JP3947524B2 - Earphone with microphone for hearing aid - Google Patents

Description

  The present invention relates to an earphone with a microphone for hearing aid used by a hearing impaired person, and it is possible to prevent howling from occurring even when used for a high-output type hearing aid for a highly hearing-impaired person. The present invention relates to an earphone with a microphone for hearing aid.

  Conventionally, hearing aids used by persons with hearing impairments have basically heard a person's speech and surrounding sounds with a microphone, and the sound heard with the microphone has been amplified by an amplifier and inserted into the ear canal of the ear. It is configured to play back with an earphone. People collect voices and surrounding sounds with the pinna protruding outside the ears and listen to them with the eardrum through the ear canal, so a hearing aid microphone is also placed at the entrance of the ear canal. Desirably, the sound collecting function by the pinna of the ear acts at the entrance of the ear canal, so that there is an advantage that the sound can be heard clearly. A hearing aid of the type in which a microphone, an earphone and an amplifier are integrated in a small size and inserted into an ear hole (hereinafter referred to as “ear hole type hearing aid”) is an example of a hearing aid having the above-described advantages.

  By the way, the above-mentioned ear-hole type hearing aid has an advantage that it is possible to listen to sound clearly by using the sound collecting function by the pinna of the ear and can be downsized. Since both the microphone and the earphone are located at the position, and the distance between the microphone and the earphone is short, there is a possibility that howling will occur if the amplification gain of the hearing aid is increased especially for a highly deaf person. .

  In addition, in the case of the above-mentioned ear hole type hearing aid, the auricle reflects the sound leaking to the outside through the earphone main body case so that it can be understood that the shape of the auricle is observed except for the reason that the distance between the microphone and the earphone is short. As a result, the sound pressure around the microphone is increased, and a structure in which howling is likely to occur is obtained.

  Therefore, the ear-hook type or ear-hole type hearing aid as a hearing aid for advanced hearing loss (a hearing aid that further increases the amplification gain of the hearing aid) is an exterior that is used for the box-type hearing aid described below due to the structure of the earphone. Compared to earphones, output characteristics are degraded, and it is said that the performance of listening to words is not good.

  As a solution to the above problems, conventionally called a box-type hearing aid (a hearing aid amplifier and a microphone are integrated to form a box-shaped main body, and a cord for the earphone is output from the box-shaped main body, A hearing aid with a structure in which a distance between a microphone and an earphone is separated, and a user inserts a box-type main body in which an amplifier and a microphone are integrated into a breast pocket or the like, and extends an earphone cord from the box-type main body. A type of hearing aid that uses an earphone inserted into the ear) is also used.

  In addition to the problem that the microphone is integrated with the box-type main body, the box-type hearing aid is separated from the position of the ear and the microphone cannot be placed at an ideal position as described above. It has the following disadvantages.

  The box-type hearing aid is used with the box-type main body in a pocket, etc., but if the box-type main body is put in a pocket, etc., the frequency characteristics of the microphone will change, the high frequency component will decrease, and the intelligibility will decrease. It has the problem of being lowered. Further, when the box-shaped main body is put in a pocket or the like, there is a problem that the sound of cloth slipping accompanying the movement of the body becomes noise.

  On the other hand, in the case of the box-type hearing aid, the microphone cannot be arranged at an ideal position, but has the following merits as compared with the ear-hook type or ear-hole type hearing aid.

  That is, in the case of the above-mentioned box-type hearing aid, since the microphone and the earphone are completely separated, the design can be made considering only the function of the earphone, and the frequency characteristic is set according to the obstacle of the hearing impaired person. It has the merit that it can be easily designed with the acoustic system. In the case of the box type hearing aid, since the amplifier does not need to be extremely small, it is possible to provide a function for adjusting the frequency characteristic electrically in addition to the frequency characteristic determined by the acoustic system of the earphone. It has the advantage of being inexpensive. Furthermore, in the case of the above-mentioned box-type hearing aid, the operation unit such as a switch and a volume is designed to have an appropriate size suitable for operation for use by an elderly person whose fingertips are a little difficult to move. It has the merit that it can be provided.

  Thus, in the case of a conventional ear-hook type or ear-hole type hearing aid or box-type hearing aid, each has advantages and disadvantages, and development of a hearing aid that takes advantage of each advantage is required.

  To explain further, in order to solve the above-mentioned problems and to obtain a hearing aid that can achieve good listening performance, the earphone of the ear type is made small and is integrated with the microphone so that it can be worn in the auricle. A hearing aid is considered.

  As a hearing aid in which a microphone is placed at the position of the ear as described above, for example, those shown in FIGS. 15 and 16 have already been commercialized. The hearing aid 100 shown in FIG. 15 is configured to have a vertically long shape as a whole so that the microphone 101 can be brought closer to the position of the ear hole, and the microphone is arranged outside the auricle to improve the hearing even a little. Is. In addition, the hearing aid 100 shown in FIG. 16 places both the microphone 101 and the earphone at the position of the ear hole, and prioritizes listening to the sound clearly by using the sound collecting function by the pinna 103 of the ear 102. Is.

  However, the conventional technique has the following problems. That is, in the case of the hearing aid 100 shown in FIG. 15, the microphone 101 is brought close to the position of the ear hole to some extent, but the sound leaking outside through the earphone body case is reflected by the auricle, As a result, in order to prevent the sound pressure around the microphone 101 from being increased and facilitating howling, the microphone 101 is disposed outside the pinna 103, and as a result, the sound collecting function by the pinna 103 is obtained. Cannot be used, and the sound cannot be heard clearly.

In the case of the hearing aid 100 shown in FIG. 16, both the microphone 101 and the earphone are disposed at the position of the ear hole, and the sound can be clearly heard using the sound collecting function by the pinna 103 of the ear 102. However, as a hearing aid for highly deaf people, when the amplification gain of the hearing aid is increased, howling occurs and there is a fatal problem that it cannot be applied to highly deaf people.

  The above technical problem will be further described as follows.

  FIG. 17 is an acoustic equivalent circuit showing how the vibration sound of the earphone reaches the microphone in the hearing aid 100 having the structure shown in FIG.

  In FIG. 17, Z1 is directly transmitted to the free space from the components constituting the appearance of the earphone, and impedance when the sound reaches the microphone directly, Z2 is the internal space of the earphone via the internal component of the earphone. From the outer body to the outer body, once transmitted from the outer body to the free space and then directly reaching the microphone body, the impedance when reaching the microphone body directly from the inner space, Z3 is a component constituting the appearance of the earphone It shows the mechanical vibration impedance when transmitted to the microphone body. In FIG. 17, symbol O indicates the mechanical vibration and acoustic vibration of the earphone as signal sources.

  The vibration sound of the earphone is transmitted to the microphone via the impedance of the above three elements. In general, the mass of the microphone is controlled by C2 (low-altitude material), R2, and M2, but if the gain is increased to such a level that a highly-hearing person can use it, howling will occur. Is the current situation.

  In recent years, some DSPs have been used as part of the problem solving means. However, considering the cost and the like, it becomes an expensive product.

  Therefore, the present invention has been made to solve the above-described problems of the prior art, and the object of the present invention is to make use of the advantages of both the ear hole type hearing aid and the box type hearing aid. Even if the microphone and the earphone are both placed at the position and the sound collecting function by the pinna of the ear is used to clearly hear the sound and the amplification gain of the hearing aid is increased, howling An object of the present invention is to provide an earphone with a microphone for a hearing aid that can be prevented from occurring.

In order to solve the above-described problems, the invention described in claim 1 is an ear mounting portion mounted at a position corresponding to the external auditory canal of a human ear, speaker means for converting an electric signal into sound vibration, and the speaker. A microphone means for converting an external sound vibration into an electric signal, the microphone means for converting the external sound vibration into an electric signal, and the electric signal converted by the microphone means. In an earphone with a microphone for hearing aid to be amplified by an amplifier and amplified and converted into sound vibration by the speaker means, the speaker means is attached to the body of the ear wearing part via a vibration isolating member that attenuates the vibration, and as the impedance reducing means for reducing the acoustic impedance of the speaker unit, the diaphragm of the speaker unit The cutout portion communicating the parts and external, a hearing aid microphone earphones, characterized in that a diaphragm support member for supporting the speaker unit.

  The invention described in claim 2 is the earphone with a microphone for hearing aid according to claim 1, wherein the vibration isolating member is made of a viscoelastic body made of a synthetic resin.

  According to the present invention, it is possible to make use of the advantages of both the ear hole type hearing aid and the box type hearing aid, and by arranging both the microphone and the earphone at the position of the ear hole, utilizing the sound collecting function by the pinna of the ear, It is possible to provide an earphone with a hearing aid microphone that can hear sound clearly and can prevent howling even when the amplification gain of the hearing aid is increased.

  Embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1
FIG. 1 is an enlarged view showing an ear mounting portion to be mounted on an ear of a human body of an earphone with a microphone for hearing aid according to Embodiment 1 of the present invention.

  As shown in FIG. 1, the ear mounting portion 1 of the earphone with a microphone for a hearing aid is roughly divided into a housing 2 as an ear mounting portion main body, a speaker member 3 mounted on a distal end portion of the housing 2, and the housing. 2 and a microphone member 4 mounted at a position opposite to the speaker member 3 in FIG. 2, and the ear mounting part 1 is connected to a hearing aid body (not shown) incorporating an amplifier and a power source (not shown) via a cord 5. Has been. The ear mounting portion 1 is configured in the same manner as the left and right ear mounting portions respectively mounted on the left and right ears of the human body. As shown in FIG. 5, the microphone member 4 of the ear mounting portion 1 is disposed on the inner side of the auricle corresponding to the position of the external auditory canal while being mounted on the ear of a human body.

  As shown in FIG. 1, the housing 2 of the ear mounting portion 1 has a hollow interior made of a synthetic resin, and a side surface of the housing 2 is formed in an approximately L shape. In addition, the housing 2 is a first portion that constitutes a front end portion from a portion formed in a short straight line to a portion bent in a substantially L shape in the housing 2 formed in a substantially L shape. The housing 6 and a second housing 7 constituting the base end portion of the housing 2 are configured. The tip portion 6a of the first housing 6 is formed in a substantially cylindrical shape having a relatively large diameter, and the speaker member 3 is attached to the tip 8 of the first housing 6 that is opened in a circular shape. It is attached.

  As shown in FIG. 1, the speaker member 3 holds the speaker unit 9, the vibration isolation member 10 that holds the speaker unit 9, and the speaker unit 9 via the vibration isolation member 10. The speaker lid 11 and the front case 12 that holds the speaker unit 9 in the same manner with the vibration isolating member 10 interposed therebetween. As shown in FIG. 2, the front end portion 11 a of the speaker lid 11 is opened in a large circular shape so as to accommodate the speaker unit 9, and the inner peripheral edge of the front end portion 11 a of the speaker lid 11 is A step portion 13 is formed to sandwich the flange portion 10a protruding from the outer periphery of the vibration isolation member 10. In addition, a large second step portion 14 is provided inside the speaker lid 11 so as to face the vibration isolating member 10 with a minute gap, and further inside the speaker lid 11, It is sealed by a partition wall 16 via a plurality of small step portions 15. Further, the base end portion 11 b of the speaker lid 11 is formed in a cylindrical shape having a smaller diameter than the tip end portion 11 a, and the base end portion 11 b of the speaker lid 11 is the tip end portion 6 a of the first housing 6. It is fixed in a state where it is fitted in. Further, a first substrate 17 for wiring to the speaker unit 9 is fixed to the sealed partition wall 16 of the speaker lid 11 on the surface on the base end side. Furthermore, a lead wire 19 for wiring to the speaker unit 9 is inserted into the partition wall 16 of the speaker lid 11 through a sealing member 20 at a position corresponding to the soldering 18 of the first substrate 17. The leading end of the lead wire 19 is soldered 22 to the substrate 21 of the speaker unit 9.

  On the other hand, the front case 12 is formed in a cylindrical shape in which an end surface 23 on the front end side is closed by a metal such as aluminum and a surface on the base end side is opened, and an intermediate portion of the inner surface of the front case 12 A step portion 24 is formed to sandwich the flange portion 10a protruding from the outer periphery of the vibration isolation member 10. In addition, a large second step portion 25 is provided on the front end side of the front case 12 so as to face the vibration isolation member 10 with a minute gap, and the front end of the inner surface of the front case 12 is also provided. The portion is provided with a shallow concave portion 27 facing the armature 26 of the speaker unit 9 with a minute gap. Further, in order to attach the earplug adapter 28 at the center of the front end portion of the front case 12, a substantially cylindrical mounting portion 29 whose outer periphery is enlarged in a taper shape toward the front end is projected. The base end portion 12a of the front case 12 is bent short inward so as to be locked to a stepped portion 30 provided on the outer periphery of the speaker lid 11.

  An earplug adapter 28 made of a soft synthetic resin such as polypropylene is attached to the attachment portion 29 of the front case 12 and a sponge rubber or the like is attached to the outer periphery of the earplug adapter 28. The earplug 31 which consists of is attached in the state fitted or adhere | attached. In addition, a spiral protrusion 32 is provided on the outer periphery of the earplug adapter 28, and the inner periphery thereof has a two-stage diameter toward the tip portion through a short tapered portion 33 on the way. The insertion holes 34 and 35 are formed so as to be thinner.

  Further, a microphone 4 as a microphone member is disposed in a portion of the housing 2 bent into an L shape, and the microphone 4 is covered with a microphone cover 36 made of a soft synthetic resin or the like. . The microphone 4 is attached in a state of being fitted to the second housing 7 through a thin cylindrical sound hole portion 4 a protruding from the microphone cover 36. Further, a cord 7 made of vinyl chloride resin or its substitute resin, which is fitted and fixed by the second housing 7 and the first housing 6, is attached to the portion 7 a extending in the L shape of the second housing 7. The cord 5 is attached via the bush 37. From the cord 5, a speaker lead wire 38 and a microphone lead wire 39 are drawn out, and the tip of the speaker lead wire 38 is soldered 40 to the first substrate 17. The tip of the lead wire 39 for the microphone is soldered 41 to the back side of the microphone 4.

  FIG. 3 is a sectional view showing the speaker unit.

  The speaker unit 9 is composed of a small magnetic speaker excellent in sound quality, and includes a speaker housing 42 formed in a cylindrical shape with synthetic resin, metal, or the like, as shown in FIG. Inside the speaker housing 42, a cylinder magnetized with a predetermined polarity at a predetermined position via a support plate 42 a projecting from an intermediate portion in the axial direction of the speaker housing 42 toward the inner periphery. A magnet 43 having a shape is arranged. A coil 45 wound around a pole piece 44 is disposed inside the magnet 43. The coil 45 is attached to a plate 46 disposed on the upper surface of the pole piece 44, and the substrate 21 is attached to the plate 46 and is fixed to the speaker housing 42 via a flange 47. . The substrate 21 is connected to the coil 45 through a lead wire 48 soldered 22 and a lead wire (not shown) inserted through a sealing member 49. Further, a diaphragm 50 made of a thin magnetic material is adsorbed to the lower end surface of the speaker housing 42 by the magnetic force of the magnet 43, and a magnetic material such as iron is provided at the center of the lower end surface of the diaphragm 50. A thin disk-shaped armature 26 made of is fixed.

By the way, in the present embodiment, an ear mounting portion mounted at a position corresponding to the external auditory canal of a human ear, speaker means for converting an electric signal into sound vibration, and disposed in the vicinity of the speaker means, Microphone means for converting sound vibration into an electric signal, and converting external sound vibration into an electric signal by the microphone means, amplifying the electric signal converted by the microphone means by an amplifier, and sound by the speaker means In an earphone with a microphone for hearing aid to amplify and convert into vibration, the speaker means is attached to the body of the ear wearing part via a vibration isolating member that attenuates the vibration, and the impedance reduction that lowers the acoustic impedance of the speaker means as a means, a notch communicating the inside and the outside of the diaphragm of the speaker unit And it is configured so as to provide a support member for supporting the diaphragm of the speaker unit.

  Moreover, in this Embodiment, the said vibration isolator is comprised so that it may consist of a viscoelastic body made from a synthetic resin.

  That is, in the ear mounting part 1 of the earphone with microphone for hearing aid according to the present embodiment, the speaker unit 9 is not directly attached to the speaker lid 11 and the front case 12 as shown in FIG. The unit 9 is attached to the speaker lid 11 and the front case 12 via a vibration isolating member 10 that holds the outer periphery of the unit 9 in a fitted state.

  The anti-vibration member 10 is made of, for example, a soft synthetic resin made of sponge such as silicon rubber, and prevents the vibration of the speaker unit 9 from being directly transmitted to the speaker lid 11 and the front case 12. This vibration isolator 10 functionally functions to suspend the speaker unit 9 from the speaker lid 11 and the front case 12, which is merely a method for mechanically controlling the mass, The member 10 may be a thin sheet that holds the speaker unit 9.

  In addition, the vibration isolator 10 is mechanically controlled by the mass of the speaker unit 9, the stiffness and viscoelastic characteristics of the material are important factors, and the hardness and elastic modulus of the material and the speaker unit 9 are controlled. It is desirable to obtain ideal stiffness characteristics by design depending on the structure to be clamped. In the illustrated example, the flange portion 10 a of the vibration-proof member 10 made of a soft material is configured to be clamped (sandwiched) by the speaker lid 11 and the front case 12. Further, it may be desirable to set a certain clearance so that the vibration of the speaker unit 9 itself is not directly transmitted to the housing 2 and the front case 12.

  Further, if the lead wire 19 that is electrically connected to the speaker unit 9 has such a high hardness as to change the stiffness characteristics of the vibration isolating member 10, the speaker via the lead wire 19 is used. This is not desirable because the unit 9 itself is fixed. Furthermore, since the lead wire 19 itself is directly electrically connected to the speaker unit 9 that is the vibration source, it is considered that vibration is directly transmitted to a slight extent. Therefore, it is desirable to fix the lead wire 19 to the inside of the housing 2 so as not to contact the macrophone cover 4a or the like.

Further, as shown in FIG. 3, the speaker unit 9 is provided with impedance lowering means 51 for lowering the acoustic impedance of the speaker unit 9. As shown in FIG. 3 , the impedance lowering means 51 includes a notch 52 that communicates the inside and the outside of the diaphragm 50 of the speaker unit 9, and the notch 52 is a vibration of the speaker unit 9. The speaker housing 42 is provided as a support member that supports the plate 50. Moreover, the front-end | tip part 52a of the said notch 52 is notched in the taper shape.

  As a result, since the speaker unit 9 is provided with the notch 52 in the speaker housing 42, the speaker unit 9 is configured so that the acoustic impedance, particularly in the low frequency range, is lowered. As the acoustic impedance decreases, the mechanical vibration impedance also decreases as a result.

  FIG. 4 shows an acoustic equivalent circuit of the speaker unit 9.

  As understood from this figure, the speaker unit 9 is provided with a notch 52 in the speaker housing 42, so that the signal of the speaker unit 9 (generated by the vibration of the diaphragm of the speaker unit 9) is generated. Secondary signal) The acoustic inductance M3 and the resistor R3 connected in series to the element 55 are connected in parallel, and the acoustic impedance of the speaker unit 9 decreases. Yes. Since the acoustic impedance of the speaker unit 9 varies depending on the shape, position, number, etc. of the notches 51, the desired acoustic impedance characteristics can be obtained by appropriately designing the shape, position, number, etc. of these notches 51. Can be obtained.

  In the above configuration, the earphone with a microphone for hearing aid according to the present embodiment can take advantage of both the ear hole type hearing aid and the box type hearing aid as follows, and the microphone and the earphone at the position of the ear hole. Both can be placed and the sound collection function by the pinna of the ear can be used to hear the sound clearly, and even when the amplification gain of the hearing aid is increased, howling is prevented. It is possible.

  That is, as shown in FIG. 5, the earphone with a hearing aid microphone according to the present embodiment is mounted with the ear mounting part 1 in a state where the earplug 31 is inserted into the external auditory canal of the human ear 60. The sound hole portion 62 of the microphone member 4 of the portion 1 is arranged inside the auricle 61 corresponding to the position of the external auditory canal in a state where the ear mounting portion 1 is mounted on the ear 60 of the human body.

  In the earphone with a microphone for a hearing aid, as shown in FIG. 1, the sound vibration is heard by the microphone member 4 and converted into an electric signal. The electric signal converted by the microphone member 4 includes the microphone lead wire 39 and Via the cord 5, it is sent to an amplifier built in the hearing aid body (not shown). The electric signal amplified by this amplifier is sent to the speaker unit 9 via the cord 5 and the speaker lead wire 38, and is converted into sound vibration in a state amplified by the speaker unit 9, and used by the deaf person, etc. Listened to by a person. At that time, in the above-mentioned hearing aid, the amplification gain of the amplifier can be set high, so that it can be used even for highly deaf people.

  FIG. 6 shows the effect of reducing both the mechanical vibration impedance and the acoustic impedance of the speaker unit 9 confirmed by experiments. The confirmation experiments 1 and 2 are performed by inputting a 1 mW electrical signal to the speaker unit 9 using the ear mounting portion of the earphone with a hearing aid microphone before taking the measures of the present invention, and the speaker unit 9 received by the microphone 4. Measured sound from

  The condition of Confirmation 1 shown in FIG. 6A is measured in a state where the tip opening of the earplug 31 is filled with clay. However, what kind of sound the microphone 4 receives from the speaker unit 9 was measured around the product being measured under the condition that the sound pressure around the microphone 4 did not increase due to sound reflection. Is.

  The condition of Confirmation 2 shown in FIG. 6B is to determine what sound the microphone 4 receives from the speaker unit 9 when the product is actually mounted on the ears 60 of the dummy doll (mounted state). It is measured.

  Under the condition that no sound leaks from the ear canal of the wearer's ear, as can be seen from the comparison of the characteristics of the confirmations 1 and 2, when the microphone 4 is actually arranged inside the auricle 61, the microphone 4 is about 10 dB depending on the frequency. It can be seen that the sound of the speaker unit 9 is received. In addition, it was found that when the electrical amplification of the hearing aid was increased to 25 dB or more under the condition of Confirmation 2, howling occurred in the mounted state, and it was not usable for highly deaf people.

  FIGS. 7 (a) and 7 (b) show the results of confirmation experiments 3 and 4 performed by the inventor using the ear wearing part 1 in which the measures for preventing howling of the present invention were taken under the same conditions as the confirmation experiments 1 and 2 described above. Is shown. Confirmation Experiment 3 was performed under the same conditions as Confirmation Experiment 1, and Confirmation Experiment 4 was performed under the same conditions as Confirmation Experiment 2.

  In comparison between the above confirmation experiments 3 and 4, in confirmation 4 (mounted state), the microphone 4 gradually becomes more susceptible to the sound of the speaker unit 9 from about 3 kHz or higher, but compared with the above confirmation experiments 1 and 2. It can be seen that there is no particularly resonating part, it is very stable, and howling can be prevented. In addition, at a frequency of 10 kHz or more, since the half wavelength of the sound approaches the size of the internal shape of the auricle 61, the sensitivity received by the microphone 4 increases, but the frequency of 10 kHz or more electrically or acoustically. It is sufficient to adopt a structure that attenuates. Note that the above data was measured without a high-cut filter that cuts off particularly high frequency components.

  Further, in the state of confirmation experiment 4, it was confirmed that no howling would occur at all even if an earphone with a microphone for hearing aid was actually attached and amplified with a gain of 36 dB or more.

  Next, the inventor conducted an experiment for confirming the acoustic frequency characteristics of the speaker unit 9 of the ear mounting portion 1.

  The frequency characteristic shown in FIG. 8 shows the earphone with a hearing aid microphone before the countermeasure of the present invention is taken, and the frequency characteristic shown in FIG. 9 shows the earphone with a hearing aid microphone with the countermeasure of the present invention taken. FIG. 9 is a frequency characteristic in which an acoustic inductance M3 and a resistor R3 are arranged as shown in FIGS. 1 and 4, and a force converted from an electrical signal to mechanical vibration is connected in parallel to M3 and R3. This shows that the vibration between the low frequency (20 to about 100 Hz) is attenuated. It has been found that there is no problem in practical use for the attenuation in this frequency range.

  If the impedances of M3 and R3 are drastically lowered, the sensitivity of the frequency band to be originally output is affected. Therefore, it is necessary to design with sufficient consideration. A frequency characteristic 4 shown in FIG. 11 is a characteristic in which M3 and R3 are not arranged in the structure shown in FIG. 1, and the frequency characteristic 3 shown in FIG. 10 is a measurement result of the same structure as that of the present invention shown in FIG. As understood from the frequency characteristics, a high frequency of 1 kHz or more is obtained by using a structure in which the mass of the speaker unit 9 is mechanically controlled by the vibration isolating member 10 and a structure in which the low frequency is cut acoustically. It can be confirmed that the peaks and valleys of resonance are small. Usually, this valley (generated by the phase inversion of resonance) is acoustically designed inside the speaker unit 9, but the mechanical mass control of the speaker unit 9 itself and the acoustic output of M3 and R3 are acoustic. It is understood from the characteristic that it is a damper. The earplug 31 is ideally formed by molding a high-density foamed urethane resin that has good adhesion to the ear canal.

  Furthermore, the inventor conducted an experiment to compare the acoustic frequency characteristics of the hearing aid microphone-equipped earphone according to the present embodiment with the acoustic frequency characteristics of the conventional product. In FIG. 12, the thick line represents the acoustic frequency characteristic of the earphone with microphone for hearing aid according to the present embodiment, and the thin line represents the acoustic frequency characteristic of the conventional product (shown in FIG. 16). As is clear from FIG. 12, the conventional product has a microphone arranged at a preferred position inside the auricle, but the sensitivity cannot be increased because howling is likely to occur. In the frequency band indicated by →, the sensitivity is the same as that of the earphone with a hearing aid microphone according to the present embodiment, but otherwise the sensitivity is generally poor.

  Furthermore, in order to show how the conventional product is likely to cause howling compared to the earphone with a microphone for hearing aid according to the present embodiment, the present inventor is the same as the confirmation experiments 1 and 2 described above. It was measured what kind of sound the microphone 4 received from the speaker unit 9 under the following conditions. FIG. 13 shows the result of measurement under the same conditions as in the confirmation experiment 1, FIG. 14 shows the result of measurement under the same conditions as in the confirmation experiment 2, the solid line is based on the measurement result itself, and the chain line is based on the frequency characteristic. The corrected measurement result is shown.

  Whether or not howling is easy depends on how much sound the microphone receives from the speaker unit. As is apparent from FIGS. 13 and 14, the conventional product is indicated by ← → at the bottom of the figure. It is understood that the sensitivity of the microphone is significantly increased in the frequency band, and howling is likely to occur. On the other hand, as is clear from FIG. 7 showing the results of measurement under the same conditions, the earphone with a microphone for hearing aid according to the present embodiment has no peak in the sensitivity of the microphone as in the conventional product, and howling occurs. It is suppressed.

  As described above, the present invention can make use of the advantages of both the ear hole type hearing aid and the box type hearing aid, and arranges both the microphone and the earphone at the position of the ear hole and utilizes the sound collecting function by the pinna of the ear. Thus, it is possible to provide an earphone with a hearing aid microphone that can clearly hear sound and can prevent howling even when the amplification gain of the hearing aid is increased.

  As described above, the present invention provides a hearing aid microphone that can clearly hear sound and does not generate howling even if the amplification gain of the hearing aid is increased as a hearing aid for highly deaf people.

It is sectional drawing of the earphone with a microphone for hearing aids which concerns on an example of implementation of this invention. It is sectional drawing which shows the accommodation state of the speaker unit in the earphone with a microphone for hearing aids which concerns on an example of implementation of this invention. It is sectional drawing which shows the speaker unit in the earphone with a microphone for hearing aids which concerns on an example of implementation of this invention. It is an equivalent circuit diagram of the earphone with a microphone for a hearing aid according to an example of the embodiment of the present invention. It is a perspective view which shows the mounting state of the earphone with a microphone for hearing aids which concerns on an example of implementation of this invention. It is a graph which shows the sensitivity of the microphone in the earphone with the microphone for hearing aids which does not employ | adopt the structure of this invention. It is a graph which shows the sensitivity of the microphone in the earphone with the microphone for hearing aids which concerns on an example of implementation of this invention. It is a graph which shows the frequency characteristic of the microphone in the earphone with the microphone for hearing aids which does not employ | adopt the structure of this invention. It is a graph which shows the frequency characteristic of the microphone in the earphone with the microphone for hearing aids which employ | adopted a part of structure of this invention. It is a graph which shows the frequency characteristic of the microphone in the earphone with the microphone for hearing aids which concerns on an example of implementation of this invention. It is a graph which shows the frequency characteristic of the microphone in the earphone with the microphone for hearing aids which employ | adopted a part of structure of this invention. It is a graph which shows the frequency characteristic of the earphone with the microphone for hearing aids which concerns on an example of implementation of this invention, and a conventional product. It is a graph which shows the sensitivity of the microphone in a conventional product. It is a graph which shows the sensitivity of the microphone in a conventional product. It is a perspective view which shows the mounting state of the conventional product. It is a perspective view which shows the mounting state of the conventional product. It is an equivalent circuit diagram of a conventional product.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ear mounting part of earphone with microphone for hearing aid 2 Housing 3 Speaker member 4 Microphone member 5 Code 5
6 First housing 7 Second housing 9 Speaker unit 10 Anti-vibration member

Claims (2)

An ear mounting portion mounted at a position corresponding to the external auditory canal of a human ear, speaker means for converting an electric signal into sound vibration, and disposed in the vicinity of the speaker means to convert external sound vibration into an electric signal. Hearing aid for converting external sound vibration into an electric signal by the microphone means, amplifying the electric signal converted by the microphone means by an amplifier, and amplifying and converting the sound signal by the speaker means In the earphone with microphone, the speaker means is attached to the body of the ear mounting portion via a vibration isolating member that attenuates the vibration, and the vibration of the speaker means is used as an impedance lowering means for reducing the acoustic impedance of the speaker means. A notch communicating the inside and the outside of the plate is provided with a vibration of the speaker means. Hearing aid microphone earphones, characterized in that provided on the support member for supporting the plate.   The earphone with a microphone for a hearing aid according to claim 1, wherein the vibration isolating member is made of a viscoelastic body made of a synthetic resin.