WO2010031612A1

WO2010031612A1 - Apparatus for producing wideband sound in the audible range of humans

Info

Publication number: WO2010031612A1
Application number: PCT/EP2009/059243
Authority: WO
Inventors: Robert Bösnecker
Original assignee: Siemens Aktiengesellschaft
Priority date: 2008-09-17
Filing date: 2009-07-17
Publication date: 2010-03-25
Also published as: DE102008047796A1

Abstract

The invention relates to an apparatus for reproducing sound. The invention is based on the object of specifying a loudspeaker based on the transverse wave principle which is capable of exciting even the low-frequency portion of the human audible range. This object is achieved by an apparatus for reproducing sound by means of at least one film which can be excited at least to some extent to produce transverse-wave-like oscillations, wherein the transverse-wave-like oscillations can be coupled into the film at at least one excitation point by means of at least one electromechanical transducer which can be used to convert electrical sound signals into mechanical oscillations. In this context, a film is understood to mean a material which is flexible and/or can be wound up and/or can be rolled up and which retains this property at least to some extent permanently.

Description

description

Device for generating broadband sound in the audible range of humans

The invention relates to a device for reproducing sound.

Such a device is used to generate acoustic events such as speech, music, warning sounds and / or frequencies or frequency mixtures that can be perceived, for example, by humans at least partially with the ears.

From the prior art u.a. the following devices for the generation of acoustic events known: For the generation of acoustic events piston-stroke speakers are used in general. These move air back and forth, creating air pressure fluctuations. These fluctuations propagate spherically from the speaker. If the fluctuation frequencies are within the range of the human hearing range, they are perceived as an acoustic event.

Another form of air stimulation has been known since the 1920's under the name Blatthaller. This loudspeaker invented by Walter Schottky at Siemens in Berlin works on the principle of a vibrating surface.

The works of Warnaka have been known since the 1960s. Like Schottky, it uses rigid membranes that can not be unwound.

Since the 1990's the works of H. Azima and the company nxt are known. Here are also rigid

Membranes used that must be so stiff that they are able to form resonances. The works of Josef Manger have been known since the 1980s. This uses a non-heterogeneous membrane to make a sound generator by means of a bending wave excitation mechanism. The Manger membrane is thinner in the middle and thickens towards its edges. The drive device is located between the thinnest and the thickest point of the membrane. Thus arise in the so-called Manger converter, the high frequencies intentionally within the drive device, the middle frequencies arise outside. The Manger converter does not generate any deep frequencies at all, which is why it always has to be operated in conjunction with a woofer in order to obtain a usable sound image.

In order to obtain the radiation behavior desired by Manger, the membrane is designed point-symmetrical, usually it has symmetrically distributed tips or lobes, which should ensure a uniform spectrum. The membrane is often shaped like a symmetrical star.

Other patents cited in the prior art indicate that the transverse shaft principle is well known. Speakers that use this principle have a mostly plate-shaped membrane. This can be flat or curved. By an appropriate drive the membrane surface is excited to vibrations. These vibrations stimulate the air surrounding the membrane to vibrate. If the vibration frequencies are in the audible range, they are perceived as an acoustic event. The sound-generating principle is thus based on a planar-shaped membrane that vibrates.

In contrast, so-called longitudinal wave generators are used in most of the speakers used so far. For example, a longitudinal wave generator works like a conventional piston-stroke loudspeaker. A mostly cone-shaped membrane is stimulated by an electrically amplified audio signal to move back and forth on an axis, thus avoiding an acoustic image of the audio signal. at least partially to produce. The sound waves generated by this loudspeaker are aligned in the longitudinal direction to it.

A transversal wave generator works like a vibrating surface. By a corresponding drive, which is usually electrodynamic and / or piezoelectric, a surface is excited to vibrate. This vibrating surface now produces a sound wave image that is completely different from the above-mentioned longitudinal waves. This wave pattern is called the transverse wave, because it develops along the sound surface. This principle has been known for example in musical instrument making for centuries.

The invention has for its object to provide a loudspeaker according to the transversal wave principle, which is able to stimulate even the low-frequency part of the human hearing.

This object is achieved by a device for reproducing sound by means of at least one film which is at least partially excitable to transversal wave-like vibrations, wherein the transversal wave-like vibrations by means of at least one electromechanical transducer, with the electrical Tonsignale be converted into mechanical vibrations, at least one Excitation point are in the film einkopel felbar are.

Definition Film: A film is understood below to mean a material which has a certain flexibility and a defined constant thickness at all points.

To determine the flexibility, the following test equipment is used: The film to be used as a membrane surface is clamped and / or clamped at one end or at one edge in a vertical holder. Part of the film is now fixed, the rest of the film is located Free in the room. Now, this holder is tilted by 45 degrees, the inclination is perpendicular to the film surface. Due to its ability to bend, the film will react, which defines whether it is a film. Possible reactions: a.) The test material collapses when it is fixed in the vertical holder. Then it is a soft film, such as cling film. b.) When fixing in the vertical holder, the test material is also still vertical, but at 45 degrees inclined holder tilts the test material, however, so that their opposite end of the holder differs by more than 5 degrees from the 45 degrees. Then it is a hard film, such as a plastic sheet. c.) When fixing in the vertical holder, the test material is vertical and the 45 degrees inclined holder, the opposite end of the holder tilts by less than 5 degrees difference. Then it is not a foil but a little or no flexible plate, such as a honeycomb plate or a gypsum fiber board or a metal plate, etc.

It must also be noted that the original size of the test material is used for the test in which it is used as a membrane film. If, for example, a foil with a size of 80cm x 70cm is stimulated to vibrate, an 80cm x 70cm foil must be used for the test of the foil property by means of the above tests. It may well happen that a very small piece (for example, 10cm x 10cm) of a material X does not give a film in the above sense, but a large, long piece (for example, 10cm x 120cm) of the same material X very well a film in the above sense can be. In the following, a film is understood as meaning a material which is flexible and / or windable and / or rollable, and which at least partially permanently maintains this property.

The inventively executed device generates by vibration of a film, a movement of the surrounding air. The vibration inducing vibratory vibration generator is capable of generating vibration frequencies that are at least partially within the human hearing range. This can be high frequencies, but also very low frequencies. The device preferably generates transverse waves. Since special films in this disclosed device are particularly well suited to producing low frequencies, this can eliminate the use of a conventional woofer (subwoofer), which entails a significant cost advantage in providing a broadband system. The films used herein are electrically neutral, i. they carry no tensions and / or currents and are harmless to humans.

Furthermore, the device has any geometric shape, which stimulates the surrounding air to vibrate by vibration. Above all, it is able to stimulate the low-frequency part of the human hearing range. This avoids the use of a woofer.

Differentiation to the state of the art:

Prior Art:

DE 2003950 Al Oskar Heil 19.02.1969

In this patent, a device is disclosed in which a film is used as a speaker diaphragm.

The film is folded over a large number of plus and minus poles and has an electrical conductivity. If it flows through a signal current, it moves in the magnetic field of the poles. Differentiation to this disclosure: First, the film is folded.

Second, it is provided with electrical conductivity. Third, no transverse waves are generated. Furthermore, this principle is not suitable for generating medium and low frequencies. Loudspeakers that work according to this principle require an additional woofer.

US 3,345,469 R.L. Rod 02.03.1964

This document discloses a device for using a foil to build an electrostat. In this case, a film which reacts to an electric field is brought into an electrostatic field. The foil hovers between two planar poles. The floating voltage in practice is 8000 to 12000 volts and harms the human sustainably, should he come into contact with this voltage. The signal to be transmitted is then added to this high voltage and causes the entire film moves and thus generates an acoustic event.

Differentiation to this disclosure: First, the film is electrically influenced. Second, no transverse waves are generated. Third, the voltages used are very harmful to health.

Furthermore, this principle is not suitable for generating low frequencies. Speakers working on this principle need an additional woofer.

DE 3542458 R. Görike 30.11.1985

This document discloses an apparatus for constructing a film for constructing a large area electrostatic charge. The drive principle corresponds to that of US 3,345,469 and thus has nothing in common with this disclosure here. WO 9956498 K. Kirjavainen 04.11.1999

In this patent a device is disclosed how to construct a large-area loudspeaker by means of an electrically conductive or rechargeable foil. The drive principle is similar to that of an electrostat. Differentiation to this disclosure:

First, the foil is electrically rechargeable, or second, it is provided with electrical conductivity. Third, no transverse waves are generated.

EP 0592570 Bl. Bientz 25.03.1992

This patent describes a telephone handset in which the sound generation is to take place by means of piezoelectric excitation. In this case, "... the electro-acoustic converter is formed by a carrier foil which contains a sound membrane, wherein the piezoelectric element is fastened on the carrier foil, the carrier foil also contains conductor paths ..." Delineation to this disclosure: It becomes a carrier foil The excitation does not take place at the sound membrane, Second, piezoelectric exciters can not produce low frequencies The teaching of this patent relates to telephone applications and not to woofer reproduction.

EP 0590799 B1 B. Cherek 01.09.1993

In this patent a plate excited to transverse vibration is described. A behind the plate located film and an adjoining sound killing material are obviously not for sound production, but for damping. Differentiation to this disclosure:

It is a sound plate used for sound production and no foil.

DE 2236374 C J. Manger 25.07.1972

In this patent, membrane property for a

Speaker described. This patent builds from this Speaker diaphragm by means of the known cone speaker technology a sound generator. Differentiation to this disclosure:

First, a speaker diaphragm rather than a foil is used as the sound-emitting element.

Second, no transverse waves are generated.

As can be seen in the examples given in the prior art, in some cases a rigid plate and / or an electrically active (metal) foil have already been used. However, the teaching disclosed herein of a swinging foil reaching down to the bass has not occurred before.

Advantageous embodiments of the invention are specified in the subclaims.

An embodiment according to the invention is advantageously designed such that at least one film-like surface of constant thickness is at least partially excited to transverse-wave-like vibrations. This is another difference to the so-called Manger transducer, in which the membrane is made thinner in the middle. This also allows the construction of very inexpensive membranes, since the thickness does not have to be varied.

An embodiment according to the invention is advantageously designed such that the desired frequencies lie outside the at least one excitation point. In contrast to the Manger converter, the device disclosed here differs in that the high frequencies occur not only inside but above all outside the drive device (the electromechanical converter). To realize this with the film, the drive elements are designed so that they are punctiform and / or almost point-shaped. Almost point-like means that the wavelengths of the high frequencies are greater than the physical extent of the drive point. The driving point of the For example, drive elements can be as large as a screw head or like a coin.

An embodiment according to the invention is advantageously designed such that the surface is at least partially not transparent.

An embodiment according to the invention is advantageously designed such that at least one film-like surface is at least partially clearly specular and / or diffusely reflecting.

An embodiment of the invention is advantageously designed such that at least one sheet-like surface is at least partially wound up. This film can be at least partially wound up when not in use. This film may also be at least partially unwound for use. This embodiment of the invention now combines the properties of a windable film with the area of sound.

An embodiment according to the invention is advantageously designed such that at least one foil-like surface is fixed on at least one fixed frame. In order to ensure sufficient stability during use, so the film can be supported by means of an example frame-like construction.

An embodiment of the invention is advantageously designed such that at least one of the vibration exciter works according to the electrodynamic principle, that is, that it at least partially converts electrical signals into a corresponding movement.

An embodiment of the invention is advantageously designed such that at least one of the vibration exciter is located exactly in the middle and / or near the middle of the film. An embodiment of the invention is advantageously designed such that at least one of the vibration exciter, which is located exactly in the middle and / or near the middle of the film for the reproduction of the low frequencies is at least partially used.

An embodiment according to the invention is advantageously designed such that at least one part of the film is used for image projection and / or for displaying images and / or symbols and / or advertisements and / or warnings and / or mandatory signs and / or prohibition signs and / or information signs becomes. At least one film is flat in the operating state and / or even and / or wrinkle-free and is therefore also suitable as a projection surface.

An embodiment according to the invention is advantageously designed such that at least one of the vibration exciter reproduces an acoustic signal which runs synchronously or with a time delay in synchronism with an image reproduction and / or has a content-related relation to the image reproduction. (For example, video, slideshow, emergency announcement, evacuation announcement u.v.m.)

An embodiment according to the invention is advantageously designed such that at least one film-like surface is at least partially resistant to environmental influences such as dirt, dust, mucus, body fluids of any kind, acids, bases, as well as solid, liquid or gaseous pollutants or any mixtures thereof.

An embodiment of the invention is advantageously designed such that at least one sheet-like surface is at least partially washable and / or arbitrarily cleanable.

An embodiment of the invention is advantageously designed such that at least one film-like surface is so robust and / or is stabilized by an auxiliary construction so that it at least one weight at least their own weight (gross weight), wear and / or can withstand.

An embodiment of the invention is advantageously designed such that at least one film-like surface is at least partially self-luminous and / or light emitting and / or backlit and / or the film is illuminated laterally.

An embodiment according to the invention is advantageously designed in such a way that at least one sheet-like surface is at least partially designed to display solid image and / or moving image and / or information.

An embodiment of the invention is advantageously designed such that at least one film-like surface is at least partially not plan formed, but for example, is three-dimensionally shaped (concave, convex, etc.).

An embodiment of the invention is advantageously designed such that the sound-emitting unit consists of more than one sheet-like surface, and thus volume and / or sound spectrum and / or phase behavior and / or radiation behavior can be determined by appropriate combination.

An embodiment of the invention is advantageously designed such that the sound-emitting unit consists of more than one sheet-like surface, which are arranged at a distance from each other and the space consists of a matter other than air.

An embodiment of the invention is advantageously designed such that the sound-emitting unit consists of more than one sheet-like surface, which are arranged at a distance from each other and the gap with an acoustically active matter such as oil and / or foam and / or granules. An embodiment according to the invention is advantageously designed in such a way that the sound-radiating unit consists at least partially of a biodegradable and / or environmentally harmless and / or suitable for consumption material and / or a combination of materials, at least one part, for example, at least partially rot and / or is fertile and / or can be recycled.

An embodiment according to the invention is advantageously designed such that at least one sensor (electromechanical transducer) which excites the film-like surface for vibration is fastened only to the film.

An embodiment according to the invention is advantageously designed such that at least one donor-like surface for vibration-inducing donor is not only attached to the film, but is also otherwise supported by an auxiliary construction.

An embodiment according to the invention is advantageously designed such that at least one donor-like surface for vibration-inducing donor differs from at least one other donor in shape and / or geometry and / or weight and / or action principle and / or color and / or attachment. Should a single vibration generator not be able to produce the desired sound spectrum, it is therefore also possible for a plurality of different vibration generators to be arranged on the same film in order to produce the desired spectrum in total.

An embodiment according to the invention is advantageously designed in such a way that at least one donor-like surface for vibration-inducing donors is fixed in a punctiform manner and / or is fixed substantially on a continuous attachment surface. An embodiment according to the invention is advantageously designed in such a way that at least one donor-like surface for vibration-inducing donors is at least partially coupled via a non-punctiform fixation, for example an annular or polygonal or segmental coupling, whereby care is taken by suitable damping that within the Ankoppelungsortes a high-pitch playback is at least partially attenuated.

In the following the invention will be described and explained in more detail with reference to the embodiments illustrated in the figures. Show it:

1 shows a wound film for use in a transverse wave generator,

2 shows a film with vibration exciter and a frame for stabilizing the film.

1 shows a suitable film 1, which is wound up into a roll. To realize the structure referred to below as the "transversal film loudspeaker" (TFL), the film 1 is unwound from the roll, cut to size and prepared for use.

FIG 2 shows the other components: This so processed film 1 is glued to stabilize on a frame 2, which consists for example of wood. The film 1 is still flexible, for example, it can be easily pressed by hand, at least one millimeter. If you were to solve the slide 1 again from the frame 2, so you could roll it up again.

At this slide 1 vibration exciter 4 are now attached. Depending on the application, it may be at least one pathogen 4 or a plurality of pathogens 4. The pathogens 4 can themselves be flexible, but they do not have to. To stabilize the attachment, a piece of a suitable material 3 between exciter 4 and slide 1 can be placed. The vibration exciters 4 are now supplied by at least one signal so that they at least partially produce a perceptible by the listener sound spectrum. Different pathogens 4 can generate different partial spectra, so that only in the sum of all pathogens 4, the desired spectrum forms at least partially.

The film 1 is now excited by the exciters 4 to vibrate and thus at least partially generates the desired sound.

In summary, the invention relates to a device for reproducing sound. The invention has for its object to provide a loudspeaker according to the transversal wave principle, which is able to stimulate even the low-frequency part of the human hearing. This object is achieved by a device for reproducing sound by means of at least one film which is at least partially excitable to transversal wave-like vibrations, wherein the transversal wave-like vibrations by means of at least one electromechanical transducer, with the electrical sound signals are converted into mechanical vibrations, at least one excitation point in the film can be coupled. By foil is meant a material which is flexible and / or windable and / or rollable, and which at least partially retains this property permanently.

Claims

claims

1. A device for reproducing sound by means of at least one film (1) which is at least partially excitable to transversal wave-like vibrations, the transversal wave-like vibrations by means of at least one electromechanical transducer (4), with the electrical sound signals are converted into mechanical vibrations , in at least one point of excitation in the film (1) can be coupled.

2. Device according to claim 1, wherein at least one film (1) has a constant thickness.

3. Device according to claim 1 or 2, wherein desired frequencies of the sound are outside the at least one excitation point.

4. Device according to one of the preceding claims, wherein at least one film (1) is at least partially not transparent.

5. Device according to one of the preceding claims, wherein at least one film (1) is at least partially clear and / or diffuse specular.

6. Device according to one of the preceding claims, wherein at least one film (1) is at least partially wound up.

7. Device according to one of the preceding claims, wherein at least one film (1) is fixed on at least one fixed frame.

8. Device according to one of the preceding claims, wherein at least one electromechanical transducer (4) operates on the electrodynamic principle.

9. Device according to one of the preceding claims, wherein at least one electromechanical transducer (4) is arranged at least substantially centrally on the film (1).

10. The device according to claim 9, wherein at least one of the substantially centrally on the film (1) arranged electromechanical transducer (4) for reproducing low frequencies is at least partially usable.

11. Device according to one of the preceding claims, wherein at least a part of the film (1) is usable for image reproduction.

12. The device according to claim 11, wherein the electrical sound signals of at least one electromechanical transducer (4) are synchronous or time-shifted in synchronism with the image reproduction and / or have a content related to the image reproduction.

13. Device according to one of the preceding claims, wherein at least one film (1) is at least partially resistant to environmental influences.

14. Device according to one of the preceding claims, wherein at least one film (1) is at least partially washable and / or cleanable.

15. Device according to one of the preceding claims, wherein at least one film (1) is so robust and / or stabilized by an auxiliary construction such that it can carry at least a weight that corresponds to its own weight, and / or can withstand such a weight.

16. Device according to one of the preceding claims, wherein at least one film (1) at least partially self-luminous and / or light-emitting and / or light-transmitting and / or is designed such that light can be introduced laterally.

17. Device according to one of the preceding claims, wherein at least one film (1) is formed such that at least partially a solid image and / or a moving image and / or information can be displayed.

18. Device according to one of the preceding claims, wherein at least one film (1) is at least partially not plan formed.

19. Device according to one of the preceding claims, wherein by means of at least two films (1) volume and / or sound spectrum and / or phase behavior and / or radiation behavior are spatially adjustable.

20. Device according to one of the preceding claims, wherein at least two foils (1) are arranged at a distance from one another and a gap between the foils (1) consists of a matter other than air.

21. Device according to one of the preceding claims, wherein at least two foils (1) are arranged at a distance from one another and a gap between the foils (1) consists of an acoustically active matter.

22. Device according to one of the preceding claims, wherein at least one film (1) consists at least partially of a biodegradable and / or environmentally harmless and / or suitable for consumption material and / or a combination of materials thereof.

23. Device according to one of the preceding claims, wherein at least one electromechanical transducer (4) on the

Foil (1) is attached.

24. Device according to one of the preceding claims, wherein at least one electromechanical transducer (4) is at least partially attached to an auxiliary structure.

25. Device according to one of the preceding claims, wherein at least two electromechanical transducers (4) differ in shape and / or geometry and / or weight and / or action principle and / or color and / or fastening.

26. Device according to one of the preceding claims, wherein at least one electromechanical transducer (4) punctiform and / or substantially on a continuous mounting surface (3) on the film (1) is fixed.

27. Device according to one of the preceding claims, wherein at least one electromechanical transducer (4) via a non-point-coupling on the film (1) is fixed, wherein by a suitable damping within the coupling a high-frequency reproduction is at least partially damped.