Loudspeaker system for a motor vehicle, method for forming a loudspeaker system, and motor vehicle

Abstract

The present invention relates to a loudspeaker system (1) for a motor vehicle (2), in particular an AVAS loudspeaker system, preferably for a motor vehicle (2), in particular an electric motor vehicle, said loudspeaker system comprising a first housing (10) and a second housing (20), wherein the second housing (20) has an opening (22) for bass reflex tuning. The first and second housings (10, 20) are arranged at least partially against one another. The loudspeaker system (1) has at least two loudspeakers (30), wherein each of the at least two loudspeakers (30) has a voice coil (34) able to move in an axis (L). The at least two loudspeakers (30) are arranged on at least two opposing side surfaces (11, 12) of the first housing (10), wherein at least one of the at least two loudspeakers (30), preferably what is referred to as an internal loudspeaker (90), interacts acoustically with the interior (21) of the second housing (20). Furthermore, it may be advantageous if the axes (L) of these loudspeakers (30) do not run coaxially.

Description

[0001] BME016 1Loudspeaker system for a motor vehicle, method for forming a loudspeaker system, and motor vehicle The invention relates to a loudspeaker system for a motor vehicle, in particular for an electric motor vehicle, having the features of patent claim 1, a method for forming a loudspeaker system having the features of patent claim 19, and a motor vehicle having the features of claim 21. Loudspeaker systems for motor vehicles are already known from the prior art in various designs. For example, in the prior art, generic loudspeaker systems for motor vehicles are also called AVAS loudspeakers or AVAS loudspeaker systems. Originally, the lower noise pollution was considered a unique selling point of electric cars, but their lower exterior noise can pose a danger to pedestrians and cyclists.Therefore, all new electric vehicles sold in the EU and the USA must, under certain conditions, be equipped with acoustic vehicle warning systems (AVAS). Acoustic vehicle warning systems (AVAS) are typically designed as small loudspeaker systems that emit sounds in the required frequency range of 160 to 4000 Hz. When loudspeaker systems are used in vehicles, particularly for sound reinforcement in the exterior of a vehicle, they must be resistant to moisture, splash water, salt, and dust. Sensitive components, such as the voice coil of the loudspeaker, in particular, must be protected from such environmental influences. Therefore, loudspeaker systems with a closed housing are state-of-the-art. BME016 2Patent WO 2020099222 A1 describes a loudspeaker system for a motor vehicle, which has a loudspeaker arranged within a closed housing and radiates into the surrounding area. A disadvantage of previous loudspeaker systems with a closed housing is that, particularly in the low frequency range, a representative acoustic appearance cannot be satisfactorily produced, and loudspeaker systems with a housing in which a bass reflex opening is used to achieve low frequencies are not suitable for outdoor use, since dirt, dust, and moisture could impair the sensitive components of the loudspeaker. The present invention is dedicated to the task of proposing a generic loudspeaker system for motor vehicles that expediently eliminates the disadvantages known from the prior art.The proposed loudspeaker system for motor vehicles should meet high mechanical requirements and high acoustic demands, particularly with regard to volume, frequency range, and distortion. The loudspeaker system should also preferably allow easy adaptation to different vehicles. These objects are achieved by a loudspeaker system for a motor vehicle, in particular for an electric vehicle, having the features of patent claim 1, a method for forming a loudspeaker system having the features of patent claim 20, and a motor vehicle having the features of claim 22. Advantageous embodiments and further developments of the invention are specified in the dependent claims. BME016 3According to the invention, a loudspeaker system for a motor vehicle, in particular an AVAS loudspeaker system, preferably for a motor vehicle, in particular an electric vehicle, is provided, which comprises a first housing and a second housing, wherein the second housing has an opening for bass reflex tuning. The first and second housings are arranged at least partially next to one another. The loudspeaker system has at least two loudspeakers, wherein each of the at least two loudspeakers has at least one voice coil movable along an axis. The at least two loudspeakers are arranged on at least two opposite side surfaces of the first housing, wherein at least one of the at least two loudspeakers, preferably a so-called interior loudspeaker, is in acoustic interaction with the interior of the second housing. Furthermore, it can be advantageous if the axes of these loudspeakers are not coaxial.In the context of this invention, the axis of a loudspeaker is defined as the axis oriented in the direction of the reciprocating motion of the voice coil. Furthermore, in the context of this invention, the internal loudspeaker is defined as the loudspeaker that is arranged on a side surface of the first housing and radiates into the interior of the second housing. Furthermore, in the context of this invention, the external loudspeaker is defined as the loudspeaker that is arranged on a side surface of the first housing and radiates into the environment. BME016 4In the context of this invention, an acoustic interaction with the interior of the second housing is preferably understood to mean that the corresponding loudspeaker radiates directly into the interior of the second housing. By definition, the horizontal view is the view in which the loudspeaker system has a smaller extent in the horizontal direction than in the vertical direction. The present invention is based on the idea of ​​providing a loudspeaker system, in particular an AVAS loudspeaker system, in which one of the at least two loudspeakers forms an external loudspeaker and the other of the at least two loudspeakers forms an internal loudspeaker. The external loudspeaker preferably radiates into the environment and should preferably be able to generate sounds in the higher frequency range.The internal loudspeaker preferably projects sound into the second housing and should preferably be able to generate sounds in the lower frequency range. By adding a ventilated second housing with a bass reflex port and arranging the loudspeakers on the first housing, sound radiation in the low frequency range is enabled. The present invention is further based on the idea of ​​providing a loudspeaker system, in particular an AVAS loudspeaker system, in which the sensitive loudspeaker components, such as a magnet or a voice coil, are arranged within the - preferably closed - first housing. BME016 5The proposed loudspeaker system preferably has a frequency response in which, preferably with a sound pressure drop of -3 dB, a bass tone is located at approximately 80 Hz and the -10 dB point is located at approximately 60 Hz. According to a particularly preferred embodiment of the invention, the second housing has a second opening - also known as a sound inlet opening - wherein the second opening is positioned directly in the axis of the at least one of the at least two loudspeakers. The second opening is preferably positioned directly in front of the first housing on the axis of the at least one of the at least two loudspeakers that is in acoustic interaction with the interior of the second housing and is also referred to as the interior loudspeaker as above, whereby the sound radiation from the at least one of the at least two loudspeakers occurs into the interior of the second housing.The size of the second opening preferably corresponds to the size of the corresponding loudspeaker. Loudspeakers can be constructed in a wide variety of shapes. Any type of loudspeaker or sound-generating system can be used for the present invention. The structure of a conventional loudspeaker is mentioned as an example. A conventional loudspeaker comprises a basket, a voice coil, a pole core, a centering spider, a membrane, a membrane surround, and / or a magnet on which a front pole plate and a rear pole plate are arranged. The magnet is preferably a permanent magnet. The two pole plates cause the magnetic field generated by the permanent magnet to be concentrated in the region of the voice coil. BME016 6Pole plates can also contribute to heat dissipation and reduce distortion. The pole plates are preferably made of a ferromagnetic material. The voice coil, pole core, magnet, and pole plates are all components of the electromagnetic system. The voice coil is wound around a voice coil former that surrounds the pole core. The magnet and the pole plates have an opening in their center into which the pole core, with the coil freely suspended along the respective axis, is inserted. The voice coil is connected to a control unit via conductors. The pole core can also be part of the rear pole plate. The front pole plate and / or the basket have connecting elements. The basket is connected to the front pole plate by the connecting elements. The basket has a circular ring structure and holds all of the speaker's essential components together.In particular, the basket houses the diaphragm, the voice coil, and the spider. If necessary, the basket can also house the magnet. The basket is made of aluminum, steel, or high-strength plastic. The basket is configured to allow minimal interference with air movement and sound waves and to avoid unwanted resonances. The basket can also be part of the first housing. The first housing thus houses the magnet, voice coil, pole plates, and core in its formed basket. This allows the basket. BME016 7and a first housing are formed as a single piece, which eliminates the need for additional assembly of the basket within the first housing. This reduces costs and manufacturing effort. The centering spider has the common task of ensuring that the voice coil only moves axially during operation and thus does not hit the edges of the magnet or pole core, which could cause distortion or damage. The centering spider also guides the diaphragm back to its original position after deflection. Especially at low frequencies, the centering spider stabilizes the driver system and ensures increased mechanical stability. The diaphragm is directly connected to the voice coil. The voice coil is preferably bonded to the diaphragm with a heat-resistant adhesive. The diaphragm can be made of paper, plastic, or metal.In the present invention, a material is preferably used for the diaphragm that is waterproof and impermeable to dust particles or the like. If, for example, moisture penetrates the interior of the second housing, it cannot pass through the diaphragm and reach sensitive components, such as the voice coil. For example, the diaphragm can be made of Gore-Tex. ® membrane or a Gore-Tex ® A similar membrane can be used. Such a membrane is waterproof and ensures static pressure equalization between the interior of the first housing and the environment. The membrane can also be made of another material that is waterproof and ensures static pressure equalization with the environment. BME016 8The diaphragm can be conical, domed, or flat. The diaphragm can also be dome-shaped, forming a dome or an inverted cone. This allows the depth of the loudspeaker and thus of the first enclosure to be reduced. The diaphragm surround is usually circular and adapts to the shape of the diaphragm. The diaphragm surround is located on the outer edge of the diaphragm, which is not connected to the voice coil. The diaphragm surround connects the diaphragm to any loudspeaker frame. The diaphragm surround must be highly flexible and elastic in order to transmit the movement of the voice coil along its axis without damping. The diaphragm surround also has a stabilizing and centering function.The first housing, as mentioned, comprises at least two loudspeakers, wherein the at least two loudspeakers can be different types of loudspeakers. For example, the at least two loudspeakers can be a woofer, midrange speaker and / or tweeter, each covering different frequency ranges. In particular, a flat membrane can be used to emit sound only in the low-frequency range. The way a loudspeaker works is based on the basic idea of ​​converting an electrical signal into mechanical energy and then into sound waves. An electrical signal is transmitted from a control unit via conductors to the voice coil of the respective loudspeaker. The voice coil is positioned in a fixed magnetic field. A current flows through the voice coil. BME016 9The Lorentz force acts on a conductor carrying current, which is arranged in a magnetic field. Depending on the polarity, the voice coil is deflected axially forwards or backwards. Since the voice coil is directly connected to the diaphragm, the diaphragm also performs a relative movement. The movement of the diaphragm along its axis causes pressure fluctuations in the ambient air. These pressure fluctuations propagate in the form of sound waves, which are perceived as tones. The opening for the bass reflex tuning, or bass reflex ports, are tubes or openings on the second housing. They are preferably used to improve overall performance, particularly in the lower frequency range.The opening for the bass reflex tuning – also called the bass reflex port here – acts as a resonator and, thanks to the dimensions of the opening for the bass reflex tuning, its resonance can be tuned in relation to the natural resonance of the loudspeaker so that the sound radiation components of the opening for the bass reflex tuning and the membrane add up in a desired frequency range, thereby achieving a lower frequency range of reproduction. It is advantageous to use loudspeakers with a low quality factor and thus a higher efficiency. Compared to solutions with passive membranes, loudspeaker systems with openings for the bass reflex tuning are generally more cost-effective. The second enclosure with the bass reflex port is not protected against water ingress. It is recommended that the bass reflex port be positioned as low as possible when arranged horizontally. This allows any water that penetrates to drain away immediately.BME016 10from the second housing. This means that the waterproof membrane of the loudspeaker, which has an acoustic effect in the interior of the second housing, is never exposed to excessive water, salt, dust and / or dirt. Preferably, the first housing and its components, such as the at least two loudspeakers, are always constructed identically. The second housing can be adapted to the specific application. By changing the volume of the interior, the geometric dimensions of the bass reflex opening and the arrangement of the first housing on the second housing, adaptation to the respective application is possible. This makes it possible to provide an extremely inexpensive and mass-produced basic module, namely the first housing with built-in loudspeakers, and to make customer-specific adaptations inexpensively by using a cost-effective second housing, preferably made of plastic.Advantageously, a control unit for operating the loudspeaker system is arranged within the first housing. A circuit board cavity into which the circuit board of the control unit can be inserted is preferably formed within the first housing. By arranging the control unit within the first housing, the cable lengths from the control unit to the loudspeaker are significantly reduced. This makes the loudspeaker system less susceptible to electromagnetic compatibility, and the electromagnetic radiation is lower, making it easier to comply with the specified normative requirements. The control unit can also be arranged outside the first housing. The control unit can be arranged directly on the first housing or on another component of the loudspeaker system or on a component that is not part of the. BME016 11Loudspeaker system. The control unit or control units can then be connected via one or more cables which, starting from the control unit, are led through an opening in one of the side surfaces of the first housing into the interior of the first housing. In a preferred embodiment of the invention, the control unit has a circuit board which is preferably encapsulated. A circuit board cavity can preferably be formed within the first housing, in which the encapsulation process is carried out after the circuit board has been inserted and a connector has been connected. The encapsulation of the circuit board provides additional protection for the components and conductor tracks located thereon. The encapsulation protects against environmental influences which could reduce the longevity of the control unit.In addition, the mechanical stability of the circuit board is increased, which is important because solder joints could be damaged, particularly by vibrations when the vehicle is moving, and thus the functionality of the loudspeaker system could be impaired. Further advantages are the increased electrical insulation strength and improved heat dissipation. Epoxy resins, silicones, or polyurethanes are used as potting materials. A connector can be connected to the control unit. In particular, a single-pin or multi-pin connector can be soldered to the circuit board of the control unit. The connector can be led out through an opening in a side surface of the first housing and enable communication with a user interface or other control units. The preferred potting of the circuit board seals the interior of the first housing. BME016 12According to a particularly preferred embodiment of the invention, the at least one voice coil, the magnet, the front pole plate, and / or the rear pole plate are arranged entirely within the first housing. This protects all sensitive components from moisture, dirt, and / or dust, so that acoustic reproduction can always be satisfactory and durable, even in harsh environments. In a particularly advantageous embodiment of the invention, a passive membrane is arranged within the first housing instead of a loudspeaker. A passive membrane, or passive radiator, is a loudspeaker membrane without its own vibration drive. The passive membrane has a conventional loudspeaker chassis. The passive membrane vibrates in response to the movement of the active loudspeaker, thus contributing to a more efficient movement of the air in the housing, resulting in amplified and deeper bass reproduction.The passive membrane can also be implemented by one or more vibratable housing walls of the second housing. For example, such a vibratable housing wall can be the body structure of the vehicle. The advantage of passive membranes over bass reflex ports is that they do not generate port noise. According to a particularly preferred embodiment of the invention, the rear pole plate of the loudspeaker, which is arranged on one side surface, is arranged closer to an opposite side surface than the rear pole plate of the loudspeaker, which is arranged on the opposite side surface. This type of arrangement of the loudspeakers enables a particularly compact design, particularly in the horizontal direction when viewed from a horizontal perspective. BME016 13ly. In the simplest case, the opposite side surfaces are arranged parallel to one another and the at least two loudspeakers are arranged mirror-inverted. Advantageously, the axis of a loudspeaker running on an imaginary line does not intersect any other loudspeaker at any point. Thus, the two loudspeakers arranged on and in the first housing are arranged at least partially vertically next to one another in the first housing. This allows components which have a smaller vertical extent to be cleverly arranged next to one another, which increases the compactness of the first housing. In addition to the improved compactness, this has the advantage that, in contrast to a coaxial arrangement, when operating with broadband signals up to the high-frequency range, a significant deviation in the amplitude-frequency response, even leading to total cancellation, is not to be expected.In the simplest case, the axes of the at least two loudspeakers are arranged parallel and spaced from one another. The distance between the two axes is preferably between half a mean diameter and a mean diameter of the at least two loudspeakers. In a preferred embodiment of the invention, the first housing is made of an electrically and / or thermally conductive material. For example, the first housing can be made of a metal or a metal alloy, preferably zinc or aluminum. The first housing, including the loudspeakers and the electronics, such as the control unit, is preferably designed to be compact. During operation, heat is generated, which is difficult to manage due to the reduced installation space. BME016 14can be dissipated more easily. By selecting the appropriate material for the first housing, heat can be dissipated from the interior of the first housing. On the side surface or surfaces of the first housing that are not directly adjacent to the second housing and on which one or more of the at least two loudspeakers are preferably arranged, convection cooling can take place due to the airstream. The level-dependent air flow caused by the bass reflex channel cools the first housing on the sides that are adjacent to the second housing. It is also advantageous if the first housing has EMC shielding. This can be achieved, for example, by making the first housing from a metal alloy. This can significantly reduce the influence and emission of electromagnetic radiation.It can also be advantageous if the first housing is a die-cast metal component. This enables simple, cost-effective, and mass-market production, and such a component can also meet requirements for EMC shielding and thermal conductivity. In less temperature-sensitive applications, the first housing is preferably made of a plastic or a similar material. This reduces manufacturing costs and simplifies production and weight. Fiberglass or carbon fiber reinforced plastic (GFRP) materials can also be used, although it should be noted that CFRP materials can also provide EMC shielding. BME016 15The first and second housings can be connected to one another via connecting means - preferably detachably. For example, the connecting means can create a clamping and / or snap-in connection. This allows the two housings to be easily connected to one another and, preferably, easily separated if necessary, e.g. for maintenance / repair or replacement. The first housing can be made of metal, for example, and the second housing of a different material, such as plastic. At the end of the product cycle, the two housings can be separated from one another and the materials, in this example metal and plastic, can be easily recycled. The one-piece design of the first housing and the basket also simplifies the recycling process. According to a further advantageous development of the invention, the second housing has a cavity into which the first housing can be fully or partially inserted.When the first housing is inserted into the cavity of the second housing, the connection between the two can be established. When this connection is established, an electrical connection can be created between the first housing and the second housing using a suitable electrical contact, e.g. a plug and mating plug, via which electrical connection the control unit in the first housing can be connected to a control system of the motor vehicle. In one example, the first and second housings are connected to one another using a snap-in or clamp-in connection. The first housing can be pressed - preferably into a cavity - in the side walls of the second housing and then. BME016 16snap, screw or clamp. The advantages of such detachable connections are easy assembly with or without simple tools, repeatable disassembly and assembly, and high reliability and durability compared to the use of an entire housing. In a particularly advantageous embodiment of the invention, a seal is arranged between the first housing and the second housing. The seal is preferably made of an elastomer. The seal is preferably arranged between the first housing and the second housing around the second opening, i.e. the sound inlet opening. Elastomers are polymers that have high elasticity and flexibility, which makes it possible to return to their original shape after deformation under stress. This means that the first housing can be detached from the second housing as often as required without the sealing properties being negatively affected.There are various types of elastomers, such as nitrile rubber, silicone, ethylene-propylene-diene monomer, or fluoroelastomers. The control unit advantageously has a single-channel or multi-channel control unit. Preferably, each channel controls one of the at least two loudspeakers separately. The control unit, which is arranged within the first housing, can be equipped with a power amplifier. The two loudspeakers can also be connected in parallel so that, when supplied with an alternating signal, both membranes are deflected in the same direction. Measurement-wise. BME016 17The two loudspeakers act like a single loudspeaker with new properties. By arranging the loudspeakers in opposing directions within the first enclosure, the required volume of the enclosure is halved due to the double spring stiffness of the sequentially acting membrane suspensions, while maintaining the same lower cutoff frequency. This is because the ratio of the total spring stiffness to the air spring stiffness of the enclosure is decisive for the same enclosure resonance. This enables the creation of compact loudspeakers with a particularly low cutoff frequency, which would not be possible with a closed enclosure. Furthermore, when the two loudspeakers are arranged in opposing directions, non-linearities in the spring characteristic of the suspension and the magnetic force factor of the voice coil partially cancel each other out, which improves the acoustic quality, particularly in the high frequency range. It is advantageous to use different loudspeaker types.The combination of identical or different loudspeakers within the first enclosure can also be supported by appropriate external circuitry, such as a crossover or filtering within a control unit. With the crossover, the signals are divided into different frequency ranges by an amplifier controlled by a control unit. The separated frequency ranges are then assigned to the corresponding loudspeakers. Various filter types, such as low-pass filters, high-pass filters, and band-pass filters, can be used for this purpose. For example, a woofer produces bass frequencies, a midrange speaker produces medium frequencies, and a tweeter produces high frequencies. BME016 18According to a further advantageous development of the invention, a grill is attached to at least one loudspeaker. The grill is preferably arranged on the loudspeaker that does not acoustically interact with the interior of the second housing. However, a grill can also be arranged on each individual loudspeaker in the loudspeaker system. The grill is intended to protect the sensitive components on the outside of the loudspeaker from environmental influences. The grill can be removable. The grill has a frame and an acoustically transparent material, or a metal or plastic grille. The grille can be mesh-shaped. A mesh-shaped grille has a first group of bars, wherein the bars of this first group of bars run parallel to one another.In addition, a mesh-like grille has a second group of bars, with the bars of this group also running parallel to one another. The bars of the first group of bars are preferably arranged at an angle, particularly preferably orthogonally, to the bars of the second group of bars. The grille can also have just one group of bars. The shape of the frame preferably adapts to the shape of the loudspeaker, in particular to the shape of the membrane surround. In a particularly advantageous embodiment of the invention, the first housing and the basket are one-piece. As already described above, the basket can carry the magnet, the membrane, the voice coil, and / or the front and / or rear pole plate and / or the centering spider of the loudspeaker. BME016 19According to a further advantageous development of the invention, the second housing is preferably made of plastic. Plastic components are generally durable and inexpensive to manufacture. In addition, their shape can often be adapted as desired, so that the second housing can be used as an adjusting screw for the specific application. Advantageously, the second housing and thus the interior of the second housing is formed by a body structure of the motor vehicle. The first housing can be connected to the body structure in such a way that the interior – or cavity – of the second housing is formed. In this case, no separate second housing needs to be provided, which reduces the installation space. This may make it possible to increase the diaphragm diameter and, with it, significantly increase the low-frequency sound level.The inner loudspeaker is preferably arranged in such a way that its outer membrane side acts on the air volume in the interior of the second housing or comes into direct contact with it. According to a preferred embodiment of the invention, the inner loudspeaker emits sound directly into the interior of the second housing through the second opening, and the outer loudspeaker emits sound into the environment. The environment is a room or volume that is not delimited by one of the side walls of the first or second housing. The loudspeaker system can also comprise more than two loudspeakers. For example, three, four, five or more loudspeakers can be provided. In particular, more than. BME016 20Two loudspeakers are arranged within the first housing or on the first housing. Not all loudspeakers have to be arranged on or on two opposite side walls. Loudspeakers can also be arranged on the second housing. The loudspeakers arranged on the second housing can radiate into the environment or into the interior of the second housing. According to an advantageous development of the invention, at least one maintenance hatch is formed on at least one side surface of the first housing. The maintenance hatch can be opened to carry out maintenance work or assembly work, such as installing the plug, within the first housing. The maintenance hatch is closable and is formed with a form-fitting connection with one or more side surfaces of the first housing. The maintenance hatch can be opened or closed using a hinge mechanism.The advantage of such a maintenance hatch is that the speaker system does not need to be disassembled to make changes within the first housing. An opening can be formed in the maintenance hatch, into which a waterproof membrane, preferably a Gore-Tex membrane, can be inserted. ® Membrane is inserted. Through the membrane, a static pressure equalization of the interior of the first housing with the environment takes place. The opening can also be arranged at any other location of the first housing with the pressure equalization membrane. A further aspect of the present invention relates to a method for forming, in particular, a previously described loudspeaker system for a motor vehicle with a body structure, in particular for an electric vehicle, wherein BME016 21the loudspeaker system comprises a first housing, a second housing and at least two loudspeakers. The second housing has an opening for bass reflex tuning. Each loudspeaker has a voice coil movable along an axis. The two loudspeakers are arranged on a first and a second side surface of the first housing, wherein the first and second side surface are arranged opposite one another. The axes of the at least two loudspeakers are not coaxial. The first housing is arranged on the second housing, preferably detachably, such that at least one of the at least two loudspeakers is in acoustic interaction with the interior of the second housing. Furthermore, it has proven advantageous if the second housing is formed by a body structure of the motor vehicle, which for example comprises a cavity with the second opening.A further aspect of the present invention relates to a motor vehicle, in particular an electric vehicle, with a loudspeaker system as described above. Two exemplary embodiments of the present invention are described in detail below with reference to the accompanying drawing. Figure 1 shows a schematic representation of the loudspeaker system, with a first and second housing, two loudspeakers, a grill, and a control unit. Figure 2 shows a schematic representation of the loudspeaker system, with a first and second housing and two loudspeakers. BME016 22Figure 3 shows a schematic representation of the loudspeaker, Figure 4 shows a schematic representation of a motor vehicle with the loudspeaker system according to a second exemplary embodiment, and Figure 5 shows a schematic representation of a motor vehicle with the loudspeaker system according to a third exemplary embodiment. Identical or functionally identical parts or features are identified by the same reference numerals in the following detailed description of the figures. Likewise, not all identical or functionally identical parts or features are provided with a reference numeral in the figures. Figures 1 to 3 show a first exemplary embodiment of the invention. Figure 1 shows a schematic representation of the loudspeaker system 1, in particular the AVAS loudspeaker system. The loudspeaker system 1 comprises a first housing 10, a second housing 20, two loudspeakers 30, and a control unit 50.The first housing 10 comprises a first side surface 11, a second side surface 12, an interior 14, and can have a cuboid structure. The interior 14 of the first housing 10 is completely sealed against environmental influences. This enables use in harsh conditions, such as those encountered in daily driving. BME016 23motor vehicle. The first housing 10 can take on any shape; in particular, the first housing 10 can adapt to the available installation space, which is usually predetermined by the body or remaining deformation areas. The first housing 10 can be made of an electrically and / or thermally conductive material or a metal or a metal alloy. In particular, the first housing 10 can be made of zinc or aluminum. This significantly improves the EMC properties of the loudspeaker system 1. The first housing 10 further comprises the control unit 50. A printed circuit board cavity 18 can be formed within the first housing 10. The control unit 50 can be inserted into the printed circuit board cavity 18. The control unit 50 comprises a printed circuit board 51 and an amplifier.The control unit 50 can be connected to a user interface or another control device within the motor vehicle using a connector 52. The connector 52 can be designed as a multi-pin connector 52 and can be soldered to the circuit board 51. The connector 52 can also be connected to the circuit board 51 via a connector strip which is attached to the circuit board 51. The circuit board 51 arranged in the circuit board cavity 18 of the first housing 10 can be potted. The potting can take place before the circuit board 51 is inserted into the circuit board cavity 18 or while the circuit board 51 is inserted or connected within the circuit board cavity 18. In the latter case, the contact point between the connector 52 and. BME016 24Printed circuit board 51 is also encapsulated. In addition, an opening 53, through which the connector 52 is guided into the interior 14 of the first housing 10 or the encapsulation, is sealed. The printed circuit board cavity 18 can also be arranged on any other side surface 11 of the first housing 10. The printed circuit board cavity 18 is arranged below the internal loudspeaker 90. Communication between the control unit 50 and the loudspeaker 30 takes place via cable wires. The control unit 50 can be designed as a multi-channel control unit 50, whereby each loudspeaker 30 can be controlled via its own channel. The length of the cable wires that carry the communication between the control unit 50 and the loudspeaker is short. The EMC behavior of the loudspeaker system 1 is therefore particularly good, both in terms of EMC sensitivity and EMC interference emission. The first housing 10 comprises at least two loudspeakers 30.The respective loudspeaker 30 comprises a basket 40, a centering spider 32, a voice coil 34, a pole core 39, a membrane 35, a membrane surround 38 and a magnet 33, on which a rear pole plate 36 and a front pole plate 37 are arranged. The loudspeaker 30 has an axis L, wherein the voice coil 34 is movable in the axis L. The respective loudspeaker 30 has an interior region 31 in which the sensitive components, in particular the. BME016 25Voice coil 34, are arranged. The membrane 35 is waterproof and impermeable to dirt, so that the membrane 35 represents the boundary between the interior area 31 and the exterior area, for example the interior area 21 of the second housing 20. In the area of ​​the side surfaces 11 of the first housing 10, the membrane bead 38 is arranged on the membrane 35. The membrane bead 38 is connected to the end of the membrane that is not connected to the voice coil 34. The membrane bead 38 is usually circular in shape. The membrane bead 38 is made of a material with high elasticity and flexibility, so that it does not distort the vibration behavior of the membrane 35. The membrane 35 is arranged within a basket 40 and has a conical structure. The basket 40 can be made of aluminum or plastic. The centering spider 32 is arranged within the basket and keeps the membrane 35 and the voice coil 34 centered.The front pole plate 37 is arranged on an underside of the basket 40. The front pole plate 37 is connected to the basket 40 via connecting elements. The basket 40 has a lower circular ring 41 and an upper circular ring 42, wherein the two circular rings 41, 42 are connected to one another via connecting webs 43. The upper circular ring 42 has a larger outer diameter than the lower circular ring 41. A magnet 33 is arranged between the front pole plate 37 and the rear pole plate 36. The magnet 33 and the front pole plate 37 are circular. The rear pole plate 36 has the shape of a circular ring or a ring. BME016 26The magnet 33 is preferably designed as a permanent magnet. The two pole plates 36, 37 carry the electrical flux of the permanent magnet. The pole plates 36, 37 are made of a ferromagnetic material so that the electrical flux is amplified and concentrated. The rear pole plate 36 can also form the pole core 39. The pole core 39 and the rear pole plate 36 are thus formed as a single piece, which is particularly advantageous during assembly and with regard to losses. The pole core 39 can also be connected to the rear pole plate 36. The voice coil 34 is wound around the voice coil body 44, with the voice coil being arranged around the pole core 39. The voice coil 34 is arranged radially between the pole core 39 and the magnet 33. An air gap 45 is arranged between the magnet 33 and the voice coil 34. The voice coil 34 is freely mounted so that it can move, particularly in the axial direction.The membrane 35 is mechanically connected to the voice coil 34. If the voice coil 34 moves in the axial direction, the membrane 35 does the same. The membrane moves the air molecules so that sound spreads in the form of waves. The respective loudspeaker 30 can also comprise a grill 70. The grill 70 can be arranged in the manner of a protective grid and / or protective net in front of the membrane 35 in a radiation direction. The grill 70 is configured to protect the loudspeaker 30 and in particular the membrane 35 from external influences. The two loudspeakers 30 are arranged on two opposite side surfaces 11, 12 of the first housing 10, wherein the. BME016 27The axes L of the two loudspeakers 30 do not run coaxially and preferably do not intersect at any point. According to the exemplary embodiment shown in Figure 1, the two opposite side surfaces 11, 12 are arranged parallel and spaced from one another. One of the two loudspeakers 30 is arranged on each of the two opposite side surfaces 11, 12, the arrangement of the two loudspeakers 30 being mirror-inverted. One of the two loudspeakers 30 is the so-called external loudspeaker 91, which will be explained later, and the other of the loudspeakers 30 is the internal loudspeaker 90, which will also be described later. It can also be seen from Figure 1 that the two axes L of the two loudspeakers 30 are arranged parallel and spaced from one another, with a distance A between the two axes L being selected to be as small as possible in order to preferably avoid possible disruptive cancellations in the frequency response.For example, the distance A between the axes L of the loudspeakers 30 is between half a mean diameter D. M and about two average diameters D M of at least two loudspeakers 30. Preferably, the distance A is approximately 0.5D M ≤ A ≤ 2D M , even more preferably 1D M ≤ A ≤ 1.5D M . In addition, the mean diameters D M The speakers vary in size. The average diameter D M of the internal loudspeaker 90 can be between 1.1 and 1.5 times larger than the average diameter D M of the external loudspeaker 91 or vice versa. Preferably, the average diameters D M the inner loudspeaker 90 and the outer loudspeaker 91 are of equal size. BME016 28 The inner speaker 90 has a first depth T1. The outer speaker 91 has a second depth T 2 auf.The depth T1, T2 is the spatial extent of a loudspeaker 30 along its axis (L). The first and second depths T1 and T2 can be different or the same. The first distance D1 is the distance from the rear pole plate 36 of the inner loudspeaker 80 to the second side surface 12 of the first housing 10. The second distance D2 is the distance from the rear pole plate 36 of the outer loudspeaker 91 to the first side surface 11 of the first housing. For example, the first distance D1 can be between one-eighth and approximately two times the first depth T1 and / or the second distance D2 can be between one-eighth and approximately two times the second depth T2. Preferably, the first distance D1 is approximately 0.125T2≤D1≤2T 2. Further preferably, the second distance D2 is approximately 0.125T1≤ D2 2T1. Particularly preferred is T1≤ D2and / or T2 D1.even more preferably 0.125T2≤ D1 ≤ 1T2and / or 0.125T1≤ D2 1T 1.In addition, the first distance D1 is preferably between one eighth and approximately 4 times the first depth T1. Preferably, the first distance D1 is approximately 0.125D1≤T1≤4D1, even more preferably 0.125D1≤T1≤1D1. Further preferably, the second distance D2 is between one eighth and approximately 4 times the second depth T2. Preferably, the first distance D1 is approximately 0.125D2. 4D2, more preferably 0.125D1≤ T1≤ 1D1. BME016 29The loudspeakers 30 are arranged such that they are offset from one another from a vertical perspective. As a result, the two loudspeakers 30 are arranged at least partially next to one another within the first housing 10. The rear pole plate 36 of the inner loudspeaker 90 can be arranged closer to the opposite second side surface 12 than the rear pole plate 36 of the outer loudspeaker 91 is to the opposite first side surface 11. The circuit board cavity 18 can be arranged on the side surface 11 on which the outer loudspeaker 91 is also arranged. More than one loudspeaker 30 can also be arranged on a side surface 11, 12 of the first housing 10. In particular, two, three, four or more loudspeakers 30 can be arranged on a side surface 11, 12 of the first housing 10. Different loudspeakers 30 can be arranged within the first and / or second housing 10, 20.Loudspeakers 30 for generating high frequencies, low frequencies, and mid-frequency can be arranged on the loudspeaker system 1. The second housing 20 has side surfaces 23, an interior 21, an opening 22 for the bass reflex tuning, and a second opening 25. The opening 22 for the bass reflex tuning and a second opening 25 are connected to one another by the interior 21 of the second housing 20. The opening 22 for the bass reflex tuning can, viewed from a horizontal view, be arranged in the intended manner. BME016 30For use, the second housing 20 may be arranged near the bottom. The opening 22 for bass reflex tuning may also be referred to as a bass reflex opening 22 and may also be designed as a bass reflex channel. The first housing 10 and the second housing 20 may be arranged at least partially adjacent to one another. In this case, the first housing 10 is positioned relative to the second housing 20 such that one of the loudspeakers 30 is arranged in front of or in the second opening 25, whereby this loudspeaker 30 is in acoustic interaction with the interior 21 of the second housing 20. This loudspeaker 30 is the inner loudspeaker 90 and is arranged on the first side surface 11 of the first housing 10 and radiates into the interior 21 of the second housing 20. On the second side surface 12 facing away from the second housing 20, the other of the two loudspeakers 30, the so-called outer loudspeaker 91, is arranged, which radiates into the environment.The external loudspeaker 91 preferably serves to generate medium- to high-frequency sounds, while the internal loudspeaker 90 preferably serves to generate low-frequency sounds, preferably sounds with a frequency range of up to 80 Hz, more preferably up to 60 Hz, with a level drop of -10 dB. The first housing 10 and the second housing 20 can be connected to one another via detachable connecting means, for example, a snap-in connection. The first housing 10 can have a locking lug, and the second housing 20 can have a locking groove. BME016 31When the two housings 10, 20 are connected, the locking lug of the first housing 10 engages in the locking groove of the second housing 20 and prevents the components from accidentally coming loose from one another. The first housing 10 can also be screwed and / or clamped to the second housing 20 in order to create a permanent mechanical connection between the two components. The first housing 10 and the second housing 20 can also be glued to one another. The first housing 10 can also be inserted or placed into the second housing 20. Furthermore, the first housing 10 and the second housing 20 can not touch one another. A seal 80 can be arranged between the first housing 10 and the second housing. The seal 80 is preferably arranged around the second opening 25 and seals the interior 21 of the second housing 20 against environmental influences, such as dust, stone chips and moisture.The seal 80 is preferably designed as an elastomer seal. Elastomer seals have the advantage of being highly elastic and flexible, which allows gaps to be filled in a form-fitting manner and allows repeated installation and removal of the first housing without difficulty. Furthermore, as shown in Figure 1, the second housing 20 can have a cavity 26 into which the first housing 10 can be at least partially inserted and which can correspond to the shape of the first housing 10. The second opening 25 is arranged in the cavity 26. BME016 32The first housing 10 is made of a metal, a metal alloy, or a thermally and electrically conductive material. The first housing 10 can also be made of plastic. Additional loudspeakers 30 can also be arranged on the second housing 20. The loudspeakers 30 can be arranged on each side surface 23 of the second housing 20. The loudspeakers 30 can each radiate into the interior 21 of the second housing 20 or into the surroundings. More than one loudspeaker can also be arranged on each side surface 23 of the second housing. The second housing 20 is made of plastic. The second housing can also be made of metal, a metal alloy, or the like.For simplified maintenance, the maintenance hatch can be arranged on the underside 4 of the motor vehicle 2, whereby the first housing, together with the two loudspeakers 30 and the control unit 50, can be removed for maintenance purposes, for replacement, or for repair. Figure 4 shows a motor vehicle 2, wherein the loudspeaker system 1 according to a second exemplary embodiment is arranged on the underside 4 of the motor vehicle 3. In contrast to the exemplary embodiment described so far, the second housing 20 is not formed by a separate component, but is formed by the body structure 3 of the motor vehicle 2, which has a recess 5 forming the interior 21. BME016 33The second housing 20 has, as previously described, a first opening 22 and a second opening 25, wherein the first housing 10 can be releasably fastened to the second housing 20, i.e., in this embodiment, to the body structure, to form the loudspeaker system 1, such that one of the two loudspeakers 30, i.e., the interior loudspeaker 90, is positioned in front of or in the second opening 25 and can radiate into the interior 21 of the second housing 20. Fig. 5 shows a schematic representation of a motor vehicle with the loudspeaker system according to the first embodiment.

[0002] BME016 34 List of reference symbols 1 Loudspeaker system 2 Motor vehicle 3 Body structure 4 Underside 10 First housing 11 First side surface 12 Second side surface 14 Interior 18 Circuit board cavity 14 Interior 20 Second housing 21 Interior 22 Opening 23 Side surface 25 Second opening 26 Cavity 30 Loudspeaker 31 Interior 32 Centering spider 33 Magnet34 Voice coil 35 Diaphragm 36 Rear pole plate 37 Front pole plate 38 Diaphragm surround BME016 35 39 pole cores 40 Korb 41 Lower circular ring 42 Upper circular ring 43 Connecting bars 44 Voice coil body 45 Air gap 50 Control unit 51 Circuit board 52 Connector 53 Opening 70 Grill 80 Seal90 Interior speaker91 Exterior speaker L Achse A Abstand D1First distance D2Second distance D M Mean diameter T1First depth T2Second depth

Claims

BME016 36Patent claims 1. Loudspeaker system (1) for a motor vehicle, in particular for an electric vehicle, comprising: ^a first housing (10), ^a second housing (20), the second housing (20) having an opening (22) for bass reflex tuning, ^wherein the first and second housings (10, 20) are at least partially arranged next to one another, ^at least two loudspeakers (30), each loudspeaker (30) having a voice coil (34) movable along an axis (L), ^wherein the at least two loudspeakers (30) are arranged on two opposite side surfaces (1112) of the first housing (10), ^wherein at least one of the at least two loudspeakers (30) is in acoustic interaction with the interior (21) of the second housing (20), ^wherein the axes (L) of the at least two loudspeakers (30) are not coaxial.Loudspeaker system (1) according to one of the preceding claims, characterized in that the second housing (20) has a second opening (25), wherein the second opening (25) is positioned directly in the axis (L) of at least one of the at least two loudspeakers (30).

3. Loudspeaker system (1) according to one of the preceding claims, characterized in that a control unit (50) for operating the loudspeaker system (1) is arranged in the first housing (10). BME016 374. Loudspeaker system (1) according to one of the preceding claims, characterized in that the control unit (50) has a circuit board (51), which is preferably encapsulated.

5. Loudspeaker system (1) according to one of the preceding claims, characterized in that a voice coil (34), a magnet (33), and / or a front and / or rear pole plate (36, 37) of at least one of the at least two loudspeakers (30) are arranged entirely within the first housing (10).

6. Loudspeaker system (1) according to one of the preceding claims, characterized in that the second housing (20) is made of plastic.

7. Loudspeaker system (1) according to one of the preceding claims, characterized in that at least one of the at least two loudspeakers (30) is arranged at least partially on or within the interior (21) of the second housing (20). 8.Loudspeaker system (1) according to one of the preceding claims, characterized in that the rear pole plate (36) of the loudspeaker (30) arranged on one side surface (11) is arranged closer to an opposite side surface (11) than the rear pole plate (36) of the loudspeaker (30) arranged on the opposite side surface (11). BME016 389. Loudspeaker system (1) according to one of the preceding claims, characterized in that the axis (L) of a loudspeaker (30), running on an imaginary line, does not intersect any other loudspeaker (30) at any point.

10. Loudspeaker system (1) according to one of the preceding claims, characterized in that the first housing (10) is made of an electrically and / or thermally conductive material and / or a metal or a metal alloy, preferably zinc or aluminum.

11. Loudspeaker system (1) according to one of the preceding claims, characterized in that the first housing (10) and the second housing (20) are connected to one another via a preferably detachable connection, preferably a snap-in or clamping connection. 12.Loudspeaker system (1) according to one of the preceding claims, characterized in that a seal (80), preferably an elastomer seal, is arranged between the first housing (10) and the second housing (20).

13. Loudspeaker system (1) according to one of the preceding claims, characterized in that the control unit (50) is a single-channel or multi-channel control unit (50), wherein in the multi-channel control unit (50) each channel controls one of the at least two loudspeakers (30) separately.

14. Loudspeaker system (1) according to one of the preceding claims. BME016 39characterized in that a grill (70) is attached to at least one of the at least two loudspeakers (30); preferably, the grill (70) is arranged on the loudspeaker (30) that does not acoustically interact with the interior (21) of the second housing (20).

15. Loudspeaker system (1) according to one of the preceding claims, characterized in that the first housing (10) forms a basket (40) which carries a magnet (33), a membrane (35), a voice coil (34), the front pole plate (36) and / or the rear pole plate (37) as well as the centering spider (32) of the loudspeaker (30).

16. Loudspeaker system (1) according to one of the preceding claims, characterized in that the second housing (20) and its interior (21) are formed by a body structure of the motor vehicle.17.Loudspeaker system (1) according to one of the preceding claims, characterized in that one of the at least two loudspeakers (30) is an internal loudspeaker (90) that radiates directly into the interior (21) of the second housing (20), and that the other of the at least two loudspeakers (30) is an external loudspeaker (91) that radiates into an environment.

18. Loudspeaker system (1) according to one of the preceding claims, characterized in that a maintenance hatch is formed on at least one side surface (11) of the first housing (10). BME016 4019. A method for forming a loudspeaker system (1) for a motor vehicle (2) with a body structure (3), in particular for an electric vehicle, in particular with the features of one of the preceding claims, wherein the loudspeaker system (1) comprises a first housing (10), a second housing (20), and at least two loudspeakers (30), wherein the second housing (20) has an opening (22) for bass reflex tuning, wherein the respective loudspeaker (30) has at least one voice coil (34) movable along an axis (L), wherein the at least two loudspeakers (30) are arranged on a first and a second side surface (11, 12) of the first housing (10), which are arranged opposite one another, wherein the axes (L) of the at least two loudspeakers (30) are not coaxial, and wherein the first housing (10) is arranged on the second housing (20) in such a way thatthat at least one of the at least two loudspeakers (30) is in acoustic interaction with the interior (21) of the second housing (20).

20. Method according to claim 19, characterized in that the second housing (20) is formed by a recess (5) in the body structure (3).

21. Motor vehicle (2), in particular an electric vehicle, with a loudspeaker system (1) according to one of the preceding claims.

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