JP3890767B2 - External sound processing device for ear wearing such as hearing aids - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce disturbance due to leakage of an external sound to ears by outputting the external sound that is digitally processed or whose speech speed is converted to a receiver through a filter and suppressing electrically or physically the external sound that is leaked into an external auditory miatus. SOLUTION: An amplifier 10 amplifies an analog signal picked up by a microphone 2 to a proper level. A DSP signal processing section 13 detects a voice pitch waveform and a repetitive waveform to insert the waveform to the original signal so as to conduct only speech speed conversion. On the other hand, a phase control section 17 generates a sound whose phase is inverted to a phase of an external sound as a suppressing sound, and a gain control section 18 controls the level of the suppressing sound. An adder 19 sums outputs from a filter 15 and the gain control section 18 analogically and outputs the sum to a driver 16. Thus, an external leakage sound leaked into an external auditory miatus is acoustically cancelled by the suppressing sound component contained in an output from a receiver 4.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ear-mounted external sound processing device such as a hearing aid, and more particularly to a device that is less disturbed by external leak sound.
[0002]
[Prior art]
Hearing aids are typical devices that are attached to the ear canal to process external sounds in an analog or digital manner. In addition, the hearing aid simply has the function of amplifying and phase processing the external sound and outputting it from the receiver to the ear canal. In addition to this, the external sound (sound) received by the microphone is digitized. A speech rate conversion hearing aid that performs speech rate conversion processing has been proposed. Normally, this speech rate conversion hearing aid is designed to make it easier for the hearing aid wearer to understand what the speaker has spoken by slowing down the speech rate of external speech without changing the speech pitch. is there.
[0003]
[Problems to be solved by the invention]
However, in hearing aids with built-in speech rate conversion hearing aids or filters that greatly change the sound quality of external sounds, the sound leaking from the gap between the hearing aids and the external auditory canal causes confusion in the recognition of external sounds. There is an inconvenience. This tendency is especially strong when the degree of hearing loss is not so bad, or when the hearing aid does not fit the ear structurally or in shape, and a hearing aid with a shape that fits your ear is made to order. In some cases, the cost was high.
[0004]
An object of the present invention is to provide an external sound processing apparatus for ear wearing such as a hearing aid that is less disturbed by external sound leakage.
[0005]
[Means for Solving the Problems]
(1) The invention of claim 1
A digital processing unit that digitally processes the external sound and outputs it to the receiver;
Leak sound suppression means for suppressing the sound that the external sound leaks into the ear canal;
Instruction means for instructing the start of the sealing degree evaluation;
A sealing degree evaluation means for evaluating the sealing degree between the apparatus main body and the ear canal when receiving an instruction from the instruction means;
The leak sound suppression means performs suppression control of sound that leaks according to the evaluated degree of sealing .
[0006]
In the digital processing unit, the external sound is output to the receiver through a filter, or the speech speed conversion process is performed and output to the receiver. At the same time, the leak sound suppression means electrically or physically suppresses the external sound leak into the ear canal. Suppression of the leak sound increases the dB ratio between the output from the receiver and the external sound leak, and the sound that can be recognized by the wearer of the apparatus is only the external sound output from the receiver.
In addition, the degree of sealing between the apparatus main body and the external auditory canal becomes poor when the shape of the apparatus itself does not match the shape of the external auditory canal or when the apparatus main body is not properly attached to the external auditory canal. The evaluation of the sealing degree is performed by using a test sound source, and leakage noise suppression control is performed according to the evaluated sealing degree. Accordingly, the degree of suppression is increased as the sealing degree is worse.
[0009]
(2) The invention of claim 2
The sealing degree evaluation means includes
A test sound source device that generates a constant sound and outputs it to the outside;
An ear canal microphone that detects sound in the ear canal;
Means for stopping the operation of the digital processing unit and evaluating the sealing degree based on the detection sound of the ear canal microphone.
[0010]
When evaluating the degree of sealing, a certain sound is generated by the test sound source device and output to the outside, and this externally output sound is picked up by the ear canal microphone. At this time, the sound picked up by the ear canal microphone is a sound leaking into the ear canal. The sealing degree evaluation means evaluates the sealing degree based on the detection sound of the ear canal microphone at this time. At this time, the operation of the digital processing unit needs to be stopped. Therefore, if the detected sound of the ear canal microphone is large, it is evaluated that the sealing degree is poor.
[0011]
(3) The invention of claim 3
The leak sound suppression means includes a suppression sound generation unit that generates an electroacoustic suppression sound and outputs the generated sound to the receiver.
[0012]
The suppression of the external sound leak sound is performed by generating an electroacoustic suppression sound, that is, by generating a suppression sound by an acoustic propagation wave formed by electrical processing. The electrical processing is, for example, phase control or amplitude control. As described below, ideally, the suppression effect can be maximized by generating the same level of suppression sound in the opposite phase to the external sound leakage sound. When the sealing degree evaluation means is provided in claim 4, the sealing degree is a comprehensive value of a physical sealing state between the apparatus main body and the external auditory canal and an electroacoustic sealing degree due to the suppression sound.
[0013]
(4) The invention of claim 4
The suppression sound generation unit includes a phase control unit that generates a sound having a phase opposite to that of the external sound as a suppression sound.
[0014]
By generating a sound having a phase opposite to that of the external sound as the suppression sound, the leakage sound into the ear canal is canceled in phase, so that it is possible to substantially suppress the leakage sound into the ear canal.
[0015]
(5) The invention of claim 5
The suppression sound generation unit may further include a gain adjustment unit that adjusts the gain of the external sound.
[0016]
The suppression sound for suppressing the sound leaking into the ear canal is most preferably to generate a sound having the same amplitude as that of the leaking sound. Therefore, in the present invention, it is possible to generate a suppression sound having the same amplitude as that of the leak sound in the ear canal by adjusting the gain of the external sound.
[0017]
(6) The invention of claim 6
The digital processing unit and the suppression sound generation unit share an input microphone and a receiver.
[0018]
By using a common input microphone and receiver for the digital processing unit and the suppression sound generation unit, the structure of the entire apparatus can be simplified.
[0019]
(7) The invention of claim 7
The leak sound suppression means includes an ear canal contact portion whose outer periphery can swell, and an adjustment portion that adjusts the degree of bulge of the ear canal contact portion.
[0020]
In the present invention, the external sound leakage sound into the ear canal is physically suppressed. In other words, the outer ear canal contact portion provided in the apparatus has a structure in which the outer periphery can swell, and the degree of this bulge is adjusted by the adjusting portion. For this reason, it is possible to fit the outer ear canal contact portion exactly to the ear canal by appropriately adjusting the adjustment portion. At this time, an appropriate fit state can be set by adjusting the degree of swelling according to the degree of sealing evaluated by the sealing degree evaluation means. The degree of swelling of the ear canal contact portion can be adjusted by injecting air or the like into the ear canal contact portion.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a diagram showing a wearing state of a speech speed conversion hearing aid that is an embodiment of the present invention. The hearing aid main body 1 includes a microphone 2 that captures external sound, a digital processing unit 3 that digitally performs processing such as amplification processing and speech speed conversion processing on the external sound captured by the microphone 2, and is digitally processed. And a receiver 4 for outputting the recorded sound into the external auditory canal 5. The external sound 6 is captured by the microphone 2 of the hearing aid main body 1, and leaks into the ear canal 5 as an external leak sound 8 from the gap 7 between the hearing aid main body 1 and the external auditory canal 5. In the hearing aid of this embodiment, this extraneous leak sound 8 is suppressed by electroacoustic processing so that the wearer can recognize only the processed sound that has substantially passed through the hearing aid body 1.
[0022]
FIG. 2 is a configuration diagram of the hearing aid.
[0023]
The digital processing unit 3 includes an amplifier 10 that amplifies the analog signal received from the microphone 2 to an appropriate level, a filter 11 that includes an anti-aliasing filter that prevents aliasing when quantizing, and an A / D conversion. A DSP signal processing unit 13 that performs signal processing with the DSP 12, a D / A converter 14 that performs D / A conversion on the result obtained by the DSP signal processing, a filter 15 including a smoothing filter, and a filter output The driver 16 amplifies to an appropriate level.
FIG. 3 is a functional block diagram of the DSP signal processing unit 13. That is, the DSP signal processing unit 13 includes a phase control unit 13a, a gain control unit 13b, and a speech rate conversion unit 13c. The speech speed conversion unit 13c detects a voice pitch waveform or a repetitive waveform from the external sound captured by the microphone 2, and inserts the waveform into a signal of one or more waveforms without changing the voice pitch. Process to slow down speaking. For pitch detection, for example, an autocorrelation method can be used, and for speech speed conversion, for example, a speech time compression / expansion method as disclosed in Japanese Patent Laid-Open No. 7-77999 can be used. The phase control unit 13a generates a sound having a phase opposite to the phase of the external sound as a suppression sound, and the gain control unit 13b controls the level of the suppression sound, that is, the gain. The adder 13d adds the output of the speech speed conversion unit 13c and the outputs controlled by the phase control unit 13a and the gain control unit 13b, and outputs the result to the D / A conversion unit 14.
[0024]
By configuring the DSP signal processing unit 13 as shown in FIG. 3, the external leak sound 8 leaking into the ear canal 5 is acoustically canceled by the suppressed sound component included in the output from the receiver 4, and the speech speed is converted. Only the sound is recognized. The phase control unit 13a performs phase control so that the suppression sound finally output from the receiver 4 is opposite in phase to the external leakage sound 8. In designing, the microphone 2, the amplifier 10, and the driver 16 The phase characteristics of the receiver 4 and the like are taken into consideration. The gain controller 13b controls the gain so that the suppression sound finally output from the receiver 4 has the same level as the external leak sound.
[0025]
FIG. 4 is a configuration diagram of a hearing aid that processes the phase control unit and the gain control unit in an analog manner.
[0026]
In the hearing aid shown in FIG. 2, the DSP signal processing unit 13 performs processing for suppressing the external sound leakage sound in addition to the speech speed conversion. However, since the distance from the microphone 2 to the receiver 4 is only a few centimeters, this distance time However, in reality, it is difficult to perform phase control and gain control during this distance time with the current performance of the DSP chip. Therefore, the hearing aid shown in FIG. 4 solves this problem by processing the phase control and gain control in an analog manner.
[0027]
In the hearing aid shown in FIG. 4, the DSP signal processing unit 13 performs only speech speed conversion. The adder 19 adds the output of the filter 15 and the output of the gain control unit 18 in an analog manner and outputs the result to the driver 16. The functions of the phase control unit 17 and the gain control unit are the same as those of 13a and 13b in FIG.
[0028]
FIG. 5 is a configuration diagram of a hearing aid according to another embodiment of the present invention.
[0029]
This hearing aid is similar to the hearing aid shown in FIG. 4, a test sound source device including a test sound source 20, a driver 21, and a receiver 22, an ear canal microphone 23 for detecting sound in the ear canal 5, and a detection signal from the microphone 23 at an appropriate level When the test mode is set, the operation of the DSP signal processing unit 13 is stopped (therefore, the speech speed conversion operation is stopped), and the test is performed. The sound source device is operated, and the sealing degree is evaluated based on the detection sound of the ear canal microphone 23 at that time (the synthesized sound of the test sound and the leak sound with phase / gain control), and the phase control unit 17 and A control unit 26 for adjusting the control amount of the gain control unit 18 is added.
[0030]
This hearing aid operates as follows.
[0031]
When the test mode is set by turning on the test switch 25, the control unit 26 drives the test sound source 20. The test switch is a button switch that is manually turned on and automatically turned off. The signal output from the test sound source 20 is amplified to an appropriate level by the driver 21 and emitted from the receiver 22 to the outside as sound. The control unit 26 simultaneously stops the operation of the DSP signal processing unit 13 so that the signal input from the microphone 2 is processed by the DSP signal processing unit 13 and is not output from the receiver 4 into the ear canal 5. Therefore, the signal of the test sound source detected by the microphone 2 passes through only the path of the phase control unit 17 and the gain control unit 18 and is emitted as sound from the receiver 4 into the ear canal 5. At the same time, since the test sound emitted from the test sound source leaks into the external auditory canal, the leak of the sound and test sound emitted through the phase control unit 17 and the gain control unit 18 in the external ear canal 5 The synthesized sound is picked up by the microphone 23 and its level is detected by the control unit 26. At this time, the control unit 26 evaluates the sealing degree based on the level of the signal detected by the microphone 23. That is, it is evaluated that the greater the level, the less sufficient the degree of sealing. Here, the degree of sealing referred to here is the degree of physical sealing between the main body of the apparatus and the ear canal, and is due to the reverse phase sound that has been emitted as a suppression sound through the phase control unit 17 and the gain control unit 18 at that time. It is the total sealing degree which added the acoustic sealing degree. In accordance with this evaluation, the control amounts of the phase control unit 17 and the gain control unit 18 are adjusted so that the level is minimized, and the values are fixed when they are minimized.
[0032]
When the test mode is completed by the above processing, the test switch 25 is turned off and the normal operation mode is entered. In the normal operation mode, the control unit 26 stops the operation of the test sound source 20 and starts the operation of the DSP signal processing unit 13. Thereby, the same operation as the hearing aid shown in FIG. 4 is performed.
[0033]
FIG. 6 is a configuration diagram of the hearing aid.
[0034]
The receiver 22, the test switch 25, and the microphone 2 are provided on the externally exposed portion of the hearing aid main body 1. The receiver 4 and the microphone 23 are provided on the ear canal side of the hearing aid body. With such an arrangement structure, in the test mode, the test sound emitted from the receiver 22 is input to the microphone 2, is subjected to phase control and gain control, and is emitted from the receiver 4 into the external ear canal 5. A synthesized sound with the sound leaking from the contact portion to the ear canal 5 into the ear canal is detected by the microphone 23. The control unit adjusts the control amounts of the phase control and the gain control so that the sound detected by the microphone 23 is minimized. Oite the normal mode, the foreign sound is detected from the microphone 2, the receiver is synthesized sound of the speech speed conversion processability sound and based on the phase-gain control amount obtained in the test mode leak sound suppressing sound 4 To the external auditory canal 5. At this time, the leak sound suppression sound cancels the external sound leak sound, so that the hearing aid wearer can recognize only the processed sound.
[0035]
FIG. 7 is a flowchart showing the operation of the control unit 26. When the test switch 25 is turned on by the hearing aid user, the operation after ST2 is performed.
[0036]
That is, the operation of the DSP signal processing unit 13 is stopped at ST2 to turn off the speech speed conversion function, and the input signal level of the microphone 23 is minimized for the operation of the test sound source and the adjustment of the phase / gain control amount at ST3, ST4, ST5. Do until it becomes. In this case, if the hearing aid main body 3 is not worn so as to fit the ear, the control unit 26 evaluates that the degree of sealing between the apparatus main body and the ear canal is poor, and increases the suppression sound for suppressing the leak sound. The control amount of the phase control and gain control is adjusted and set. When those control amounts are set in ST6, the operation of the test sound source device is turned off in ST7, the test switch 25 is automatically turned off, the operation of the DSP signal processing unit 13 is started, and the process returns to the original ST1.
[0037]
By the above operation, the control amount of the phase control unit 17 and the gain control unit 18 can be automatically set to an appropriate size by turning on the test switch 25 once when the hearing aid is worn.
[0038]
It is also possible to add an offset amount that can be manually changed to the control amount according to the degree of hearing loss. In the above embodiment, both the control amounts of the phase control unit 17 and the gain control unit 18 are automatically set. However, the phase control amount may be fixed and only the gain control amount may be automatically set. .
[0039]
FIG. 8 shows the configuration of a hearing aid according to another embodiment of the present invention.
[0040]
This hearing aid is composed of a hearing aid main body 1 and a relatively large control unit main body 30 that is configured separately from the hearing aid main body 1. The control unit main body 30 is, for example, a size and shape that can be stored in a breast pocket. Designed to.
[0041]
The control unit main body 30 includes a test sound source device including a test sound source 20, a driver 21, and a receiver 22, a pressure control unit 32 that controls air pressure to an air hole 31a of the ear canal contact unit 31 described later, a test switch 25, and a control unit. 26. In addition to this, a battery and the like are also incorporated. In this hearing aid, the leak sound is physically shut out and suppressed by adjusting the pressure of the air hole 31a of the ear canal contact portion 31 to an appropriate size and inflating the pressure to fit the ear canal 5.
[0042]
FIG. 9 shows a schematic structural diagram of the hearing aid.
[0043]
An air hole 31 a is provided in the ear canal contact portion 31 that contacts the ear canal 5, and the air hole 31 a and the pressure control portion 32 communicate with each other by a pressure control pipe 33. When the pressure of the air hole 31a is increased by the pressure control unit 32 via the pipe 33, the periphery of the ear canal contact portion 31 swells and the contact pressure with the ear canal 5 increases. Or a contact area becomes large. That is, the external auditory canal contact portion 31 acts to fit the external auditory canal 5. On the contrary, when the pressure of the air hole 31a is lowered, the contact pressure is reduced.
[0044]
The control unit 26 operates as follows.
[0045]
When the test switch 22 of the control unit main body 30 is turned on, the control unit 26 drives the test sound source 20 and emits a test sound for leak evaluation from the receiver 22 to the outside. At the same time, the control unit 26 stops the operation of the DSP signal processing unit 13 so that the sound whose speech speed has been converted is not emitted from the receiver 4 into the ear canal 5. The test sound for leak evaluation is picked up from the ear canal 5 by the ear canal microphone 23, and the degree of sealing of the hearing aid main body 3 with respect to the ear canal 5 is evaluated based on the detected sound. The sealing degree referred to in this embodiment is a physical sealing degree between the apparatus main body and the ear canal. The control unit 26 controls the pressure of the air hole 31 a by the pressure control unit 32 according to the evaluation result, and adjusts the degree of swelling of the ear canal contact unit 31. The control unit 26 stops the operation of the test sound source 20 when the level of the detection signal of the ear canal microphone 23 becomes minimum, starts the operation of the DSP signal processing unit 13, and sets the test switch 25 to an off state. To do. Thereafter, the normal operation mode is set, and the speech speed conversion process is performed on the external sound signal detected by the microphone 2 and is output from the receiver 4 into the ear canal 5.
[0046]
FIG. 10 is a flowchart showing the operation of the control unit 26. The difference from the flowchart shown in FIG. 7 is ST4 and ST6, which are different in whether the phase control amount and the gain control amount are adjusted or the pressure is adjusted. Others are the same. In the hearing aid shown in FIG. 9, the hearing aid main body 3 and the control unit main body 30 are configured separately. However, the hearing aid main body 3 and the control unit main body 30 can also be configured integrally. It can also be built in. In addition, when the pressure of the air hole 31a is set to an optimum state, if there is a problem such as feeling pain depending on the degree of the pressure, an upper limit value of the pressure set value can be set. It is. Furthermore, the hearing aid shown in FIG. 5 and the hearing aid shown in FIG. 8 may be combined. That is, it is also possible to suppress the leak sound generated in that state by inflating the ear canal contact portion 31 to a certain extent with the configuration shown in FIG.
[0047]
In the above-described embodiment, the speech speed conversion hearing aid that reduces the voice speed is shown. However, a speech speed conversion device that increases the voice speed may be used. In addition, the present invention is not limited to speech rate conversion hearing aids, but is also applied to external sound processing devices that perform digital sound processing different from external sounds, such as hearing aids with built-in digital filters that emphasize sound of a specific frequency. Applicable.
[0048]
【The invention's effect】
According to the first aspect of the present invention, the digital processing unit automatically adjusts according to the degree of sealing between the apparatus main body and the ear canal even when the apparatus is worn, even if the wearing state is bad or there is a gap between the device and the ear canal. Therefore, it is possible to suppress the leak sound optimally, and thereby automatically suppress the leak of the external sound , so that there is no inconvenience that it becomes difficult to hear the sound processed from the external sound.
[0050]
According to the invention of claim 2 , since the sealing degree is evaluated using the test sound source, the condition setting for suppressing the leak sound can be correctly performed in advance in the test mode.
[0051]
According to the invention of claim 3, the electroacoustic suppression can produce a suppression effect even if the adhesion between the apparatus main body and the ear canal is not very good. There is a point that it is not particularly necessary.
[0052]
According to the fourth and fifth aspects of the present invention, the leak sound into the ear canal is canceled by the phase and gain control, so that there is an advantage that the configuration for suppression is simple.
[0053]
In the invention of claim 6 , since the input microphone and the receiver of the digital processing unit and the suppression sound generation unit are common, the structure of the entire apparatus can be simplified.
[0054]
According to the seventh aspect of the present invention, even if the shape of the device main body does not match the ear canal, it can be adjusted by the adjusting portion, so that it is not necessary to individually make the shape of the device main body for each wearer, and the cost is reduced accordingly. Can contribute.
[Brief description of the drawings]
FIG. 1 is a diagram showing a wearing state of a hearing aid according to an embodiment of the present invention. FIG. 2 is a configuration diagram of the hearing aid. FIG. 3 is a functional block diagram of a DSP signal processing unit of the hearing aid. FIG. 5 is a block diagram of a hearing aid according to still another embodiment of the present invention. FIG. 6 is a structural diagram of the hearing aid. FIG. 7 is a flowchart showing the operation of the control unit of the hearing aid. 8 is a block diagram of a hearing aid according to still another embodiment of the present invention. FIG. 9 is a structural diagram of the hearing aid. FIG. 10 is a flowchart showing the operation of the control unit of the hearing aid.

Claims (7)

A digital processing unit that digitally processes the external sound and outputs it to the receiver;
Leak sound suppression means for suppressing the sound that the external sound leaks into the ear canal;
Instruction means for instructing the start of the sealing degree evaluation;
A sealing degree evaluation means for evaluating the sealing degree between the apparatus main body and the ear canal when receiving an instruction from the instruction means;
The leak sound suppression means is an external sound processing apparatus for ear wearing such as a hearing aid that performs suppression control of sound leaking according to the evaluated sealing degree . The sealing degree evaluation means includes
A test sound source device that generates a constant sound and outputs it to the outside;
An ear canal microphone that detects sound in the ear canal;
The external sound processing device for ear wearing such as a hearing aid according to claim 1 , further comprising means for stopping the operation of the digital processing unit and evaluating the sealing degree based on the detection sound of the ear canal microphone. 3. The external sound processing device for ear attachment such as a hearing aid according to claim 1, wherein the leak sound suppression unit includes a suppression sound generation unit that generates an electroacoustic suppression sound and outputs the generated sound to the receiver. . The external sound processing device for ear wearing according to claim 3 , wherein the suppression sound generation unit includes a phase control unit that generates a sound having a phase opposite to that of the external sound as a suppression sound. The external sound processing device for ear wearing such as a hearing aid according to claim 4 , wherein the suppression sound generation unit further includes a gain adjustment unit for adjusting a gain of the external sound. The input microphone and receiver digital processing unit and said suppressing sound generator are common earpiece for foreign sound processing device of the hearing aid or the like according to any one of claims 1-5. The leak sound suppressing means includes ear canal contact portion capable bulge outer periphery, and an adjusting unit that adjusts the degree of swelling of the ear canal contact portion earpiece of hearing aids according to any one of claims 1 or 2 Foreign sound processing equipment.

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