Patent Grant
11490215
This application claims the priority, under 35 U.S.C. § 119, of German Patent Application DE 10 2020 201 479.5, filed Feb. 6, 2020; the prior application is herewith incorporated by reference in its entirety.
The invention relates to a hearing aid, which is constructed in particular as a classical hearing aid.
Classical hearing aids, which are used to care for the hard of hearing, are typically referred to as hearing aids. In the broader meaning, however, this term also refers to devices which are provided to assist people having normal hearing. Such hearing aids are also referred to as “Personal Sound Amplification Products” or “Personal Sound Amplification Devices” (abbreviated as: “PSAD”). They are not provided to compensate for hearing losses, but rather are intentionally used to assist and improve the normal human hearing ability in specific hearing situations, for example, to assist hunters when hunting or to assist animal observation, in order to be able to better perceive animal sounds and other noises produced by animals, for sports reporters, in order to enable improved speech and/or speech comprehension in complex background noise, for musicians, in order to reduce the strain on the sense of hearing, etc.
Independently of the provided intended use, hearing aids typically include an input transducer, a data and/or signal processing unit, which typically includes an amplifier, and an output transducer as important components. The input transducer is generally formed in this case by an acousto-electrical transducer, i.e., for example by a microphone, and/or by an electromagnetic receiver, for example an induction coil. An electro-acoustic transducer is usually used as an output transducer, for example a miniature loudspeaker (also referred to as an “earpiece”), or an electromechanical transducer, for example a bone vibrator, and the data and/or signal processing unit is generally implemented by an electronic circuit implemented on a printed circuit board.
Such hearing aids furthermore typically include an antenna unit or an antenna element as a so-called RF antenna, through the use of which the hearing aid can be coupled with respect to signaling, for example, to an operating element (remote control) and/or to a further hearing aid. In general, the same antenna unit or the same antenna element is used for transmitting and receiving data for reasons of space.
In a so-called binaural hearing device, two such hearing aids or hearing aid devices are worn by a user, wherein a wireless signal connection exists between the antenna units or antenna elements of the hearing aids in operation. In operation, wireless data, possibly also large quantities of data, are exchanged or transmitted in that case between the hearing aids on the right and left ear. The exchanged data and items of information enable particularly effective adaptation of the hearing aids to a respective acoustic situation. In particular, in that way a particularly authentic room sound is enabled for the user and also the speech comprehension is improved, even in loud environments.
Hearing aids are preferably embodied to be particularly space-saving and compact, so that they can be worn as visually inconspicuously as possible by a hearing aid user. Therefore, smaller and smaller hearing aids are being produced, which have an increasingly higher level of wearing comfort and are therefore hardly perceived by a user when worn on or in an ear. Due to the structural space thus reduced, however, it is increasingly more difficult to house and/or install conventional antenna units or antenna elements for wireless signal transmission in such hearing aids.
Those problems occur in particular in the case of in-the-ear hearing aids, which are generally mass-produced and are seated deep in an auditory channel or ear channel of the hearing aid user. Such hearing aids are preferably provided with compact structural space in such a way that they are disposed to be substantially visually invisible in the ear channel in the worn state.
It is accordingly an object of the invention to provide a hearing aid, which overcomes the hereinafore-mentioned disadvantages of the heretofore-known hearing aids of this general type and which is advantageously constructed.
With the foregoing and other objects in view there is provided, in accordance with the invention, a hearing aid, in particular constructed as a classical hearing aid, including a housing having a baseplate and having a housing shell, a number of electrical and/or electronic units, and a transmitting and receiving unit for transmitting and receiving electromagnetic waves, wherein the number of electrical and/or electronic units are fastened on the baseplate, the transmitting and receiving unit includes an electronic circuit for generating a transmission signal and an antenna unit coupled thereon, the antenna unit includes a free arm, and the transmitting and receiving unit is configured to inductively feed the transmission signal of the electronic circuit into the antenna unit.
The hearing aid according to the invention is preferably constructed as a hearing aid of a type mentioned at the outset and is typically embodied as an in-the-ear hearing aid (ITE hearing aid), for example as a channel hearing aid (ITE: In-The-Ear, CIC: Completely-In-Channel, IIC: Invisible-In-The-Channel).
In this case, the hearing aid includes a housing having a baseplate, also called a faceplate, and having a housing shell. The housing is preferably formed in two parts herein and in this case the baseplate and the housing shell form the two parts.
Furthermore, the hearing aid includes a number of electrical and/or electronic units, i.e., one or more electrical and/or electronic units, also referred to as E-units in brief, wherein this number of electrical and/or electronic units are fastened on the baseplate. For example, an input transducer, i.e., for example, a microphone, forms one such E-unit. Alternatively or additionally, a battery or an accumulator forms one such E-unit and/or a data and/or signal processing unit mentioned at the outset, also referred to simply as a data processing unit hereinafter, forms a corresponding E-unit. A corresponding data processing unit typically includes an amplifier or provides an amplifier function in this case.
In addition, the hearing aid includes a transmitting and receiving unit for transmitting and receiving electromagnetic waves, wherein this includes an electronic circuit for generating a transmission signal and an antenna unit coupled thereto or an antenna element coupled thereto. This antenna unit typically includes an RF antenna of the type mentioned at the outset or forms such an antenna. Therefore, electromagnetic waves in the meaning of this application are to be understood in particular as radio signals, which are also referred to as RF signals.
The transmitting and/or receiving unit is functionally capable and configured to generate and/or evaluate RF signals transmittable or receivable by using the antenna unit. The transmission range is typically less than 18 m and is, for example, 10 m in this case. A range is to be understood in this case in particular as the signal range, i.e., a distance of the respective communication or signal connection which can exist at most between a transmitter and a receiver, so that a communication is still possible between them.
The antenna unit is furthermore preferably constructed as a radio frequency antenna (RF antenna) or as an RF resonator, for example for a 2.4 GHz Bluetooth transmission by using an ISM frequency band (ISM: Industrial, Scientific, and Medical). The antenna unit is therefore capable and configured to receive or absorb and to transmit or emit electromagnetic radio waves.
In the worn state, the hearing aid is preferably disposed substantially completely, but at least partially, in an ear channel or auditory channel of the user. The antenna element and/or the transmitting and/or receiving unit are preferably capable and configured in this case to correct attenuation and/or detuning of the RF signals due to the head of the user.
In the hearing aid according to the invention, the antenna unit includes a free arm and the transmitting and receiving unit is configured to inductively feed a transmission signal of the electronic circuit into the antenna unit. I.e., the antenna unit and the electronic circuit of the transmitting and receiving unit are galvanically separated from one another.
Inter alia, this has a positive effect on the efficiency of the antenna unit. Moreover, the transmitting and receiving unit is quasi shock resistant and or less susceptible to vibrations, since there is no electrically conductive mechanical connection, which could break, between the antenna unit and the electronic circuit of the transmitting and receiving unit.
In the meaning of this application, a free arm is to be understood in particular as an elongated conductor element or an elongated conductor track having at least one free end or free ends. Independently thereof, the antenna unit is only configured or formed for one resonance frequency, depending on the intended application. Moreover, the antenna unit only has the one free arm in some embodiment variants.
In order to enable a corresponding inductive feed or inductive coupling, the transmitting and receiving unit includes a coupling element, i.e., an inductive coupling element, which is galvanically connected to the electrical circuit and which includes a conductor loop or is formed by a conductor loop. The conductor loop or conductor hoop is formed in this case, depending on the structural variant, as a simple conductor loop or it forms one turn of a coil.
In addition, an embodiment is expedient in which the conductor loop includes an auxiliary component. The auxiliary component is in particular integrated into the conductor loop, so that the auxiliary component more or less forms a part or a segment of the conductor loop. The auxiliary component is typically an electrical component having an ohmic resistance, having a capacitance, and/or having an inductance, i.e., for example a capacitor, a coil, a resistor, or simply a conductor interruption, i.e., a quasi-gap.
In one advantageous refinement, the coupling element includes two conductor loops disposed adjacent to one another. The two conductor loops are preferably not disposed coaxially and in particular enclose two surfaces spatially separated from one another. It is expedient in this case if the transmitting and receiving unit is configured in such a way that opposing rotational directions for the courses or paths of the current of a transmission signal through the two conductor loops are predetermined for the two conductor loops. In this way, magnetic fields having opposing magnetic field directions are then generated using the two conductor loops.
Depending on the embodiment variant, the two conductor loops are furthermore formed as simple conductor loops or each of the two conductor loops forms one turn of a coil, so that in this case two coils are disposed adjacent to one another.
In addition, an embodiment is expedient in which each of the two conductor loops includes an auxiliary component of the above-mentioned type. The two conductor loops preferably have identical auxiliary components to implement a symmetrical structure.
Furthermore, an embodiment variant is preferred in which the coupling element includes a shared supply line, in particular an elongated supply line, for the two conductor loops, which the two conductor loops adjoin. In addition, the two conductor loops are preferably symmetrically formed and the shared supply line is preferably in the plane of symmetry. According to one embodiment variant, the supply line has an auxiliary component of the above-described type in this case.
Depending on the intended application, the two conductor loops are moreover connected through a connecting element to the electronic circuit of the transmitting and receiving unit, wherein the connecting element is preferably constructed as a waveguide or as a coaxial cable. If the connecting element is constructed as a waveguide, the waveguide is thus typically constructed as a coplanar waveguide and in particular includes three conductor strips. These are expediently disposed in parallel to one another, wherein the middle conductor strip is then typically connected to the shared supply line and the outer conductor strips are each connected to one of the two conductor loops. With such an embodiment, in operation of the transmitting and receiving unit, the feed or readout of a signal typically takes place through the middle conductor strip and a ground potential or reference potential is predetermined for the outer conductor strips.
Furthermore, the antenna unit typically includes a feed arm and the above-mentioned two conductor loops are preferably disposed symmetrically in relation to the feed arm. In particular, an embodiment is favorable in this case in which the above-mentioned shared supply line is aligned and positioned in parallel to the feed arm. Depending on the application, the feed arm, either alone or together with a conductor structure adjoining thereon, additionally forms an S-shaped or Z-shaped conductor structure. Independently thereof, the supply line includes an auxiliary component of the above-described type in some cases.
According to a further embodiment variant, the antenna unit includes an electrically conductive auxiliary element, which is constructed in particular for shielding the free arm against the number of electrical and/or electronic units. A ground potential or reference potential is preferably predetermined for the auxiliary element in operation of the hearing aid, wherein the electrically conductive auxiliary element is electrically conductively connected, for example, to a battery of the hearing aid for this purpose.
In particular due to the shielding effect of the auxiliary element, freedoms advantageously result in the configuration of the hearing aid and in particular in the configuration of the antenna unit in such a way that possible interference frequencies from the E-units do not have to be taken into consideration in the selection of the resonance frequencies or the resonance frequency for the antenna unit, so that the antenna unit and E-units can be optimized quasi-independently of one another.
The possibility is thus provided, for example, of using a simpler amplifier or a simpler amplifier function and thus a simpler data processing unit for the amplification of transmission signals and/or reception signals. In at least one application, the hearing aid then also includes such a simpler amplifier or a simpler data processing unit. Moreover, a corresponding amplifier may be positioned more freely, i.e., the selection of a suitable position for the amplifier is to be taken into consideration less. Reference is typically made in such cases to a “floating amplifier.”
Due to the additional freedoms in the specification of the resonance frequency or the resonance frequencies, it is moreover possible in some cases to dispense with adaptation elements, for example an ohmic resistor, a coil, a capacitor, and/or a balun, and in the case of at least one embodiment, the antenna unit also does not have such an adaptation element. I.e., in at least one application an adaptation element of the above-mentioned type is omitted in the hearing aid according to the invention.
Notwithstanding this, the auxiliary element is expediently positioned between the free arm and the number of E-units. Moreover, the auxiliary element is preferably positioned between the free arm and the electronic circuit of the transmitting and receiving unit.
Furthermore, an embodiment is advantageous in which the auxiliary element includes or forms a curved conductor, a conductor loop, or a conductor hoop. If the shielding element includes a conductor loop or conductor hoop, the number of E-units is thus expediently positioned within the conductor loop or the conductor hoop and/or the electronic circuit of the transmitting and receiving unit is positioned within the conductor loop or the conductor hoop. If the shielding element includes a curved conductor, this typically thus at least partially encloses the number of E-units and/or the electronic circuit of the transmitting and receiving unit. Moreover, a geometry of the auxiliary element is advantageous in which the auxiliary element is formed at least approximately annularly, i.e., has a ring shape. However, in this case the geometry does not necessarily correspond to a geometrical circle. Moreover, the ring shape is also not necessarily closed. However, the curved conductor, the conductor loop, or the conductor hoop preferably spans at least an arc range or angle range of at least 120°, more preferably of at least 180°, and in particular of at least 250° or of at least 300°.
In particular if the auxiliary element includes a type of conductor loop, it is moreover advantageous if the free arm at least partially encloses the auxiliary element and at the same time, for example, spans or covers an arc range or angle range of at least 90°. The course of the free arm in at least one section then furthermore preferably follows the course of the auxiliary element in a good approximation, wherein the free arm moreover preferably extends at approximately equal distance from the auxiliary element in this region.
Furthermore, an embodiment variant is preferred in which the free arm is connected through a short-circuit arm to the auxiliary element. The short-circuit arm is typically connected at a first end of the free arm to the free arm in this case. According to one embodiment variant, the short-circuit arm furthermore includes an auxiliary component of the above-described type.
In addition, the free arm is preferably connected through the above-mentioned feed arm to the auxiliary element and/or through an auxiliary component of the above-described type.
Furthermore, an embodiment variant is expedient in which the auxiliary element and/or the free arm has a widened free end. Widened is to be understood in particular to mean that the corresponding free end or the corresponding exposed end has a transverse extension which corresponds to at least 1.2 times, preferably at least 1.5 times, and more preferably at least 2 times the transverse extension away from the free end.
Notwithstanding this, it is expedient if the auxiliary element and/or the free arm includes an auxiliary component of the above-described type.
Furthermore, embodiment variants are favorable in which an additional arm branches off from the free arm and in particular does so spaced apart from the ends of the free arm. The additional arm is constructed herein in the case of some embodiments as a further free arm, i.e., as an elongated conductor having a free end, and includes, for example, a widened end of the above-mentioned type and/or an auxiliary component of the above-mentioned type.
In one advantageous refinement, the antenna unit is constructed like a so-called PIF antenna (Planar Inverted F-shaped antenna). In this case, a ground potential or reference potential is then typically predetermined for the auxiliary element in operation of the hearing aid. An above-mentioned short-circuit arm, an above-mentioned feed arm, and the free arm then typically form an F-shaped main pattern made of a conductive material, for example copper.
Furthermore, an embodiment is preferred in which at least a part of the antenna unit, in particular the complete antenna unit, and/or at least a part of the coupling element, in particular the complete coupling element, only has a very small extension in one spatial direction, typically less than or equal to 1 mm. Furthermore, the at least one part of the antenna unit, in particular the complete antenna unit, and/or the at least one part of the coupling element, in particular the complete coupling element, is preferably substantially in a plane, the normal of which is aligned in parallel to this spatial direction. Then, for example, at least a part of the free arm and/or at least the free arm and/or at least the above-mentioned auxiliary element is thus substantially in one plane. Alternatively or additionally, for example, the above-mentioned conductor loop of the coupling element or the above-mentioned two conductor loops are substantially in one plane.
In addition, an embodiment is advantageous in which the antenna unit is formed by conductor tracks or includes at least a number of conductor tracks, which are applied to a substrate or to the baseplate, for example, and which form, for example, at least a part of the free arm and/or at least the free arm and/or at least the above-mentioned auxiliary element.
Furthermore, it is advantageous if the coupling element is formed by a number of conductor tracks or includes at least a number of conductor tracks which are applied, for example, to a substrate or to the baseplate, and which form, for example, at least the above-mentioned conductor loop or the above-mentioned two conductor loops.
In one advantageous refinement, the transmitting and receiving unit includes a number of conductor tracks which are applied to a shared substrate, wherein a first portion of these conductor tracks forms at least a part of the antenna unit, a second portion of these conductor tracks forms at least a part of the coupling element, the first portion is applied to a first side of the substrate and the second portion is applied to an opposite second side of the substrate.
Independently thereof, corresponding conductor tracks are, for example, printed on or applied with the aid of a coating method. In this case, for example, a film or a flexible printed circuit board (flexible PCB) is used as the substrate, if used.
Furthermore, a modification or refinement of the antenna unit is expedient in which the free arm is formed as an expanded free arm and in this case includes a conductor expansion made of an electrically conductive material, by which, for example, a branch or fork is formed. Through the use of the conductor expansion, the free arm is preferably capacitively charged starting from an embodiment of the free arm without conductor expansion and in this way a resonance condition for the antenna unit is typically predetermined.
A corresponding conductor expansion is preferably, but not necessarily, not formed by conductor tracks and is also not in the above-mentioned plane, which is predetermined in particular by a surface of the above-mentioned substrate. Instead, the conductor expansion is preferably more or less guided or tilted out of this plane.
The conductor expansion is typically formed, inter alia, by a connecting arm, which protrudes from the substrate and is connected to a conductor track end or a widened conductor track end of a conductor track on the substrate. The corresponding conductor track then forms the free arm together with the conductor expansion. A cross conductor, for example, which then forms a T shape together with the connecting arm, adjoins the connecting arm. Depending on the application, a U-shaped conductor element in turn adjoins the cross conductor at each of the two ends, wherein the opening of the U shape preferably faces toward the substrate.
According to a further embodiment variant, an above-described conductor expansion is not part of the free arm but part of the above-described additional arm or adjoins the above-described additional arm.
It is additionally expedient if a ground potential or reference potential for the above-mentioned auxiliary element is predetermined in operation of the hearing aid, for example by a battery or an accumulator, and if the auxiliary element quasi-relays this potential to at least one of the above-mentioned E-units, for example the data processing unit of the hearing aid.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a hearing aid, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
Referring now in detail to the figures of the drawings, in which parts corresponding to one another are each provided with the same reference signs, and first, particularly, to
Furthermore, in the exemplary embodiment, a number of electrical and/or electronic units, referred to below as E-units 10 for short, are fastened on the baseplate 6. In the exemplary embodiment, a battery 12 and a data processing unit 14 each form one of these E-units 10. A further E-unit 10, i.e., a further additional one of the number of E-units 10, is formed by an electronic circuit 16 of a transmitting and receiving unit 18.
In this case, the transmitting and receiving unit 18 is configured to transmit and receive electromagnetic waves in operation of the hearing aid 2, in particular for communication with a second hearing aid (not shown). The electronic circuit 16 and an antenna unit 20, which is shown in a first embodiment in
This antenna unit 20 is preferably configured like a so-called PIF antenna and typically includes an electrically conductive auxiliary element 22, for which a ground potential or reference potential is preferably predetermined in operation of the hearing aid 2. In the exemplary embodiment according to
The auxiliary element 22 and the free arm 24 are in one plane in this case and are each formed as conductor tracks, for example made of copper. Furthermore, these conductor tracks are applied, for example printed, on a first side of a substrate 26. This first side is shown in
In the exemplary embodiment according to
In order to feed a signal to be transmitted into the antenna unit 20 or to read out a received signal, the transmitting and receiving unit 18 furthermore includes a coupling element 32. The coupling element 32 is also formed by conductor tracks in the exemplary embodiment and these conductor tracks are applied in this embodiment variant on the same substrate 26 as the antenna unit 20, but on the second side of the substrate 26 opposite to the first side. This second side is shown in a first embodiment in
In the exemplary embodiment according to
The coupling element 32 is connected to the electronic circuit 16 of the transmitting and receiving unit 18 through a connecting element 38. This connecting element 38 is constructed in the exemplary embodiment as a coplanar waveguide, which includes three conductor strips 40. The three conductor strips 40 are disposed in parallel to one another and coplanar in this case and the outer two outer conductor strips 40 are each connected to one of the conductor loops 34. The middle conductor strip 40 is additionally connected to the supply line 36 and a signal is fed in or read out therethrough in operation of the transmitting and receiving unit 18 as needed.
The conductor strips 40 are preferably supplemented by a conductor surface 42, which is applied in particular to the first side of the substrate 30 and which is subjected in operation of the transmitting and receiving unit 18, like the two outer conductor strips 40, to a ground potential or reference potential. This ground potential or reference potential is provided in this case by the electronic circuit 16 of the transmitting and receiving unit 18 and is supplied through a galvanic connection.
As already mentioned above, the auxiliary element 22 is preferably also subjected to a ground potential or reference potential, but in the exemplary embodiment this is provided through a galvanic connection to the battery 12. The auxiliary element 22 and the coupling element 32 are galvanically separated from one another.
A second embodiment of the coupling element 32 is shown in
Independently thereof, an auxiliary component 44 in the meaning of this application is typically an electrical component having an ohmic resistance, having a capacitance, and/or having an inductance, i.e., for example a capacitor, a coil, a resistor, or simply a conductor interruption, i.e., a quasi-gap.
A third embodiment of the coupling element 32 is shown in
Further embodiment variants of the antenna unit 20 are shown in
The term “widened” is to be understood in particular to mean that the corresponding free end has a transverse extension which corresponds to at least 1.2 times, preferably at least 1.5 times, and more preferably at least 2 times the transverse extension of the corresponding conductor element away from the free end.
A third embodiment variant according to
A fourth variant is illustrated in
The further embodiment variants of the antenna unit 20 according to
The embodiment variant of the antenna unit 20 according to
In this exemplary embodiment, in contrast to the auxiliary element 22, the feed arm 30, and the remainder of the free arm 24, the conductor expansion 62 is not formed by conductor tracks and is also not in the above-mentioned plane, which is predetermined by a surface of the substrate 26. Instead, the conductor expansion 62 is more or less guided or tilted out of this plane. The conductor expansion 62 is formed in the exemplary embodiment, inter alia, by a connecting arm, which protrudes from the substrate 26 and is connected to a conductor track end or a widened conductor track end of a conductor track on the substrate. The corresponding conductor track also forms the free arm 24 in the embodiment of the antenna unit 20 according to
A cross conductor, which forms a T-shape together with the connecting arm, adjoins the connecting arm in the exemplary embodiment according to
According to a further embodiment variant (not shown), an above-described conductor expansion 62 is not part of the free arm 24 but part of the above-described additional arm 52 or adjoins the above-described additional arm 52.
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