JP2014033298A - Electroacoustic transducer, muffled sound reduction device using the same and ear plugs, hearing aid, and audio earphone - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electroacoustic transducer for alleviating discomfort by reducing own voice echo and muffled feeling caused by sealing an external auditory canal.SOLUTION: An electroacoustic transducer whose sound output part 2 is a balanced armature type receiver and/or whose sound collection part 3 is an electret capacitor type microphone, includes the sound output part 2 that outputs sound to an external auditory canal and the sound collection part 3 that collects a sound in the external auditory canal, wherein a diaphragm 6 of the sound output part 2 and a diaphragm 7 of the sound collection part 3 share front chambers 8 and 9, and the diaphragm 6 of the sound output part 2 and the diaphragm 7 of the sound collection part 3 are facing to each other.

Description

  The present invention relates to an electroacoustic transducer that reduces a feeling of squeezing or pressure due to sealing of the ear canal, a squeezing reduction device using the electroacoustic transducer, an ear plug, a hearing aid, and an audio earphone.

When the ear canal is sealed with an ear-shaped hearing aid or earplug, the sound is not radiated to the space outside the ear canal.Speaking and chewing with food, etc. Etc. occur, and it is trapped in the external auditory canal, and there is a feeling of stagnation and pressure and is uncomfortable.

Here, the electroacoustic transducer itself that outputs sound is used as a receiver, and this receiver is built into a resin molded product, and what is attached to the ear using an earplug or the like is described as an earphone (eg, an audio earphone). To do. In addition, the sound in the ear canal, which is a factor such as a feeling of squeezing or pressure, due to the sound of the own voice or mastication generated by sealing the ear canal will be described as a squeaky sound. Also, the booming noise is a low frequency component of about 1 kHz or less.

As a countermeasure against the feeling of being stuffed or feeling of pressure, Patent Document 1 discloses a hearing aid in which a vent is formed so as to be maximized within a range where occurrence of howling can be suppressed.

  Patent Document 2 discloses a hearing aid device that provides a vibration detecting element for detecting vibration on the inner wall of the ear canal to generate a sound having an antiphase based on the vibration, and cancels the bulk sound as a response to the sound of the sound caused by sealing. Is disclosed.

In Patent Document 3, sound in the ear canal is converted into an electric signal in order to correct unnaturalness (so-called feeling of murmur) or the like caused by the sound of the user's voice being radiated into the ear canal in a sealed ear canal. The external ear canal microphone is incorporated separately from the receiver, and the output signal collected by the external ear canal microphone is compared with the output signal of the hearing aid processing means so that the output signal of the ear canal microphone approaches the output signal of the hearing aid processing means. A hearing aid is disclosed that includes signal processing means for automatically adjusting the output signal of the processing means.

JP 2008-199192 A JP 2004-48207 A JP 2007-235364 A

  However, in the hearing aid described in Patent Document 1, since a vent that communicates the inside and outside of the external auditory canal is formed, it is inevitable that sound in the external auditory canal is emitted through this vent, and gain is used as a response to howling. And the output sound pressure must be limited, so there may be cases where the sound pressure sufficient for hearing cannot be output.

In the hearing aid described in Patent Document 2, the vibration detection element hardly reacts to sound and detects vibrations of the inner wall of the wearer's ear canal. However, the vibration detection element itself or its mounting portion and the inner wall of the ear canal are detected. It is not easy to adhere to.

Further, in the hearing aid described in Patent Document 3, the receiver and the ear canal microphone are incorporated separately. In the case of such a hearing aid, on the receiver side, the sound generated from the diaphragm is guided into the ear canal through the narrow anterior chamber, the sound port, and the tube as a route. Then, on the ear canal microphone side, the sound in the ear canal is received by the diaphragm through the sound mouth and the tube and its narrow anterior chamber as a route. By passing through these paths, the sound transmission characteristics become complicated (the change in phase becomes large). For this reason, in order to make the output signal of the ear canal microphone automatically approach the output signal of the hearing aid processing means, advanced signal processing is required for automatic adjustment.

The techniques disclosed in Patent Literature 2 and Patent Literature 3 are intended to reduce the feeling of squeezing and the feeling of pressure by causing the receiver to emit a sound that cancels the squeaking sound in the ear canal. Therefore, advanced signal processing technology and large electric power are required.

  The present invention has been made in view of such problems of the prior art, and the object of the present invention is to reduce the feeling of bulkiness and pressure caused by sealing in the ear canal, It is an object of the present invention to provide a converter, a volume reduction device using the converter, an ear plug, a hearing aid, and an audio earphone.

In order to solve the above-mentioned problem, the invention according to claim 1 includes a sound output unit that outputs sound into the ear canal and a sound collection unit that collects sound in the ear canal, and the diaphragm of the sound output unit and the collector The diaphragm of the sound part shares the anterior chamber.

According to a second aspect of the present invention, in the electroacoustic transducer according to the first aspect, the diaphragm of the sound output unit and the diaphragm of the sound collection unit are opposed to each other.

The invention according to claim 3 is the electroacoustic transducer according to claim 1 or 2, wherein the sound output unit is a balanced armature type electroacoustic transducer and / or the sound collecting unit is an electret condenser type electroacoustic transducer. It is a converter.

According to a fourth aspect of the present invention, there is provided an electroacoustic transducer according to any one of the first to third aspects, a filter for extracting a predetermined low-frequency component from the output signal of the sound collection unit, and the extracted low frequency This is a fog reduction device that includes a low-frequency inverting amplification unit composed of an amplifier that inverts and amplifies a frequency component, and negatively feeds back the output signal of the low-frequency inverting amplification unit to the sound output unit.

The invention according to claim 5 includes the volume reduction device according to claim 4, wherein the sound output unit outputs sound into the external auditory canal and the sound collection unit collects sound in the external ear canal. It is an earplug in which a haze reduction device is provided.

According to a sixth aspect of the present invention, there is provided a volume reduction device according to the fourth aspect of the present invention, an external microphone that collects environmental sounds, an output signal of the external microphone that is subjected to hearing aid processing in accordance with the hearing ability of the wearer, and the low frequency range. The hearing reduction processing unit that amplifies the frequency component at a predetermined amplification factor, and the sound output unit outputs sound into the external auditory canal, and the volume reduction device is arranged so that the sound collection unit collects sound in the external ear canal. And a hearing aid that adds the output signal from the hearing aid processing unit to the output signal of the low frequency inversion amplification unit and inputs the added signal to the sound output unit.

According to a seventh aspect of the present invention, there is provided the correction device for inputting the volume reduction device according to the fourth aspect and an audio signal from the audio device, and the correction portion extracts a filter for extracting the low frequency component from the audio signal; An amplifier that amplifies the extracted low-frequency component at a predetermined amplification factor, and an adder that adds the amplified signal and the audio signal, and the sound output unit outputs sound into the ear canal, The volume reduction device is arranged so that the sound collecting unit collects the sound in the ear canal, and the output signal from the correction unit is added to the output signal of the low frequency inversion amplification unit, to the sound output unit This is an audio earphone for input.

The invention according to claim 8 is the hearing aid according to claim 6, wherein the hearing aid processing unit outputs a high frequency component of the output signal from the external microphone subjected to the hearing aid processing, and the high frequency component based on the output signal is output. A hearing aid provided with a high-frequency receiver that outputs sound into the ear canal.

The invention according to claim 9 is the audio earphone according to claim 7, wherein the audio earphone is provided with a high-frequency receiver that outputs the sound of the high-frequency component output from the audio device into the ear canal.

According to a tenth aspect of the present invention, in the earplug according to the fifth aspect, an acoustic resistance is provided in a sound input / output passage leading to the front chamber of the electroacoustic transducer.

According to an eleventh aspect of the present invention, in the hearing aid according to the sixth or eighth aspect, an acoustic resistance is provided in a sound input / output passage leading to the front chamber of the electroacoustic transducer.

According to a twelfth aspect of the present invention, in the audio earphone according to the seventh or ninth aspect, an acoustic resistance is provided in a sound entrance / exit passage leading to the front chamber of the electroacoustic transducer.

According to the first to third aspects of the invention, the phase difference of the output signal of the sound collecting unit with respect to the input signal of the sound output unit can be reduced.

According to the fourth aspect of the present invention, since the low frequency component whose phase is inverted from the sound output unit is output with respect to the output signal of the sound collection unit, the sound pressure in the front chamber can be lowered for this band. That is, if this electroacoustic transducer is arranged in the ear canal and the ear canal is sealed, the acoustic impedance in the front chamber is lowered for the band, so that the sound in the band is easily transmitted to the front chamber. Therefore, it is equivalent to the state in which the vent is provided while the external auditory canal is sealed, and the reverberation and the sound of the voice can be reduced, so that discomfort can be reduced.

According to the fifth aspect of the present invention, even when the ear canal is sealed with the earplug, it is possible to reduce discomfort due to a feeling of being obscured.

According to the invention of claim 6, it is equivalent to the state in which the vent is provided while the external auditory canal is sealed, and the feeling of cloudiness can be reduced, so that discomfort can be reduced and the hearing aid can be sealed. Since no howling due to the sound leaking from the gap is generated, it is possible to make the wearer hear a louder sound than a hearing aid such as that of Patent Document 1.

According to the seventh aspect of the present invention, when the cloud reduction device is used for the audio earphone, even if the ear canal is sealed, it is possible to reduce unpleasant sensation due to a feeling of cloudiness.

According to the invention according to claim 8 or claim 9, since it is possible to reduce the oscillation of the volume reduction device due to the high frequency component, the amplification factor of the amplifier of the volume reduction device can be increased. Reduction effect is improved.

According to the inventions according to claims 10 to 12, since the peak of the high frequency component can be suppressed by providing the acoustic resistance in the sound entrance / exit passage leading to the front chamber, the volume reduction device oscillates with the high frequency component. This can be suppressed, and the amplification factor of the amplifier of the cloud reduction device can be increased, so that the effect of reducing the cloud noise is improved.

Sectional view of an electroacoustic transducer according to the present invention Sectional drawing of another embodiment of the electroacoustic transducer according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining the principle of a cloud reduction device, where FIG. Block configuration diagram of the cloud reduction device according to the present invention Block diagram of an earplug provided with a device for reducing the volume according to the present invention Block diagram of a hearing aid equipped with a haze reduction device according to the present invention The block block diagram of the earphone for audios provided with the volume reduction apparatus which concerns on this invention Block diagram of a hearing aid equipped with a haze reduction device and a high frequency receiver according to the present invention Cross section of electroacoustic transducer with acoustic resistance

Embodiments of the present invention will be described below with reference to the accompanying drawings. As shown in FIG. 1, the electroacoustic transducer 1 according to the present invention includes a sound output unit 2 that outputs sound and a sound collection unit 3 that collects sound.

The electroacoustic transducer 1 is desirably smaller in size so that it can be inserted into the ear canal. For example, as the sound output unit 2, a balanced armature type receiver for a hearing aid is applied, As the sound collection unit 3, an electret condenser microphone is applied. 6 and 7 are diaphragms, 8 is an armature, 9 and 10 are magnets, 11 is a yoke, 12 is a coil, and 18 is an impedance converter.

  In the electroacoustic transducer 1, a front chamber 15 is provided between a sound output unit 2 that generates sound and a sound collection unit 3 that collects sound. This front chamber 15 is common to the diaphragms 6 and 7. It becomes space to do. The diaphragm 6 and the diaphragm 7 are opposed to each other with the front chamber 15 interposed therebetween.

In FIG. 1, the diaphragm 7 is made smaller than the diaphragm 6 and the sound collecting unit 3 is located closer to the sound inlet / outlet 16, but the diaphragm 6 and the diaphragm 7 may be the same size as shown in FIG. As long as the diaphragm 6 of the output unit 2 and the diaphragm 7 of the sound collecting unit 3 face a common space (a space where the transfer function from the diaphragm 6 to the diaphragm 7 can be regarded as almost 1), the sound output unit The size relationship between 2 and the sound collection unit 3 and the component configuration are not limited.

  The sound port 17 connects the electroacoustic transducer 1 and a tube that becomes a sound path of the apparatus. However, the sound port 17 is not essential, and for example, the electroacoustic transducer 1 can be directly disposed on a main body such as a hearing aid or earplug without using a tube.

  By configuring the electroacoustic transducer 1 in this way, when the sound output unit 2 generates sound, since the front chamber 15 is a common space for the diaphragms 6 and 7, the sound is directly collected by the sound collection unit 3. By collecting the sound, the phase difference between the input signal of the sound output unit 2 and the output signal of the sound collection unit 3 can be reduced. In order to obtain more effects, the surfaces of the diaphragm 6 and the diaphragm 7 should be opposed to each other in a more nearly parallel state. In addition, a booming sound generated in the ear canal is collected by the sound collection unit 3.

  The sound output unit 2 may be an electrodynamic or electromagnetic receiver, and the sound collection unit 3 may be a MEMS (Micro Electro Mechanical Systems) microphone or an electrodynamic, condenser or piezoelectric microphone. . For example, in the case of an earphone for audio, an electrodynamic receiver is generally used for the sound output unit, but the sound collecting unit faces the space that becomes the front chamber with respect to the diaphragm. A microphone diaphragm is provided. Preferably, it arrange | positions so that each diaphragm may oppose. There are various parts configurations for this arrangement.

Next, the principle of the fog reduction device to which the electroacoustic transducer 1 is applied will be described. As shown in FIG. 3 (a), in the hearing aid of Patent Document 3, which is a prior art, the sound output unit (receiver) 100 and the sound collection unit (microphone for ear canal) 101 are separate and do not share a space (anterior chamber). case is present in the ear canal, tube, sound ports, front chamber negative feedback loop transfer characteristic H _R and the transfer characteristics H _M of the external auditory canal microphone side of the receiver side using the low-frequency inverting amplifier 102 due. Reference numeral 103 denotes an impedance of a path through which sound in the oral cavity reaches the ear canal.

When such transfer characteristic H _R and the transfer characteristics H _M is present in the negative feedback loop of the reduction device muffled, the phase is changed easily between the output voltage of the input voltage and the external ear canal microphone 101 of the receiver 100, the external auditory canal from the receiver 100 In order to output a sound that cancels the internal noise, the low-frequency inversion amplification unit 102 requires advanced signal processing.

On the other hand, as shown in FIG. 3B, in the case of the electroacoustic transducer 1 according to the present invention comprising the sound output unit 2 and the sound collection unit 3 sharing the front chamber 15, the diaphragm of the sound output unit 2 since 6 and the diaphragm 7 of the sound collecting portion 3 faces the common space (front chamber 15), a negative feedback loop using the low-frequency inverted amplifying portion 20, the transfer characteristic H _R and the transfer characteristics H _M Almost does not exist. Therefore, the low frequency inverting amplification unit 20 does not require advanced signal processing. Incidentally, H _I is the transfer characteristic of the tube and the sound opening between the front chamber 15 and the ear canal 22.

The volume reduction device 21 according to the present invention reduces the volume noise in the ear canal 22, and includes the electroacoustic transducer 1 and the low frequency inversion amplification unit 20 as shown in FIG. The output signal of one sound collection unit 3 is processed by the low frequency inversion amplification unit 20 and negatively fed back to the input signal of the sound output unit 2. The low-frequency inverting amplification unit 20 includes a filter that extracts a predetermined low-frequency component and an amplifier that inverts and amplifies the output signal of the filter at a predetermined amplification factor.

The operation of the mass reduction device 21 configured as described above will be described. The electroacoustic transducer 1 is disposed in the sealed external auditory canal 22, and the muffled sound is collected by the sound collecting unit 3 of the electroacoustic transducer 1, and the low frequency inversion amplification unit 20 is output from the output signal of the sound collecting unit 3. A predetermined low-frequency component is extracted by the above filter. The extracted signal of the low frequency component is inverted and amplified at a predetermined amplification factor by the amplifier of the low frequency inverting amplifier 20 and input to the sound output unit 2 of the electroacoustic transducer 1.

Then, a sound having a phase opposite to that of the muffled sound is output to the front chamber 15 of the electroacoustic transducer 1, and the muffled sound is reduced in the front chamber 15 according to the amplification factor. In other words, the reduction of the low-frequency component muffled noise in the front chamber 15 is due to lowering the acoustic impedance (pressure / velocity) of the low-frequency in the front chamber 15. Since the anterior chamber 15 and the ear canal 22 communicate with each other, the muffled sound of the low frequency component in the ear canal 22 is easily transmitted to the anterior chamber 15 having low acoustic impedance. In other words, even if the outer ear canal 22 is sealed, it is the same as communicating with the outside through a vent, so that a feeling of stagnation and a feeling of pressure are reduced.

  Next, as shown in FIG. 5, the earplug 30 to which the volume reduction device 21 is applied includes an electroacoustic transducer 1, a low-frequency inversion amplification unit 20, a power supply source (not shown) such as a battery, and the like. The output signal of the sound collection unit 3 of the electroacoustic transducer 1 is processed by the low frequency inversion amplification unit 20 and negatively fed back to the input signal of the sound output unit 2. The electric circuit of the fog reduction device 21 may be configured by either an analog circuit or a digital circuit. The main body (not shown) of the earplug 30 is formed of a resin material such as silicon, urethane, or ABS so as to fit the inner wall of the ear canal.

Since the operation of the earplug 30 to which the cloud reduction device 21 is applied is the same as that of the cloud reduction device 21, description thereof is omitted. The earplug 30 is used for sound insulation when surrounding noise is a concern. However, when the ear canal is sealed, it is uncomfortable with a feeling of squeezing and pressure.

In the earplug 30, the volume reduction device 21 reduces the volume noise, so that the inside of the external auditory canal 22 is the same as being opened even if it is sealed, so that the feeling of volume and pressure can be reduced. Moreover, not only the booming sound but also the sound that enters the ear canal 22 from around the head can be effectively reduced.

Next, as shown in FIG. 6, the hearing aid 40 to which the volume reduction device 25 is applied houses the external microphone 41, the hearing aid processing unit 42, the volume reduction device 25, the correction unit 27, and the like in a hearing aid body (not shown). It becomes. The hearing aid processing unit 42 is configured by a DSP (Digital Signal Processor) or the like. The cloud reduction device 25 includes the electroacoustic transducer 1, a low frequency inversion amplification unit 26, and an addition unit 28.

The electric circuit of the fog reduction device 25 may be constituted by either an analog circuit or a digital circuit. As the hearing aid 40, the present invention can be applied to an earphone type hearing aid, a RIC (Receiver in the canal) type hearing aid in which a receiver is disposed in the ear canal, a pocket type hearing aid, or the like.

The external microphone 41 collects environmental sounds and speech and converts them into electrical signals. The hearing aid processing unit 42 performs hearing aid processing such as adjusting the amplification factor for each frequency in order to match the electrical signal from the external microphone 41 with the hearing ability of the wearer, and outputs a hearing aid processing signal. The sound collection unit 3 of the electroacoustic transducer 1 collects the sound in the ear canal 22 and converts it into an electrical signal. The sound in the ear canal 22 is a combination of the volume sound and the output sound (hearing aid processing sound) from the sound output unit 2 based on the hearing aid processing signal.

The filter of the low frequency inversion amplification unit 26 extracts a predetermined low frequency component from the output signal of the sound collection unit 3 of the electroacoustic transducer 1. Therefore, components other than the low frequency component are not subjected to negative feedback processing by the cloud reduction device 25. The amplifier of the low-frequency inverting amplifier 26 inverts and amplifies the extracted low-frequency component signal with a predetermined amplification factor. The adder 28 adds the output signal of the low-frequency inverting amplifier 26 and the output signal of the correction unit 27.

The correction unit 27 extracts the same low frequency component as the filter of the low frequency inversion amplification unit 26 from the hearing aid processing signal, the amplifier 27b that amplifies the low frequency component with a predetermined amplification factor, and this amplification. An adder 27c for adding the signal and the hearing aid processing signal is provided. The low frequency component extracted from the hearing aid processing signal is amplified, and an output signal added with the hearing aid processing signal is output.

  Since the sound collection unit 3 collects the hearing aid processing sound together with the muffled sound, the low frequency component of the hearing aid processing signal processed by the hearing aid processing unit 42 is reduced by the low frequency component inverted and amplified by the negative feedback processing. The correction unit 27 is for correcting the reduction. The sound output unit 2 emits sound in the ear canal 22 based on a signal obtained by adding the output signal of the correction unit 27 and the output signal of the low frequency inversion amplification unit 26. The low frequency component amplification processing in the correction unit 27 may be performed by the hearing aid processing unit as part of the hearing aid processing.

  The operation of the hearing aid 40 configured as described above will be described. First, the external microphone 41 collects environmental sounds and speech and converts them into electrical signals. The hearing aid processing unit 42 performs hearing aid processing such as adjusting the amplification factor for each frequency in accordance with the output signal of the external microphone 41 according to the hearing ability of the wearer, and outputs a hearing aid processing signal.

  In the electroacoustic transducer 1, the sound and the hearing aid processing sound in the ear canal 22 are collected by the sound collection unit 3 and an output signal that is an electrical signal is output. In the low frequency inverting amplification unit 26, the low frequency component is extracted from the output signal of the sound collecting unit 3 with a filter. The extracted low frequency component signal is inverted and amplified by the amplifier at the amplification factor and output.

In the correction unit 27, the low frequency signal is extracted from the hearing aid processing signal by the filter 27a, and the low frequency component extracted by the amplifier 27b with the amplification factor corresponding to the reduced amount of the hearing aid processing sound. Are added to the hearing aid processing signal by the adder 27c and output.

A signal obtained by adding the output signal from the low frequency inversion amplification unit 26 and the output signal from the correction unit 27 is input to the sound output unit 2 of the electroacoustic transducer 1, so that the noise in the ear canal 22 is reduced. The hearing aid processing sound can obtain the original volume. In other words, the reduction of the low-frequency component muffled sound in the front chamber 15 is due to lowering the acoustic impedance (pressure / velocity) of the low-frequency in the front chamber 15, and the wearer is allowed to enter the ear canal 22. Even if is sealed, it is possible to obtain the same effect as when the vent is opened and to hear a sufficient hearing aid processing sound.

  In addition, the sound output unit 2 and the sound collection unit 3 of the electroacoustic transducer 1 share the space that is the front chamber 15 and the respective diaphragms 6 and 7 are operated, so that the phase shift occurs in the low frequency component. Since it falls within 90 °, this phase shift need not be taken into account even when negative feedback processing is performed. When a large negative feedback is applied, the sound output unit 2 and the sound collection unit 3 are less likely to oscillate as compared to a separate unit. In order to obtain more effects, the surfaces of the diaphragm 6 and the diaphragm 7 should be opposed to each other in a state of being almost parallel.

As described above, when the electroacoustic transducer 1 according to the present invention is used, even if the inside of the ear canal 22 is sealed with the volume reduction device 25 having a simple configuration, the volume noise is reduced in the same manner as the vent is provided. It is possible to reduce uncomfortable feelings such as a feeling of being crowded and a feeling of pressure. In addition, since the inner ear canal 22 is sealed, no howling due to sound leaking from the gap between the hearing aid and the ear canal occurs, so that a louder sound can be output than when a vent is actually provided.

  Next, as shown in FIG. 7, the audio earphone 50 to which the volume reduction device is applied includes a volume reduction device 25 and a correction unit 27 in an audio earphone body (not shown). The cloud reduction device 25 includes an electroacoustic transducer 1, a low-frequency inversion amplification unit 26, and an addition unit 28.

The electric circuit of the fog reduction device 25 may be constituted by either an analog circuit or a digital circuit. The sound in the ear canal 22 is a combination of the volume sound and the audio sound from the sound output unit 2 based on the audio signal. Reference numeral 55 denotes an audio device. Note that the low frequency inversion amplification unit 26 and the correction unit 27 may be provided in the audio device 55.

In the audio earphone 50, the external microphone 41 and the hearing aid processing unit 42 are not used as compared with the hearing aid 40, but the audio signal corresponds to the hearing aid processing signal. Since the operation of the audio earphone 50 is the same as that of the hearing aid 40, the description thereof is omitted.

The audio earphone 50 is used when listening to music or learning a language. However, when a voice is uttered, it is uncomfortable due to a cloudy sound (such as the sound of its own voice) generated in the ear canal 22 and a feeling of volume and pressure. In the audio earphone 50, the volume reduction device 25 reduces the volume noise, so that the inside of the ear canal 22 is the same as being open even if it is sealed, so that it is possible to reduce the feeling of volume and pressure.

  Next, as shown in FIG. 8, a hearing aid 60 provided with a high frequency receiver for high frequency components not subjected to negative feedback processing includes an external microphone 61, a hearing aid processing unit 62, a volume reduction device 63, and a correction unit. 67, and a high-frequency receiver 64 that outputs a sound of a high-frequency component to the inner ear canal 22. The cloud reduction device 63 includes an electroacoustic transducer 65, a low-frequency inversion amplification unit 66, and an addition unit 68.

The electroacoustic transducer 65 includes a sound collection unit 69 and a sound output unit 70. The low-frequency inverting amplifier 66 includes a filter that extracts a predetermined low-frequency component and an amplifier that amplifies the low-frequency component. The correction unit 67 includes an amplifier 67a and may be provided inside the hearing aid processing unit 62 or may be provided outside. Here, it is provided inside the hearing aid processing unit 62.

  In the hearing aid processing unit 62, a predetermined low frequency component based on the hearing aid processing signal subjected to the hearing aid processing such as adjusting the amplification factor for each frequency according to the hearing ability of the wearer according to the electrical signal from the external microphone 61 is negative. A low frequency hearing aid processing signal amplified by the amount reduced by the feedback processing and a high frequency hearing aid processing signal having a high frequency component are output. The low frequency hearing aid processing signal is added to the output signal from the low frequency inversion amplification unit 66. The negative feedback processing of the cloud reduction device 63 is the same as that of the hearing aid 40 and will not be described.

Further, the high frequency hearing aid processing signal is input to the high frequency receiver 64, and the high frequency hearing aid processing sound is output to the inner ear canal 22. By providing the low-frequency sound output unit 70 and the high-frequency receiver 64 of the electroacoustic transducer 65, the low-frequency component 63 only needs to process the low-frequency component, and the high-frequency component of the sound output unit 70 can be processed. Since it is not affected by a large change in phase depending on the peak characteristics or the like, it becomes difficult to oscillate, the amplification factor of the amplifier of the low-frequency inverting amplifier 66 can be increased, and the muffled sound can be reduced more effectively.

That is, the further reduction of the low-frequency component muffled sound is due to lowering the acoustic impedance (pressure / velocity) of the low-frequency in the anterior chamber 15, and the wearer seals the inner ear canal 22. Even if it is open, the original hearing aid processing sound can be heard in the same manner as when the vent is opened.

  Also, an audio earphone provided with a high-frequency receiver for high-frequency components that is not subject to negative feedback processing is similar to the above-described hearing aid 60 by dividing the audio signal into low-frequency components and high-frequency components. An effect can be obtained.

Further, as shown in FIG. 9, an acoustic resistance (for example, 2000 ohm) 19 is provided at the sound port 17 of the electroacoustic transducer 1, 65, and the cloud reduction devices 21, 25, 63 are connected to the earplug 30, the hearing aid. 40, 60, and can be applied to the audio earphone 50.

Since the peak of the high frequency component can be suppressed by providing the acoustic resistance 19, it is possible to suppress the lumping reduction devices 21, 25, 63 from oscillating due to the high frequency components. Since the amplification factor of the amplifier can be increased, the effect of reducing the booming noise is improved. The acoustic resistor 19 is not limited to the sound port 17 and may be provided in any sound entry / exit passage (for example, a tube) that communicates with the front chamber 15.

Thus, when provided with the acoustic resistance 19, the resistance value be about 2000 [Omega, H _I is the transfer characteristic of the tube and the sound opening between the front chamber 15 and the ear canal 22, little effect.

  According to the present invention, the ear canal is provided with an electroacoustic transducer having a structure facing a space in which the diaphragm of the sound output unit and the diaphragm of the sound collecting unit face each other, and a volume reduction device using the electroacoustic transducer. It is possible to provide an earplug, a hearing aid, and an audio earphone that can reduce discomfort due to a feeling of being obscured even if the device is sealed.

DESCRIPTION OF SYMBOLS 1,65 ... Electroacoustic transducer, 2,70 ... Sound output part, 3,69 ... Sound collecting part, 6,7 ... Diaphragm, 15 ... Front chamber, 16 ... Sound inlet / outlet, 17 ... Sound outlet, 18 ... Impedance Transducer, 19 ... acoustic resistance, 20,26,66 ... low frequency inverting amplification unit, 21,25,63 ... cutter reduction device, 22 ... inside ear canal, 27,67 ... correction unit, 28,68 ... addition unit, 30 ... earplugs, 40, 60 ... hearing aids, 41, 61 ... external microphones, 42, 62 ... hearing aid processing units, 50 ... audio earphones, 55 ... audio devices, 64 ... receivers for high frequencies.

Claims (12)

A sound output unit that outputs sound into the ear canal and a sound collection unit that collects sound within the ear canal, and the diaphragm of the sound output unit and the diaphragm of the sound collection unit share the front chamber An electroacoustic transducer characterized by. 2. The electroacoustic transducer according to claim 1, wherein a diaphragm of the sound output unit and a diaphragm of the sound collecting unit are opposed to each other. The electroacoustic transducer according to claim 1 or 2, wherein the sound output unit is a balanced armature type electroacoustic transducer and / or the sound collecting unit is an electret condenser type electroacoustic transducer. Electroacoustic transducer to do. 4. The electroacoustic transducer according to claim 1, a filter for extracting a predetermined low-frequency component from an output signal of the sound collecting unit, and an amplifier for inverting and amplifying the extracted low-frequency component. A low-frequency inverting amplification unit comprising: a low-frequency inverting amplification unit, wherein the output signal of the low-frequency inverting amplification unit is negatively fed back to the sound output unit. 5. The apparatus of claim 4, wherein the sound output unit outputs sound into the external auditory canal and the sound collection unit collects the sound in the external auditory canal. Earplug characterized by. 5. The apparatus for reducing a volume according to claim 4, an external microphone for collecting environmental sound, a hearing aid process for the output signal of the external microphone according to the hearing ability of the wearer, and the low frequency component at a predetermined amplification factor. A hearing aid processing unit that amplifies, and the sound output unit outputs sound into the external auditory canal, and the volume reduction device is disposed so that the sound collection unit collects sound in the external auditory canal. Is added to the output signal of the low-frequency inversion amplification unit and input to the sound output unit. 5. The apparatus according to claim 4, further comprising: a correction unit that inputs an audio signal from the audio device, wherein the correction unit extracts the low frequency component from the audio signal, and the extracted low frequency component And an adder for adding the amplified signal and the audio signal, the sound output unit outputs sound into the ear canal, and the sound collecting unit is a sound in the ear canal. The above-mentioned volume reduction device is arranged so as to collect sound, and the output signal from the correction unit is added to the output signal of the low frequency inversion amplification unit and input to the sound output unit Earphone for. 7. The hearing aid according to claim 6, wherein the hearing aid processing unit outputs a high frequency component of the output signal from the external microphone subjected to hearing aid processing, and outputs a high frequency component sound based on the output signal into the ear canal. Hearing aid characterized by providing an area receiver. 8. The audio earphone according to claim 7, further comprising a high-frequency receiver that outputs a high-frequency component sound output from the audio device into the ear canal. 6. The auricle according to claim 5, wherein an acoustic resistance is provided in a sound entrance / exit passage leading to the anterior chamber of the electroacoustic transducer. The hearing aid according to claim 6 or 8, wherein an acoustic resistance is provided in a sound entrance / exit passage leading to the anterior chamber of the electroacoustic transducer. 10. The audio earphone according to claim 7, wherein an acoustic resistance is provided in a sound input / output passage that communicates with the front chamber of the electroacoustic transducer. 11.

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