JP2014165688A - Hearing aid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hearing aid that hardly suffers from occurrence of howling ascribable to sound returning from an earphone to a microphone without using complicated signal processing.SOLUTION: The hearing aid includes: a microphone 4; a hearing aid processing part 5 for performing hearing aid processing on an output signal of the microphone 4; a first earphone 8 that outputs sound on the basis of an output signal of the hearing aid processing part 5; a delay part 6 for delaying the output signal of the hearing aid processing part 5; and a second earphone 7 that outputs sound on the basis of an output signal of the delay part 6, with the microphone 4 being positioned in an area A where the sound outputted from the second earphone 7 cancels the sound outputted from the first earphone 8. The first earphone 8 is arranged in an external auditory meatus 10 so as to be directed toward an eardrum side and the second earphone 7 is arranged in the external auditory meatus 10 so as to be directed toward an external world side.

Description

  The present invention relates to a hearing aid that suppresses howling caused by sound returning from an earphone to a microphone.

  Conventionally, various howling suppression techniques have been proposed for hearing aids. Patent Document 1 describes a hearing aid that suppresses howling by detecting a feedback signal in an input signal by modulating the output signal and processing the input signal in relation to the detected feedback signal. Yes.

Patent Document 2 discloses an adaptive device configured to estimate a feedback path existing between a receiver and a microphone with an adaptive filter and reduce at least a part of the feedback signal in a hearing device including a receiver and a microphone. A hearing aid with a feedback canceller is described.

JP 2006-115509 A JP 2011-254468 A

In any of the techniques described in Patent Document 1 and Patent Document 2, since the component output from the earphone included in the sound collected by the external microphone is extracted and removed, the howling is suppressed. Signal processing is required.

  The present invention has been made in view of such problems of the prior art, and the object of the present invention is howling caused by sound returning from the earphone to the microphone without using complicated signal processing. It is intended to provide a hearing aid that is difficult to generate.

In order to solve the above-mentioned problem, the invention according to claim 1 is a microphone, a hearing aid processing unit that performs hearing aid processing on the output signal of the microphone, a first earphone that outputs sound based on the output signal of the hearing aid processing unit, A delay unit that delays the output signal of the hearing aid processing unit; and a second earphone that outputs a sound based on the output signal of the delay unit, and the position of the microphone is determined by the sound output from the second earphone. The sound output from the first earphone is an area where the sound is reduced.

  By adjusting the amount of delay by the delay unit, it is possible to change the region in which the sound output from the first earphone is reduced.

In addition, the first earphone and the second earphone can be disposed in the ear canal.

According to the present invention, since the position of the microphone becomes a position where the sound output from the first earphone is reduced by the sound output from the second earphone, howling is suppressed without using complicated signal processing. be able to.

In addition, by adjusting the delay amount of the sound of the second earphone, it is possible to change the region where the sound output from the first earphone is reduced, so that it is possible to suppress howling in accordance with the shape of the user's ear. Become.

Further, if the first earphone and the second earphone are arranged in the ear canal, the position of the microphone is at a position where the sound output from the first earphone leaking from the vent due to the sound output from the second earphone is reduced. Therefore, howling can be suppressed without using complicated signal processing.

Schematic configuration diagram of a hearing aid type hearing aid to which the present invention is applied Illustration of polar pattern Action diagram of polar pattern Action explanatory diagram of the ear-hearing type hearing aid to which the present invention is applied In the explanatory diagram of other polar patterns, (a) when the delay amount is changed, (b) when the delay amount is further changed In the explanatory diagram of the action of other polar patterns, (a) when the delay amount is changed, (b) when the delay amount is further changed

Embodiments of the present invention will be described below with reference to the accompanying drawings. As shown in FIG. 1, the ear-mounted hearing aid 1 to which the present invention is applied includes a hearing aid body 2, an earplug 3, a tube member (not shown) that connects the hearing aid body 2 and the earplug 3, and the like.

The hearing aid main body 2 includes a microphone 4 that collects sound and a DSP (Digital Signal Processor). The hearing aid processing unit 5 that performs signal processing such as amplification on the output signal of the microphone 4 and the output signal of the hearing aid processing unit 5 Components such as a delay unit 6 for delaying are accommodated.

The DSP has a storage unit (not shown) that stores various settings. Various settings stored in the storage unit can be changed by connecting an adjustment device such as a personal computer to the hearing aid 1. By changing the setting relating to the delay stored in the storage unit, the delay amount of the output signal of the hearing aid processing unit 5 by the delay unit 6 can be adjusted.

The earplug 3 houses a first earphone 8 that outputs sound based on the output signal of the hearing aid processing unit 5 and a second earphone 7 that outputs sound based on the output signal of the delay unit 6. When the ear-mounted hearing aid 1 is worn, the earplug 3 is mounted in the ear canal 10, and the output sound from the first earphone 8 is guided to the ear canal 10. The earplug 3 may be an off-the-shelf product or an ear mold adapted to the shape of the wearer's ear canal.

  The microphone 4 is electrically connected to the input unit of the hearing aid processing unit 5 through the wiring 11 a, the first earphone 8 is electrically connected to the output unit of the hearing aid processing unit 5 through the wiring 11 b, and the second earphone 7 is connected to the delay unit 6. Is electrically connected to the output part of the hearing aid processing part 5 via the wiring 11c.

  By the way, the sound output from the first earphone 8 leaking from the gap between the ear canal 10 and the earplug 3 may be input to the microphone 4 and cause howling. Moreover, when the vent 9 is formed in the earplug 3, the sound leaked from the outside 9a of the vent 9 may cause howling. In the embodiment of the present invention, the latter case will be described.

FIG. 2 shows the sound output from the first earphone 8 leaking from the outside exit 9a of the vent 9 and the sound output from the sound port 7a of the second earphone 7 whose delay amount is adjusted to a predetermined value by the delay unit 6. The state of the interaction of the sound is shown. The sound pressure of the sound output from the sound port 7a of the second earphone 7 may be approximately the same as the sound pressure of the sound output from the first earphone 8 leaking from the outside 9a of the vent 9. Therefore, it is sufficient that the second earphone 7 is smaller than the first earphone 8.

  The polar pattern 12 represents the magnitude of sound pressure observed by a microphone (not shown) disposed on a circumference 14 indicated by a dotted line centered on the outside exit 9a of the vent 9 as a center 13. The distance D from the center 13 to the curve 12a of the polar pattern 12 represents the magnitude of the sound pressure observed by the microphone arranged on the circumference 14 indicated by the dotted line.

For example, when such a polar pattern 12 is formed, as shown in FIG. 3, an area A in which the center 13 can directly face without being blocked by the curve 12 a outside the area surrounded by the curve 12 a of the polar pattern 12. Then, since the sound output from the sound port 7a of the second earphone 7 cancels the sound output from the first earphone 8 leaking from the outside 9a of the vent 9, the sound pressure output from the first earphone 8 is It is hardly observed.

Therefore, as shown in FIG. 4, if the microphone 4 is arranged outside the area surrounded by the curve 12a of the polar pattern 12 in the area A where the center 13 can directly face without being blocked by the curve 12a of the polar pattern 12, It is possible to reduce the sound output from the first earphone 8 leaking from the external side outlet 9 a of the vent 9 from returning to the microphone 4.

  Further, the polar pattern can be changed by adjusting the delay amount of the delay unit 6. In addition to the polar pattern 12, the polar pattern 20 shown in FIG. 5A and the polar pattern shown in FIG. 21 or the like can be formed.

These polar patterns 20 and 21 also represent the magnitude of sound pressure observed with a microphone (not shown) arranged on a circumference 14 indicated by a dotted line centered on the outside exit 9 a of the vent 9. The distance D from the center 13 to the curves 20a and 21a of the polar patterns 20 and 21 represents the magnitude of the sound pressure observed by the microphone arranged on the circumference 14 indicated by the dotted line.

  Also in these polar patterns 20 and 21, as shown in FIG. 6, outside the area surrounded by the curves 20a and 21a of the polar patterns 20 and 21, the outside of the vent 9 is not blocked by the curves 20a and 21a. In the regions B and C where the center 13 which is the position of the outlet 9a directly faces, the sound output from the second earphone 7 cancels the sound output from the first earphone 8 leaking from the external side outlet 9a of the vent 9. The sound pressure output from the first earphone 8 is hardly observed.

The polar patterns 12, 20, and 21 listed here are merely examples, and by adjusting the delay amount of the delay unit 6, areas such as A, B, and C in which the sound pressure is reduced are set at desired positions. can do.

Accordingly, regions A and B in which the sound output from the second earphone 7 cancels the sound output from the first earphone 8 leaked from the external side outlet 9a of the vent 9 at the position of the microphone 4 of the ear hearing aid 1. , C may be adjusted so that the delay amount of the delay unit 6 is adjusted to form the desired polar patterns 12, 20, 21.

In other words, since the polar pattern can be changed by adjusting the delay amount of the delay unit 6, it is possible to easily configure the ear-hearing type hearing aid 1 that suppresses howling in accordance with the shape of the user's ear. .

  According to the present invention, by arranging the microphone in a region where the sound output from the second earphone cancels the sound output from the first earphone, howling can be suppressed without using complicated signal processing. A hearing aid can be provided.

DESCRIPTION OF SYMBOLS 1 ... Hearing type hearing aid, 2 ... Hearing aid main body, 3 ... Ear plug, 4 ... Microphone, 5 ... Hearing aid processing part, 6 ... Delay part, 7 ... 2nd earphone, 7a ... Sound outlet, 8 ... 1st earphone, 9 ... Vent, 9a ... External side exit, 10 ... Ear ear canal, 11a, 11b, 11c ... Wiring, 12, 20, 21 ... Polar pattern, 12a, 20a, 21a ... Curve, 13 ... Center, 14 ... Circle, A, B , C ... area.

Claims (3)

A microphone, a hearing aid processing unit that performs hearing aid processing on the output signal of the microphone, a first earphone that outputs sound based on the output signal of the hearing aid processing unit, and a delay unit that delays the output signal of the hearing aid processing unit; A second earphone that outputs sound based on the output signal of the delay unit is provided, and the position of the microphone is within a region where the sound output from the second earphone cancels the sound output from the first earphone. Hearing aid characterized by that. The hearing aid according to claim 1, wherein the position of the region is changed by adjusting a delay amount by the delay unit. 3. The hearing aid according to claim 1, wherein the first earphone is disposed toward the eardrum side and the second earphone is disposed toward the outside world in the external auditory canal.

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