by means of a screw connection (34) which extends through both the elastomer regions (31, 32) and the bracket (24).
5. Arrangement according to claim 2,
   characterised in that
   each coupling device (25) comprises an elastomer body (42), which is connected on the one hand rigidly with the respective bracket (24) and on the other hand rigidly with a retainer (43) fastened on the vehicle body (3), wherein the elastomer body (42) is designed to be elastic in the retaining direction (21) and rigid transverse thereto.
6. Arrangement according to claim 2,
   characterised in that
   the coupling device (25) comprises at least one elastomer body (45) and/or at least one spring element (46) and at least one linear guide (47) defining the retaining direction (21).
7. Arrangement according to one of claims 1 to 6,
   characterised in that
   the retaining devices (19) or the brackets (24) define a retaining plane (23) which extends perpendicular to the excitation direction (22) of the speaker (7).
8. Arrangement according to one of claims 1 to 7,
   characterised in that
   the retaining devices (19) or the brackets (24) are arranged equidistant from a force introduction point (26) of the speaker (7), from which excitation forces from the speaker (7) are transferred onto the housing (4) during operation of the actuator (2).
9. Arrangement according to one of claims 1 to 8,
   characterised in that
   the retaining devices (19) or the brackets (24) are arranged equidistant from a centre of gravity (27) of the actuator (2).
10. Arrangement according to one of claims 1 to 9,
    characterised in that
    a centre of gravity (27) of the actuator (2) and a force introduction point (26), from which excitation forces from the speaker (7) during operation of the actuator (2) are transferred onto the housing (4), are arranged substantially one in the other or one above the other in the direction of gravitational force.
11. Arrangement according to one of claims 1 to 10,
    characterised in that
    the speaker (7) is arranged in the housing (4) such that the excitation direction (22) of the speaker (7), in which the speaker (7) transfers excitation forces onto the housing (4) during operation of the actuator (2), lies parallel to the direction of gravitational force.
12. Arrangement according to one of claims 1 or 11,
    characterised in that

    - the actuator (2) is only retained on the vehicle body (3) via the retaining devices (19),

    - and in that the sound outlet tube (5) is arranged to be free-standing in an environment (6) of the actuator (2).

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