Electroacoustic transducer

Abstract

The present invention relates to an electroacoustic transducer comprising: - a coil configured to receive an electrical signal and generate a resulting magnetic field; - at least one magnetic device arranged outside the coil, such that the resulting magnetic field extends in a direction substantially perpendicular to a longitudinal axis of the coil and generates a mechanical force in the longitudinal direction; - a ferromagnetic vibration part positioned inside the coil and secured to the coil; the magnetic device and the vibration part being arranged relative to one another in such a way (i) as to be in contact so that the magnetic device polarizes the vibration part; and (ii) that the vibration part is able to move relative to the magnetic device in a direction parallel to the longitudinal axis under the effect of the generated mechanical force.

Description

[0001] ELECTROACOUSTIC TRANSDUCER

[0002] FIELD OF INVENTION

[0003] The invention relates to an electroacoustic transducer, in particular for transmitting sound to a user by bone conduction, a listening device comprising the electroacoustic transducer and a hearing aid comprising the electroacoustic transducer.

[0004] STATE OF THE ART

[0005] Deafness or hearing loss affects hundreds of millions of people worldwide. Most hearing aids capture ambient sounds, process them, and then reproduce the resulting signal as an acoustic signal in the user's ear canal.

[0006] This type of hearing aid, which uses air conduction, has several drawbacks. Firstly, the sound delivered to the ear canal is not always of good quality, especially in noisy environments, giving the user a sensation of "buzz." Secondly, the sound is delivered in the conventional way to the ear canal of a hearing system that is inherently impaired, thus limiting the effectiveness of this type of device. Furthermore, inserting a device into the ear canal generates invasive pressure on the eardrum, which is undesirable. Finally, depending on the condition, such as the absence of an ear canal, this type of device is ineffective.

[0007] In cases of severe hearing loss or deafness, individuals can be fitted with a cochlear implant. This device consists of an external and an internal component surgically implanted in the skull. The external component captures and transforms ambient sounds into electrical signals, which are then transmitted to the internal component. The internal component emits electrical impulses that are sent to the cochlea, which in turn stimulates the auditory nerve fibers.

[0008] However, the effectiveness of cochlear implants remains limited for conversation in noisy environments or for music perception. Furthermore, the implantation of these devices requires a highly invasive surgical procedure followed by training with professionals, making them inaccessible to everyone. Finally, cochlear implants are also ineffective for certain types of pathologies. Bone conduction, the method of transmitting sound, is therefore an interesting alternative to the aforementioned methods, as it allows sound to be transmitted non-surgically and without using the ear canal.

[0009] Numerous devices exist for transmitting sound to a person using bone conduction. These devices allow a user to receive an audio signal from an electrical device, such as a telephone or music player. They include an electroacoustic transducer that transmits vibrations corresponding to the sound signal via bone conduction. However, the sound reproduction from these devices via bone conduction is insufficient, making it necessary to supplement bone conduction transmission with air transmission through the ear canal. Furthermore, because the sound transmitted via bone conduction is of insufficient quality, it cannot be heard by deaf or hard-of-hearing individuals.

[0010] There is therefore a need to develop a non-invasive hearing solution that is simple to use and implement, and that allows people with hearing loss or deafness to hear surrounding sounds with optimized and natural quality, regardless of the location, ambient noise, and the user's condition.

[0011] DESCRIPTION OF THE INVENTION

[0012] The invention aims to enable deaf or hard-of-hearing people to hear a sound signal from an surrounding sound and / or from an electrical device such as a telephone or a music player.

[0013] The invention also aims to improve the quality of a sound signal transmitted to a user by bone conduction using an electroacoustic transducer and to eliminate the need to supplement the transmission by a method such as, for example, via the air.

[0014] The invention thus relates to an electroacoustic transducer comprising:

[0015] - a coil configured to receive an electrical signal and generate a resulting magnetic field, the coil having a longitudinal axis; at least one magnetic device disposed outside the coil so that the resulting magnetic field extends in a direction substantially perpendicular to the longitudinal axis and generates a mechanical force extending substantially along the longitudinal direction;

[0016] - a ferromagnetic vibrating element positioned inside the coil and attached to the coil; the magnetic device and the vibrating element being arranged relative to each other so as to

[0017] (i) be in contact so that the magnetic device polarizes the vibrating part; and that

[0018] (ii) the vibrating part is mobile relative to the magnetic device in a direction parallel to the longitudinal axis under the effect of the generated mechanical force.

[0019] This electroacoustic transducer ensures that the vibration element's movement accurately reflects the electrical signal received by the coil. The arrangement of the coil, magnetic device, and vibration element prevents friction between them, thus avoiding distortion of the electrical signal. Specifically, the vibration element's movement transmits acoustic vibrations to the surface it contacts, these vibrations representing the received electrical signal. Therefore, when the electroacoustic transducer is worn by a user, with the vibration element positioned against their skin, particularly on the bony area around their ear, the movement of the vibration element transmits vibrations representative of the electrical signal to the user via bone conduction.The electroacoustic transducer according to the invention enables reliable and representative reproduction of the electrical signal. When the electrical signal is generated from an audio signal, the user can thus hear the audio signal in an optimized manner via bone conduction, preferably exclusively via bone conduction.

[0020] When it is stated that the ferromagnetic vibrating element is fixed to the coil, this means that any movement of the vibrating element relative to the coil is prevented, particularly translational movements. In prior art electroacoustic transducers, the ferromagnetic vibrating element is generally mobile relative to the coil, which creates friction and leads to distortion in the conversion of the electrical signal into acoustic vibrations. The resulting acoustic vibrations are of low quality and do not reproduce the electrical signal optimally.

[0021] When an electroacoustic transducer is used to enable a user to hear a sound by means of the acoustic vibrations generated from that sound—the sound may come from an electrical device such as a mobile phone or MP3 player, or from sounds emitted in the user's environment—it is called a listening device. When an electroacoustic transducer is used to enable a deaf or hard-of-hearing user to hear a sound by means of the acoustic vibrations generated from that sound—the sound may come from an electrical device such as a mobile phone or MP3 player, or from sounds emitted in the user's environment—it is called a hearing aid.

[0022] The magnetic device may consist of a single magnet or multiple magnets.

[0023] The coil is a solenoid whose insulated metallic electrical wire, preferably copper, is wound helically around a longitudinal axis Y to form an internal cavity. Preferably, the radius R of the solenoid is greater than the length L measured along the direction of the longitudinal axis Y.

[0024] The coil resistance can range from 4 to 32 Q, and preferably from 4 to 16 Q when the electroacoustic transducer is used in a hearing aid.

[0025] The electrical signal passing through the coil can be a direct current or an alternating current.

[0026] According to specific embodiments that can be used alone or in combination:

[0027] - Contact between the magnetic device and the vibrating part is maintained during the movement of the vibrating part relative to the magnetic device; preferably, the magnetic device and the vibrating part are always in contact with each other; the contact between the magnetic device and the vibrating part is achieved by means of an elastic device; thus, the vibrating part can move relative to the magnetic device while maintaining contact between these two parts during the movement of the vibrating part; the contact between the elastic device and the vibrating part can be direct or via one or more other parts; the contact between the magnetic device and the vibrating part via the elastic device preferably allows the polarization of the ferromagnetic vibrating part by means of the magnetic device;the elastic device is preferably ferromagnetic; the elastic device may be an elastic portion of the magnetic device, an elastic portion of the vibrating part, and / or an additional part that is at least partially elastic;

[0028] - The elastic device has a thickness, with elasticity being achieved by means of at least one groove running through the elastic device in its thickness; thus, elasticity can be achieved simply and without using any additional parts; elasticity can be achieved by creating one or more grooves with a specific geometry of the desired degree of elasticity; the elastic device can be, for example, a strip; the elasticity of the elastic device along the longitudinal axis Y can, for example, be between 1000 N / mm and 100,000 N / mm; - The elastic device comprises a rigid portion that is in contact with the magnetic device and the vibrating part, and an elastic portion that is in contact with the vibrating part and is separated from the magnetic device by a gap;Thus, a single part allows for maintaining contact between the vibrating device and the magnetic device and for the mobility of the vibrating device relative to the magnetic device; the contact of the rigid portion with the vibrating part can be direct or achieved by means of one or more additional parts; the contact of the rigid portion with the magnetic device can be direct or achieved by means of one or more additional parts; the void space allows the elastic portion to move under the effect of the generated magnetic force, in particular in a direction parallel to the longitudinal axis Y, without the elastic portion rubbing against any part of the electroacoustic transducer; the height h of the void space along the longitudinal axis Y is preferably greater than the maximum amplitude of the displacement of the elastic portion;

[0029] - the elastic device comprises an annular piece including the rigid portion and the elastic portion; such an elastic device is preferably used when the electroacoustic transducer has axial symmetry of revolution around the longitudinal axis Y; the annular piece has an inner circle delimiting a central empty space; according to a preferred embodiment, the annular piece surrounds the vibrating piece;

[0030] - the elastic portion is positioned in an inner part of the annular piece; preferably, the elastic portion does not overlap the coil in a direction parallel to the longitudinal axis Y, meaning that there is no overlap between the elastic portion and the coil in this direction; according to a preferred embodiment, the inner circle of the annular piece has a diameter greater than the outer diameter of the coil so that during movements of the elastic portion along the longitudinal axis Y, the annular piece does not risk coming into contact with the coil; the magnetic device comprises a ring magnet surrounding the coil; such an elastic device is preferably used when the electroacoustic transducer has axial symmetry of revolution about the longitudinal axis Y;According to one possible embodiment, the magnetic device may comprise two magnets positioned diametrically opposite outside the coil;

[0031] - the vibrating part has a contact surface on which an adhesive strip is positioned to hold the electroacoustic transducer against the user's skin; thus, the transducer can be held on a specific area of ​​the user's skin, preferably on the skin over the bony area, allowing the user to hear sounds in an optimized way; and

[0032] - the electroacoustic transducer also includes an electronic board allowing the coil to be connected to an electrical circuit; the electronic board includes in particular the components necessary to receive an incoming electrical signal and transmit an outgoing electrical signal to the coil.

[0033] The invention also relates to a listening device comprising at least one electroacoustic transducer as previously described and a signal processing unit configured to transmit an electrical signal to the coil. The listening device is intended to be positioned around a user's ear by placing the vibrating element in contact with a bony area. The signal processing unit includes, in particular, an electronic circuit board for transmitting an electrical signal to the conductive wire forming the coil.

[0034] The electroacoustic transducer according to the invention allows for a reliable and representative reproduction of the electrical signal, the user hears the desired sound by bone conduction in a clear and optimized manner.

[0035] The electrical signal transmitted to the coil is an output signal; the processing unit is further configured to receive an input signal and process it to generate the output signal. The input signal is thus processed, for example, to remove background noise, amplify and / or attenuate certain frequency ranges.

[0036] The incoming signal originates from ambient sound and / or an auxiliary electrical device connected to the listening device. When the incoming signal originates from ambient sound, the listening device includes at least one microphone capable of capturing the ambient sound and converting it into an incoming electrical signal, which can then be converted into an outgoing electrical signal that is transmitted to the coil.

[0037] The invention further relates to a bone conduction hearing aid, particularly for a deaf or hard-of-hearing user, comprising a listening device as previously described, the electroacoustic transducer being a first electroacoustic transducer, the hearing aid further comprising a second electroacoustic transducer, the first electroacoustic transducer being configured to be positioned in contact with a first bony area of ​​the user's head and to transmit first vibrations to the first bony area, and the second electroacoustic transducer being configured to be positioned in contact with a second bony area of ​​the user's head and to transmit first vibrations to the second bony area.The aforementioned hearing aid stimulates the auditory nerve of the ear around which the device is positioned via bone conduction, using the first and second vibrations. These vibrations directly reach the same auditory nerve (that of the ear around which the device is positioned) through the bone, without any signal loss. A user wearing this hearing aid thus obtains improved sound reproduction compared to hearing aids or listening devices that use air conduction.

[0038] This hearing aid can be used by a person with good hearing or by a deaf or hard-of-hearing person.

[0039] Advantageously, the method allows for the stimulation of two different parts of the auditory nerve using two bone conduction devices positioned at precise points in the user's anatomy. Thus, the method allows the user to experience the entire auditory spectrum, unlike a device that would use only one bone conduction point.

[0040] In the present invention, when it is stated that a bone conduction device is positioned around the ear, this means that it is positioned in contact with bony parts located around said ear, preferably at a distance of no more than 3 cm from the nearest point on the periphery of the ear, and preferably at a distance of no more than 2 cm. However, for users with atypical morphology, the bone conduction device may be positioned at a greater distance from the ear, for example, at the level of the temple bone.

[0041] Furthermore, in the present invention, when it is stated that a device is in contact with a bony area, this means that the device is in direct or indirect contact with said bony area, at a precise point of contact. Indirect contact could, for example, be contact via the skin and the tissues located between the skin and the bony area.

[0042] The first and second electroacoustic transducers are positioned on the user's skin according to their individual anatomy, ensuring that vibrations reach the auditory nerve in an optimal manner. Advantageously, the first and second electroacoustic transducers are easily repositioned around the ear, allowing the hearing aid to be customized to each user's unique anatomy.

[0043] Advantageously, the first and second electroacoustic transducers transmit vibrations through bone, specifically through the bone between the area on which each transducer is positioned and the auditory nerve. Thus, the auditory nerve is stimulated even when various components of the auditory system, such as the eardrum or cochlea, are damaged. Furthermore, this transmission method avoids stressing already weakened parts of the auditory system and, for example, prevents sending a sound signal to a damaged eardrum.

[0044] The cochlea has several zones, including a central zone that receives acoustic vibrations of medium to very low frequencies (bass sounds) and a peripheral zone that receives acoustic vibrations of medium to very high frequencies (treble sounds). In other words, the lower the frequencies of the acoustic vibrations, the deeper they penetrate the cochlea.

[0045] Preferably, the bony area on which the electroacoustic transducer is positioned can be predefined to achieve optimal stimulation of the auditory nerve. This bony area can be defined based on the morphology of the user's ear and / or head bones, so that the electroacoustic transducer, positioned on the bony area, transmits acoustic vibrations to the desired portion of the auditory nerve. In this way, the hearing aid can be personalized to each user's specific needs, including the degree and cause of their hearing loss.

[0046] The bony area may be part of the user's skull and / or jaw.

[0047] When a hearing aid has multiple electroacoustic transducers positioned around the same ear, it is possible to stimulate different parts of the auditory nerve, thus selecting, refining, and expanding the range of frequencies received by the auditory nerve. This improves the quality of the sound heard by the user.

[0048] In particular, the auditory spectrum includes the following frequency ranges: very low frequencies (20 Hz to 40 Hz), low frequencies (40 Hz to 160 Hz), medium low frequencies (160 Hz to 315 Hz), medium frequencies (315 Hz to 2.5 kHz), medium high frequencies (2.5 kHz to 5 kHz), high frequencies (5 kHz to 10 kHz), and very high frequencies (10 kHz to 20 kHz). The electroacoustic transducer according to the invention can transmit the entire frequency range of the auditory spectrum to a user. Thus, a hearing aid incorporating this electroacoustic transducer can deliver the entire frequency range of the auditory spectrum to a deaf or hard-of-hearing user.

[0049] DESCRIPTION OF THE FIGURES

[0050] Other features and advantages of the invention will become apparent from the following description, given solely by way of example and with reference to the accompanying drawings, in which:

[0051] - [Fig. 1] represents a schematic cross-sectional view of an electroacoustic transducer according to one embodiment of the invention;

[0052] - [Fig. 2] represents a schematic top view of an annular strip usable in the electroacoustic transducer of figure 1;

[0053] - [Fig. 3] represents a schematic top perspective view of the electroacoustic transducer of figure 1;

[0054] - [Fig. 4a] and [Fig. 4b] represent a schematic cross-sectional view of the electroacoustic transducer of figure 1 in operation;

[0055] - [Fig. 5] represents a schematic top and perspective view of a listening device according to one embodiment of the invention;

[0056] - [Fig. 6] represents a schematic top view of a hearing aid according to an embodiment of the invention positioned around the ear of a user.

[0057] DETAILED DESCRIPTION OF THE INVENTION

[0058] For the sake of clarity, only the essential elements for understanding the invention have been represented schematically, and this without regard to scale.

[0059] In Figure 1, an electroacoustic transducer 10 includes a coil 20 configured to receive an electrical signal and generate a resulting magnetic field B. The coil 20 has a longitudinal axis Y.

[0060] The electroacoustic transducer 10 further includes a magnetic device 30 disposed outside the coil 20 so that the resulting magnetic field B extends in a direction substantially perpendicular to the longitudinal axis Y and generates a mechanical force F extending substantially in a direction parallel to the longitudinal axis Y.

[0061] The electroacoustic transducer 10 also includes a ferromagnetic vibration piece 40 positioned inside the coil 20. The vibration piece 40 is fixed to the coil 20, which means that any movement of the vibration piece 40 relative to the coil 20 is prevented, in particular translational movements in a direction parallel to the longitudinal axis Y.

[0062] The magnetic device 30 and the vibrating part 40 are arranged relative to each other so that, on the one hand, these two parts are in contact so that the magnetic device 30 polarizes the vibrating part 40, and, on the other hand, the vibrating part 40 is mobile relative to the magnetic device 30 in a direction parallel to the longitudinal axis Y under the effect of the generated mechanical force F.

[0063] The electroacoustic transducer 10 thus allows the transmission of vibrations V by the vibrating part 40 which are representative of the electrical signal received and circulating in the coil 20. Indeed, the arrangement of the coil 20, the magnetic device 30 and the vibrating part 40 relative to each other makes it possible to avoid friction between them and therefore distortion of the signal during the transformation of the electrical signal received by the coil 20 into mechanical force F and then into electroacoustic vibrations V by the mobility of the vibrating part 40.

[0064] Thus, when the electroacoustic transducer 10 is worn by a user, with the vibrating element 40, and in particular its outer surface 42, positioned in contact with the user's skin, especially on a bony area around their ear, the mobility of the vibrating element 40 allows the transmission to the user of vibrations V representative of the electrical signal via bone conduction. The reproduction of the electrical signal as electroacoustic vibrations is then reliable and representative. When the electrical signal is generated from an audio signal, the user can thus hear the audio signal in an optimized manner via bone conduction, preferably exclusively via bone conduction.

[0065] According to this embodiment, the electroacoustic transducer 10 has axial symmetry of revolution about the Y axis and the various parts forming the electroacoustic transducer 10 have axial symmetry of revolution about the Y axis. However, according to another possible embodiment, certain parts or devices, such as for example the magnetic device 30, may comprise two elements positioned diametrically opposite with respect to the Y axis.

[0066] The coil 20 is a solenoid whose electrical wire is made of insulated copper and wound in a helix around the longitudinal axis Y. The helix classically forms an internal cavity 22.

[0067] In this embodiment, the length L1 of the coil 20 is between 2 and 5 millimeters (mm) and its radius R is between 3 and 7 mm when the electroacoustic transducer is used in a hearing aid. Furthermore, the resistance of the coil can range from 4 to 32 Ω, and preferably from 4 to 16 Ω, when the electroacoustic transducer is used in a hearing aid.

[0068] When an electrical signal passes through the coil, generating the resulting magnetic field B and mechanical force F, the coil 20 moves in translation along a direction parallel to the longitudinal axis Y. The coil 20 moves simultaneously with the vibrating element 40, since these two elements are fixed to each other. Thus, no friction occurs at the interface between these two elements, preventing any distortion of the signal when it is transformed into vibrations V.

[0069] The coil 20 comprises an inner surface 24 delimiting the inner cavity 22 and an outer surface 26, the inner surface 24 and the outer surface 26 being separated from each other by the helix 25 formed by the electrical wires. Furthermore, the coil 20 is delimited lengthwise by a first surface 27 and a second surface 28, the first and second surfaces 27 and 28 extending along an axis substantially perpendicular to the longitudinal axis Y.

[0070] The inner surface 24 and the second surface 28 are in contact with the vibrating part 40. In contrast, the outer surface 26 and the first surface 27 are surrounded by a void 29. Thus, the only part with which the coil 20 is in contact is the vibrating part 40, to which it is fixed. The coil 20 therefore experiences no friction with any part of the electroacoustic transducer 10.

[0071] Vibrating part

[0072] The vibrating part 40 is a one-piece part made of ferromagnetic material which, in this embodiment of low-carbon steel, contains at most 0.2% carbon.

[0073] The vibrating part 40 is cylindrical and comprises a central body 44 surmounted by a transmission part 46.

[0074] The cylindrical body 44 has a first diameter D1 and is positioned in the inner cavity 22 of the coil 20 so as to be in direct contact with the inner surface 24 of the coil 20. In this embodiment, the cylindrical body 44 has a length L2 that is greater than the length L1 of the coil. Thus, the cylindrical body 44 extends along the entire length of the coil 20 and also into a portion of the empty space 29. However, according to other possible embodiments, the central body 44 may extend only over a portion of the length L1 of the coil.

[0075] The transmission part 46 has a second diameter D2 greater than the diameter D1 so as to be in contact with the second surface 28 of the coil 20. In this embodiment, the transmission part 46 extends over the entire second surface 28. However, according to possible alternative embodiments, the transmission part may extend only over a part of the second surface 28 or even have a diameter equal to the diameter of the central body.

[0076] The transmission portion 46 includes a contact surface 42 intended to be placed on the skin of a user, in particular on the skin of a bony area around a user's ear. According to this embodiment, the contact surface 42 is covered with an adhesive membrane 49 so that the electroacoustic transducer can remain attached to the user's skin, preferably without requiring a retaining device such as a headband around the user's ear or head. The adhesive membrane 49 is, for example, a double-sided adhesive membrane.

[0077] Magnetic device

[0078] The magnetic device 30 is a ring magnet that surrounds the coil 20. In this embodiment, the ring magnet is made of a material comprising neodymium, and preferably is made of neodymium.

[0079] The ring magnet 30 has a width 11 allowing it to be at a distance from the coil 20. Thus, the ring magnet 30 is not in contact with the coil 20 and is spaced from the coil 20 by the empty space 29.

[0080] The ring magnet 30 is positioned around the coil such that the magnetic field B extends in a direction perpendicular to the longitudinal axis Y. In particular, the ring magnet 30 and the coil 20 are at least partially aligned in a radial direction. That is, at least a portion of the ring magnet 30 is positioned between the first surface 27 and the second surface 28. Preferably, at least 30% of a height H of the ring magnet 30 is positioned between the first surface 27 and the second surface 28. Furthermore, a median plane P1 of the ring magnet 30 is positioned between the first surface 27 and the second surface 28, the median plane P1 being a plane of symmetry of the ring magnet extending in a direction perpendicular to the longitudinal axis Y.Preferably, the median plane P1 of the ring magnet is positioned at the same level as a median plane P2 of the coil 20 or between the median plane P2 of the coil 20 and the first surface 27 of the coil 20.

[0081] The ring magnet 30 is in contact with the vibrating part 40, such that the magnet polarizes the ferromagnetic vibrating part 40. The contact between the ring magnet 30 and the vibrating part 40 can be direct or indirect. Whether direct or indirect, the contact allows the vibrating part 40 to move relative to the ring magnet 30 in a direction parallel to the longitudinal axis. Thus, the Laplace force generated by the magnetic field B can move the vibrating part 40 in response to the electric field. The vibrating part 40 can then transmit vibrations to a bony area of ​​the user against which the vibrating part 40 is positioned.

[0082] In this embodiment, contact between the ring magnet 30 and the vibrating part 40 is achieved via two additional parts made of ferromagnetic material, one of which is an elastic device. Thus, contact between the ring magnet 30 and the vibrating part 40 is maintained during the movement of the vibrating part 40 relative to the ring magnet.

[0083] In another possible embodiment, the contact between the ring magnet and the vibrating part can be direct. According to this embodiment, the ring magnet and / or the vibrating part includes an elastic portion at which the contact is made, allowing the vibrating part to move relative to the ring magnet without breaking contact.

[0084] In this embodiment, the elastic device is an annular strip 50 allowing contact between the vibrating part 40 and the annular magnet 30. The annular strip 50 is made of ferromagnetic material so as to transmit the magnetization to the vibrating part 40.

[0085] The annular lamella 50 has a thickness E in which grooves 52a-c are formed. These grooves extend through the entire thickness of the annular lamella 50, thus forming through grooves. As shown in Figure 2, the grooves 52a, 52b, and 52c have a specific shape to achieve the desired elasticity. The grooves can, for example, be created by laser cutting. It is therefore possible to obtain an elastic portion 54 in the annular lamella 50 simply and without using any additional parts.

[0086] According to other embodiment variants, the annular lamella 50 may have more or fewer grooves and / or grooves of different geometry.

[0087] The thickness E of the annular lamella 50 also allows for specific membrane elasticity, enabling the achievement of the desired resonance peak. This makes it possible to favor the desired frequencies depending on the application of the electroacoustic transducer.

[0088] The annular lamella 50 thus has an elastic portion 54 containing grooves. It also has a rigid portion 56 which has no grooves. The elastic portion 54 is positioned in an inner part of the annular lamella 50 and the rigid portion is positioned in an outer part of the annular lamella 50.

[0089] The annular slat 50 has an inner circle Ci and an outer circle Ce. In this embodiment, the inner circle Ci has a radius greater than the radius R of the coil 20. However, according to a possible alternative embodiment, the inner circle Ci may have a radius less than the radius R of the coil 20 and therefore be partially positioned between the coil 20 and the vibrating part 40.

[0090] The rigid portion is in contact with the ring magnet 30 via a first ferromagnetic add-on piece 57. This first add-on piece 57 is annular, with the width 12 of its ring being smaller than the width 11 of the ring magnet 30. Thus, the first add-on piece 57 is in direct contact with the ring magnet 30 and with the rigid portion 56 of the annular strip 50, but the elastic portion 54 is at a distance from the ring magnet 30.

[0091] The elastic portion 54 is positioned in an annular groove 48 of the vibrating part 40. Thus, the elastic portion 54 is partially positioned under the transmission part 46 and can therefore lift the vibrating part 40 under the effect of the force F. The elastic portion 54, the vibrating part 40, and the coil 20 are press-fitted together so that they are rigidly joined without the need for fastening means. The elastic portion 54 is therefore in direct contact with the vibrating part 40 but separated from the annular magnet 30 by the gap 29. Thus, when the Laplace force is generated, the elastic portion 54 can move towards and away from the annular magnet 30 without contacting it, carrying the vibrating part 40 and the coil 20 with it.The annular strip 50 therefore allows, on the one hand, to maintain contact between the annular magnet 30 and the vibrating part 40 and to transfer the magnetism, and, on the other hand, to allow the vibrating part 40 to be mobile relative to the annular magnet 30 under the effect of the Laplace force.

[0092] The annular lamella 50 thus combines the elastic function and magnetic conduction, allows controlled rigidity in a small space, while minimizing sound distortion and allowing the vibration to be conducted directly to the skin via the vibration piece 40.

[0093] Electroacoustic transducer

[0094] The electroacoustic transducer further comprises a second ferromagnetic component 58. The first and second components 57 and 58 allow the magnetic field to be concentrated in the desired direction, thus improving the efficiency of the linear displacement of the vibrating component 40 and the coil 30.

[0095] Furthermore, the transducer includes a housing 60 in which the annular strip 50, the annular magnet 30, and the first and second additional parts 57 and 58 are positioned. In this embodiment, the various parts are press-fitted into the housing. According to other possible embodiments, they can be attached to the housing by gluing, by means of screws, or by any other means.

[0096] The electroacoustic transducer also includes an electronic board 70 to which the incoming and outgoing electrical wire is connected, so that it can receive an incoming electrical signal and circulate it in the coil.

[0097] The housing 60 has two openings 62 allowing the passage of the electrical wire entering and exiting the coil 20.

[0098] Operation of the electroacoustic transducer

[0099] As shown in Figures 4a and 4b, the Laplace force can either move the vibrating part 40 away from the ring magnet 30, or move the vibrating part 40 towards the ring magnet 30. In particular, in this embodiment, the electrical signal received by the coil 20 corresponds to an audio signal to be transmitted to a user equipped with the electroacoustic transducer 10. The electrical signal is an alternating current which, when it passes through the coil 20, conventionally causes the appearance of a magnetic field B. The magnetic field B is oriented alternately in a first direction (Figure 4a) and in a second direction (Figure 4b) opposite to the first direction, the first and second directions being substantially perpendicular to the longitudinal axis Y due to the position of the ring magnet 30 around the coil 20.

[0100] As shown in Figure 4a, when the magnetic field B is oriented along the first direction, the resulting Laplace force F exerts a thrust on the vibrating part 40 which moves in a direction parallel to the longitudinal axis away from the ring magnet 30.

[0101] As shown in Figure 4b, when the magnetic field B is oriented along the second direction, the resulting Laplace force F exerts an attraction on the vibrating part 40 which moves in a direction parallel to the longitudinal axis as it approaches the ring magnet 30.

[0102] These movements of the vibrating part 40 thus enable the transmission of electroacoustic vibrations to the user's bony area with which it is in contact, particularly to the skin covering this bony area. The electroacoustic vibrations correspond to the electrical signal passing through the coil. The vibrating part can be in contact with the bony area directly or via an additional component, such as a metal plate. The electroacoustic transducer is configured so that the electroacoustic vibrations correspond with optimized reliability to the electrical signal passing through the coil 20. In particular:

[0103] - the position of the ring magnet 30 around the coil 20 allows the magnetic field and the resulting Laplace force to have the desired orientation;

[0104] - the fact that the coil 20 is fixed to the vibration part 40 avoids any friction between these two parts;

[0105] - the empty space 29 prevents the coil 20 and the vibration part 40 from coming into contact with other parts of the transducer 10 during their movement;

[0106] - the annular lamella 50 has the elasticity adapted to the electroacoustic vibrations to be transmitted; and

[0107] - the empty space 29 is dimensioned so that the annular slat 50 does not risk coming into contact with the annular magnet 50 even when the displacement is at its maximum amplitude.

[0108] In this embodiment, the various parts forming the electroacoustic transducer are concentric. However, according to another possible embodiment, the parts other than the coil 20 might not be annular or circular. For example, the vibrating part might be elongated, for example substantially rectangular, and the magnetic device, the additional ferromagnetic parts, and the elastic device could each comprise two parts arranged diametrically opposite each other with respect to the coil 20, along the longitudinal axis of the vibrating part. According to such an embodiment, the elastic device would comprise two elastic portions that together set the vibrating part in motion.

[0109] Listening device

[0110] The invention also relates to a listening device 80 comprising the electroacoustic transducer 10 and a processing unit 82. The transducer 10 is connected to the processing unit 82 via a transmission cable 84. However, the processing unit can also be connected to the electroacoustic transducer 10 by a wireless connection.

[0111] The listening device 80 allows a user to listen to a sound coming from an electrical signal, the electrical signal being able to come from an electrical device such as a telephone, a music player, a television, a computer, a video game console or any other device emitting an electrical signal from a sound.

[0112] The electrical signal transmitted to the coil is an output signal; the processing unit is further configured to receive an input signal and process it to generate the output signal. The input signal is thus processed to, for example, remove background noise, amplify and / or attenuate certain frequency ranges.

[0113] The incoming signal originates from ambient sound (acoustic waves) and / or an auxiliary electrical device connected to the listening device. The processing unit includes, in particular, a device for receiving an electrical signal representing sound. If the sound originates from an electrical device, the receiving device receives the electrical signal directly. When the incoming signal originates from ambient sound, the listening device includes at least one microphone capable of capturing the ambient sound, which consists of acoustic waves, and converting it into an incoming electrical signal. This signal can then be converted by the processing unit into an outgoing electrical signal, which is transmitted to the coil.

[0114] The microphone can be any type of microphone and preferably a MEMS (Micro Electro Mechanical System) type microphone.

[0115] Preferably, the microphone can capture frequency ranges from at least 60 Hz to 20 kHz, which corresponds to the frequency ranges of the auditory spectrum, and can also capture frequency ranges beyond this range.

[0116] Furthermore, the microphone's dynamic range can go from 50 dB to 100 dB without showing any saturation.

[0117] The processing unit transforms the input signal into an output signal in a short time, ideally less than 6 milliseconds. The input signal comes from ambient sound and / or an auxiliary electrical device. The processing unit includes a series of filters, which can be described as quadratic, gain, multi-band, equalizer, and / or compressor. These various filters modulate the input electrical signal as needed to produce a modified output signal, thus ensuring the sound can be adapted for a person with normal hearing or one with specific hearing loss.

[0118] The processing unit allows, among other things, the modulation of received electrical signals, as well as the addition of audio tracks, thus enabling the listening of ambient sound coupled with an audio track from an external electrical device. A hearing-impaired person can therefore listen to a sound source such as the television while continuing to hear surrounding sounds, or listen to music from an electrical device while hearing ambient sounds, by modulating each signal to ensure optimal listening comfort.

[0119] It is also possible to apply an artificial intelligence (AI) algorithm to the signal during its processing. The processing unit then includes an intelligent AI program and a chip with an architecture that enables this type of processing. The algorithm or program allows for the addition of selective filtering, enabling, for example, a hearing-impaired person to hear a sound that prioritizes the voice of a third party speaking to them while minimizing background or ambient noise. The program can be fixed in its learning state during its first use or continue to learn, adapting to the lifestyle and needs of the hearing-impaired person.

[0120] When the acoustic device allows surrounding sounds to be heard, it includes one or more microphones that can be oriented differently and that are connected by wire or wirelessly to the processing unit 82. In this case, the algorithm will use as inputs the electrical signals from each of the microphones.

[0121] When the acoustic device allows sound to be heard from electrical devices, the processing unit includes a wired or wireless interface with these electrical devices.

[0122] To enable the calculations necessary for signal processing, at least one chip containing the filters and sized according to the needs and speed of the calculations may be present. This chip is accompanied by a quartz crystal or other electronic element enabling timing, a battery management unit, and a battery or non-rechargeable power source. The chip may contain or be accompanied by an analog-to-digital converter unit and a digital-to-analog converter unit, RAM and hard memory, and a module allowing remote configuration or configuration via cable connection. The embedded software performs the signal processing.

[0123] Hearing aid

[0124] As shown in Figure 6, the invention also relates to a hearing aid 90 intended to be worn by deaf or hard-of-hearing users but also by users without hearing problems.

[0125] The hearing aid 90 includes the electroacoustic transducer 10, a second electroacoustic transducer 10', and also the processing unit 82 as previously described.

[0126] In this embodiment, the first electroacoustic transducer 10 is positioned behind the ear 5, in contact with the mastoid process of the temporal bone, and the second electroacoustic transducer 10' is positioned in front of the ear 5, in contact with the temporal bone, near the temporomandibular joint. However, depending on the user's anatomy, the first and / or second devices may be positioned in contact with another bone, for example, the temple, so as to ensure optimized stimulation of the auditory nerve.

[0127] The first electroacoustic transducer 10 generates and transmits the first vibrations 2 and the second electroacoustic transducer 10' generates and transmits the first vibrations 3. The first and second electroacoustic transducers 10 and 10' being positioned around the same ear 5, the first and second vibrations 2 and 3 stimulate the same auditory nerve 6, namely the auditory nerve of ear 5, which allows the user to perceive improved sound compared to prior art hearing aids.

[0128] In this embodiment, the first bone conduction device 2 is positioned in contact with the mastoid process of the temporal bone, and the second bone conduction device 3 is positioned in contact with the temporal bone. The user thus receives a complete reproduction of ambient sound, since all wavelengths of the auditory spectrum reach the auditory nerve.

[0129] When the hearing aid allows the user to hear surrounding sounds, it includes one or more microphones that can be oriented differently and that are connected by wire or wirelessly to the processing unit 82.

[0130] When the hearing aid allows the hearing of a sound coming from electrical devices, the processing unit includes a wired or wireless interface with these electrical devices.

Claims

DEMANDS 1. Electroacoustic transducer (10) comprising: a coil (20) configured to receive an electrical signal and generate a resulting magnetic field (B), the coil (20) having a longitudinal axis (Y); - at least one magnetic device (30) disposed outside the coil (20) so that the resulting magnetic field (B) extends in a direction substantially perpendicular to the longitudinal axis and generates a mechanical force (F) extending substantially along the longitudinal direction (Y); - a ferromagnetic vibrating part (40) positioned inside the coil (20) and attached to the coil (20); the magnetic device (30) and the vibrating part (40) being arranged relative to each other so as to (i) be in contact so that the magnetic device (30) polarizes the vibrating part (40); and that (ii) the vibrating part (40) is mobile relative to the magnetic device (30) in a direction parallel to the longitudinal axis (Y) under the effect of the generated mechanical force (F).

2. Electroacoustic transducer (10) according to claim 1, wherein the contact between the magnetic device (30) and the vibrating part (40) is maintained during the movement of the vibrating part (40) relative to the magnetic device (30).

3. Electroacoustic transducer (10) according to claim 2, wherein the contact between the magnetic device (30) and the vibrating part (40) is achieved by means of an elastic device (50).

4. Electroacoustic transducer (10) according to claim 3, in which the elastic device (50) has a thickness, the elasticity being obtained by means of at least one groove crossing the elastic device (50) in its thickness.

5. Electroacoustic transducer (10) according to claim 3 or 4, wherein the elastic device (50) comprises - a rigid portion (56) which is in contact with the magnetic device (30) and the vibrating part (40), and - an elastic portion (54) which is in contact with the vibrating part (40) and which is separated from the magnetic device (30) by means of a void space (29).

6. Electroacoustic transducer (10) according to any one of claims 3 to 5, wherein the elastic device (50) comprises an annular piece including the rigid portion (56) and the elastic portion (54).

7. Electroacoustic transducer (10) according to claim 5, wherein the elastic portion (54) is positioned in an inner part of the annular piece.

8. Electroacoustic transducer (10) according to any one of the preceding claims, wherein the magnetic device (30) comprises a ring magnet surrounding the coil (20).

9. Electroacoustic transducer (10) according to any one of the preceding claims, wherein the vibrating part (40) has a contact surface (42) on which is positioned an adhesive strip (49) allowing the electroacoustic transducer to be held on the skin of a user.

10. Electroacoustic transducer (10) according to any one of the preceding claims, further comprising an electronic card (70) for connecting the coil (20) to an electrical circuit.

11. Listening device (80) comprising at least one electroacoustic transducer (10) according to any one of claims 1 to 10 and a signal processing unit (82) configured to transmit an electrical signal to the coil (20), the listening device (80) being intended to be positioned around the ear of a user by positioning the vibrating part (40) in contact with a bony area.

12. Listening device (80) according to claim 11, wherein the electrical signal transmitted to the coil (20) is an outgoing electrical signal, the processing unit (82) being further configured to receive an incoming signal and process it to generate the outgoing electrical signal.

13. Listening device (80) according to claim 12, wherein the incoming signal comes from ambient sound and / or from an auxiliary electrical device connected to the listening device.

14. A bone conduction hearing aid (90) comprising a listening device (80) according to any one of claims 11 to 13, the electroacoustic transducer (10) being a first electroacoustic transducer, the hearing aid further comprising a second electroacoustic transducer (10'), the first electroacoustic transducer (10) being configured to be positioned in contact with a first bony area of ​​the head of the user and to transmit first vibrations (2) to the first bone area, and the second electroacoustic transducer (10') being configured to be positioned in contact with a second bone area of ​​the user's head and to transmit first vibrations (3) to the second bone area.

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