LU500838B1 - sound transducer device - Google Patents

Abstract

The invention relates to a sound transducer device (1) comprising a substrate (17) and a sound transducer (2) which is acoustically connected to one end of a sound channel (12) of the substrate (17). The sound transducer device is characterized in that the switching device (1) has a waterproof acoustic membrane (5) covering another end of the sound channel (12).

Description

1LU500838

sound transducer device

The invention relates to a sound transducer device. Furthermore, the invention relates to a method for producing such a sound transducer device, a sound transducer device produced by means of the method, a communication device comprising the

Sound transducer device and the use of the same.

Acoustic transducer devices, particularly in communications applications, must have many

work perfectly and reliably for years and must withstand a wide variety of environmental influences, especially within the context of their respective application. In addition to a defined temperature range in the application, resistance to corrosive effects such as water, acids or oils and protection against

Penetration of dust or other foreign bodies relevant environmental influences, which

Transducer devices may be exposed. There are a number of standards to indicate resistance to such environmental influences. especially the

Protection classes IP69 or IP69K according to DIN EN 60529 (VDE 0470) (Version 2019) are used for

Identification of electronic devices that meet the highest standards against dirt and moisture. The protection class designation consists of the letters “IP” (“International Protection” or “Ingress Protection”) and two numbers. The first digit stands for protection against dust and foreign bodies. The higher this number, the better the device is protected against the finest dust. "6" stands for absolute dust tightness. The second number indicates the protection against water in different intensities or scenarios.

While the 1 means protection against light dripping water, the 9 implies as the highest

Index the protection against the ingress of water at high pressure or

steam jet cleaning.

Although both types of protection relate to the protection provided by enclosures, they differ in the scope of the devices concerned. The IP69k carries the special

Requirements for electrical or electronic devices in mobile outdoor applications such as road vehicles or agricultural machines. It is regulated in the ISO 20653:2013 standard. IP69 stands for the dust and water resistance of general electrical equipment, which also includes, for example, computers for use in various applications, for example with an integrated capacitive touchscreen, or medical technology. The criteria are defined in the DIN EN60529 standard. The

Protection classes IP69 and IP69k do not stand for different qualities, but differ in their area of application ("Electrical equipment in general" and "Electrical equipment in road vehicles").

Acoustic transducer devices are used in many of these applications. In particular

Applications with environmental influences, especially with water, dust or viscous

2LU500838

Liquids such as wax or tree resin come into contact with the

Sound transducer device are protected from environmental influences. It is known, for example, to use grilles to cover acoustic transducer devices. However, these have the disadvantage that they are not water-repellent and therefore the

Do not meet protection classes IP69 or IP69K.

There is therefore a need to provide a sound transducer device that meets the requirements of protection classes IP69 and IP69K and at the same time sound reception, processing or

shipment are not negatively affected. In addition, penetration of liquids, even under pressure, must be avoided, for example by penetrating into slits, openings, or deep indentations. Furthermore, it is necessary that the surface of the

Sound transducer device can be painted.

The present invention is therefore based on the object of providing a sound transducer device which meets the requirements of IP69 and IP69K and thus a reliable one

Protection against the ingress of dust and liquids such as water, tree sap or

Grows in the liquid state of aggregation, and on the other hand meets the requirements for reliable sound signal processing, for example with regard to sufficient sensitivity in a predetermined frequency range.

This problem is solved by means of a sound transducer device specified in claim 1 .

The acoustic transducer device according to the invention comprises a substrate and an acoustic transducer which is acoustically connected to one end of an acoustic channel of the substrate and is characterized in that the switching device has a waterproof acoustic membrane which covers another end of the acoustic channel.

A membrane according to the invention has an expansion in a Cartesian

Coordinate system with x,y and z-axis in the z direction — corresponds to the membrane thickness in

Installation position - has a smaller extent than in the x,y plane. An acoustic membrane is understood to mean a membrane which, after being attached to the substrate, can be set at least partially in vibration by sound pressure waves from the environment. The

Membrane vibration again causes sound pressure waves in the sound canal, from which

Sound transducers are received. This is possible with membranes that are designed to be flexible, as will be explained in more detail below. As a result, the membrane prevents the sound pressure waves from the environment from being received directly by the sound transducer.

A membrane is considered waterproof for the purposes of the invention if it passes the test

Protection class IP69 and/or IP69K exists. On the one hand, this allows reliable protection against the ingress of dust and liquids such as environmental influences that are to be expected

Water, tree sap or waxes in the liquid aggregate state on the other hand

3LU500838

To meet requirements for reliable sound signal processing, for example, in terms of sufficient sensitivity in a predetermined frequency range.

In addition to this, the sound converter device according to the invention particularly advantageously allows the structurally simple adaptation of the sound converter device to a given one

Installation space, since the membrane according to the invention transmits sound energy without itself requiring a large amount of additional installation space.

An acoustic transducer device is a device that produces acoustic signals in the form of

Pressure waves are converted into electrical signals, in particular an electrical voltage, or vice versa, in which an electrical voltage is converted into acoustic signals in the form

Pressure waves are converted. The pressure waves are not limited to the frequency range that is audible to humans and therefore also include pressure waves outside the audible range. The sound transducer device can be designed as a microelectromechanical system (MEMS).

An acoustic connection is understood to be a connection between two areas in which acoustic energy, in particular sound energy, can be transmitted from one area to another area. The transmission can take place through the same and/or different media. In addition, energy transfer can involve the conversion of mechanical

Energy, such as vibrational energy of the membrane, into acoustic energy or vice versa.

In a further embodiment of the sound transducer device, the substrate can

Have control device or be the control device or be incorporated into the substrate. The membrane can preferably be firmly connected to the substrate, in particular the control device. The control device can preferably include or be a printed circuit board (PCB). In the installation direction, the sound transducer can be arranged below the control device, in particular below the PCB. In particular, the sound transducer and the membrane can be arranged on opposite sides of the substrate. This has the

Advantage that the sound transducer according to the invention can be easily provided in terms of production technology, since the sound opening is arranged on the outside or the surrounding side in the installation direction of the sound transducer device. This is structurally simple

Sound transducer device, including its substrate, in particular the control device before

Protected against dust or environmental influences, such as water in particular, without having to use the

Sound transducers which require protection class IP69 and/or IP69K to require further measures on an application device.

As the outside of the sound transducer device, the side is understood that during operation

Sound transducer device facing the environment. The installation direction is the direction

4 LU500838 understood, along which the transducer device is moved to turn it into a

Install application device.

According to a further embodiment, the membrane can be arranged on the substrate, in particular glued on, in particular this can be done by means of at least one adhesive layer. This has the additional advantage that by arranging it directly on the substrate, preferably the control device, in particular a PCB, both the sound transducer and the substrate are structurally particularly simple and reliable against the ingress of

are protected from environmental influences. With this type of attachment, the membrane in the area of the

Sound channel have a sound-transmitting area. A sound-transmitting area is understood to be an area of the membrane that oscillates when subjected to sound pressure waves and thus transmits sound energy into the sound channel.

The other end of the sound channel may include a sound port. A sound opening is understood to be an opening through which sound pressure waves reach the sound channel. As will be described in more detail below, these sound pressure waves are generated through the membrane, particularly the sound-transmitting region of the membrane. The

Acoustic transducer device can be configured such that a sound pressure wave the

Sound channel passes before it is received by the sound transducer.

The sound converter can have a sound converter housing and a sound receiver and/or transmitter. The sound converter housing can at least partially enclose an interior space of the sound space. In addition, in the assembled state, the substrate

Partially close off the interior of the transducer. The sound receiver and/or transmitter can be arranged in the interior of the sound transducer. In addition, the

Interior of the transducer to be acoustically connected to the sound opening.

The membrane can complete an acoustic space, which consists of the sound channel and the

Interior of the transducer composed. The acoustic space can be completely closed off by the aforementioned components. Such training has the

Advantage that a predetermined resonant frequency range can be set in a structurally simple manner by providing a predetermined volume for the acoustic space. This offers the advantage that unwanted frequency ranges are filtered out by the sound transducer device. A further advantage is that the sound signal transmitted, in particular by the membrane, in particular the sound-transmitting area of the area, is amplified,

Suitable membranes can have, for example, a polyimide, in particular a duroplastic polyimide, in particular poly(4,4′-oxydiphenylenepyromellitimide), also called Kapton, or be formed from it. This has the advantage that such membranes, and here

> LU500838 Kapton in particular, have very good resistance to chemicals, are waterproof in the sense of IP69 or IP69K and are also electrically insulating. such

Membranes also have a high tensile strength (3 GPa), whereby such a membrane retains its flexibility. Maintaining flexibility serves to prevent or at least minimize damping of the mechanical sound transmission energy. The

Tensile strength serves to prevent or at least minimize loss of resonant capability. Such membranes and in particular Kapton also have a good

Temperature resistance, particularly in a range from -269 °C to 400 °C, giving them constant mechanical properties over the required temperature range of -40 °C to 100 °C

have properties. Such membranes can also be picked and placed

Machines are handled, which allows an arrangement with high precision, which is a further advantage in terms of manufacturing technology. Kapton in particular is also ROHS and IATF certified. Kapton can be supplied in a number of membrane thicknesses, coatings and colors so that additional desired properties can be easily implemented in manufacturing technology.

Additionally or alternatively, the membrane can have a polyester, in particular a biaxially oriented polyester, in particular a biaxially oriented polyethylene terephthalate (BOPE), for example Mylar, or be formed from it. Such polyesters, in particular

BOPE, especially Mylar, are chemical resistant and waterproof according to the

Protection classes IP69 or IP69K. Such membranes also have a high tensile strength (4 GPa), with such a membrane retaining its flexibility. The receipt of

Flexibility serves to prevent or at least minimize attenuation of the mechanical sound transmission energy. Tensile strength is used to compensate for loss of

to prevent or at least to minimize the ability to resonate. Such membranes and in particular Kapton also have good temperature resistance, in particular in a range from -70 °C to 150 °C, as a result of which they have constant mechanical properties over the required temperature range of -40 °C to 100 °C. Such membranes can usually also be handled using pick and place machines, what a

Arrangement with high precision allowed, which is a further advantage in terms of production technology.

Mylar in particular is also ROHS and IATF certified. Mylar is also available in a variety of membrane thicknesses, coatings, and colors to accommodate additional requirements

Properties can be easily implemented in terms of production technology.

Additionally or alternatively, the membrane can be impermeable to air and/or coatable, in particular paintable, and/or pressure-resistant, in particular up to a pressure of 10,000 kPa and/or temperature-resistant in a temperature range from -269 °C to 400 °C, in particular in a Temperature range from -70 °C to 150 °C, especially in one

Temperature range from -40°C to 100°C. An airtight membrane is particularly advantageous because it is particularly easy to coat, especially to paint, since a

6LU500838

Penetration of aerosols during coating or painting can be reliably avoided in a structurally simple manner. Preferably, the membrane consists of the same

Material.

In one embodiment, the sound transducer device can have at least one cover layer and/or at least one spacer layer and/or at least one adhesive layer.

A top layer is a layer that faces the environment directly. The surface layer is exposed to the sound pressure waves from the surrounding area. A spacer layer is understood to mean a layer which is arranged between the cover layer and the substrate.

The cover layer can be on at least one spacer layer and/or at least one

Adhesive layer can be arranged. The provision of one or more spacer layers offers the advantage that the dimension of the sound transducer device can be adjusted in the thickness direction of the substrate in order to adapt the sound transducer device, for example, to the spatial

Adapt conditions in the application device in a simple way. This is particularly advantageous because the substrates are often available in standardized sizes and therefore an adjustment in the direction of thickness is not possible or is very expensive. The cover layer can have an adhesive layer. The adhesive layer can be ring-shaped and can enclose the sound opening.

The spacer layer can have a cavity in the area of the sound opening. The

The cavity can have a round or elliptical shape in cross section, in particular transversely to the thickness direction of the substrate. A cavity cross section can be equal to one

Sound opening cross-section be executed. Alternatively, the cavity cross section can be larger than the sound opening. The cavity can be fluidly connected to the sound channel.

In particular, the cavity can be arranged coaxially to the sound channel.

If several spacer layers are provided, the cavity cross sections of the individual spacer layers can differ from one another. This is particularly necessary when the top layer has a convex shape, as described in more detail below. The at least one spacer layer and the cover layer can consist of the same material. The provision of one or more cavity spacer layers also offers the advantage that the acoustic space can easily be adjusted in order to obtain the desired resonant frequency range.

In an alternative embodiment, the spacer layer in the area of the sound opening cannot

have cavity. By providing one or more spacer layers without

Cavity, a resonance damping behavior of the acoustic space can be easily adjusted.

/ LU500838

The at least one spacer layer may include an adhesive layer. The

Adhesive layer can be designed as an annular adhesive layer.

The ring-shaped arrangement of the adhesive layer in the cover layer and/or the spacer layer around the sound opening has the additional advantage that the adhesive layer is easy to produce in terms of manufacturing technology.

In one embodiment, the membrane can have a thickness of 0.01 to 0.1 mm (millimeter), in particular a thickness of 0.02 to 0.05 mm, in particular a thickness of 0.05-0.03 mm. This has the advantage that the membrane allows for good sound transmission in a structurally simple manner. A modulus of elasticity of the membrane can particularly preferably be between 1.5 and 4

GPA, in particular 1.7 - 3.5 GPA. This range is particularly advantageous for flexibility and tensile strength of the membrane.

The layer or layers of the membrane can be sized and shaped according to the

requirement of the desired application can be selected. To ensure the fulfillment of

Protection classes IP69 or IP69K, it is advantageous to position the membrane with an accuracy of at least 0.1 mm relative to the sound opening.

In a special embodiment, the sound transducer device can have a membrane with at least one adhesive layer, with at least one adhesive layer connecting the membrane to the substrate, in particular the control device. This has the additional advantage that the sound transducer device has a particularly simple design. The at least one adhesive layer can preferably form an adhesion area of the membrane with the substrate.

Particularly preferably, the membrane can have no adhesive layer in a sound-transmitting area of the membrane. This has the additional advantage that the basis weight of the

Membrane is reduced in this area compared to an embodiment in which the sound-receiving area of the membrane has an adhesive layer. This is advantageous with regard to sound transmission through the membrane.

In one embodiment, the membrane can be concave or convex or flat, with the concave, convex or flat part of the membrane covering the sound-transmitting area of the

Membrane includes. A concave or convex configuration of the membrane, in particular the

Top layer, improves the acoustic sensitivity of the transducer device. The acoustic sensitivity depends on the area and geometry of the sound-transmitting

area the area off. As a result, the sound transducer device can be designed in a structurally simple manner in an optimized manner depending on the desired properties.

8LU500838

With a convex configuration of the membrane, in particular the top layer, the

Spacer layer have a cavity cross-section that is larger than that

switching opening cross-section. If several spacer layers are provided, the

Increase cavity cross-section of the spacer layer in a direction from the substrate to the cap layer. This means that the individual spacer layers have different cavity cross sections. With a convex configuration of the membrane, a part of the membrane that has the sound-transmitting region protrudes from the remaining part of the membrane in a direction away from the substrate.

In a particular embodiment, a sound channel course between the end of the

Sound transducer end facing and the other end of the sound channel, which faces the membrane, not be constant. In particular, the sound channel along the

Have thickness direction of the substrate changing cross-section. The

Narrow the cross section of the sound channel along the thickness direction of the substrate. In particular, the course of the cross section can decrease starting from the other end of the sound channel in the direction of the end of the sound channel, ie in the direction of the sound transducer.

The course of the cross section can be axisymmetric, in particular conical, concave, funnel-shaped and/or step-shaped axisymmetric. Alternatively, the

Cross-sectional constriction also not be axisymmetric. It is particularly advantageous if the cross section narrows, starting from the membrane in the direction of the sound transducer. As a result, an increase in pressure is achieved within the sound channel, what the

Improved the sensitivity of the transducer device. In particular, such a

Design is advantageous in which the sound opening and thus the membrane surface used for sound transmission is not large, and thus little sound energy is transmitted into the sound channel. However, the sound opening and the membrane area cannot be enlarged at will, because in this case the acoustic space has to be reduced in order to obtain a predetermined resonance frequency range. However, reducing the acoustic space is not always possible.

The sound channel can have at least two sections, with a first section having a cross section that changes along the thickness direction. In particular, the cross section decreases in a direction starting from the membrane towards the

sound transducer. A second section, which can directly adjoin the first section, can have a constant cross section. The second section can be directly connected to the sound transducer.

In this case, an area ratio of an area of the other end of the sound channel, the

Membrane is facing, to a surface of the end of the sound channel, which has to the sound transducer (2), between 1.5 and 10, preferably between 3 to 8, in particular 6.25. Included

9 LU500838 the area of the other end of the sound channel can correspond to an area of the sound port. The end of the sound channel facing the transducer opens into the

Interior of the transducer.

In a further embodiment of the sound transducer device, a sound channel medium can have the same or different density than an external medium, in particular air, or can form a different phase. This has the additional advantage that the sound is additionally received in an optimized manner by the sound transducer, since there are no or only small

phase losses occur. Such losses are caused by the phase transition between different media (gas, membrane, gas, sound transducer). The sound channel medium can preferably be air or a non-compressible liquid, in particular an oil, in particular a

mineral oil, have or be.

According to a further aspect of the invention, a method for producing a sound transducer device according to the invention comprising a substrate and a sound transducer which is acoustically connected to one end of a sound channel of the substrate, characterized in that the switching device has a watertight acoustic membrane which another end of the Covering sound channel provided, comprising a step of

Arrangement of the membrane on the substrate, the membrane covering a sound channel of the substrate.

The method can optionally have a further step in which the sound transducer is connected to a side of the substrate opposite the membrane. The method according to the invention can optionally include the step that the membrane is arranged, in particular fastened, on the substrate by means of at least one adhesive layer.

The method according to the invention can optionally include the step that the membrane is arranged, in particular fixed, on the substrate by means of a reflow method. Optionally, the method according to the invention can have a further step in which the at least one cover layer is applied to at least one spacer layer.

The inventive method can optionally include a step in which a

Surface of the membrane is provided with at least one adhesive layer, in particular the entire surface of the membrane. Alternatively, the at least one adhesive layer can be applied in such a way that a predetermined area of the membrane is free of the adhesive layer, in particular a sound-transmitting area of the membrane.

In addition or as an alternative, the method according to the invention can have a step in which the at least one adhesive layer is applied in an adhesion area of the membrane, in particular is applied in a ring shape.

10LU500838

Additionally or alternatively, the method according to the invention can have a step in which the at least one adhesive layer in time before a composition step

membrane is applied.

In addition or as an alternative, the method according to the invention can have a step in which the at least one adhesive layer is applied in a predetermined amount, in particular, for example, to set a predetermined signal-to-noise ratio

sound transducer device.

According to a further aspect of the invention, a position determination device is provided, comprising a sound transducer device according to the invention.

According to a further aspect of the invention, an inventive

Sound transducer device or a position determination device in a motor vehicle, in particular for autonomous driving, and/or in a communication system and/or in a microphone application and/or in an industrial application and/or in

Applications for collision avoidance and / or devices for presence detection are used.

The position determination device can be used for one-dimensional or multi-dimensional, preferably three-dimensional, position determination. Several sound transducer devices can be used to determine the position. One can

Sound transducer device act as a transmitter. In addition, at least one, in particular exactly three, sound transducer devices can act as receivers.

The transmitter and a receiver or two can be used for three-dimensional position determination

Receiver lie on a straight line. The third receiver is arranged in such a way that it is not arranged on the straight line. The sender and all receivers are in one plane

straight has. The object whose position is to be determined is arranged such that it is spaced apart from the plane. In other words, the object is not arranged in the plane. The transmitter can act as one of the receivers after sending out the transmission signal. This means that the transmitter can both transmit the broadcast signal and receive signals.

The subject matter of the invention is shown schematically in the figures, with identical or similarly acting elements generally being provided with the same reference symbols.

Figures 1A-B show a schematic representation of a sound transducer device according to a first embodiment.

Figures 2A-B show a schematic representation of a sound transducer device according to a second embodiment.

Figures 3A-B show a schematic representation of a sound transducer device according to a third embodiment.

Figures 4A-B show a schematic representation of a sound transducer device according to a fourth embodiment.

Figures 5A-B show a schematic representation of a sound transducer device according to a fifth embodiment.

Figures 6A-B show a schematic representation of a sound transducer device according to a sixth embodiment.

Figures 7A-B show a schematic representation of a sound transducer device according to a seventh embodiment.

Figure 8A-B show a schematic representation of a sound transducer device according to an eighth embodiment.

Figures 9 shows a schematic representation of a sound transducer device according to a ninth embodiment.

Figures 10 shows schematically the operation of an inventive

sound transducer device.

FIGS. 1A-B show a sound transducer device 1. FIG. 1B shows a highlighted detail 25 from FIG

Sound transducer 2, which is acoustically connected to one end 16 of the sound channel 12 of a substrate 17. The transducer 2 has a transducer housing 28 and a

Sound receiver and / or transmitter 3, which is arranged in an interior space 19 of the sound transducer 2. The interior space 19 is delimited by the sound transducer housing 28 and the substrate 17 . The sound converter 2 is arranged below the substrate 17 in the installation direction E of the sound converter device 1 .

The sound channel 12 has another end which includes a sound opening 4, where

Acoustic pressure waves pass through the acoustic opening 4 before they reach the acoustic transducer 2, which will be described in more detail below. The sound channel 12 extends through the

12 LU500838 total thickness of the substrate 17. The extent of the substrate 17 between a substrate side facing the environment and a side facing the sound transducer 2 is used as the thickness

substrate side understood. The thickness corresponds to the extension of the substrate 17 along the z-direction of the coordinate system shown in Fig. 1A and/or an extension between the end 16 and the inlet opening 4.

The transducer device 1 has a waterproof acoustic membrane 5, which the

Sound channel 12 covers. In particular, the membrane 5 covers the sound opening 4 . The membrane 5 is arranged on a side directed towards an environment of the substrate 17 and comprises a cover layer 6 and an adhesive layer 11, the adhesive layer 11, the cover layer 6 of the

Membrane 5 completely covered. The membrane 5 is arranged, in particular glued, on the substrate 17 by means of the adhesive layer 11 . The substrate 17 is, for example, a

Control device, such as a printed circuit board. The membrane 5 has two areas, a sound-transmitting area 23 and an adhesion area 24. The sound-transmitting area 23 is the portion of the membrane 5 that when the

Membrane 5 vibrates with a sound wave, so that sound energy is transmitted into the sound channel 12. As can be seen from FIGS. 1A and 1B, the sound-transmitting area is arranged in the area of the sound channel 12 . In particular, a cross section of the sound-transmitting area can correspond to a sound opening cross section 9 .

The sound transducer device 1 also has an acoustic space 18 . The acoustic

Room 18 is a closed room composed of the interior space 19 of the sound transducer 2 and the sound channel 12 . A resonance damping behavior of

Sound transducer device 1 depends on the thickness of the membrane 5 and the sound-transmitting

Area 23 of the membrane 5 existing adhesive layer 11 from. A resonance frequency behavior, in particular a resonance frequency range, of the sound transducer device 1 depends on the volume of the acoustic space 18 . An acoustic sensitivity of the sound transducer device 1 depends on the area and the geometry of the sound channel 12 located in the area

Top layer 6.

FIGS. 2A-B show a second embodiment, only the differences from the first embodiment being discussed below. The second embodiment differs from the first embodiment in that the membrane 5 in the sound-transmitting area 23 has no

Adhesive layer 11 has. As a result, the mass of the sound-transmitting area 23 of the

Acoustic transducer device 1 reduced.

Since there is no adhesive layer 11 on the sound transmitting portion 23 in the embodiment, the resonance damping performance of the acoustic space 18 depends on the thickness of the

Membrane 5 off. The resonance frequency behavior, in particular a resonance frequency range, depends on the volume of the acoustic space 18 . The acoustic sensitivity of the

13 LU500838

Sound transducer device 1 depends on the area and the geometry of the sound-transmitting area 23.

Figures 3A-B show a third embodiment. The third embodiment differs from the first embodiment shown in FIGS. 1A-B in the design of the membrane 5

Spacer layer 7, on which the cover layer 6 is arranged by means of an adhesive layer 11.

In particular, the cover layer 6 is firmly connected to the spacer layer 7 by means of the adhesive layer 11 . The adhesive layer 11 is evenly distributed over the entire underside of the cover layer 6 . The spacer layer 7 is arranged on the substrate 17 and by means of another

Adhesive layer 11 firmly connected to the substrate 17. As a result, the spacer layer 7 is z-

Seen direction between the cover layer 6 and the substrate 17 arranged.

The spacer layer 7 differs from the cover layer 6 in that it has a cavity 10 in the area of the sound opening 4 . The cavity 10 is arranged coaxially with the sound channel 12 . In contrast, the cover layer 6 has the sound-transmitting area 23 in the area of the sound opening 4 . Such a design of the spacer layer 7 leads to the volume of the acoustic space 18 being reduced by that compared to the first embodiment

Volume of the cavity 10 is larger.

Analogously to the first embodiment shown in Figures 1A, 1B, this depends

Resonance damping behavior of the acoustic space 18 on the thickness of the cover layer 6 in z-

Direction and the applied adhesive layer 11 from.

Figures 4A-B show a fourth embodiment. The fourth embodiment differs from the third embodiment in the design of the membrane 5, in particular the cover layer 6 and the spacer layer 7. The cover layer 6 is concave in the area of the sound opening 4. FIG. The concave part of the cover layer 6 encompasses the sound-transmitting part

Area 23. The spacer layer 7 has a cavity 10 in the area of the sound opening 4, the cross section of which is larger than the sound opening cross section 9. Due to the concave

Formation of the cover layer 6 resulting concave depression 22 has a favorable effect on the acoustic sensitivity of the sound transducer device 1. As already explained above, the acoustic sensitivity of the acoustic transducer device 1 depends on the area and the

Geometry of the top layer 6 located in the area of the sound channel 12.

Figures 5A-B show a fifth embodiment. The fifth embodiment differs from the fourth embodiment in the attachment of the adhesive layer 11 to the cover layer 6.

Although the adhesive layer 11 is evenly distributed on the underside of the cover layer 6, there is a difference in that the adhesive layer 11 in the area of the sound opening 4 as a

14 LU500838 circular ring. This ensures a permanent connection.

The application of the adhesive layer 11 on the layers of the membrane 5 takes place before

assembly and serves to form stronger and lighter assemblies.

Figures 6A-B show a sixth embodiment. The sixth embodiment differs from the third embodiment illustrated in FIGS. 3A, 3B in the design of the

Membrane 5. The membrane 5 thus has two spacer layers 7 which are arranged one above the other and are fastened to one another by means of an adhesive layer 11. In this case, the spacer layer 7 that is further away from the substrate 17 has a larger cavity cross section than that on the

Substrate 17 arranged spacer layer 7. This allows the cover layer 6 in the region of the sound channel 12 is concave.

The cover layer 6 is firmly connected to the spacer layer 7 applied directly to the substrate 17 by means of an annular adhesive layer 11 . The sound-transmitting area 23 of the membrane 5 covering the sound opening 4 has no adhesive layer 11 .

Figures 7A-B show a seventh embodiment of a sound transducer device 1. The seventh

Embodiment differs from the sixth embodiment in the formation of

Membrane 5. Thus, the seventh embodiment has a total of five spacer layers 7, while the sixth embodiment has two spacer layers 7.

Two spacer layers 7 are formed in such a way that their respective cavity 10

Volume of the acoustic space 18 increased. In particular, the

Cavity cross section of the respective spacer layer 7 corresponds to the sound opening cross section 9. These are the two spacer layers that are assigned closer to the substrate 17 than the remaining spacer layers 7. The remaining spacer layers have a

Cavity cross section which is larger than the sound opening cross section 9. The cavity cross section increases along a direction from the substrate 17 towards the

Top layer 6.

In the present embodiment, since three spacer layers 7 differ in cavity cross-section from hole cross-section, the concave recess 22 of the cover layer has a larger volume than the concave recess 22 of the sixth embodiment.

Another difference is that there is no annular adhesive layer 11 that

Top layer 6 with a spacer layer 7 connects. The adhesive layer 11 is evenly distributed over the entire cover layer 6, with the exception of the sound-transmitting area 23.

15LU500838

The acoustic space 18 is larger in the seventh embodiment than in the sixth embodiment.

This results from the fact that there are two spacer layers 7, each with a cavity 10, whereas in the sixth embodiment there is one spacer layer 7, the cavity 10 of which forms the volume part of the acoustic space 18.

Figures 8A-B show an eighth embodiment. The eighth embodiment differs from the third embodiment in the formation of the membrane 5. In particular, the

Cover layer 6 in the area of the sound opening 4, ie at least one of the sound-transmitting

Region 23 comprising part of the membrane 5, a convex shape. This is made possible by the application of additional adhesive layers 11 to the layers of the membrane 5 and / or the application of annular adhesive layers 11, each of the top layer 6 with the

Connect spacer layer 7 firmly. Due to the convex design of part of the membrane 5, the acoustic space 18 increases in comparison to the third embodiment shown in FIGS. 3A, 3B.

The convex formation of the top layer 6 can be done in that the assembly of

Sound transducer device 1 takes place under high pressure. It is therefore possible to create convex shapes by assembling the acoustic transducer device under high air pressure.

The air trapped in the sound duct 12 expands in the normal atmosphere and forms convex bubbles.

A sound transducer device 1 designed in this way enables better sensitivity for

Sound pressure waves arriving at a steep angle.

FIG. 9 shows a ninth embodiment. The ninth embodiment differs from the first

Execution in the formation of the sound channel 12. Thus, the sound channel 12 in the ninth

Execution two sections. A first section, which extends from the sound opening 4 in the direction of the sound transducer 2, has a cross section that decreases along a thickness direction of the substrate. The cross section refers to a plane that leads to the z

direction is normal. In contrast, a second section directly adjoining the first section has a constant cross section along the thickness direction. The second section thus extends from the transition area with the first section to the end 16 of the

Sound channel 12. An area ratio of an area of the sound opening 4, which corresponds to an area of the other end of the sound channel 12, to an area of the other end 16 of the

Sound channel 12 is between 1.5 and 10, in particular 6.25.

Figure 10 shows schematically how a sound transducer device 1 works. In Figure 10, the cover layer 6 of the membrane 5, in particular the sound-transmitting area 23

16 LU500838 part of membrane 5, concave. However, each of the previously described sound transducer devices 1 has the mode of operation described below.

Sound pressure waves 27 from the surroundings of the sound transducer device 1 impinge on the membrane 5, which causes the membrane 5, in particular the sound-transmitting region 23, to vibrate. This is symbolized in FIG. 10 by the double arrow. In other words, the

Pressure energy of the sound pressure waves is transferred into kinetic energy of the membrane 5 . The sound energy transmitted to the membrane 5 is transmitted into the sound channel 12 .

A distinction must be made with which sound channel medium 13 the sound channel 12 is filled. In the event that the sound channel 12 is filled with a compressible fluid such as air, 5 sound pressure waves are generated in the sound channel 12 by the vibration of the membrane, the

Pass sound channel 12 and get into the interior 19 of the transducer 2 and from which

Sound receiver 3 are detected.

In the event that an incompressible fluid, such as a liquid, is arranged in the sound channel 12, the vibration of the membrane 5 is directly in the sound transducer 2, in particular the

Sound receiver 3 transmitted. In the embodiment shown in Figure 10 is a

Liquid arranged in the sound channel 12, which is symbolized by the gray shading of the sound channel 12.

17LU500838

REFERENCE LIST

1 sound transducer device 2 sound transducer 3 sound receiver and/or transmitter 4 sound opening 5 membrane 6 cover layer 7 spacer layer 9 sound opening cross section 10 cavity 11 adhesive layer 12 sound channel 13 medium 16 end of sound channel 17 substrate 18 acoustic space 19 inner space 22 concave depression 23 sound transmitting area 24 adhesion area highlighted area 27 Sound pressure waves 28 Sound converter housing 25 E Installation direction

Claims (30)

18 LU500838 CLAIMS 1. Sound transducer device (1) comprising a substrate (17) and a sound transducer (2), which is acoustically connected to one end (16) of a sound channel (12) of the substrate (17), characterized in that the switching device (1) has a waterproof acoustic membrane (5) covering another end of the sound channel (12). 2. Sound transducer device (1) according to claim 1, characterized in that the substrate (17) has or is a control device or a printed circuit board. 3. Sound transducer device (1) according to claim 1 or 2, characterized in that a. the membrane (5) is firmly connected to the substrate (17) and/or that b. the membrane (5) is arranged, in particular glued, on the substrate (17). 4. Sound transducer device (1) according to any one of claims 1 to 3, characterized in that the other end of the sound channel (12) comprises a sound opening (4). 5. Sound transducer device (1) according to claim 1 to 4, characterized in that the sound transducer (2) and the membrane (5) are arranged on opposite sides of the substrate (17). 6. Acoustic transducer device (1) according to claims 1 to 5, characterized in that the acoustic transducer device (1) is configured such that an acoustic pressure wave passes through the acoustic channel (12) before being received by the acoustic transducer (2). 7. sound transducer device (1) according to claim 1 to 6, characterized in that a. the membrane (5) closes off an acoustic space (18) composed of the sound channel (12) and an interior space (19) of the sound transducer (2), and/or that b. an acoustic space (18), which is composed of the sound channel (12) and an interior (19) of the sound transducer (2), is completely closed off by the membrane (5) and a sound transducer housing (28). 8. sound transducer device (1) according to claim 1 to 7, characterized in that a. the sound transducer (2) has an interior space (19) which is at least partially enclosed by a sound transducer housing (28) and is acoustically connected to the sound channel (12), and/or that b. the sound converter (2) has a sound receiver and/or transmitter (3) which is arranged in an interior (19) of the sound converter (2). 19LU500838 9. Sound transducer device (1) according to claim 1 to 8, characterized in that the membrane (5) a. comprises or is formed from a polyimide, in particular a thermosetting polyimide, in particular poly(4,4'-oxydiphenylene-pyromellitimide); and/or b. comprises or is formed from a polyester, in particular a biaxially oriented polyester, in particular a biaxially oriented polyethylene terephthalate, and/or c. impermeable to air and/or coatable, in particular paintable, and/or pressure-resistant, in particular up to a pressure of 10,000 kPa and/or temperature-resistant in a temperature range from -269 °C to 400 °C, in particular in a temperature range from -70 °C to 150 °C, in particular in a temperature range from -40 °C to 100 °C. 10. Sound transducer device (1) according to any one of claims 1 to 9, characterized in that the membrane (5) a. has a cover layer (6) and/or b. has at least one spacer layer (7) and/or c. Has at least one adhesive layer (11). 11. Sound transducer device (1) according to claim 10, characterized in that a. the cover layer (6) is arranged on at least one spacer layer (7) and/or adhesive layer (11), and/or b. the cover layer (6) has an adhesive layer (11), in particular an annular adhesive layer (11), and/or c. the at least one spacer layer (7) has a cavity (10) which is fluidically connected to the sound channel (12), and/or d. the at least one spacer layer (7) has an adhesive layer (11), in particular an annular adhesive layer (11). 12. Sound transducer device (1) according to any one of claims 1 to 11, characterized in that the membrane (5) has a thickness of 0.01 to 0.1 mm, in particular a thickness of 0.02 to 0.05 mm, in particular a thickness of 0.05 — 0.03 mm. 13. Sound transducer device (1) according to one of claims 1 to 12, characterized in that a modulus of elasticity of the membrane (5) is between 1.5 and 4 GPA, in particular between 1.7-3.5 GPA. 14. Sound transducer device (1) according to any one of claims 1 to 13, characterized in that an area ratio of an area of the other end of the sound channel 20 LU500838 (12) facing the membrane (5) to an area of the end of the sound channel (12) facing the sound transducer (2) is between 1.5 and 10. 15. Sound transducer device (1) according to one of claims 1 to 14, characterized in that the membrane (5) has at least one adhesive layer (11), the at least one adhesive layer (11) connecting the cover layer (6) to the substrate (17) and/or connecting the spacer layer (7) and/or connecting the spacer layer (7) to the substrate (17). 16. Sound transducer device (1) according to claim 15, characterized in that the at least one adhesive layer (11) forms an adhesion area (24) of the membrane (5). 17. Sound transducer device (1) according to claim 15 or 16, characterized in that the membrane (5) has no adhesive layer (11) in a sound-transmitting region (23). 18. Sound transducer device (1) according to claim 15 to 18, wherein the at least one adhesive layer (11) is arranged annularly around the sound opening (4). 19. Sound transducer device (1) according to one of claims 1 to 18, characterized in that the membrane (5), in particular a sound-transmitting area (23) of the cover layer (6), is concave or convex or flat. 20. Sound transducer device (1) according to any one of claims 1 to 19, characterized in that a. a cross section of the sound channel (12) changes along a thickness direction of the substrate (17) and/or b. the sound channel (12) has two sections, a first section having a cross-sectional constriction along the thickness direction of the substrate (17), and a second section having a constant cross-section along the thickness direction of the substrate. 21. Sound transducer device (1) according to one of claims 1 to 20, characterized in that a sound channel medium (13) has a density which is the same as or different from an external medium or forms a different phase. 22. Sound transducer device (1) according to claim 24, characterized in that the sound channel medium (13) a. is air, isn't it 21 LU500838 b. has or is a liquid, in particular a non-compressible liquid, in particular an oil, in particular a mineral oil. 23. A method for producing a sound transducer device (1) according to any one of claims 1 to 22, comprising a step of arranging a membrane (5) on a substrate (17), the membrane (5) having a sound channel (12) of the substrate (17 ) covers. 24. The method of claim 23; characterized in that the method comprises a step in which an acoustic transducer (2) is connected to a side of the substrate (17) opposite the membrane (5). 25. The method according to claim 23 or, characterized in that the cover layer (6) and/or the spacer layer (7) is arranged, in particular fastened, on the substrate (17) by means of at least one adhesive layer (11). 26. The method as claimed in claims 23 to 25, characterized in that the membrane (5) is arranged, in particular fastened, on the substrate (3) by means of a reflow process. 27. The method according to claim 23 to 26, characterized in that the cover layer (6) is applied to at least one spacer layer (7). 28. The method according to claim 23 to 27, characterized in that a. a surface, in particular the entire surface, of the cover layer (6) and/or the spacer layer (7) is provided with at least one adhesive layer (11), and/or b. the at least one adhesive layer (11) is applied in such a way that a predetermined area of the membrane (5) is free of the adhesive layer (11), in particular a sound-transmitting area (23) of the membrane (5), and/or c. the at least one adhesive layer (11) is applied in an adhesion area (24) of the membrane (5), in particular applied in a ring shape, and/or d. the at least one adhesive layer (11) is applied before an assembly step of the membrane (5), and/or e. the at least one adhesive layer (11) is applied in a predetermined quantity. 29. Position determination device having at least one sound transducer device (1) according to one of claims 1 to 22. 22 LU500838 30. Use of a sound transducer device (1) according to any one of claims 1 to 22 or a position determination device according to claim 29 for one-dimensional or multi-dimensional, preferably three-dimensional, position determination.