Patent Grant
8130990
This application claims priority of German application No. 10 2007 046 437.3 filed Sep. 28, 2007, which is incorporated by reference herein in its entirety.
The invention relates to a hearing aid system comprising a first and a second hearing aid which may be worn respectively in or on an ear of a user, which respectively comprise an input transducer for receiving an input signal and converting into an electrical input signal, a signal processing unit for processing and amplifying the electrical input signal and emitting an electrical output signal, an output transducer for converting the electrical output signal into an output signal which may be perceived by the user as an acoustic signal and means for wireless signal transmission between the hearing aids.
The invention further relates to a method for operating such a hearing aid system.
Hearing aids generally have a manually actuatable switch for switching on and off. In some hearing aids, this switch is incorporated in the battery compartment, so that the hearing aid is switched off as soon as the user pivots the battery compartment slightly out of the normal operating position.
As a result of desired miniaturization, in modern hearing aids there is only relatively little space available for attaching operating elements. Switching on and off such a hearing aid, therefore, requires a certain degree of motor control. Moreover, it is not uncommon for a user to forget to switch off his or her hearing aid, after having removed it from the head for storage.
A hearing aid system comprising two hearing aids which may be worn on the head, between which a wireless signal transmission is provided, for example for transmitting control signals, is known from EP 0 941 014 A2.
Acoustic systems and, in particular, hearing aids which automatically switch between different processing programs are known from DE 10 2004 056 733 A1. In this case it is provided that the signal processing device of a relevant acoustic system has a high frequency detector (HFD) for analyzing an input signal, the output signal thereof being able to be used by the signal processing unit for processing one or more input signals. As a result, the presence of an active mobile phone which emits electromagnetic radiation in the high frequency range may be specifically determined. Consequently, it may be switched to telephone mode with a high degree of reliability, depending on the situation.
A hearing aid is disclosed in the publication DE 31 09 049 C2, in which by the detection of a magnetic field the operating switch of the hearing aid may be switched on or off.
It is the object of the present invention to implement automatic switching on and/or off in a hearing aid system comprising two hearing aids which may be worn on the head.
This object is achieved by a hearing aid system and by a method as claimed in the independent claims.
In a hearing aid of a hearing aid system according to the invention, an input signal is received by means of an input transducer and transferred into an electrical input signal. At least one microphone generally serves as an input transducer, which picks up an acoustic input signal and converts said input signal into an electrical input signal. Modern hearing aids frequently comprise a microphone system comprising a plurality of microphones, in order to achieve a reception which is dependent on the direction of incidence of acoustic signals, a directional characteristic. However, telephone coils or antennae are also common as input transducers for the reception of wirelessly transmitted input signals and conversion into electrical input signals. The input signals converted by the input transducer into electrical input signals are fed to a signal processing unit for further processing and amplification. The further processing and amplification takes place to compensate for the individual hearing loss of a user, generally depending on the signal frequency of the input signal. The signal processing unit delivers at its output an electrical output signal, which is fed via an output transducer to the ear of the hearing aid wearer, so that said hearing aid wearer perceives the output signal as an acoustic signal. Earpieces which generate an acoustic output signal are conventionally used as output transducers. However, output transducers are also known for generating mechanical oscillations, which directly excite specific parts of the ear into oscillation, such as for example the small bones in the ear. Moreover, output transducers are known which directly stimulate nerve cells of the ear. Moreover, operating elements (on/off switches, program switches, volume adjusters etc.) may also be present.
Moreover, a hearing aid of a hearing aid system according to the invention comprises means for wireless signal transmission between the hearing aids, for example implemented by a signal transmission and control unit in combination with a transmitting and receiving coil, which are respectively present in both hearing aids.
For the power supply, hearing aids comprise a battery or a rechargeable battery. In order to increase the life of the power source, consideration is given to low energy consumption of all components of the device.
Therefore, the transmit power in a hearing aid system which provides wireless signal transmission between the hearing aid devices, is adjusted such that precisely the distance between the two ears of a user may be bridged thereby.
The invention provides, at least in one of the two hearing aids, to determine the field strength of a received signal transmitted by the other hearing aid, from which an indication about the current distance between the two hearing aids relative to one another may be obtained. If both hearing aids are worn at the same time on the head, therefore, the field strength is adjusted such that reliable data transmission between the hearing aids is just possible. If the hearing aids, however, are located in the vicinity of one another in a storage box, the field strength measured in the hearing aid is many times higher. From the measured field strength, a hearing aid may therefore derive information about whether it is worn on the head or whether it is located in the storage box.
For the method according to the invention, a relatively approximate determination of the field strength is sufficient. The field strength measurement may, for example, be carried out by using a simple useful signal level measuring device, which is incorporated in one of the receiving filter stages or receiving amplifier stages of the signal transmission unit and detects a voltage value.
Advantageously, the measured field strength is compared with a threshold value. If the field strength is below the threshold value, this is an indication that the two hearing aids are worn on the head. If the measured field strength, however, exceeds the threshold value, this is an indication that the hearing aids are not worn on the head, but are located in the close vicinity of one another for storage, for example in a storage box.
As soon as the measured field strength exceeds the threshold value, the relevant hearing aid is automatically switched off, for example by means of a suitable software control. In the switched-off state, essential power consumers of the hearing aid, such as for example the input transducer, the output transducer as well as the signal processing processor, are disconnected from the power supply. The hearing aid according to the invention, however, is not completely disconnected from the power source, so that at least components for the wireless signal transmission between the hearing aids are still active. Nevertheless, the power consumption is reduced in this switched-off state (sleep mode) in comparison with the fully switched-on hearing aid. In sleep mode, the relevant hearing aid recognizes when the measured field strength falls below the threshold value, whereby the hearing aid automatically switches itself on again.
The invention provides the advantage that, in a simple manner, the relevant hearing aid is therefore automatically switched on and off. Thus also a manually actuatable operating element for switching on and off may be entirely dispensed with. This is in particular also advantageous for the manufacture of a waterproof hearing aid.
Advantageously, both hearing aids of the hearing aid system according to the invention have a corresponding field strength measuring device. However, it is also possible that only one of the two hearing aids has a field strength measuring device and a control signal is transmitted from this hearing aid to the other hearing aid, which then causes the second hearing aid to be automatically switched on or off.
Naturally, it is possible within the scope of the invention not to measure directly the field strength, at which a signal transmitted by the second hearing aid of a hearing aid system according to the invention is applied to the first hearing aid, but also any other variable dependent on this field strength. For example, the signal level of the signal received by the first hearing aid may be determined.
The invention is described in more detail hereinafter with reference to an embodiment, in which:
Moreover, in the hearing aids 1 and 11 the one respective field strength measuring device 6 and/or 16 is present, by means of which the field strength of an electromagnetic signal received by the transmitting and receiving coil 7 and/or 17 and emitted by the transmitting and receiving coil of the respective other hearing aid may be measured. For the decision whether the two hearing aids are currently worn on the head or are stored in the vicinity of one another, a relatively approximate determination of the field strength is sufficient. Preferably, for the field strength measurement a level meter is incorporated in one of the receiving filter stages or receiving amplifier stages arranged downstream of the transmitting and receiving coil 7 and/or 17. Advantageously, the measured signal levels are compared in the signal transmission and control units 5 and/or 15 with a specific threshold value. If the measured field strength exceeds the threshold value, this is an indication that the two hearing aids 1 and/ 11 are at a very short distance from one another. The hearing aids 1 and 11 are therefore, controlled by the signal transmission and control units 5 and/or 15, switched into sleep mode and remain in this state until the measured field strengths fall below the threshold value again. In sleep mode the hearing aid is switched off, i.e. essential components of the hearing aid such as the microphones 2 and/or 12, the signal processing units 3 and/or 13 and the earpieces 4 and/or 14 are disconnected from the power source 8 and/or 18. Only the components required for wireless signal transmission, namely the transmitting and receiving coils 7 and/or 17, the field strength measuring devices 6 and/or 16 as well as the signal transmission and control units 5 and/or 15 are still in operation and thus connected to the power sources 8 and/or 18. In order to reduce power consumption further, in sleep mode the signal transmission does not take place continuously between the hearing aids but only at specific times, for example in the form of short pulses, which are periodically repeated in the range of seconds. So that this signal transmission, which is carried out only at specific times, functions, a synchronization of the hearing aids 1 and/or 11 is required. Advantageously, both hearing aids 1 and 11 are quartz-controlled, so that a relatively good synchronization of the two hearing aids 1 and 11 is provided in any case. Also, the signals transmitted between the hearing aids may be used for synchronization and, in particular, for fine adjustment during synchronization.
The invention provides the advantage that in the hearing aids 1 and 11, which are provided for wireless signal transmission, an automatic switching on and off of the hearing aids is implemented at relatively low additional cost. Also corresponding operating elements for manually switching the hearing aids on and off may therefore be dispensed with. This permits further miniaturization of the devices and increases the operating comfort. Moreover the absence of the operating elements means that production of a waterproof hearing aid is facilitated.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2007 046 437 | Sep 2007 | DE | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4467145 | Borstel | Aug 1984 | A |
| 20040052391 | Bren et al. | Mar 2004 | A1 |
| 20040208332 | Baechler | Oct 2004 | A1 |
| 20060109994 | Husung et al. | May 2006 | A1 |
| 20070253584 | Rass | Nov 2007 | A1 |
| Number | Date | Country |
|---|---|---|
| 3109049 | Sep 1982 | DE |
| 102004056733 | Jun 2006 | DE |
| Number | Date | Country | |
|---|---|---|---|
| 20090087005 A1 | Apr 2009 | US |
