FR3069746A1 - SOUND TRANSMISSION DEVICE FOR HEADER COMPRISING A MAIN CHANNEL AND AN AUXILIARY CHANNEL - Google Patents

Abstract

A sound transmission device (4) for an earphone (2), having an input opening (41) extending along an input axis, said input opening (41) being adapted to receive a source of sound emission, an output opening (42) adapted to be presented in an ear (1) and a diffusion chamber (40) adapted to conduct the sound towards said outlet opening (42), the diffusion chamber (40) having at least one longitudinal separation wall (9) defining at least one main diffusion channel (6) and an auxiliary diffusion channel (7) of different lengths in the diffusion enclosure (40) so as to create an offset in the transmission of sound to the output aperture (42).

Description

SOUND TRANSMISSION DEVICE FOR EARPHONE WITH A CHANNEL

MAIN AND AN AUXILIARY CHANNEL

GENERAL TECHNICAL AREA AND PRIOR ART

The present invention relates to the field of devices for transmitting sound, in particular music.

A headset is known in the prior art, adapted to be worn on the head, comprising two earphones connected by a hoop which are intended to cover the ears of the wearer of the helmet. These headphones are commonly referred to as closed headphones. Likewise, headphones without a connecting hoop are known which are intended to be positioned directly in one ear. These headphones are commonly referred to as in-ear headphones.

The sound performance of such headphones is not optimal. The sound performance can be determined according to several parameters, in particular, the quality of the treble, the quality of the midrange, the quality of the bass and the spatiality of the sounds emitted. As a reminder, spatiality corresponds to the faculty of sound to be interpreted by the listener's brain as coming from various sources and different locations. For example, when an earpiece is capable of restoring spatiality, the listener hears sound coming from various sources and positioned more or less distant from it. In particular, wood instruments may seem closer to it than copper instruments, which improves the listener's immersion.

In practice, conventional headphones do not have sufficient spatiality since the loudspeaker of the earpiece is very close to the ear of the listener. Some headphones try to reproduce stereo spatiality electronically, but it remains imperfect. Such close positioning can also cause hearing problems.

With reference to FIG. 1, in order to resolve this drawback, it has been proposed by patent application FR3020737A1 a sound transmission device 4 for a headset, comprising an inlet opening 41 extending along an inlet axis, said inlet opening 41 being able to receive a source of sound emission such as a loudspeaker, an outlet opening 42 able to be presented in an ear 1 and a diffusion enclosure 40 able to conduct the upstream sound in downstream from said inlet opening 41 towards said outlet opening 42, said diffusion enclosure 40 comprising, opposite said inlet opening 41, a first vibration wall extending orthogonally to the inlet axis capable of resonate following a sound emission along said input axis. Such a transmission device generates vibrations of the sounds emitted by the sound source, which increases the spatiality.

One of the objectives of the present invention is to provide features of spatiality which offer a listening which seems natural by reinforcing the impression of immersion of the users.

GENERAL PRESENTATION OF THE INVENTION

To this end, the invention relates to a sound transmission device for a headset, comprising an input opening extending along an input axis, said input opening being capable of receiving a source of sound emission, a outlet opening adapted to be presented in an ear and a diffusion enclosure able to conduct the sound from upstream to downstream from said inlet opening towards said outlet opening.

The device is remarkable in that the diffusion enclosure comprises at least one longitudinal partition wall defining a main diffusion channel and at least one auxiliary diffusion channel of different lengths in the diffusion enclosure so as to create an offset in sound transmission at the output opening.

Thanks to the partition wall, several channels of sound diffusion are thus defined. Thus, sound can reach the exit opening via different paths.

The association of several channels allows, in the manner of an ear having a flag and a conch forming natural channels, a small time shift of the sound wave when it has circulated in said separate channels.

Preferably, the channels have different sections so as to modify the compression / decompression of the sound in a different manner depending on the channel in which it circulates. The processing of sound in a broadcast channel thus generates a time difference and compression which are a function of the structure of said channel.

The difference in length, shape and cross-section between the broadcast channels naturally increases spatiality by the offset of the sound waves which is interpreted by the ear as spatiality. The small sound offsets do not allow the sound to be modified, but allow its interpretation by the ear and the brain to be modified. This interpretation of sound by the brain is used in the present invention. Listening is remarkably pleasant and perfectly natural during the tests. Such immersion is all the more pleasant as it is carried out mechanically. The invention goes against current inventions which aim to increase the number and complexity of electronic components in headphones.

Furthermore, since the source of the sound emission is far from the outlet opening, the risk of hearing impairment is eliminated.

Preferably, the longitudinal partition wall is located in an upstream part of the diffusion enclosure. Thus, the sound is processed independently as soon as it enters the transmission device before being mixed to be transmitted to the user via the outlet opening. In other words, the sound is split due to the possibility of movement offered to it by the invention.

Preferably, the upstream part has a decreasing cross section from upstream to downstream. Thus, the sounds can be advantageously compressed during their transmission, which improves the dynamics and the intensity of said sounds. Thus, the sound wave circulates in a narrowed cross section channel, which improves the precision of the perceived sound, in a similar way to the vision of an eye observing a landscape through a small orifice.

Preferably, the main broadcast channel is shorter than the auxiliary broadcast channel. So the distance that sounds have to travel is different. In the position of use, the auxiliary diffusion channel can extend externally to the main diffusion channel with respect to the ear orifice. These traffic paths are different without increasing the size of the transmission device.

In one aspect, the auxiliary broadcast channel is removable from the main broadcast channel. Advantageously, one can have a plurality of auxiliary broadcasting channels of different properties which can be connected according to the needs and desires of the user to the main broadcasting channel. The transmission device is thus scalable and configurable. The collection advantageously includes auxiliary diffusion channels of different lengths and sections in order to process the sound in a different way.

Preferably, the auxiliary diffusion channel cooperates mechanically with the main diffusion channel, in particular, by interlocking by complementary shapes.

Preferably, the average cross section of the main diffusion channel is greater than that of the auxiliary diffusion channel. Thus, the compression of the sounds is different, which amplifies the phenomenon of spatiality. Preferably, the auxiliary diffusion channel has a decreasing cross section from upstream to downstream.

Preferably, the longitudinal partition wall has a length of between 40 mm and 75 mm. Such a separation length increases spatiality without disturbing the interpretation of sounds by the brain.

Preferably, said diffusion enclosure comprises, opposite said entry opening, a first vibration wall extending orthogonally to the entry axis capable of resonating following a sound emission along said entry axis.

Preferably, the main diffusion channel comprises at least one core in contact with the first vibration wall to tension it. The core increases the tension of the first vibration wall so that it vibrates in the manner of a drum skin. In addition, it increases the power of the sounds and thus avoids using an oversized source of sound emission.

Preferably, the diffusion enclosure comprising a second vibration wall parallel to the first vibration wall, said core is mounted between the first vibration wall and the second vibration wall to mechanically transmit the vibrations between said vibration walls. Thus, the vibrations of the two vibration walls are synchronized, which can help increase the spatiality of the sound.

Preferably, said upper core extends substantially parallel to said entry axis. Thus, said upper core has a limited size in the diffusion enclosure, which limits the risk of attenuation of the power of sounds.

According to a preferred aspect, said diffusion enclosure extending longitudinally, the diffusion enclosure comprises at least one harmony piece mounted in a lateral edge of said diffusion enclosure and projecting into the cavity of said enclosure broadcast. The harmony piece allows, like a harmony bar of a violin, to synthesize the sounds in order to balance the different sounds from the vibrations so as to form a coherent whole. Advantageously, the harmony piece at least partially fulfills a barrier function in the circulation of sound so as to tint the color thereof, in particular, by improving, as appropriate, the visibility of the treble, mids, and bass.

Preferably, the device comprises a lower chamber, in the sense of the position on the ear, which is blind. Such a blind chamber makes it possible to lengthen the path of circulation of sounds between the inlet opening and the outlet opening, which improves the spatiality as well as the dynamics by creating another time difference. The lower chamber leads to the outlet opening and thus forms another sound distribution channel. The lower blind chamber allows you to act synergistically with the different broadcasting channels by increasing the transmission of sound in an ear-like fashion. The lower chamber allows, in a synergistic way with the broadcasting channels, to temporally offset the sounds by allowing a displacement towards the back, in particular, for the low frequency sounds.

In one aspect, said blind lower chamber extends in line with the diffusion enclosure. Thus, the communication between the lower chamber and the diffusion enclosure is direct. The lower chamber and the diffusion enclosure extend opposite to the entrance opening.

More preferably, the first vibration wall forms part of the diffusion enclosure and of the lower chamber. Still preferably, the second vibration wall forms part of the diffusion enclosure and of the lower chamber.

The invention also relates to a headset comprising a sound transmission device as presented above and a sound emission source mounted in the inlet opening of said sound transmission device.

The invention further relates to a pair of headphones whose transmission devices are of different lengths. Preferably, the length of the transmission devices is adjustable in order to adapt to the morphology of each user, which provides additional comfort both for listening and for ergonomics when the transmission device is directly suspended from a ear of a user.

The invention relates both to a pair of earphones and to a headset comprising two earphones connected by a headband.

PRESENTATION OF THE FIGURES

The invention will be better understood on reading the description which follows, given solely by way of example, and referring to the appended drawings in which:

Figure 1 is a schematic representation of a sound transmission device according to the prior art in the position of use;

Figure 2 is a schematic representation of a sound transmission device according to the invention, of the earhook type, in the position of use;

Figure 3 is a schematic sectional view of the transmission device of Figure 2; and

Ια Figure 4 is a schematic representation of the correspondence of the structure of a transmission device according to the invention and the structure of a human ear.

It should be noted that the figures show the invention in detail to implement the invention, said figures can of course be used to better define the invention if necessary.

DESCRIPTION OF ONE OR MORE MODES OF IMPLEMENTATION AND IMPLEMENTATION

Referring to Figure 2, there is shown schematically an in-ear earphone 2 according to the invention.

The in-ear earpiece 2 includes a sound transmission device 4 in which a sound emission source 3 is mounted as illustrated in FIG. 3. In this exemplary embodiment, the sound emission source 3 is presented under the in the form of a loudspeaker, of diameter between 12 and 15 mm, connected to a portable audio player, a telephone or the like. However, it goes without saying that a wireless link, especially Bluetooth, may be suitable.

As illustrated in FIGS. 2 and 3, the sound transmission device 4 has an entry opening 41, extending along an entry axis X, which is capable of receiving the source of sound emission 3, in particular, a speaker. Also, preferably, the inlet opening 41 has an annular shape so as to cooperate by complementarity of shapes with a speaker of annular shape. The sound transmission device 4 further comprises an outlet opening 42 capable of being inserted into the conch at the entrance to the ear canal. For this purpose, the outlet opening 42 has a diameter of the order of 3 to 5 mm.

The sound transmission device 4 comprises a diffusion enclosure 40 able to conduct the sound from upstream to downstream from said inlet opening 41 to said outlet opening 42. In this embodiment, the sound transmission device 4 comprises a lower blind chamber 8 which extends from the inlet opening 41. By blind chamber 8 is meant a chamber devoid of opening with the exception of the inlet opening 41. As will be presented by thereafter, the blind lower chamber 8 makes it possible to reflect the sounds coming from the inlet opening 41 before returning them to the outlet opening 42.

Preferably, the sound transmission device has only a single inlet opening 41 and a single outlet opening 42 in order to avoid any reduction in the power of the sound between the inlet opening 41 and the outlet opening 42. Preferably, the inlet opening 41 includes a damper (glue, elastomeric seal, etc.) to dampen the vibrations generated by the sound emission source 3.

As illustrated in Figures 2 to 3, the sound transmission device 4 is curved so as to allow its ergonomic suspension on one ear 1. It goes without saying that the shape of the transmission device would be different for use in headphones.

As will be presented below, the diffusion enclosure 40 allows direct transmission of sound from the inlet opening 41 to the outlet opening 42 and mechanical processing of the sound by vibration.

In this embodiment, with reference to FIG. 2, the diffusion enclosure 40 successively comprises an upstream part 40A, an intermediate part 40B and a downstream part 40C for conducting sound between the inlet opening 41 and the outlet opening 42. In this example, the parts 40A-40C are connected together by interlocking but it goes without saying that certain parts could form a monobloc assembly, in particular, the upstream parts 40A and intermediate 40B so that the part downstream 40C remains orientable by the listener in order to facilitate the fitting of the earpiece 2 on his ear.

The parts 40A-40C of the diffusion enclosure 40 will now be presented independently.

The upstream part 40A advantageously makes it possible to generate a resonance in the diffusion enclosure 40 in order to mechanically shift the sound frequencies to create a spatiality of the sound.

Preferably, a portion of the upstream part 40A extends in a plane orthogonal to the entry axis X at the level of the entry opening 41. For this purpose, with reference to FIG. 3, the part upstream 40A comprises a first vibration wall opposite the inlet opening 41 and which extends orthogonally to the inlet axis X. Likewise, the upstream portion 40A comprises a second vibration wall 52 which is substantially parallel to the first vibration wall 51. As illustrated in FIG. 3, the inlet opening 41 is formed in the second vibration wall 52 so that the sound waves coming from the source of sound emission enter contact with the first vibration wall 51 so as to be then guided from upstream to downstream between the vibration walls 51, 52. The vibration walls 51, 52 are connected laterally by an interior side wall 53 and an exterior side wall 54. vibra walls tion 51, can be curved while remaining parallel to each other to match the shape of the listener's skull without altering the optimal quality of vibration that may exist. It goes without saying that the upstream part 40A could also not vibrate and form a resonator.

With reference to FIG. 2, the upstream part 40A of the diffusion enclosure 40 has a decreasing cross section from upstream to downstream so as to allow compression of the sound. Preferably, the upstream part 40A is curved at its downstream end so as to allow its ergonomic cooperation with an ear.

Preferably, the upstream part 40A is formed from a rigid material of the PVC type in order to allow optimal vibration of the vibration walls 51, 52 but it goes without saying that other materials could also be suitable.

Preferably, the upstream part 40A has a length between 3 and 5 cm and an upstream width between 10 and 15 mm and a downstream width between 3 and 5 mm. Advantageously, the upstream width is adapted to the width of the source of sound emission, that is to say, of the loudspeaker. It goes without saying that other dimensions could also be suitable.

More preferably, the thickness of the upstream part 40A is of the order of 1-3 mm so that a source of sound emission can vibrate the first vibration wall optimally.

According to the invention, amontα upstream part 40A of the diffusion enclosure 40 comprises a longitudinal partition wall 9 defining a main diffusion channel 6 and an auxiliary diffusion channel 7 of different lengths in the diffusion enclosure 40 which has the effect of increasing the spatiality of the sound broadcast.

In this example, the average cross section of the main diffusion channel 6 is greater than that of the auxiliary diffusion channel 7. The main diffusion channel 6 forms the shortest path between the inlet opening 41 and the opening 42. In other words, the main broadcast channel 6 is shorter than the auxiliary broadcast channel 7. The auxiliary broadcast channel 7 forms a bypass channel making it possible to offset the sound waves relative to the main broadcast channel 6 in order to to increase the psycho-acoustic impression of spatiality. The difference in time arrival at the ear of these waves is a few milliseconds due to the very small difference in length of the broadcasting channels 6, 7. The delay of the sound waves of sound is much less than 30 milliseconds beyond from which the ear perceives two different sounds (echo phenomenon).

Referring to Figure 2, the longitudinal partition wall 9 has a length between 40 mm and 75 mm and extends directly from the inlet opening 41. The thickness of the partition wall 9 is of the order of 1 mm.

A first end 7A of the auxiliary diffusion channel 7 opens directly into the inlet opening 41 while a second end 7B opens directly into the main diffusion channel 6 so as to allow a reunion of the sound which has known different circulation prior to its exit via the exit opening 42.

According to one aspect of the invention, the auxiliary diffusion channel 7 is removable from the main diffusion channel 6.

Advantageously, one can have a plurality of auxiliary broadcasting channels 6 of different properties which can be connected according to the needs and desires of the user to the main broadcasting channel. The transmission device 4 is thus scalable and configurable. The collection advantageously includes auxiliary diffusion channels 7 of different lengths and sections.

Preferably, the auxiliary diffusion channel 7 cooperates mechanically with the main diffusion channel 6, in particular, by interlocking by complementary shapes.

The intermediate part 40B advantageously makes it possible to guide the compressed sound between the upstream part 40A and the downstream part 40C. Referring to Figure 2, the intermediate part 40B of the diffusion enclosure 40 has a substantially constant cross section from upstream to downstream and is curved.

The downstream part 40C advantageously makes it possible to guide the compressed sound from the intermediate part 40B towards the outlet 42. To this end, the downstream part 40C is bent so as to facilitate its presentation in the conch of the ear 1 after its passage around the ear pavilion. Referring to Figure 2, the downstream part 40C of the diffusion enclosure 40 has a substantially constant cross section from upstream to downstream.

Optionally, the downstream end of the downstream part 40C can be provided with a tip in order to improve the interaction between the sound transmission device 4 and the listener's ear.

Besides the diffusion enclosure 40, the sound transmission device 4 comprises, in this example, a blind lower chamber 8 which extends in the extension of the upstream part 40A of the diffusion enclosure 40 as illustrated in FIGS. 2 and 3. In other words, the blind lower chamber 8 is diametrically opposite the diffusion enclosure 40 with respect to the inlet opening axis 41 as illustrated in FIG. 2. Preferably, the diffusion enclosure 40 and the lower blind chamber 8 are made of the same material, in particular PVC.

The lower blind chamber 8 is preferably hollow, that is to say, provided with a cavity. Also, the lower blind chamber 8 makes it possible to receive the sound in its cavity before returning it to the diffusion enclosure 40 until the outlet opening 42. The guiding of the sound in the lower blind chamber 8 makes it possible to increase the spacing of the sound frequencies (treble, medium and bass) and thus reinforce the spatiality of the sound perceived by the user. Such a lower chamber 8 is thus particularly advantageous. Such a blind chamber 8 is known from patent application FR3020737A1 and will not be presented in more detail.

According to one aspect of the invention, the sound transmission device 4 comprises an upper core 11 housed in the main diffusion channel of the upstream part 40A. The upper core 11 is arranged to exert a mechanical tension between the vibration walls 51, 52 in order to improve their vibratory characteristics in the manner of a violin core. In other words, the upper core 11 makes it possible to mechanically connect the first vibration wall 51 with the second vibration wall 52 so that any vibration from the first vibration wall 51 is communicated to the second vibration wall 52. It can also be provided a lower core in the blind lower chamber 8. The structure and function of a core was presented in patent application FR3020737A1 and will not be presented in more detail.

According to one aspect of the invention not shown, the transmission device 4 comprises a harmony piece mounted in a lateral edge of the upstream part 40A of the diffusion enclosure 40 and extending in the cavity of the enclosure diffusion 40. Such a harmony piece is known from patent application FR3020737A1 and will not be presented in more detail.

The invention further relates to a pair of headphones whose transmission devices 4 are of different lengths. Preferably, the length of the transmission devices 4 is adjustable in order to adapt to the morphology of each user, which provides additional comfort both for listening and for ergonomics.

With a setting adapted to each listener's ear, listening is more comfortable and natural. In particular, there is an enrichment of the bass giving more depth to the sound and an increased presence in the midrange offering better intelligibility to the overall sound rendering. The time difference between the two ears increases the impression of spatiality.

Referring to Figure 4, a human ear has a tympanum, an external auditory canal (EAC) and a pinna. By analyzing the structure of an ear, during natural listening, it appears that the horn prepares some of the sounds before their introduction into the external auditory canal. The philosophy of the present invention is to present the functions of the structure of an ear by means of the transmission device in order to produce a natural sound, interpreted as such by the ear and the brain, when it has been emitted. through a speaker.

The structure of the transmission device is inspired by the structure of the pavilion of the ear which essentially comprises a lower conch E6 which substantially surrounds the external auditory canal, an upper conch E8 and a navicular dimple E7 as illustrated in FIG. 4.

In a known manner, the role of the pavilion is to collect certain frequencies of sound, which has a preponderant role for stereophony and allows a spatial interpretation of sound (localization of a sound in the space around us). The spatiality of sound is for example used in animals to orient themselves.

In an application of the sound transmission device 4 according to the invention, the main diffusion channel 6, the auxiliary diffusion channel 7 and the rear chamber 8 correspond respectively to the lower conch E6, to the navicular dimple E7 and to the conch upper E8 of an ear E as illustrated in FIG. 4. Thus, the processing of sound by the transmission device 4 is analogous to that of an ear E and makes it possible to offer a deepened spatiality mechanically, listening then being more natural and therefore more accessible.

By way of example, a user equips each of his ears with an earpiece 2 according to the invention as illustrated in FIG. 2.

The user activates his music player which emits sounds via his speaker 3 in the inlet opening 41. The sound is led directly to the outlet opening 42 by the first main broadcast channel 6 and the channel auxiliary diffusion 7 so as to be treated before being conveyed to the outlet opening 42.

Preferably, the sound of the loudspeaker 3 vibrates the first vibration wall 51 which extends orthogonally to the entry axis X opposite the entry opening 41. Thanks to the upper core 11 , the second vibration walls 52 also vibrate synchronously, which increases the offset between the frequencies 5 of the sounds coming from the speaker 3 and therefore the spatiality

Certain sounds return to the outlet opening 42 after having circulated in the blind lower chamber 8. In other words, the sound emitted from the same source can circulate via four different paths before reaching the outlet opening 42.

The sound waves perceived by the user are slightly offset from each other. This results in increased spatiality and a strong feeling of immersion when listening, in particular, when a sound transmission device is used for each ear.

Claims (10)

1. Sound transmission device (4) for earphone (2), comprising an inlet opening (41) extending along an inlet axis (X), said inlet opening (41) being capable of receiving a sound emission source (3), an outlet opening (42) able to be presented in an ear and a diffusion enclosure (40) able to conduct the sound from upstream to downstream from said inlet opening (41 ) towards said outlet opening (42), device characterized in that the diffusion enclosure (40) comprises at least one longitudinal partition wall (9) defining a main diffusion channel (6) and at least one auxiliary diffusion (7) of different lengths in the diffusion enclosure (40) so as to create an offset in the transmission of sound at the outlet opening (42). 2. Device according to claim 1, wherein the longitudinal partition wall (9) is located in an upstream part (40A) of the diffusion enclosure (40). 3. Device according to claim 2, wherein the upstream part (40A) has a decreasing cross section from upstream to downstream. 4. Device according to one of claims 2 to 3, wherein the upstream part (40A) has a curved shape adapted to be mounted on an upper part of an ear. 5. Device according to one of claims 1 to 4, in which the main diffusion channel (6) is shorter than the auxiliary diffusion channel (7). 6. Device according to one of claims 1 to 5, wherein the average cross section of the main diffusion channel (6) is greater than that of the auxiliary diffusion channel (7). 7. Device according to one of claims 1 to 6, wherein the longitudinal partition wall (9) has a length between 40 mm and 75 mm. 8. Device according to one of claims 1 to 7, comprising a blind lower chamber (8). 9. Device according to one of claims 1 to 8, in which the diffusion channel 5 auxiliary (7) is removable from the main diffusion channel (6). 10. Earphone comprising a sound transmission device (4) according to one of the preceding claims and a sound emission source (3) mounted in the inlet opening (41) of said sound transmission device (4) .