Sounding unit of acoustic vehicle alarm system and acoustic vehicle alarm system

Abstract

The proposed solution relates to a sound generating unit of an acoustic vehicle alarm system for generating sound that can be heard by a person located in the surroundings of a vehicle, and to an acoustic vehicle alarm system. The sound-generating unit (1) has a housing (10) with a housing wall which at least partially delimits an outer side of the housing (10) and which is designed with a vibratable diaphragm (101) for generating sound. A vibration exciter (2) for making the sound generating unit (1) generate sound is arranged on the inner side of the diaphragm (101).

Description

TECHNICAL FIELD

[0001] The proposed solution relates to a sound-emitting unit of an acoustic vehicle alerting system (AVAS). BACKGROUND

[0002] Acoustic vehicle alerting systems are used, for example, in electric vehicles. Here, a sound is to be generated via one or more loudspeaker units that can be heard by persons located in the surroundings of the vehicle, in particular pedestrians, which sound (or more precisely its frequency) varies depending on the vehicle speed in order to acoustically draw the attention of people to the moving vehicle. When the vehicle is moving at a driving speed below a threshold value, for example at a level of 20 km / h or 30 km / h, a sound is output via the loudspeaker of the loudspeaker unit at this time which is audible and varies in its frequency. The respective loudspeaker unit must therefore be located in an outer region of the vehicle so that the sound generated thereby can be clearly heard by persons located in the surroundings of the vehicle. However, this also places particular demands on the design of the loudspeaker housing in order to protect the loudspeaker accommodated within the loudspeaker housing, in particular, from environmental influences.

[0003] In loudspeaker units that have been common hitherto, at least one loudspeaker is fixed in the housing by means of adhesive bonding, screwing or snap connections. Assembling the loudspeaker into the respective housing can therefore be both cumbersome and cost-intensive. Furthermore, in view of the installation of the loudspeaker unit in the outer region, it can only be achieved with considerable outlay to ensure the tightness of the housing, for example to achieve a protection class of IP69. UTILITY MODEL CONTENT

[0004] The task of the proposed solution is therefore, in this context, to provide a feasible solution for sound-emitting in a vehicle alerting system which is improved in this respect.

[0005] This task is solved with a sound-emitting unit as follows.

[0006] The proposed sound-emitting unit comprises a housing having a housing wall which at least partially delimits an outer side of the housing, the housing wall being configured to have a vibratable diaphragm for sound-emitting, an (electromechanical) exciter of the sound-emitting unit being arranged on an inner side of the diaphragm.

[0007] The housing wall of the proposed housing of the sound-emitting unit thus integrates a membrane which can be vibrated by the exciter for sound generation. The proposed sound-emitting unit thus does not require a loudspeaker for sound emission and can therefore be produced significantly more inexpensively and also with a lighter weight. Furthermore, the interior space of the housing, which accommodates the exciter, can be relatively easily closed off from the surrounding exterior space. The risk of dirt penetrating into the interior space is also low, and the proposed sound-emitting unit can be constructed more compactly than a loudspeaker unit having a loudspeaker located inside.

[0008] The proposed sound-emitting unit is here provided for an acoustic vehicle warning system for generating a sound which can be heard by persons, in particular pedestrians, located in the surroundings of the vehicle. It is possible here with the warning system to change the sound, more precisely its frequency, which can be generated with the sound-emitting unit, in dependence on the vehicle speed in order to acoustically draw the attention of people to a vehicle which is driving. Via the sound emission which changes in dependence on the driving state, and thus the driving speed, of the vehicle, it is thus possible to signal to persons located in the surroundings of the vehicle that a vehicle is approaching or receding.

[0009] As mentioned above, the exciter for the membrane can be accommodated in the (completely closed) interior space of the housing. Control electronics for electronically controlling the exciter can also be arranged in this interior space. For example, the corresponding control electronics of the sound-emitting unit are integrated on a circuit board which is electrically connected to the exciter.

[0010] In order to couple the circuit board to a power supply on the vehicle side and / or to higher-level control electronics on the vehicle side, the sound-emitting unit can have a coupling which is electrically connected to the circuit board and which is accessible from the outside of the housing.

[0011] In one embodiment variant, the membrane of the sound-emitting unit has a plurality of surface structure elements via which the membrane is predestined for a specific natural frequency, and thus a specific frequency behavior, for sound emission. Via the plurality of (at least two) surface structure elements on the membrane integrated into the housing side, it is thus possible to easily design a specific vehicle type in terms of a tonal profile in terms of pitch. For example, via the surface structure on the membrane which can be vibrated, a relatively narrow-band frequency behavior can be easily realized for the vibrations to be generated. Depending on the desired tonal profile, it is possible, for example, to increase the bass component of the emitted sound for a larger or heavier vehicle. In a similar manner, if the sound-emitting unit is to be used in an acoustic vehicle warning system for a relatively light or small vehicle, it is possible to increase the treble component in the tonal profile.

[0012] It can be provided in the case of the use of the surface structure element that the acoustic properties of the sound-emitting diaphragm are already essentially designed by the geometry of the diaphragm, i.e. in particular in terms of the dimensions of the diaphragm and typical parameters such as length, width, height and thickness, and the material from which the diaphragm is made, for a specific sound-emitting behavior before the surface structure element is applied. The refinement of these properties, which have already been essentially adjusted beforehand, is then achieved via the surface structure element.

[0013] In principle, one embodiment variant of the proposed sound-emitting unit is set up for generating sounds in the range from 400 Hz to 4000 Hz. For example, the sound-emitting unit can be designed and set up here for installation in the rear region or in the front region of a vehicle, in particular in the region of the respective bumper.

[0014] In one embodiment variant, the sound-emitting unit additionally has a Helmholtz resonator in the housing. Via this Helmholtz resonator, for example, the amplitude of specific frequency components can be increased. In particular, with the Helmholtz resonator, bass components can be increased without the use of a more powerful electromechanical exciter. For example, for the Helmholtz resonator, a through-opening is provided on the housing which is coordinated with the desired frequency behavior, with which the interior of the housing is in communication with the exterior of the housing. The Helmholtz resonator can be coordinated here in such a way that, at a predetermined coordination frequency, a level increase in the bass frequency range is achieved in order to correspondingly increase the bass frequency components thereby.

[0015] In one embodiment variant, at least one vibratable passive diaphragm is configured on a further housing wall of the housing. Thus, no exciter is provided on the vibratable passive diaphragm. However, like the (main) diaphragm with the exciter, the passive diaphragm also borders the interior of the housing, i.e. with its inner side it adjoins the completely enclosed interior of the housing. Thus, when the (main) diaphragm is excited by the electromechanical exciter, the vibratable passive diaphragm also vibrates as a result of the pressure changes in the interior in order to also emit sound with the vibrating passive diaphragm.

[0016] The at least one passive diaphragm can be set up here precisely for air sound in the bass frequency range. Thus, via the passive diaphragm it can be possible to generate sounds in the frequency range from 50 Hz to 150 Hz.

[0017] In one possible refinement, on opposite housing walls of the housing respectively a vibratable passive membrane is constructed. These passive membranes can then be coordinated with one another in terms of their natural frequency in such a way that, when the (primary) membrane is excited to vibrate by the exciter, the passive membranes can be excited at the same frequency or at a frequency offset from one another by a defined phase shift. The exciter-excited (primary) membrane vibration here results in an increase in the pressure level in the interior space of the housing, which will cause the passive membranes to vibrate.

[0018] In one embodiment variant, the housing additionally also has a pressure compensation membrane for compensating pressure between the interior space of the housing and the surrounding exterior space due to temperature and / or humidity fluctuations. Such a pressure compensation membrane is not provided for sound emission, but can nevertheless be integrated on a housing wall.

[0019] Part of the proposed solution is also an acoustic warning system for a vehicle for increasing a sound that can be heard by persons located in the surroundings of the vehicle, which sound varies depending on the vehicle speed in order to acoustically draw the attention of persons to the moving vehicle. The proposed acoustic warning system here has at least one embodiment variant of the proposed sound-emitting unit. BRIEF DESCRIPTION OF DRAWINGS

[0020] The attached drawings exemplarily illustrate possible embodiment variants of the proposed solution.

[0021] wherein:

[0022] Figure 1 A cutaway view of a first embodiment variant of the proposed sound-emitting unit is shown, which has a vibratable membrane integrated on the housing side;

[0023] Figure 2 A view of an embodiment variant of the proposed sound-emitting unit is shown, which has passive membranes integrated on the housing side, in accordance with Figure 1 DETAILED DESCRIPTION

[0024] Figure 1 A cutaway view of an embodiment variant of the proposed sound-emitting unit 1 is shown. The sound-emitting unit 1 has a fully enclosed housing 10, in the interior space 100 of which, inter alia, an electronic control circuit board 3 is accommodated. The circuit board 3 is connected via at least one connection element 4, for example a connection cable for signal transmission and / or power supply, with an electromechanical exciter 2 located in the interior space 100.

[0025] At present, the exciter 2 is arranged at the inner side of a housing membrane 101, which with its outer side forms part of the outer surface of the housing 10. The housing 10 has a further housing membrane 102 on the opposite side, which with its outer side also forms part of the outer surface of the housing 10. Figure 1 ​The housing wall defining the upper side of the housing 10 thus integrates the vibratable housing membrane 101. The housing membrane 101 can be vibrated electronically via the exciter 2 arranged at its inner side for sound emission.

[0026] Furthermore, the housing membrane 101 has a plurality of surface structure elements 1010 at its outer side via which the natural frequency of the housing membrane 101, and thus the frequency behavior of the housing membrane 101, is adjusted to the desired tonal profile. The tonal profile is here already "roughly" adjusted via the geometry of the housing membrane 101 and the material from which the housing membrane 101 is made, and is refined via the surface structure elements 1010.

[0027] The sound-emitting unit 1 is currently provided for an acoustic vehicle warning system in which the housing membrane 10 is sounded in dependence on the driving state of the vehicle and in particular the driving speed of the vehicle in order to acoustically draw the attention of persons located in the surroundings of the vehicle to an approaching or receding vehicle. In order to control the vibration behavior of the housing membrane 101 via the circuit board 3 in dependence on the driving state of the vehicle, the sound-emitting unit 1 can be connected with a vehicle-side power supply and vehicle-side control electronics. To this end, the housing 10 has an external connection 5 which is accessible at its outer side. This external connection 5 is electrically connected with the circuit board 3. The external connection 5 is realized, for example, via one or more plug connections which are accessible at the outer side of the housing 10.

[0028] Since the housing membrane 101 is part of the housing wall of the housing 10 and thus directly realizes sound emission at the outer side of the housing 10 via the housing element, the completely enclosed interior space 100 of the currently cuboid-shaped housing 10 can be relatively easily sealed against external influences and in particular against the ingress of liquids and dirt. Furthermore, since no loudspeaker needs to be accommodated in the interior space 100, the sound-emitting unit 1 is also relatively light and compact.

[0029] In an improvement not shown in Figure 1 The housing 10 can also integrate a Helmholtz resonator in this.

[0030] In accordance with Figure 2In another possible refinement, passive diaphragms 6a and 6b are additionally provided on opposite side walls of the housing 10. Thus, each passive diaphragm 6a and 6b is integrated on a (here lateral) housing wall of the housing 10 and likewise vibratable. However, no own exciter 2 is provided on the passive diaphragm 6a or 6b. Rather, the passive diaphragms 6a, 6b vibrate due to a change in the pressure level within the interior space 100 when the housing diaphragm 101 is excited. The passive diaphragms 6a and 6b can here be coordinated with one another and with the housing diaphragm 101 in terms of their natural frequency, such that the passive diaphragms 6a and 6b vibrate at the same or almost the same frequency when the housing diaphragm 101 is excited by the exciter 2 in order to sound in the bass frequency range. Thus, the additional passive diaphragms 6a, 6d are provided for air sound transmission in the bass frequency range and thus for sounding in the frequency range of 50 Hz to 150 Hz. Thus, with the passive diaphragms 6a and 6b, an additional bass component in the sounding can be achieved without an additional loudspeaker and also without an additional or more powerful electromechanical exciter 2.

[0031] List of reference signs

[0032] 1 sound unit

[0033] 10 housing

[0034] 100 interior space

[0035] 101 housing diaphragm

[0036] 1010 surface structure element

[0037] 2 exciter

[0038] 3 circuit board

[0039] 4 connection element

[0040] 5 external coupling

[0041] 6a, 6b passive diaphragm

Claims

1. A sound-generating unit for an acoustic vehicle alarm system, wherein the acoustic vehicle alarm system is used to generate a sound that can be heard by persons located in the surrounding environment of the vehicle, wherein, The sound-generating unit (1) includes a housing (10), Its features are, The housing (10) has a housing wall that at least partially defines the outer side of the housing (10), the housing wall being configured to have a vibrating diaphragm (101) for sound generation, on the inner side of the diaphragm being arranged an exciter (2) of the sound generation unit (1).

2. The sound-generating unit according to claim 1, characterized in that, The vibrator (2) is housed in the internal space (100) of the housing (10).

3. The sound-generating unit according to claim 2, characterized in that, At least one circuit board (3) electrically connected to the exciter (2) is housed in the internal space (100).

4. The sound-generating unit according to claim 3, characterized in that, The circuit board (3) is electrically connected to the connection part (5) of the sound-generating unit (1), and the connection part can be accessed from the outside of the housing (10).

5. The sound-generating unit according to any one of claims 1 to 4, characterized in that, The diaphragm (101) has a plurality of surface structure elements (1010) via which the diaphragm (101) is given a specific intrinsic frequency and thus a specific frequency response for sound generation.

6. The sound-generating unit according to any one of claims 1 to 4, characterized in that, The housing (10) has a Helmholtz resonator.

7. The sound-generating unit according to any one of claims 1 to 4, characterized in that, At least one vibrating passive diaphragm (6a, 6b) is constructed on another shell wall of the shell (10).

8. The sound-generating unit according to claim 7, characterized in that, The opposing shell walls of the shell (10) are each provided with at least one vibrating passive diaphragm (6a, 6b), and the passive diaphragms (6a, 6b) are coordinated with each other in terms of their natural frequencies, such that when the diaphragm (101) is excited by the exciter (2) to vibrate, the passive diaphragms (6a, 6b) can be excited at the same frequency or at a frequency that is deviated from each other by a defined phase shift.

9. The sound-generating unit according to claim 7, characterized in that, At least one passive diaphragm (6a, 6b) is configured for airborne sound transmission in the low frequency range.

10. An acoustic vehicle alarm system, said acoustic vehicle alarm system for generating a sound audible to persons in the surrounding environment of a vehicle, said sound varying depending on the speed of said vehicle in order to acoustically attract the attention of persons to a moving vehicle, characterized in that, The acoustic vehicle alarm system has at least one sound-generating unit (1) according to any one of claims 1 to 9.

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