EP3579336B1 - Antenna and device incorporating the same - Google Patents

Description

The invention relates to an antenna for the inductive transmission of information and/or energy, having a film-like antenna base body with a central coil core section that carries a coil. The invention also relates to a device, in particular a hearing aid, with such an antenna. The hearing device is preferably a hearing aid device.

Persons who suffer from a reduction in hearing use, for example, a hearing aid device as an auxiliary instrument. The sound or a sound signal from the environment is recorded by an electromechanical sound converter, which converts the sound or the sound signal into an electrical signal (audio signal). The electrical signal is processed by an amplifier circuit and converted by another electromechanical transducer into an amplified sound signal that is introduced into the person's ear canal.

Different versions of hearing aid devices are known. So-called "behind-the-ear devices" are worn between the skull and the auricle, with the amplified sound signal being introduced into the person's auditory canal by means of a sound tube. A further embodiment of a hearing aid device is an "in-the-ear device" in which the hearing aid device itself is inserted into the auditory canal. As a result, the auditory canal is at least partially closed, so that with the exception of the sound signal generated by the hearing aid device, no further sound or only strongly damped sound can penetrate into the auditory canal.

If the person suffers from impaired hearing in both ears, a hearing aid device system with two such hearing aid devices is used, one of the two hearing aid devices being assigned to each ear. In order to enable the person to hear spatially or to improve it, it is necessary for the audio signals recorded with one hearing aid device to be made available to the other hearing aid device in each case. Information is transmitted between the two hearing aids wirelessly using an antenna. Attenuation of the transmitted information due to the person's head increases with increasing frequency. Because of this, inductive information transmission, for example with a frequency between 1 kHz and 300 MHz, is used in particular.

In the WO 2017/153274 discloses an antenna, in particular of a hearing aid device, for radio communication. This includes a longitudinally extending coil core that carries a number of windings, and a flat first shield made of a ferrimagnetic and/or ferromagnetic material on an end face of the coil core, which is angled to the longitudinal direction of the coil core. According to a development of the antenna, a second flat shield is arranged on the end face facing away from the first shield, which is angled to the longitudinal direction of the coil core.

During operation, such an antenna generates a magnetic field with a magnetic dipole moment for the inductive transmission of information. In relation to the antenna, this is fixedly oriented in a (transmission) spatial direction. For the strongest possible inductive coupling and thus for the best possible transmission quality between the antenna and a receiver, in particular an antenna or a coil of a second hearing aid device or an accessory, the receiver must have a corresponding orientation (alignment) with respect to the spatial transmission direction. In particular, a (receiving) surface of the receiver is oriented perpendicularly to the spatial direction of the transmitter in order to generate an induction.

Information is inductively transmitted or exchanged between the hearing aid or between at least one of the hearing aids of a hearing aid system and the accessory, such as a remote control or a relay station for coupling the hearing aid to another device such as a mobile phone. In this case, the hearing aid device can be rotated relative to the accessory, for example due to a rotation of the head. The receiver, which is typically arranged rigidly in or on the accessory, is also moved or rotated. Consequently, the magnetic field generated by the antenna and in particular its magnetic dipole moment is rotated relative to the receiver, so that inductive coupling and correspondingly the information transmission is comparatively reduced or even essentially zero compared to the optimal position of the receiver with respect to the spatial direction of the magnetic dipole .

This problem also occurs in an analogous manner with other devices, such as a sensor (sensor technology), a computer system worn on the body (wearable computer, wearables), a component of a sensor or actuator system worn on the body (body-area network) or with hearing aids, such as headphones or a headset. For example, a second antenna can be used in addition to the (first) antenna, the spatial transmission direction of the second antenna being oriented at an angle to the spatial transmission direction of the first antenna. The second antenna in the device is preferably arranged at a distance from the first antenna and is oriented in such a way that mutual interference is prevented. A second antenna requires additional installation space, which is why a structure that is comparatively complex or even unusable for the intended use of the device is necessary.

In the WO 2010/013992 A1 a thin, helical, tape coil is known as an antenna, in which metal wire is wound on a rod-shaped tape substrate.

the JP 2007028114A describes an antenna of magnetic material, with a plurality of coils, whose magnetic layer is a square or rectangular has shape. The coils are arranged radially in a plane at an almost equal pitch in the axial direction of the coils, and the one-side ends of all the coils facing each other are connected through the magnetic layer.

the WO 2017/153274 A1 discloses an antenna with a coil core oriented in the longitudinal direction, which carries a number of coil turns, and with a flat screen made of a ferrimagnetic or ferromagnetic material arranged on one end face.

In the EP 3 113 316 A1 describes a power source device having a power receiving module. The power receiving module includes a power extraction coil and a power receiving resonant coil, and a part or all of a circuit board and/or a secondary battery is located inside the power extraction coil and the power receiving resonant coil of the power receiving module.

The invention is based on the object of specifying an antenna which enables comparatively reliable inductive coupling to a receiver even in the case of different spatial orientations. Furthermore, a device with such an antenna is to be specified, as well as a method for operating such an antenna.

With regard to the antenna, this object is achieved according to the invention by the features of claim 1. With regard to the method, this object is achieved by the features of claim 7 and with regard to the device, this object is achieved by the features of claim 8. Advantageous refinements and developments are subject matter of the dependent claims.

The antenna is suitable, in particular provided and/or set up, to be used in an inductive transmission of information and/or energy. In this case, the antenna is, for example, a component of a hearing device, in particular a hearing aid device. The antenna has a foil-like, preferably continuous, Antenna body with a middle coil core section and with both sides of the middle coil core section arranged opposite to each other outer antenna sections. In this case, the central coil core section carries a first coil (main coil). Preferably, the outer antenna sections are planar. In addition, the outer antenna sections each have a coil core section on the edge that adjoins the central coil core section and carries a second coil (secondary coil). For example, the first and the second coils have different numbers of turns.

The outer antenna sections are angled relative to the center coil core section. The first coil and the two second coils are therefore oriented in different spatial directions, in other words the coil axes of the first and the two second coils are angled relative to one another. The coil core sections on the edge are oriented perpendicularly to the central coil core section, forming a U-shape. Thus, the outer antenna sections each form a U-leg of the U-shape and the central coil core section forms the U-connection leg of the U-shape. In this case, the U-connecting leg extends in a longitudinal direction and the U-legs in a transverse direction. The film-like two outer antenna sections extend in two mutually parallel and spaced apart planes.

Transmission of information is understood here in particular as transmission of a signal or transmission of data, such as setting data or data which include information about sound detected by the hearing aid device or a sound signal processed using signal technology. The energy received during the energy transmission is preferably made available for charging an energy store, in particular a battery.

A film-like object is to be understood here as meaning that it has an extent in a spatial direction which is comparatively small in comparison to its extent in a plane oriented perpendicularly to this spatial direction. In other words, the antenna base body is flat. In this case, the two-dimensional sides are each referred to as the broad side.

Those broadsides of the central coil core section and the two outer antenna sections which face the two outer antenna sections or the central coil core section are also referred to below as the inside of the respective section, and the other broadsides as the outsides. The area encompassed at least partially by the antenna base body forms an inner area.

Furthermore, due to the angling (folding) of the outer antenna sections in relation to the central coil core section and due to the foil-like, i.e. flat design of the antenna base body, its space requirement is reduced, so that a comparatively compact antenna is provided, which can therefore also be used in devices that offer only little installation space, in particular a hearing aid device, can be arranged.

The antenna base body is preferably made of a ferromagnetic and/or ferrimagnetic material, in particular a soft magnetic ferrite, and has an electrical conductivity of less than 10 ⁶ S/m, preferably less than 100 S/m, and a magnetic permeability μ _r >5 , preferably µ _r >200. For example, the antenna base body is a film or is formed by means of a film. For example, the thickness of the film, ie its extent perpendicular to the broad side, is between 25 μm and 700 μm, in particular between 70 μm and 300 μm, preferably between 100 μm and 250 μm. The antenna body is preferably bendable or foldable. Consequently, the antenna base body can be angled, starting from a planar shape, by angling the two outer antenna sections.

The first coil and each of the second coils can advantageously be switched (activated) independently of one another, ie can be supplied with electric current with a corresponding current direction. For this purpose, the first and the second coil are expediently connected to a current or voltage source. The first coil, one of the second coils, each individually or a combination of these coils, can therefore each be connected with a designated direction of current.

For example, in a first operating mode, the first and the two second coils can be switched simultaneously, with the current direction being chosen such that the magnetic fields generated by the coils overlap constructively, i.e. the north pole of the magnetic field generated by the first coil is adjacent to the south pole of the by means of a second coil and the south pole of the magnetic field generated by the first coil is arranged adjacent to the north pole of the magnetic field generated by another second coil. So the current flows through the coils in the same sense. With such switching of the coils and with a U-shape of the antenna base body, the antenna acts like a ferrite rod antenna with a comparatively large end face, with the magnetic dipole moment generated being oriented essentially perpendicularly to the outer antenna sections.

For example, only one of the two second coils is switched in a second operating mode. With a U-shape of the antenna base body, the generated magnetic dipole moment is not perpendicular to the outer antenna sections, but tilted at an angle to the normal of the outer antenna sections.

In summary, the spatial transmission direction or the orientation of the magnetic dipole moment generated by means of the antenna with respect to the antenna is not fixed (rigid), but is spatially differently oriented depending on the switching of the coils. In other words, a radiation characteristic of the antenna can be set and adjusted depending on the switching of the coils. In other words, the magnetic field generated by the antenna is rotated. The orientation of the magnetic dipole moment is adjusted by activating, in particular by energizing, one of the second coils, both second coils and/or the first coil in such a way that the strongest possible inductive coupling between the antenna and the receiver is realized. If the receiver is a coil, for example, the first coil and second coils are energized in such a way that the magnetic dipole moment generated by the antenna runs as parallel as possible to a coil axis or as perpendicular as possible to a receiving surface of the receiver.

Advantageously, comparatively little installation space is required for the antenna. Furthermore, it is comparatively simple and can therefore also be produced in a cost-saving manner.

For information and/or energy transmission, the antenna is (magnetically) inductively coupled to a receiver due to the magnetic dipole moment generated by it, the receiver being in particular a second antenna or a coil. The receiver is in particular an accessory such as a remote control or a relay station, in particular worn on the body.

When this receiver is rotated with respect to the spatial direction of the transmitter, the strength of the magnetic inductive coupling changes. Advantageously, the antenna according to the invention makes it possible, in particular if the magnetically inductive coupling is comparatively low, to change the orientation of the spatial transmission direction by changing the circuit (control), in other words by changing the current strength and/or the direction of the current, of the coils to change. The spatial direction of the transmitter is preferably adapted in accordance with the changed spatial orientation of the receiver. For example, in the case of a receiver designed as a coil, the magnetic dipole moment is aligned parallel to the coil axis of the receiver. Even if the magnetic dipole moment cannot be set completely according to the receiver, for example if the receiver is rotated comparatively strongly with respect to the antenna, in particular 90° with respect to the antenna, the change in the spatial orientation of the magnetic dipole moment makes it possible for a comparatively large part of the magnetic dipole moment contributes to the magnetic coupling. In summary, changing the spatial orientation of the magnetic dipole makes it possible for the magnetically inductive coupling to be adjusted in such a way that adequate information transmission is realized.

For example, the device having the receiver, in particular the accessory, or alternatively a device having the antenna, in particular the hearing aid device, has an evaluation unit (signal processing unit) which, using a suitable algorithm, such as a channel estimation algorithm or the so-called BER evaluation (bit -Error rate evaluation), the strength of the inductive coupling is determined so that, depending on the result of the determination, the switching or activation of the coils is changed if necessary for sufficient transmission quality between antenna and receiver.

According to an advantageous development, each of the two outer antenna sections has a flange section, in particular in the form of a segment of a circle. This adjoins the free-end side, that is to say on the end face opposite and/or facing away from the central coil core section, of the peripheral coil core section. In other words, the outer antenna section is expanded starting from the free end side of its peripheral coil core section, in particular in the shape of a circular segment, with the peripheral coil core section and the flange section extending in a common plane. In other words, the outer antenna section is in the shape of a mushroom head when the expansion is in the form of a segment of a circle. Alternatively, expansion is rectangular, T-shaped, circular, or ring-shaped. An effective antenna area is advantageously widened or enlarged by means of the flange areas.

According to a particularly advantageous development, the antenna has a preferably one-piece, foil-like shield. This is arranged in each case on the side of the two outer antenna sections facing the middle coil core section and on the side of the middle coil core section facing the outer antenna sections. In other words, the shielding is arranged on the respective inner side of the outer antenna sections and the central coil core section.

According to a further development, the shielding is larger than or equal to the antenna base body and covers it. In other words, the shield an extension in a plane parallel to the outer antenna sections or to the middle coil core section, which is greater than or equal to the extension of the outer antenna section or the middle coil core section.

The shielding preferably has an electrical conductivity greater than 10 ⁶ S/m. In addition, the shielding has a (magnetic) permeability μ _r <1000, in particular μ _r <100, preferably μ _r <2. The shielding is therefore formed from a diamagnetic (0≦μ _r <1) or paramagnetic (μ _r >1) material, in particular copper, or contains diamagnetic or paramagnetic material. The thickness of the shielding is selected in such a way that penetration of the shielding by the magnetic field generated by the antenna is avoided. For example, the shield has a thickness between 0.25 and 1.5 times the penetration depth of the magnetic field for the material of the shield.

The permeability of the antenna base body is preferably greater than the permeability of the shielding, and the electrical conductivity of the material of the shielding is expediently greater than the electrical conductivity of the antenna base body. The magnetic field does not penetrate into the shielding, but is forced out of it, in particular due to a current induced in the surface of the shielding according to Lentz's law and a corresponding opposing magnetic field. The magnetic field is pushed into the antenna base body and thus essentially runs there. The shielding prevents the magnetic field lines from spreading into the interior. Because of this, an effective permeability of the antenna base body and the sensitivity of the antenna are advantageously increased.

The sensitivity and the quality of the antenna can be adapted to operational requirements by the design, in particular its extension, of the antenna base body in relation to the shielding. For example, external antenna sections that are smaller than the shielding result in an improved quality of the antenna, which is advantageously only slightly reduced Sensitivity. In particular, the magnetic field lines are deflected away from the inner area or penetration of the magnetic field lines into the inner area is avoided. Outer antenna sections that are smaller than the shield mean that a projection of the outer antenna sections onto the shield is completely covered by the latter.

The spatial orientations of the magnetic dipole moment generated by means of the antenna that can be realized by means of a corresponding circuit or control of the coils are dependent on the design of the antenna, in particular the angle between the middle coil core section and the respective outer antenna section, the shape of the flange sections and the shape of the shielding . If typical or comparatively frequently occurring rotations are provided or expected during operation between the antenna and the receiver, the antenna is preferably arranged in a device carrying it, for example a hearing aid device, in such a way that such rotations are compensated for by means of a corresponding change in the magnetic dipole moment - under Considering the design of the antenna and thus the realizable spatial orientations - can and will be compensated as far as possible, the inductive coupling is and remains as strong as possible. For example, rotations of a person's head typically occur more frequently and/or at greater angles than head tilts. The antenna is then preferably arranged in a hearing aid device in such a way that the best possible (strongest) inductive coupling between the antenna of the hearing aid device and the receiver of an accessory part is made possible during such rotations by a corresponding adaptation of the spatial orientation of the magnetic dipole moment for these rotations.

For example, the first coil and/or the second coils are wound around the not yet folded antenna base body formed from a foldable film using a winding machine, and the coils are connected to corresponding electrical connections, for example by means of bonding. For example, the shielding in the form of copper foil is then arranged on the antenna base body and the antenna base body and the copper foil are folded.

Alternatively, the antenna base body is formed by means of a rigid and already angled ferrite core. The first coil is applied using the winding machine. The second coils are pre-wound and then pushed onto the coil core sections at the edge. If the outer antenna sections have flange sections, these are designed in such a way that the second coils can be plugged onto the edge-side coil core sections via these.

Alternatively and preferably, however, according to a suitable development, the antenna base body is integrated into the printed circuit board. In the course of the manufacture of the antenna, the shielding is glued to that side of the printed circuit board which is intended to face the interior.

In a further alternative, the shielding and the antenna base body are integrated into a preferably flexible printed circuit board. At most, a first winding layer and a second winding layer are arranged on opposite broad sides of the antenna base body. In other words, the antenna base body, the first winding layer and the second winding layer are stacked one on top of the other. In particular, the antenna base body and the winding layers form layers of the printed circuit board. For example, in the course of the production of the printed circuit board, the layers are glued or laminated onto a substrate or onto one of the layers.

These each have a number of conductor tracks, by means of which the turns of the first coil and the turns of the second coil are formed. The conductor tracks run essentially perpendicularly to the longitudinal direction or to the transverse direction. The conductor tracks of the two winding layers are electrically (galvanically) connected to one another to form the corresponding coil by means of vias, which extend in a suitable manner perpendicular to the broad side of the antenna base body. For example, the conductor tracks are introduced into the corresponding winding layer in the course of the production of the printed circuit board by means of etching or by means of a lithography process.

The shielding is expediently formed by means of a copper layer of the printed circuit board and is arranged on the side of the antenna base body facing the interior area and on the broad side of the first winding layer facing away from the antenna base body. In the course of production, the antenna base body and/or the winding layers are applied, for example, by means of lamination or alternatively by means of coating. For example, the antenna base body and/or the winding layers are applied to one of the layers or to a carrier structure.

For example, the winding layers are formed only in the area of the central coil core section and the peripheral coil core sections. Alternatively, the winding layers cover the antenna base completely, i.e. over the entire area of the antenna base.

The printed circuit board has, for example, a (thickness) extent perpendicular to its broad side of between 75 μm and 850 μm, in particular between 120 μm and 450 μm, preferably between 150 μm and 400 μm. As explained above, the antenna base body integrated into the printed circuit board has a thickness of between 25 μm and 700 μm, in particular between 70 μm and 300 μm, preferably between 100 and 250 μm.

An essentially field-free area is advantageously formed, particularly centrally, on the insides of the shielding arranged on the outer antenna sections. An electrical or electronic device component of a device having the antenna can advantageously be connected here. For example, the electronic device component is charging electronics in the form of a charging chip, a radio system chip and/or connections for an energy store. In this case, the electronic device component is preferably arranged centrally on the circuit board side (surface) facing the inner area of a section of the circuit board in which the outer antenna sections are integrated. As a result, the electronic device component is positioned in a substantially field-free manner and is not disturbed, or only to a small extent, due to the magnetic fields. Such an electronic device component is also disruptive a signal-to-noise ratio of the antenna during operation or only to a comparatively low extent, ie the antenna and the electronic device component have a comparatively low level of crosstalk. The electronic device component can also be applied to the printed circuit board in a simple and cost-effective manner, for example by reflow soldering.

According to an advantageous embodiment, the antenna has a third winding layer and a fourth winding layer, which are arranged on the broad side of the first winding layer facing away from the antenna base body or on the broad side of the second winding layer facing away from the antenna base body. In this case, the third winding layer is expediently arranged between the first winding layer and the shielding. Analogous to the first winding layer and the second winding layer, the third winding layer and the fourth winding layer have conductor tracks. A third coil is formed by means of the conductor tracks of the third winding layer and by means of the conductor tracks of the fourth winding layer, which coil is arranged concentrically with respect to the first coil or with respect to one of the second coils. In other words, the third coil is a further first coil or a further second coil. For example, three third coils are formed in an analogous manner, which are arranged concentrically with respect to the first coil or the two second coils. The coils can preferably be switched or controlled independently of one another. In this way, the spatial transmission direction of the antenna can be set and set more precisely with a corresponding switching (current supply, activation) of the coils. Alternatively, the third coil is galvanically connected to the corresponding first coil or to the corresponding second coil to form a single winding.

Alternatively or additionally, one or more further first coils is or are carried by the central coil core section, the further first coils being arranged next to one another in the longitudinal direction or in the longitudinal direction of the coil. Alternatively or additionally, one or more other second coils are carried by one or both edge-side coil core sections, with the other second coils being arranged next to one another in the transverse direction or in the longitudinal direction of the coil are. In this case, the coils can likewise be switched independently of one another, so that with a corresponding switching of the coils the spatial transmission direction of the antenna can and is set more precisely.

Advantageously, (electrical) contacting of the coils during production is comparatively simple. In particular, no additional work step for contacting is necessary, but is already taken into account in the design (layout) of the circuit board. Because of this, the contacting of the coils also requires no soldering pad, so that the space requirement is advantageously reduced.

For example, in an analogous manner, the printed circuit board has further winding layers to form further coils arranged concentrically to the first coil and to the third coil or to the second coil and to the third coil.

In the case of a flexible printed circuit board, it is possible for this and thus the integrated antenna base body to be angled (folded) in the course of assembly or manufacture. Furthermore, when the shielding and the antenna base body are integrated into a particularly flexible printed circuit board, the antenna is advantageously of comparatively stable design and can therefore be installed in a device with comparatively little effort.

As an alternative to integrating both the shielding and the antenna base body, only the shielding is integrated into the printed circuit board. The printed circuit board is then expediently arranged on the side of the antenna base body and the coils that faces the interior area.

In an advantageous embodiment, a device has an antenna in one of the variants presented above. In particular, the antenna is used for wireless inductive information and/or energy transmission, the antenna having a first coil, which is wound around a central coil core section of a film-like antenna base body, and second coils, which have a Angle, in particular 90 ° to the first coil, are each wound around a peripheral coil core portion of the film-like antenna body.

The device is, for example, a sensor (sensor system) such as a blood pressure, blood sugar or heart rate monitor or a computer system worn on the body (wearable computer, wearables) or a component of a sensor or actuator system worn on the body (body-area network). In particular, the device is a hearing device, such as headphones or a headset, and the device is preferably a hearing aid device. The hearing aid can be, for example, a receiver-in-the-canal (RIC) hearing aid, an in-the-ear (ITE) hearing aid, an in-the-canal (ITC) hearing aid complete-in-canal (CIC) hearing aid or a behind-the-ear (BTE) hearing aid worn behind an ear cup. The hearing aid device can be part of a (binaural) hearing aid device system, such a hearing aid device being assigned to each ear of a person.

The device, in particular the hearing aid device, can be assigned an accessory, such as a remote control or a portable relay station, which is at least temporarily inductively coupled to the device for inductive information and/or energy transmission. The accessory device also has, for example, an antenna in the variants presented above.

For example, the outer antenna sections extend over other areas of the device, for example over the entire device. Due to the foil-like design, the antenna is enlarged in a space-saving and cost-effective manner, as a result of which a bandwidth or the quality and the sensitivity of the antenna can be adapted to the operational requirements.

According to an advantageous development, the antenna encompasses a device component at least in sections. The device component is thus arranged in the interior of the antenna. A space-saving embodiment is formed by arranging the antenna practically directly on the device component. As a result, the device designed in particular as a hearing aid can remain the same Sensitivity of the antenna can be made smaller, or additional components can be installed in the device.

The outer antenna sections, in particular their flange sections, are adapted to a shape of the device component, for example. For example, the flange section is not flat but curved. Alternatively, the flange section has a recess, for example for contacting the device component.

The device component is in particular an energy store such as a battery, in particular a lithium-ion accumulator, which is used to supply energy to the hearing aid. In this case, the antenna is used for inductive energy transmission, so that in a specific operating mode of the device wireless (wireless) charging of the energy store of the device is made possible by means of the antenna.

In particular, if the device component is designed as an energy storage device, the device component has essentially parallel and spaced-apart end faces (end faces) and a peripheral region which is formed by means of a peripheral lateral surface perpendicular to the end faces of the device component. Then, according to a suitable development, the outer antenna sections are each arranged on the end faces of the device component and the central coil core section covers the lateral surface of the device component. The outer antenna sections cover the end face of the respective end at least partially, preferably at least half the end face. In addition, the shield preferably completely covers the end faces of the device component.

If the end faces of the device component are not flat but curved, for example, then, according to an alternative embodiment, the outer antenna sections are shaped according to the surface, ie also curved, for example. Consequently, the antenna is arranged on the device component in a particularly space-saving manner.

The shielding prevents the magnetic field lines from spreading from the side of the outer antenna elements facing the device component to the device component. In this case, eddy current losses are at most and only slightly caused by an operational magnetic alternating field in the shielding. As a result, eddy current losses and heating in the device component caused by them are particularly advantageously avoided, as a result of which damage to the hearing aid component is prevented and its service life is increased. If the device component is made of a material with a comparatively high electrical conductivity, for example copper, or is surrounded by this material, the magnetic field generated by the antenna is due to a current induced according to Lentz's law in the surface of the device component and a pushed out of this surface by the associated opposing magnetic field, so that no shielding is required between the antenna base body and the device component.

In addition, for example, the device component is at least partially surrounded by a collar-like shield. In other words, the jacket shield has an extension in the longitudinal direction which is at most equal to the extension of the peripheral area of the device component. In this case, the jacket shield is arranged in particular in the middle between the outer antenna sections and is not necessarily (electrically) closed. The sheath shield is preferably part of the shield, but not necessarily (galvanically) connected to it. Penetration of the magnetic field lines into the device components is avoided due to the jacket shield, so that eddy current losses are at most and only slightly caused in the jacket shield.

Fig. 1

schematisch zwei als Hörhilfegeräte ausgebildete Geräte mit jeweils einer Antenne, welche einen Energiespeicher umgreift, wobei die beiden Hörhilfegeräte mit einem relativ zu diesen drehbaren Zubehörteil induktiv gekoppelt sind,

Fig. 2a

in einer perspektivischen Ansicht die U-förmige Antenne, welche den Energiespeicher umgreift, wobei äußere Antennenabschnitte eines Antennengrundkörpers der Antenne an Stirnflächen des Energiespeichers angeordnet sind und ein mittlerer Spulenkernabschnitt des Antennengrundkörpers der Antenne eine Mantelfläche des Energiespeichers teilweise abdeckt, und wobei zwischen dem Antennengrundkörper und dem Energiespeicher eine Abschirmung angeordnet ist,

Fig. 2b

in einer Seitenansicht die U-förmige Antenne gemäß der Fig. 2a,

Fig. 2c

in einer Draufsicht die den Energiespeicher umgreifende Antenne gemäß der Fig. 2a,

Fig. 3a

in einer Draufsicht auf den äußeren Antennenabschnitt eine erste alternative Ausgestaltung dessen kreissegmentartig Flanschbereiches, wobei der Flansch kleiner als die Abschirm ist,

Fig. 3b

eine zweite Alternative des äußeren Antennenabschnitts, wobei dessen Flanschbereich kreissegmentartig mit einem vergleichsweise großen Mittelpunktswinkel ausgeführt ist,

Fig. 3c

eine dritte Alternative des äußeren Antennenabschnitts, wobei dessen Flanschbereich kreissegmentartig mit einem kleinen großen Mittelpunktswinkel ausgeführt ist,

Fig. 4

schematisch einen Querschnitt einer Leiterplatte, in welche der Antennengrundkörper sowie die Abschirmung integriert sind, wobei die erste Spule mittels Leiterbahnen gebildet sind, welche in an gegenüberliegenden Breitseiten des Antennengrundkörper angeordneten Wicklungsschichten eingebracht sind,

Fig. 5a

die Leiterplatte mit integrierte Antennengrundkörper und integrierter Abschirmung im planen Zustand im Zuge der Montage der Antenne vor einer Faltung um den Energiespeicher

Fig. 5b

die Leiterplatte gemäß der Fig. 5a, wobei ein Substrat sowie eine Lackschicht der Leiterplatte nicht dargestellt sind,

Fig. 6

in einer Explosionsdarstellung die Antenne, wobei eine dritte Spule konzentrisch um die erste Spule angeordnet ist, und wobei ein Substrat sowie eine Lackschicht der Leiterplatte nicht dargestellt sind, und

Fig. 7a,b

in einer Seitenansicht die U-förmige Antenne, wobei eine räumliche Orientierung eines bei Betrieb der Antenne erzeugten magnetischen Dipolmoments eingestellt wird.

Exemplary embodiments of the invention are explained in more detail below with reference to a drawing. Show in it:

1

schematically two devices designed as hearing aids, each with an antenna, which surrounds an energy store, the two Hearing aids are inductively coupled to an accessory that can be rotated relative to them,

Figure 2a

in a perspective view the U-shaped antenna, which surrounds the energy store, with outer antenna sections of an antenna base body of the antenna being arranged on end faces of the energy store and a middle coil core section of the antenna base body of the antenna partially covering a lateral surface of the energy store, and with between the antenna base body and the Energy store a shield is arranged,

Figure 2b

in a side view the U-shaped antenna according to FIG Figure 2a ,

Figure 2c

in a top view, the antenna enclosing the energy store according to FIG Figure 2a ,

Figure 3a

in a plan view of the outer antenna section, a first alternative embodiment of its circular segment-like flange area, with the flange being smaller than the shield,

Figure 3b

a second alternative for the outer antenna section, the flange area of which is designed in the manner of a segment of a circle with a comparatively large center angle,

3c

a third alternative for the outer antenna section, the flange area of which is designed in the manner of a segment of a circle with a small, large central angle,

4

a schematic cross-section of a printed circuit board, in which the antenna base body and the shielding are integrated, the first coil being formed by means of conductor tracks which are introduced into winding layers arranged on opposite broad sides of the antenna base body,

Figure 5a

the printed circuit board with integrated antenna body and integrated shielding in the flat state during assembly of the antenna before folding around the energy storage device

Figure 5b

the circuit board according to the Figure 5a , whereby a substrate and a lacquer layer of the printed circuit board are not shown,

6

the antenna in an exploded view, with a third coil being arranged concentrically around the first coil, and with a substrate and a lacquer layer of the printed circuit board not being shown, and

Fig. 7a,b

in a side view, the U-shaped antenna, wherein a spatial orientation of a magnetic dipole moment generated during operation of the antenna is set.

Corresponding parts are provided with the same reference symbols in all figures.

In 1 two devices 2 are shown, which are designed as identical hearing aid devices 2a of a (binaural) hearing aid system 4 . The two hearing aid devices 2a are provided and set up to be worn behind one ear of a user (wearer, person). In other words, these are behind-the-ear hearing aids (BTE hearing aids), which have a sound tube (not shown) that is inserted into the user's ear. The respective hearing aid device 2a comprises a housing 6 made of plastic, for example. A microphone 8 with two electromechanical sound transducers 10 is arranged inside the housing 6 . The two sound converters 10 make it possible to change a directional characteristic of the microphone 8 by changing a time offset of electrical signals which are generated from recorded sound signals by means of the respective sound converter 10 . The two electromechanical sound transducers 10 are coupled in terms of signals to a signal processing unit 12 which includes an amplifier circuit. The signal processing unit 12 has electrical and/or electronic (active and/or passive) components and circuit elements.

Furthermore, a loudspeaker 14 is coupled to the signal processing unit 12 in terms of signal technology, by means of which the electrical signals of the sound transducer 10 processed by the signal processing unit 12 are output again as sound signals. These sound signals are conducted into the ear of a user of the hearing aid system 2 by means of the sound tube, which is not shown in detail.

The power supply (voltage and current supply) of the signal processing unit 12, the microphone 8 and the loudspeaker 14 of each hearing aid device 2a takes place by means of a rechargeable energy store 16 (shown in dashed lines). Each of the hearing aid devices 2a also has an antenna 18, by means of which an inductive transmission of information 20 is made possible between the two hearing aid devices 2a. The antenna 18 partially surrounds the energy store 16 . The inductive transmission of information 20 between the two hearing aid devices 2a is used to exchange data. Due to the exchange of data, improved directional microphony (beamforming) is made possible, for example.

In the execution of 1 accessory 22 is also shown, which is, for example, a remote control or a relay station, which is carried, for example, by the user. This accessory part 22 has a receiver 23, with which a further inductive information transmission 20, indicated by the dash-dotted arrows, is realized with the two antennas 18 of the two hearing aid devices 2a. The inductive information transmission 20 is used to exchange data between the additional device 22 and the hearing aids 2a.

In addition, the antenna 18 is used for inductive and wireless energy transmission from a charging device, not shown, to the hearing aid device 2a, so that in a specific operating mode the rechargeable energy store 16 of the hearing aid device 2a can be charged by means of the antenna 18. In other words, energy is transmitted inductively by means of the antenna 18 and is used to charge the energy store 16 .

In configurations that are not shown, the devices 2 are a sensor (sensor system) such as a blood pressure, blood sugar or heart rate monitor or a computer system worn on the body (wearable computer, wearables) or a component of a sensor or actuator system worn on the body ( body area network). In any case, these devices 2 have an antenna 18 for the inductive transmission of information and possibly for the inductive transmission of energy.

the Figures 2a to 2c show the antenna 18 of the device 2. The antenna 18 has a foil-like antenna base body 24 formed from a soft magnetic ferrite. The antenna base body 24 includes a central coil core section 26 which carries a first coil 28 . The middle coil core section 26, and thus a coil axis of the first coil 28, extends along a longitudinal direction L. An outer antenna section 30 is arranged on its end faces with respect to the longitudinal direction L, forming a U-shape of the antenna base body 24. Thus, the two outer antenna sections 30 are oriented perpendicular to the longitudinal direction L. The two outer antenna sections 30 extend in a transverse direction Q oriented perpendicular to the longitudinal direction L.

The two outer antenna sections 30 of the antenna base body 24 each have a coil core area 32 at the edge, which adjoins the central coil core section 26 . The edge-side coil core sections 32 each carry a second coil 34, the coil axis of which is oriented in the transverse direction Q. Furthermore, the two outer antenna sections 30 each have a flat flange section 36 which borders on the free end side, ie on the end face of the peripheral coil core section 32 opposite and facing away from the central coil core section 26 . The outer antenna section 30 extends semicircularly from the free-end side of the corresponding coil core section 32 at the edge, with the coil core section 32 at the edge and the flange section 36 extending in a common plane oriented perpendicularly to the longitudinal direction L. The two outer antenna sections 30 are structurally identical and mirror-symmetrical to one another, with their plane of symmetry running perpendicular to the longitudinal direction L.

In an alternative that is not shown in any more detail, the two outer antenna sections 30 are not constructed in the same way or are symmetrical. For example, the flange sections 36 are adapted to a shape of the device component 16 or the flange sections have, for example, a recess for contacting the device component 16 .

The first coil 28 and the two second coils 34 are in each case electrically contacted with electronics (not shown) or alternatively with a power source (not shown). At most, the first coil 28 and the two second coils 34 can be switched independently of one another, ie can be acted upon (controlled) with a specified current intensity.

A device component 38 of the device 2 is arranged in an interior area I, between the outer antenna sections 30 , which is the energy store 16 of the device 2 embodied as a battery. The energy store 16 has a shape that corresponds to two coaxially mounted cylinders arranged one on top of the other, the cylinder axes of which extend in the longitudinal direction L. The opposite and spaced flat surfaces of the cylinders form parallel end faces 40 of the energy store 16. The lateral surfaces of the two cylinders form a peripheral region 42 of the energy store 16. The end faces 40 of the extend in a plane perpendicular to the longitudinal direction L, so that they are parallel to the outer antenna sections 30 are oriented. In summary, the outer antenna sections 30 are arranged on opposite end faces 40 of the energy store and the middle coil core section 26 overlaps the peripheral area 42 of the device component 38 designed as the energy store 16.

A film-like shielding 44 is arranged between the antenna base body 24 , that is to say the middle coil core section 26 and the outer antenna section 30 , and the device component 38 . The shielding 44 is therefore arranged on the side of the two outer antenna sections 30 facing the middle coil core section 26 and on the side of the middle coil core section 26 facing the outer antenna sections 30 . The area of the shielding 44 arranged on the middle coil core section 26 or the area which is arranged between the middle coil core section 26 and the energy store 16 is referred to below as the middle shielding section 46 . Correspondingly, the two areas of the shield 44 which are arranged on the outer antenna sections 30 are referred to as outer shield sections 48 . The foil-like shield 44 has a conductivity of more than 10 ⁶ S/m and is formed from or comprises diamagnetic material. According to the embodiment of 2 the shield 44 is formed by a copper foil.

The shielding 44 is larger than the antenna base body 24 and covers it. Thus, the middle shielding section 46 has an extent in a plane parallel to the middle coil core section 26, which is greater than the extent of the coil core section 26. Similarly, the outer shielding sections 48 have an extent in a plane parallel to the outer antenna sections 30, which is larger than the expansion of the outer antenna sections 30. The two outer shielding sections 48 cover the end faces 40 (end faces) of the energy store 16 completely.

Because of the shielding, a propagation of a magnetic field into the interior area I is prevented or at least reduced. Because of this, no or at least correspondingly fewer eddy currents are induced in the energy storage device 16 arranged in the interior area I, so that it is not heated up or damaged.

Arranging the antenna 18 directly on the energy store 16 or on the device component 38 and arranging the shielding 44 between the antenna base body of the antenna element 18 and the energy store 16 results in a space-saving arrangement of the antenna 18 in the device 2 . As a result, the device 2 is designed to be particularly space-saving (small).

the Figures 3a to 3c each show an alternative embodiment of the flange sections 36. In the case of FIG Figure 3a The first alternative shown, the flange section 36 shaped as a circular segment is reduced compared to the shield 44 . The extension of the circular segment along its radial direction is smaller than the extension of the shield 44 in this direction. In this way, an expansion of magnetic field lines into the inner area I is further reduced. The second alternative according to the Figure 3b and the third alternative of 3c point different central angles of the flange section 36 shaped as a circular segment. The flange section 36 of the Figure 3b has a central angle of 120 °, the flange portion 36 of 3c has a central angle of 60°. By varying the flange sections 36, an antenna surface is adapted to operational requirements.

4 shows a flexible printed circuit board 50 in which the shielding 44 and the antenna base body 24 are integrated. The antenna base body 24 formed from a ferrite is laminated into the printed circuit board 50 . A first winding layer 52 and a second winding layer 54 are arranged on opposite broad sides of the antenna base body 24 . The first winding layer 52 and the second winding layer 54 each have conductor tracks 56 ( Figure 5a ), by means of which the turns of the first coil 28 and the turns of the two second coils 34 are formed. The conductor tracks 56 are introduced into the first winding layer 52 and into the second winding layer 54 in the course of the production of the printed circuit board 50 by means of etching. The conductor tracks 56 are electrically connected to one another by means of vias 58 . Furthermore, the first winding layer 52 is arranged or applied on a substrate 60 . The shielding 44 is arranged on the side of the substrate 60 opposite the first winding layer 52 and is formed here by means of a copper layer of the printed circuit board 50 . In this case, the shielding 44 is arranged on the broad side of the substrate 60 facing the inner region I. Furthermore, a lacquer layer 62 is arranged on the broad side of the shielding 44 facing the inner area I and on the broad side of the second winding layer 54 facing away from the inner area I, ie facing an outer area A.

the Figures 5a and 5b show the antenna 18 in the flat state. In the course of mounting the antenna 18 in the device 2, the antenna 18 is folded (bent) so that the antenna 18 encompasses the energy store 16 in a space-saving manner. This is made possible due to the use of the flexible printed circuit board 50 and due to the foil-like and foldable design of the antenna base body 24 . The antenna base body 24 and the shielding 44 are in accordance with the embodiment the 4 integrated into the circuit board 50. the Figure 5a shows the flexible circuit board 50 with integrated shielding 44 and integrated antenna body 24, in which Figure 5a This printed circuit board 50 is shown without the substrate 60 and without the two layers of lacquer 62 for the purpose of improved visibility of the antenna base body 24 and the shielding 44 .

the 6 shows the antenna 18 in an exploded view Figure 5b the substrate 60 and the two lacquer layers 62 of the printed circuit board 50, in which the antenna base body 24 and the shielding 44 are integrated, are not shown for the purpose of improved visibility of individual components of the antenna 18. The antenna 18 has a third coil 64 which is arranged concentrically to the first coil 28 around the central coil core section 26 . This third coil 64 is formed from conductor tracks 56 which are electrically connected by means of vias 68 and which are introduced into a third winding layer 66 and into a fourth winding layer 68 in particular by means of etching. The third winding layer 66 or the conductor tracks 56 of the third winding layer 66 is arranged on the side of the first winding layer 52 facing the inner area I and the fourth winding layer 68 is arranged on the side of the second winding layer 54 facing the outer area A.

Furthermore, it can be seen that with respect to the longitudinal direction L, adjacent vias 58 are arranged offset to one another in a direction perpendicular to the longitudinal direction L and perpendicular to the transverse direction Q. In other words, adjacent vias 58 are not arranged in a common plane, which is defined by the longitudinal direction L and the transverse direction Q. The vias 58 require more space in the longitudinal direction L than the conductor tracks 56. Due to manufacturing or production, there is a minimum distance between two conductor elements, in other words between two adjacent conductor tracks 56, between two adjacent vias 58 and between a conductor track 56 and that via 58 which is connected to one of the conductor tracks 56 adjacent to this conductor track 56 is necessary. If the vias 58 are not staggered, they will be spatially closest to one another arranged conductor elements two adjacent vias 58. As a result of the compared to the conductor tracks 56 larger space requirement of the vias 58 in the longitudinal direction L, a distance between two adjacent conductor tracks 56 is greater than the minimum distance. In the case of a staggered arrangement of the vias 58, on the other hand, the smallest distance between two conductor elements is between a conductor track 56 and the via 58 connected to the directly adjacent conductor track 56. Due to the smaller space requirement in the longitudinal direction L of the conductor tracks 56 compared to the via 58, with a staggered arrangement of directly adjacent vias 58, the distance between directly adjacent conductor tracks 56 is smaller, so that a winding density of the corresponding coil is increased.

the Figures 7a and 7b show representatively a method of operating the antenna 18, which according to the 2 is trained. In the Figure 7a a first mode of operation of antenna 18 is shown, with first coil 28 and the two second coils 34 being switched simultaneously, and with the current direction being selected such that the magnetic fields generated by coils 28 and 34 are constructively superimposed. So the current flows through the coils 28 and 34 in the same sense. The antenna 18 acts in the manner of a ferrite rod antenna with a comparatively large end face, with a magnetic dipole moment m generated during operation being oriented essentially perpendicular to the outer antenna sections 30 and parallel to the longitudinal direction L.

Figure 7b shows the antenna 18 in a second operating mode, with only one of the two second coils 34 being connected. The magnetic dipole moment m generated during operation is not perpendicular to the outer antenna sections 30, but tilted at an angle α to the normal N of the outer antenna sections 30 in a plane which is spanned by the longitudinal direction L and the transverse direction Q.

In the Figures 7a and 7b is next to the antenna 18 designed as a coil receiver 23 of the accessory 22 is shown, the coil axis S perpendicular to is oriented towards the outer antenna sections 30 of the antenna 18 or is rotated at the angle α relative to the normal N. An inductive coupling between the antenna 18 and the receiver 23 is at its maximum when the magnetic dipole moment m is oriented parallel to the coil axis S. By activating, in particular by energizing, one of the second coils 34, both second coils 34 and/or the first coil 28, the orientation of the magnetic dipole moment m is adjusted in such a way that it runs as parallel to the coil axis S as possible.

In summary, a spatial transmission direction, in other words the spatial orientation of the magnetic dipole moment m generated during operation of the antenna 18, is not fixed (rigid) with respect to the antenna 18, but is oriented spatially differently depending on the switching of the coils 28,34. In this way, the magnetic dipole moment m generated during operation of the antenna 18 is set in accordance with an orientation of a receiver 23 relative to the antenna 18 by means of a circuit of one of the coils 28 , 34 . Consequently, a reliable inductive coupling of the antenna 18 to the receiver 23 is made possible even when the receiver 23 is rotated relative to the antenna 18 and thus a reliable inductive transmission of information is realized.

The invention is not limited to the exemplary embodiments described above. On the contrary, other variants of the invention can also be derived from this by a person skilled in the art without departing from the subject matter of the invention.

Reference List

2

device

2a

hearing aid device

4

hearing aid system

6

Housing

8th

microphone

10

sound transducer

12

signal processing unit

14

speaker

16

energy storage

18

antenna

20

inductive information transfer

22

accessory

23

recipient

24

antenna body

26

middle coil core section

28

first coil

30

outer antenna section

32

peripheral coil core area

34

second coil

36

flange section

38

device component

40

face

42

perimeter

44

shielding

46

middle shield section

48

outer shield section

50

circuit board

52

first winding layer

54

second winding layer

56

trace

58

via

60

substrate

62

paint layer

64

third coil

66

third winding layer

68

fourth winding layer

a

angle

A

outdoor area

I

interior

L

longitudinal direction

m

magnetic dipole moment

N

Normal of the outer antenna sections

Q

transverse direction

S

coil axis

Claims (10)

1. Antenna (18), in particular of a hearing aid, for inductive information and/or energy transmission, said antenna comprising

   a foil-like antenna base body (24) with a central coil core section (26) carrying a first coil (28), and with outer antenna sections (30) disposed opposite each other on both sides of the central coil core section (26),
   characterized in

   that the outer antenna sections (30) each have an edge-side coil core section (32) adjacent to the central coil core section (26), the edge-side coil core sections (32) each carrying a second coil (34), and the broad sides of the outer antenna sections (30) being angled perpendicularly with respect to the central coil core section (26) to form a U-shape.
2. Antenna (18) according to claim 1,
   characterized in
   that each of the outer antenna sections (30) has a flange section (36), in particular in the form of a circular segment, which adjoins the end face of the edge-side coil core section (32), which faces away from the central coil core section (26).
3. Antenna (18) according to claim 1 or 2,
   characterized by
   a foil-like shielding (44), which is arranged respectively on the side of the two outer antenna sections (30) facing the central coil core section (26) and on the side of the central coil core section (26) facing the outer antenna sections (30).
4. Antenna (18) according to claim 3,
   characterized in
   that the shielding (44) is larger than or equal to the antenna base body (24) and covers it.
5. Antenna (18) according to one of claims 1 to 4,
   characterized in

   - that the antenna base body (24) or the shielding (44) and the antenna base body (24) are integrated in a printed circuit board (50), in particular a flexible printed circuit board,

   - that a first winding layer (52) and a second winding layer (54) are arranged on opposite broad sides of the antenna base body (24), and

   - that the first winding layer (52) and the second winding layer (54) each have conductor paths (56) by means of which the windings of the first coil (28) and the windings of the second coil (34) are formed.
6. Antenna (18) according to claim 5,
   characterized by
   a third winding layer (66) and a fourth winding layer (68), which are arranged on the broad side of the first winding layer (52) facing away from the antenna base body (24) or respectively on the broad side of the second winding layer (54) facing away from the antenna base body (24), a third coil (64) being formed by means of conductor paths (56) of the third winding layer (66) and by means of conductor paths (56) of the fourth winding layer (68), which third coil is arranged concentrically with respect to the first coil (28) or with respect to one of the second coils (34).
7. Method for operating an antenna (18) according to one of claims 1 to 6, wherein a spatial orientation of a magnetic dipole moment (m) generated during operation is set by activating, in particular by energizing, one of the second coils (34), both second coils (34) and/or the first coil (28) according to an orientation of a receiver (23) relative to the antenna (18).
8. Device (2), in particular hearing device, preferably hearing aid, with an antenna (18) according to one of claims 1 to 6.
9. Device (2) according to claim 8,
   characterized by
   a device component (38), in particular an energy storage device, wherein the antenna (18) surrounds the device component (38) at least in sections.
10. Device (2) according to claim 8 or 9,

    - wherein the outer antenna sections (30) are disposed on opposite end faces (40) of the device component (38), and

    - wherein the central coil core section (26) overlaps a peripheral region (42) of the device component (38).

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