JP6421360B2 - Inner earphone - Google Patents

Description

The present invention relates to an earphone that can prevent a hearing loss due to ear fatigue by listening to sound and can change sound quality.

For example, Patent Document 1 discloses a structure in which a vibrating body composed of a laminated piezoelectric actuator element or a laminated bimorph vibrator is embedded in a rod-shaped member 13 formed of a resin such as silicon rubber or urethane rubber inserted into the ear canal. The earphone that functions as an earplug when inserted into the ear canal, guides sound waves to the eardrum by vibration of the rod-like member, and transmits the vibration of the rod-like member as bone transmission through the cartilage near the inner wall of the ear canal Is disclosed.

However, this earphone is limited in vibration because the vibrator is embedded in the resin, and an elastic body having a sound absorbing action is interposed as bone conduction, so that acoustic conversion efficiency and transmission efficiency are poor. There were disadvantages.

Patent Document 2 discloses an earphone that corresponds to the rod-shaped member of Patent Document 1 and has a configuration similar to that of Patent Document 1 provided with a through-hole in the center. Although it is a structure which can hear an external sound through a hole, since the structure is the same as that of Patent Document 1, the sound conversion efficiency is poor and the sound quality cannot be varied according to preference.

Patent Document 3 includes an ear pad, a part of which is inserted into the ear canal, a cylindrical tubular body, an extension portion integrally provided on the tubular body, and a piezoelectric element attached to the extension portion for transmission. A member is formed, and a hole penetrating the ear pad and the cylindrical body is provided so that an external sound can be heard. Sound vibration is transmitted to the eardrum with the ear pad, and the tragus is brought into contact with the tragus with the transmission member. A device that attempts to transmit sound also by cartilage vibration via a cable is disclosed.

However, what is disclosed in this Patent Document 3 is to mainly transmit the reproduced sound by contacting with the tragus, and in which the ear pad 3 made of an elastically deformable member and the vibrating portion 6 are inserted into the ear canal However, since the entire piezoelectric element is attached to the extending portion 2a, the conversion efficiency is poor, and the sound quality cannot be changed other than changing the entire material.

JP 2009-232443 Japanese Patent Laid-Open No. 2014-107828 Japanese Unexamined Patent Publication No. 2014-146949

The earphones described in Patent Documents 1 and 2 are mainly cartilage vibration sound reproduction for the ear canal because the vibrating body is arranged in parallel with the ear canal on the member inserted into the ear canal, and vibration Since the child is embedded in the resin, the vibration is limited, and since the elastic body has a sound absorbing action as bone conduction, there are drawbacks such as poor acoustic conversion efficiency and transmission efficiency, and the structure The sound quality could not be changed according to taste.

In addition, what is disclosed in Patent Document 3 is intended to transmit sound also by cartilage vibration through the tragus by contacting the tragus with a sound signal by air propagation and a transmission member. Since the entire element is affixed to the extending portion 2a, the acoustic conversion efficiency is poor, and the sound quality cannot be varied structurally according to preference.

Also, most high-quality earphones called hi-fi use a magnetic circuit to vibrate a diaphragm with an electrical signal and send sound waves to the ear canal, thereby vibrating the eardrum with sound waves. For this reason, in the conventional earphone, a sound source is always present at the ear, and a strong sound pressure is applied to the eardrum.

In this case, the sound pressure level may reach from 90 dB to 100 dB, and this sound pressure level is the same level as when the train passing sound is heard under the card.
Therefore, these earphones have problems such as ear fatigue when listened to for a long time, and when hearing at a high volume, the function of the ear is damaged, resulting in hearing loss. In order not to return to the original state, it was a big social problem that young people who often listen to music with earphones became deaf.

In order to eliminate the drawbacks of the conventional earphones, bone conduction and cartilage conduction as shown in Patent Documents 1 to 3 are provided, but there are few acoustically satisfactory, and wide-band reproduction, that is, high-quality sound reproduction. There was a fault such as not suitable for.

The present invention realizes a high sound quality earphone that is hard to be tired even after listening for a long time and is difficult to use with a bone conduction (cartilage conduction) type earphone while using bone conduction using a piezoelectric element, and an earphone that is hard to be deaf. A cylindrical case with an L-shaped outer shape, a flat plate-like vibrator that is fixed to one end of the case and arranged in a cantilever shape toward the inside of the case, and the other of the case A vibrator that is inserted so that a part projects from the end, and the other end is integrally joined to the free end of the vibrator inside the case, and a signal line that supplies an electrical signal to the vibrator An inner earphone characterized by comprising:

In the inner ear type earphone of the present invention, the vibrator is fixed to the end of the case in a cantilever shape, and the circumference of the vibrator is arranged in a space in the pipe-like case so that vibration is not transmitted to the case. By allowing energy to be transmitted to the vibrating body, the vibration that is attenuated by being transmitted to the case is reduced, and the free end of the vibrator transmits vibration to the ear in the case of the vibrating body. By attaching to the end, it is possible to increase the range in which the vibrator vibrates, which has the effect of increasing the vibration efficiency and the electroacoustic conversion efficiency.

In addition, in the earphone of the present invention, vibration efficiency and the like can be increased as compared with conventional bone conduction, and in addition to bone conduction, air vibration can be generated by the vibrating body. Since it becomes larger than the above, while suppressing the sound waves generated from the vibrating body to some extent, the advantages of the bone conduction headphones are “the ear hole does not hurt”, “the eardrum is not burdened”, “impact sound and surrounding noise are not worried” By utilizing the characteristics of bone conduction (cartilage conduction), such as “I can hear the surrounding sounds as usual” and “I can hear them well”, the sound pressure directly applied to the eardrum even when inserted into the ear canal Since the regenerative sound transmitted to the listener by bone conduction from the external auditory canal is about 70%, the sound pressure that directly transmits vibration to the eardrum is reduced, and the burden on the eardrum is reduced, so that the inner ear is not tired. It is those that can provide the phone.

Furthermore, in the earphone of the present invention, as described above, the vibrator is fixed to the end of the case in a cantilever shape, and its free end is attached to the end of a vibrating body that generates sound, thereby increasing the vibration range of the vibrator. By adopting a configuration that can generate not only conventional bone conduction but also air vibration with a vibrating body, it is a drawback of bone conduction that “requires greater drive power than earphones” “large volume is obtained It is possible to improve the disadvantages such as “unusable”, “not suitable for reproduction of wideband sound”, “difficult to hear for hearing-impaired hearing person”, “however, hearing aid tends to cause howling with hearing aid”.

In addition, in the present invention, the vibrating body is configured so that materials having different transfer coefficients and natural frequencies can be exchanged, and the sound is transmitted to the ear through these exchangeable members, so that the reproduced sound can be selected by selecting the material. The sound quality can be changed to a desired one.

Furthermore, by providing an earplug-like soundproofing material at a position that comes around the end of the ear canal when inserted into the ear canal, the external noise is blocked by closing the entrance of the ear canal with a soundproofing material. It is designed to allow listening in the absence of noise.

Further, in the present invention, since all parts of the earphone can be composed of a non-magnetic material, it can be used in a place where a magnetic material such as an MRI cannot be used.

BRIEF DESCRIPTION OF THE DRAWINGS The inner earphone of this invention is shown, (a) is a front view, (b) is a side view, (c) is AB sectional drawing shown to a front view. 1 is a cross-sectional view of the inner earphone of the present invention, which is a modification of FIG. In another embodiment of the inner earphone of the present invention, (a) is a front view, (b) is a side view, (c) is a cross-sectional view taken along line AB of (a), and (d) is a C- It is D sectional drawing. FIG. 3 is a cross-sectional view illustrating the embodiment of the present invention shown in FIG. It is a further embodiment of the present invention. The shape of the soundproof material of this invention is shown. It is a figure which shows the concept of the use condition of this invention. It is a figure which shows the conventional earphone.

Embodiments of an inner earphone of the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the following examples.
FIG. 1 is a first embodiment showing a basic form in an embodiment of the inner earphone of the present invention, (a) is a front view, (b) is a side view, and (c) is a cross-sectional view taken along line AB shown in the front view. It is.
The case 1 is a cylindrical pipe having an L-shaped cross section, and one is formed thinner than the other.
2 is a vibrator composed of a piezoelectric bimorph element, a piezoelectric actuator element, etc., one end is fixed to one end of the thin case and the other end is arranged so that the case 1 does not contact the internal space 1a of the case 1 Thus, the release end is configured to be able to vibrate freely like a cantilever. A cylindrical vibrating body 3 is inserted into the other end portion of the case 1, and the end portion is coupled to the vibrating body 2 in the case.

As for the coupling of vibrator 3 and vibrator 2, the actual effect is the same whether it is simply glued with an adhesive or a vibrator is inserted with a groove or the like provided at the end of the vibrator. In this case, it is desirable that a groove is provided at the end of the vibrating body, and the end of the vibrator is inserted before bonding.

4 is a silicon tube that is integrally covered with the vibrating body 3 and prevents the earphone from coming out when it is inserted into the ear canal, and also protects the ear from damage to the ear canal as it is inserted into the ear canal. It is important in terms of sound quality because it absorbs high-frequency white noise that is acoustically noise. Reference numeral 5 denotes a lead wire for supplying a signal to the vibrator. One end of the lead wire is electrically coupled to the vibrator 2, and an electric signal such as music is supplied to the vibrator 2 from a known acoustic device. The vicinity of the connection between the lead wire 5 and the vibrator 2 is fixed in a state where it is acoustically shielded from the case 1 so that the vibration of the case is not transmitted to the vibrator 2 by a fixing member 7 made of a sound absorbing material such as urethane. It is what is done.
The vibrating body 3 inserted into the case 1 is not a strong fit and is configured to vibrate without falling off.

In such a configuration, when an electric signal is supplied to the vibrator 2, the vibrator 2 vibrates according to the electric signal, and vibrates the vibrating body 3 to which the end portion is coupled.
In this embodiment, when the vibrating body 3 is inserted into the ear canal, the vibration body 3 comes into contact with the ear canal 9 as shown in FIG. In addition to being transmitted to the auditory organ by bone conduction (cartilage conduction), the vibration of air generated by the vibration of the vibrating body 3 is transmitted to the eardrum, and is heard by the listener as sound by air vibration and bone conduction (cartilage conduction). is there.

In the present invention, the vibration of the vibrating body 3 is small due to the volume and mass of the vibrating body 3 being larger than that of the vibrator 2, but the vibration of the vibrating body 2 can be heard as bone conduction. It is possible to provide an earphone that has little sound pressure applied to the eardrum and that requires very little fatigue and that does not get tired even when used for a long time.

Further, in the present invention, one end of the vibrator 2 is fixed in the vicinity of the end of the case 1, and a cantilever structure other than the fixed portion is positioned in the space, and the end of the vibrator 3 is coupled to the free end, The vibration energy of the vibrator 2 can be effectively used, and an electric signal can be efficiently converted into an audio signal.

In FIG. 2, a damper 6 made of an elastic body is inserted between the vibrating body 3 and the case 1 in order to easily vibrate the vibrating body 3 of the embodiment shown in FIG. Although the damper 6 shown in the figure has a square cross section, it is of course possible to use a damper having a donut-shaped cross section. By changing the shape and number of the dampers 6 as appropriate, the vibration state of the vibrating body 3 changes, and the characteristics of signal transmission due to bone conduction and air vibration can be varied, as well as the sound quality and playback efficiency. It can be made to.

FIG. 3 shows a second embodiment which is an advanced form of the present invention, which shows the sound quality of the earphone that can be changed according to preference, and is the same as FIG. 1 and FIG. Portions are denoted by the same numbers and description thereof is omitted.

In this embodiment, the vibrator shown in FIG. 1 and FIG. 2 is structured to be separated into two parts 3a and 3b, the part coupled to the vibrator 2 is a vibration holder 3b, and the vibrator 2 and A concave portion 33 is provided at an end portion on the non-coupled side, and a female screw 34 is provided on the inner side to constitute a fixing means.
On the other hand, the female screw 34 has a vibration member exchanging portion 3a having a male screw 35, which is fixed to the vibration holder 3b by a screw so as to be exchangeable as a sound quality adjusting member. FIG. 4 shows a state before the vibration holder 3b of the vibrating body and the exchanging portion 3a as the sound quality adjusting body are coupled.

Further, the end 2a of the vibrator 2 is fixed near one end of the case 1 by the fixing member 7, and the free end of the vibrating body 2 extending from the fixing member 7 to the inside of the case is positioned in the space in the case 1. It is arranged so that it does not come into contact with the case 1, and is fixed in a cantilever shape so that the vibrating body 2 can vibrate freely when given an electric signal.

FIG. 5 shows still another embodiment of the embodiment shown in FIGS. 3 and 4, as shown in (a) to (d) of FIG. It shows the state that the sound quality can be changed by changing the length and exchanging it, and the thickness and length of the replacement part 3a of the vibrating body according to the difference in the ear structure of the listener who uses the earphone By changing the shape, it is possible to use an optimum shape suitable for each listener's ear.

Furthermore, even if the replacement part 3a has the same shape, each material possesses by being composed of different materials such as plastics such as acrylic materials, wood made of balsa materials, etc., paper, metals such as aluminum, etc. The sound quality of the reproduced sound can be changed by the inherent transmission coefficient and frequency characteristic, and a sound quality adjusting body that can change the sound quality according to the listener's preference is configured.

The material used for the exchange part 3a is a soft sound for wood, a sound for metal that is characterized by hard high frequencies, and a plastic that has characteristics different from those for middle and low frequencies. It is also possible to change by.
FIG. 5 (d) shows that the sound can be changed depending on the shape even with the same material, and the hole 3c is provided so that the center of the exchange part 3a which is a sound quality adjusting body is cylindrical, and the exchange part 3a. Since the end inserted into the outer ear becomes hollow and becomes a pipe shape, the resonance moves to the outer periphery and the vibration level of bone conduction is further increased, so that the sound quality is also changed.

6 shows a so-called soundproof body 8 in the form of a donut that is attached to the outer periphery of the replacement part 3a, which is a sound quality adjusting body of the vibrating body 3, for the purpose of blocking external sound during listening. When the inner earphone of the present invention is inserted into the ear as shown in FIG. 7, the soundproofing body 8 is inserted into the earphone as shown in FIG. The external noise that enters the external auditory canal 9 when listening to the earphone is reduced and the music can be enjoyed in a quiet state.

In particular, when a person who is examined by MRI or the like listens to music or a doctor's instructions through earphones, very loud noise generated by MRI can be blocked by soundproofing material 8, and by wearing this soundproofing material 8 In addition, music and instructions can be heard clearly even in an environment where external noise is intense. In addition, since the passing frequency of the soundproofing material 8 varies depending on the material, it is possible to cut off the external sound most effectively by selecting the material of the soundproofing material 8 for the noise that is cut off according to the frequency distribution of the external noise. Is.

Furthermore, since the earphone of the present invention can be listened to by bone conduction, it can of course be used not only in the air but also in the water.

1 Case 2 Vibrator 3 Vibrating body 3a Replacement part (sound quality adjusting body)
3b Vibration holder 4 Silicon tube 5 Lead wire 6 Damper 7 Fixing member 8 Soundproof material 9 External auditory canal

Claims (10)

  An L-shaped cylindrical case, a flat plate-like vibrator having one end fixed to one end of the case and arranged in a cantilever shape toward the inside of the case, and a part from the other end of the case The vibrator is inserted so as to protrude and the other end is integrally formed with the free end of the vibrator inside the case and a signal line for supplying an electric signal to the vibrator. Inner earphone characterized by. The inner earphone according to claim 1, wherein a portion protruding from the case of the vibrating body is covered with an elastic silicon tube. An L-shaped cylindrical case, a flat-plate vibrator having one end fixed to one end of the case and configured in a cantilever shape toward the inside of the case, and a case inserted into the other end of the case A vibration holder in which a concave portion is formed toward the outer side, the screw fixing means is provided in the concave portion, and the other end is integrally joined to the free end of the vibrator inside the case, and the vibration holder In the inner earphone having a sound quality adjusting body that is replaceably attached to the fixing means and a signal line that supplies an electric signal to the vibrator, the vibrating body is formed by the vibration holder and the sound quality adjusting body. Inner earphone to play. 4. The inner earphone according to claim 1 , wherein a vibration holder fixing member made of an elastic body is interposed between the vibration holder and the case. The inner earphone according to claim 3, wherein the sound quality adjusting body is made of a material of wood, metal, glass, or plastic so that the sound quality can be selected.   The inner earphone according to claim 3, wherein the outside of the sound quality adjusting body is covered with a silicon tube.   4. The inner earphone according to claim 3, wherein a soundproofing material made of a sound absorbing material, which is formed in a donut shape by a sound absorbing material on the outer periphery of the sound quality adjusting body and configured to block external sound, is mounted.   The inner earphone according to claim 3, wherein a plurality of sound quality adjusting bodies having different outer shapes are prepared and can be changed in accordance with the inner diameter of the ear canal of the user's ear.   9. The inner earphone according to claim 8, wherein a concave portion is provided in the direction of the vibrator from an end portion of the sound quality adjusting body on the side inserted into the ear. The inner earphone according to claim 1 , wherein a space is provided between the vibrator and the case.

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