JP2009077116A - Bone conduction handset device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve transmission performance in a noisy environment and to reduce echo back. <P>SOLUTION: The bone conduction handset device 1 includes: a bone conduction speaker for reception which converts sound information to mechanical vibrations; a directional microphone 6 having a high sensitivity in a specific direction; and housings (11 and 12) having a least the directional microphone 6 stored therein. Cylindrical ribs (11c and 12b) for holding the directional microphone 6 are provided on inside walls of the housings (11c and 12b). The cylindrical ribs (11c and 12b) are formed so as to partition a space into a storage space 21 for storing the directional microphone 6 and a flip inner space 22 and have a rigidity equal to or higher than that of the housings (11 and 12). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a bone conduction transmitter / receiver including a bone conduction speaker that converts sound information such as voice and music into mechanical vibration and a directional microphone that is highly sensitive to a specific direction.

  Humans sense “sound” indirectly not only by “sound” coming directly into both ears but also by vibrations transmitted through the body. One of devices that transmit “sound” to a user using such a property is a bone conduction speaker. The bone conduction speaker is a conversion device that converts sound information into mechanical vibration and transmits the vibration to the human head. This mechanical vibration is transmitted to the auditory organ (cochlea) via the skull and is perceived as “sound”. This bone conduction speaker can transmit "sound" to people with disabilities in the sound transmission parts such as the outer ear and inner ear, and it is easy to hear "sound" even in noisy environments. It has the advantage of becoming.

  There has been proposed a bone conduction transmitter / receiver such as a cellular phone including such a bone conduction speaker (see, for example, Patent Documents 1 and 2). By using such a bone conduction transmission / reception device, it becomes possible to accurately hear sound information from the other party even in a noisy environment, and the reception can be ensured. However, picking up the sound spoken by the user in a noisy environment with a microphone and transmitting it to the other party, that is, transmitting the microphone, the microphone picks up the surrounding noise. It is still difficult to hear.

Therefore, a method has been proposed for improving the transmission state in a noisy environment by using a directional microphone having high sensitivity to sound waves in a specific direction as a microphone for transmission (see, for example, Patent Document 3). ). The directional microphone is less likely to pick up ambient noise due to its directivity and relatively picks up the user's voice, so that the communication partner can easily hear the user's voice.
JP 2003-348208 A JP 2000-341778 A Japanese Patent Laid-Open No. 10-290491

  As described above, when a directional microphone is used as a microphone of a mobile phone, at least ambient noise included in the voice transmitted to the other party can be reduced, and the user can comfortably transmit and receive the speech. However, when a bone conduction speaker is used as a receiving speaker, there arises a disadvantage that is different from that of a normal mobile phone.

  Compared to general air-conducting speakers, the bone conduction speaker has mechanical vibrations transmitted to the housing that are orders of magnitude greater, and the mechanical vibration is also transmitted to the periphery of the microphone in the housing. When the microphone picks up the mechanical vibration of the casing and the sound wave generated by the vibration as “sound”, a phenomenon occurs in which the sound information sent from the call partner returns to the speaker of the call partner as it is. Such a phenomenon is called echo back.

  Various proposals have conventionally been made to reduce echo back. For example, by using a soft vibration-proof structure as a microphone holding member and minimizing the contact surface (holding surface) between the structure and the microphone, the mechanical vibration transmitted to the directional microphone is reduced. The structure to be used is adopted.

  However, as described above, the echo back is generated not only by the mechanical vibration directly transmitted to the microphone, but also by a sound wave generated inside the housing by vibrating the surrounding housing. As a result of intensive studies by the inventor, it has been found that the sensitivity of the microphone to the sound wave generated inside the housing is much higher than the sensitivity to the mechanical vibration transmitted directly. In the above support structure using a soft vibration-proof structure and the holding surface as small as possible, high-frequency mechanical vibrations are not directly transmitted to the microphone, but the confidentiality of the microphone's sound collecting part is not high. The generated sound wave goes around the sound collection surface of the microphone, and the microphone picks up the sound.

  Furthermore, if the microphone is held by a soft vibration-proof structure, the distance between the microphone's sound collection surface and the inner wall of the housing with a small space is relatively close to the mechanical vibration from the bone conduction speaker. In order to change, the sound pressure changes in the space on the sound collection surface of the microphone, and sound waves are generated. Therefore, if a soft vibration-proof structure is adopted, the sound wave generated by the vibration of the bone conduction speaker becomes large, and it becomes easy to pick up the sound with the microphone.

  The present invention has been made in view of such a problem, and realizes improvement of transmission performance in a noisy environment and reduction of echo back due to mechanical vibration of a bone conduction speaker, and comfortable transmission / reception. It is an object of the present invention to provide a bone conduction transducer.

  A bone conduction transmitting / receiving apparatus according to the present invention includes a bone conduction speaker for receiving voice information that converts sound information into mechanical vibration, a directional microphone provided with a sound collection surface having sound collection holes on both sides, and at least the directional signal. A bone conduction transmitter / receiver comprising a housing for storing a directional microphone, wherein a structure for holding the directional microphone is provided on an inner wall of the housing, and the structure is provided in the housing, It is formed so as to partition a storage space in which the directional microphone is stored and another space, and has rigidity equal to or higher than that of the casing.

  In this way, if a directional microphone is used as a microphone for transmission, the user's voice is strongly picked up, and it becomes difficult to pick up surrounding noise, so that the transmission performance in a noisy environment can be improved. Become. Since the directional microphone is held in a structure having rigidity equal to or higher than that of the housing, the variation in the distance from the inner wall of the housing is reduced, and the directional microphone is stored by mechanical vibration of the bone conduction speaker. Generation of sound waves in the space is suppressed. Furthermore, since the microphone storage space is separated from other spaces within the enclosure by the structure, the sound waves generated in the other spaces are not transmitted to the microphone storage space. become. Therefore, by using the bone conduction transmitter / receiver of the present invention, it is possible to improve the transmission performance in a noise environment and reduce echo back due to the mechanical vibration of the bone conduction speaker, which is comfortable in the noise environment. You will be able to send and receive calls.

  Further, the storage space is formed by the two inner walls facing the housing and the structure, and the directional microphones are stored in the storage space in a state where the directional microphone is stored in the storage space. Two small spaces facing the sound surface are formed, and the two small spaces can be made small enough not to block the sound collection hole of the directional microphone.

  In the directional microphone, the sound collecting surfaces are provided on both surfaces, and the directivity characteristics are obtained by the differential of the sound collecting results of both sound collecting surfaces. Therefore, when a directional microphone is used as a microphone for transmitting, the support structure of the microphone can be used to suppress the generation of sound waves due to the mechanical vibration of the bone conduction speaker and The structure must be able to collect sound. When the directional microphone is stored in the storage space, two small spaces facing each sound collecting surface of the directional microphone are formed in the storage space. When the small space is as small as possible, the relative fluctuation in the distance between the sound collection surface and the inner wall of the housing is reduced, so that the generation of sound waves in the storage space of the directional microphone due to the mechanical vibration of the bone conduction speaker is suppressed. I found out. However, if the sound collection hole of the directional microphone is blocked in the two small spaces, the directivity of the directional microphone is reduced. The size was such that it could not be blocked.

  Furthermore, at least one through hole for collecting sound that communicates each small space with the outside is provided in each of two opposing inner walls of the casing forming the storage space, and the user side wall is penetrated. With respect to the hole, the opening ratio with respect to the wall surface of the housing forming the storage space is approximately 5%, and the total area is equal to or greater than the total area of the sound collecting holes facing the directional microphone, With respect to the through hole, the opening ratio with respect to the wall surface of the housing forming the storage space is approximately 10%, and the total area is equal to or greater than the total area of the sound collecting holes facing the directional microphone. it can.

  As a result of intensive studies, the present inventor has made the opening ratio of the sound collecting hole of the housing wall on the user side about 5% with respect to the wall surface of the housing, and the area is the total area of the sound collecting holes of the directional microphone. From the viewpoint of protection of the directional microphone, the through hole of the other wall has an aperture ratio of about 10% with respect to the wall surface of the housing and the area is equal to or larger than the total area of the sound collecting holes of the directional microphone. In addition, we found out that it is optimal from the viewpoint of maintaining the directivity of the directional microphone.

  Furthermore, an elastic member can be inserted into at least one of the two small spaces. If it does in this way, since one of two small spaces becomes small by the elastic member, generation | occurrence | production of the sound wave in a small space by the mechanical vibration of a bone conduction speaker will further be suppressed.

  Furthermore, the elastic member and the directional microphone can be arranged so as to be sandwiched between two opposing inner walls of the casing. In this way, since the directional microphone is integrated with the elastic member and is held between the housings with high rigidity, the relative distance between the sound collection surface of the directional microphone and the inner wall of the housing is relatively small. The fluctuation is reduced, and the generation of sound waves due to the mechanical vibration of the bone conduction speaker in a small space is suppressed.

  Furthermore, the elastic member can be brought into contact with a gap between the structure and the inner wall of the housing. In this way, since the airtightness of the storage space of the directional microphone can be increased, it is possible to prevent sound waves generated in other spaces in the enclosure from flowing around the sound collection surface of the directional microphone. be able to.

  Furthermore, the structure body is two cylindrical ribs provided on each of two opposing inner wall walls of the housing, and the storage space is formed by fitting the two cylindrical ribs into a fitted cylinder. The gap between the ribs can be filled with an adhesive. In this way, since the airtightness of the storage space of the directional microphone can be further increased, the sound waves generated in other spaces in the enclosure wrap around the sound collection surface of the directional microphone. It can be prevented from coming. In addition, since the rigidity of the entire support structure of the directional microphone can be increased, the variation in the distance between the sound collection surface of the directional microphone and the inner wall of the housing is reduced, and therefore, in the storage space of the directional microphone. The generation of sound waves due to mechanical vibration is suppressed.

  In the bone conduction transmitter / receiver according to the present invention, since the storage space of the directional microphone is sealed, the sound wave generated by the mechanical vibration of the bone conduction speaker from the other space in the housing to the storage space of the directional microphone. Is prevented from wrapping around from other spaces. In addition, since the directional microphone is held with high rigidity by a structure or the like and its storage space is configured to be as small as possible, sound waves generated by mechanical vibration of the bone conduction speaker in the storage space of the directional microphone can be obtained. Occurrence is suppressed. Furthermore, since the sound wave capturing hole is provided in the housing so as not to lower the directivity of the directional microphone, the use of the directional microphone also improves the transmission performance in a noisy environment. As described above, by using the bone conduction transmitting / receiving apparatus of the present invention, echo back can be reduced and a comfortable transmitting / receiving environment can be realized even in a noisy environment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a bone conduction transmitter / receiver according to the present invention will be described in detail with reference to the drawings. This bone conduction transmitter / receiver device includes a bone conduction speaker that converts sound information such as voice and music into mechanical vibration, and a directional microphone that is highly sensitive to a specific direction. In this apparatus, a bone conduction speaker is used to receive a call, and a directional microphone is used to transmit. The bone conduction speaker converts an electrical signal including sound information sent from a host device into mechanical vibration. The directional microphone collects ambient sounds such as a user's voice, converts the voice into an electric signal, and sends it to a host device. The directional microphone collects ambient sounds from both sides, and obtains directivity from the difference between the sound collection results on each side. In the bone conduction transmitter / receiver according to the embodiment of the present invention, the directional microphone picks up the sound wave generated in the housing by the mechanical vibration of the bone conduction speaker, thereby preventing the echo back.

  FIG. 1 is a perspective view for explaining the overall configuration of the bone conduction transducer 1 according to the present embodiment. The bone conduction transmitter / receiver device 1 according to the present embodiment conforms to a predetermined wireless communication standard, and operates as a slave unit of the mobile phone while performing wireless communication with a mobile phone (not shown). In the present embodiment, it is assumed that the bone conduction transducer 1 conforms to, for example, the Bluetooth (registered trademark) standard.

  As shown in FIG. 1, a bone conduction transmitter / receiver device 1 includes a bone conduction speaker 2, a call button 3, a volume switch 4, a light emitting diode (hereinafter abbreviated as “LED”) 5, a main body. A case 8 and a flip 9 are provided.

  The bone conduction speaker 2 converts a radio signal transmitted from a mobile phone into mechanical vibration. The call button 3 is a button for accepting an operation input such as a call start or a call end of the bone conduction transmitting / receiving apparatus 1. The volume switch 4 is an operation switch for adjusting the volume of the bone conduction speaker 2. The LED 5 is provided to notify the user of the state of the device. The LED 5 blinks when there is an incoming call, for example, and notifies the user to that effect.

  The main body case 8 is a housing of the bone conduction transmitter / receiver 1. A bone conduction speaker 3, a call button 4, a volume changeover switch 4, and an LED 5 are embedded in the main body case 8. Although not shown, the main body case 8 also houses a circuit board for controlling wireless communication and the like, and switches for switching the microphone to be used between the directional microphone 6 and the omnidirectional microphone 7. Holding.

The flip 9 is a separate casing from the main body case 8 that is connected to the main body case 8 via a hinge portion 10 that is a part of the main body case 8. The hinge portion 10 pivotally supports the flip 9 on the main body case 8 so as to be rotatable. When the bone conduction transducer 1 is not used, the flip 9 is
Although stored in the recess of the main body case 8 in which the call button 3 and the LED 5 are disposed, when in use, it is rotated around the hinge portion 10 and moved to a position as shown in FIG. As will be described later, a directional microphone 6 and an omnidirectional microphone 7 are accommodated in the flip 9.

  The bone conduction transmitter / receiver device 1 according to the present embodiment is generally used in a state where the bone transmission speaker 2 is in contact with the vicinity of the user's ear and the flip 9 is positioned in the vicinity of the user's mouth. Is.

  Next, the internal structure of the flip 9 will be described. 2 to 7 show the internal structure of the flip 9. FIG. 2 shows an exploded perspective view of the inside of the flip 9. FIG. 3 shows a sectional view of the inside of the flip 9. 4 is a perspective view for explaining the inside of the flip top 11 constituting the flip 9, and FIG. 5 is a plan view for explaining the inside of the flip top 11. FIG. 6 is a perspective view for explaining the inside of the lower flip 12 constituting the flip 9. FIG. 7 is an enlarged cross-sectional view of the vicinity of the holding portion of the directional microphone 6 in the cross-sectional view of FIG.

  As shown in FIG. 2, the flip 9 includes a flip upper 11 and a flip lower 12 as a casing, and the flip 9 is formed by these two. At the time of use, the flip top 11 faces the user side, and the flip bottom 12 faces the opposite. In the flip 9 formed by the flip upper 11 and the flip lower 12, as shown in FIGS. 2 and 3, a directional microphone 6, an omnidirectional microphone 7, two dustproof sheets 13, The contact rubber 14, the antenna mounting substrate 15, and the flip stopper 16 are accommodated.

  The directional microphone 6 and the omnidirectional microphone 7 pick up the user's voice. Both are switched and used. As shown in FIG. 2, the directional microphone 6 has a disk shape, sound collecting holes are formed on both circular surfaces, and both surfaces are sound collecting surfaces. Although not shown, the directional microphone 6 has thirteen sound collecting holes with a diameter of about 0.4 mm on the surface on the upper side of the flip 11, and has a diameter of about 0.4 mm on the surface on the lower side of the flip 12. Two 0.6 mm sound collecting holes are provided. The omnidirectional microphone 7 is also disk-shaped, and its sound collection surface is provided only on the circular surface on the flip 11 side.

  The dustproof sheet 13 is for protecting the directional microphone 6 from foreign matters such as dust mixed from the outside. The contact rubber 14 is an elastic member for holding the directional microphone 6. The antenna mounting board 15 is a board on which an antenna for wireless communication, for example, Bluetooth communication is mounted. The flip stopper 16 is a buffering agent for relaxing the collision sound with the main body case 8 when the flip 9 is closed.

  Furthermore, as shown in FIGS. 4 and 5, cylindrical ribs 11 c and cylindrical ribs 11 d as structures for holding the directional microphone 6 and the omnidirectional microphone 7 are formed on the inner wall of the upper flip 11. As shown in FIG. 6, a cylindrical rib 12 b for holding the directional microphone 6 is provided on the inner wall of the lower flip 12. As shown in FIG. 7, the directional microphone 6 is accommodated in a cylindrical space formed by the cylindrical rib 11 c, the cylindrical rib 12 b, the inner wall of the upper flip 11, and the inner wall of the lower flip 12. Further, the omnidirectional microphone 7 is accommodated in a cylindrical space formed by the cylindrical rib 11 b on the flip 11.

  That is, the cylindrical space formed by the cylindrical rib 11 c, the cylindrical rib 12 b, the upper flip 11 and the lower flip 12 is a storage space for the directional microphone 6. FIG. 7 shows the storage space 21 (a space including small spaces 26 and 27 described later). In FIG. 7, a flip internal space 22 which is a space in the flip 9 other than the storage space 21 is also shown. As shown in FIG. 7, the storage space 21 is formed by fitting the cylindrical rib 11c and the cylindrical rib 12b, and the storage space 21 and the flip inner space 22 are partitioned. Since there is no ventilation between the storage space 21 and the in-flip space 22, the propagation of sound waves between each other is prevented. Therefore, since the mechanical vibration of the bone conduction speaker 2 is transmitted to the flip 9, sound waves generated in the flip inner space 22 are prevented from being transmitted to the storage space 21 and picked up by the directional microphone 6.

  The cylindrical rib 11 c is formed integrally with the upper flip 11, and the cylindrical rib 12 b is formed integrally with the lower flip 12. Accordingly, the cylindrical ribs 11 c and 12 b have rigidity equal to or higher than that of the upper flip 11 and the lower flip 12. As shown in FIG. 7, the directional microphone 6 is fitted to the cylindrical rib 11 c and is held by the cylindrical rib 11 c having rigidity equal to or higher than that of the flip 9. Thus, if the directional microphone 6 is held by a highly rigid holding member, even if mechanical vibrations of the bone conduction speaker 2 are transmitted to the inner walls of the upper flip 11 and the lower flip 12, the collection of the directional microphones 6 is achieved. The relative variation in the distance between the sound surface and the inner wall of the upper flip 11 and the lower flip 12 is reduced.

  In addition, as shown in FIG. 7, when the directional microphone 6 is stored in the storage space 21, the two small spaces 26 and 27 facing each sound collecting surface of the directional microphone 6 are stored in the storage space 21. Will be formed. The smaller the two small spaces 26 and 27 are, the smaller the relative fluctuation in the distance between the sound collecting surface of the directional microphone 6 and the inner wall of the upper flip 11 and the lower inner wall of the flip 12. Generation of sound waves in the storage space of the directional microphone 6 due to the mechanical vibration 2 is suppressed. However, if the sound collection hole of the directional microphone 6 is blocked in the small spaces 26 and 27, the directivity of the directional microphone 6 is lowered. Therefore, the small spaces 26 and 27 are connected to the directional microphone 6. It is necessary to have a size that does not block the sound collection hole.

  Due to the support structure of the directional microphone 6 as described above, the sound wave generated in the flip inner space 22 due to the mechanical vibration of the bone conduction speaker 2 does not reach the sound collection surface of the directional microphone 6 and is stored. Since the generation of sound waves in the space 21 (small spaces 26 and 27) is also suppressed, the occurrence of echo back can be prevented.

  Also, as shown in FIGS. 4 and 5, a sound wave capturing hole 11a, which is a through hole, is provided in a substantially central portion of the inner wall of the flip upper 11 that forms the storage space 21 together with the cylindrical rib 11c. . In addition, a sound wave capturing hole 11b, which is a through hole, is provided on the inner wall of the upper flip 11 at a substantially central portion of the portion where the cylindrical rib 11d is formed. The sound wave capturing hole 11 a is a capturing hole for the directional microphone 6, and the sound wave capturing hole 11 b is a capturing hole for the omnidirectional microphone 7. Further, as shown in FIG. 6, four sound wave capturing holes 12a, which are through holes, are provided in the substantially central portion of the inner wall of the lower flip 12 that forms the storage space 21 together with the cylindrical rib 12a. The four sound wave capturing holes 12 a are capturing holes for the directional microphone 6.

  In order to obtain directivity, in the directional microphone 6, it is necessary to take in sound waves from both sound collecting surfaces. Therefore, a sound wave capturing hole 11 a is provided in the upper flip 11, and a sound wave capturing hole 12 a is provided in the lower flip 12. Is provided. The sound wave capturing holes 11a and 12a have a diameter of 1.4 mm and an area of about 1.5 square mm. The sound wave capturing hole 12a has a diameter of 1 mm, and the total area of the four is as follows. , Approximately 3 square mm. The area of the sound wave capturing hole 11 a is larger than the total area of the sound collecting holes on the flip upper 11 side of the directional microphone 6, and the total area of the sound wave capturing hole 12 a is below the flip 12 side of the directional microphone 6. It is larger than the total area of the sound collecting holes.

  The sound collection surface of the directional microphone 6 has a diameter of about 5.8 mm and an area of about 26 square mm. Therefore, the aperture ratio of the sound wave capturing hole 11a with respect to the inner wall portion of the upper flip 11 constituting the storage space is approximately 5%, and the sound wave capturing hole for the inner wall portion of the lower flip 12 constituting the storage space. The aperture ratio of 12a is approximately 10%.

  In order to maintain the directivity of the directional microphone 6 appropriately, it is necessary to consider the balance of sound waves taken into the sound collecting holes arranged on both sound collecting surfaces of the directional microphone 6. In order to efficiently receive sound waves, it is ideal that there are no obstructive members (that is, flip top 11 or flip bottom 12) around the directional microphone 6, but the appearance design, Considering the manufacturing cost or the necessity of protecting the directional microphone 6 from externally applied pressure, impact, etc., the outer wall and its supporting structure must be provided around the directional microphone 6. In order to improve directivity, it is desirable to increase the aperture ratio of the sound wave capturing holes 11a and 12a. However, in order to protect the directional microphone 6, the sound wave capturing holes 11a and 12a are made small. There is a need. As a result of considering these contradictory conditions, the sizes of the small spaces 26 and 27 of the directional microphone 6 as described above, the areas of the sound wave capturing holes 11a and 12a, and the aperture ratio are employed.

  That is, the distance from the inner wall of the upper flip 11 and the lower flip 12 to the sound collecting surface of the directional microphone 6 and the directivity can be selected from conditions that can be practically set as design conditions for the area and aperture ratio of the sound wave capturing hole. As an optimal condition that can effectively protect the directional microphone 6 without significantly degrading the directivity of the directional microphone 6, the small spaces 26 and 27 are provided with sound collecting holes on both sound collecting surfaces of the directional microphone 6. It is small enough not to be blocked, and the total area of the sound wave acquisition holes 11a and 12a is not less than the total area of the sound collection holes of the directional microphone 6 on the same side, and the sound wave acquisition holes 11a and 12a are opened. The condition was selected such that the rate was approximately 5% on the flip top 11 side and approximately 10% on the flip bottom 12 side.

  In addition, as shown in FIG. 7, the contact rubber 14 is inserted into the small space 27. In this way, since the small space 27 can be further reduced, generation of sound waves in the small space 27 of the directional microphone 6 due to mechanical vibration of the bone conduction speaker 2 is suppressed. Become.

  Further, as shown in FIG. 7, in the cylindrical ribs 11 c and 12 b, a contact rubber 14, a directional microphone 6, and a dustproof sheet are provided between the inner wall of the upper flip 11 and the inner wall of the lower flip 12. 13 is arranged so as to be sandwiched. In this way, the contact rubber 14 is crushed, and the directional microphone 6 is pressed against the flip top 11 by the reaction force. As a result, the directional microphone 6 is integrated with the flip top 11 and is held with high rigidity, so that the variation in the distance between the sound collection surface of the directional microphone 6 and the inner wall of the flip top 11 is changed. Therefore, the generation of sound waves in the small space 26 due to mechanical vibration of the bone conduction speaker 2 is suppressed.

  Further, FIG. 7 shows a gap 17 between the fitted cylindrical rib 11c and the cylindrical rib 12b and around the lead wire outlet. The contact rubber 14 is in contact with a gap 17 between the cylindrical rib 11 c and the inner wall of the lower flip 12. In this way, since the airtightness of the small space 27 can be further improved, it is possible to prevent sound waves generated in the flip inner space 22 from entering around the sound collection surface of the directional microphone 6. .

  As shown in FIGS. 4 and 5, the cylindrical rib 11c is provided with a lead wire takeout notch 11e, and as shown in FIG. 6, the cylindrical rib 12b is provided with a lead wire takeout. A notch 12c is provided. The lead wire 25 (see FIG. 2) of the directional microphone 6 has lead wire take-out notches 11e and 12c provided on the flip upper 11 and the lower flip 12, and a notch groove (not shown) provided on the contact rubber 14. ) Etc. are taken out from the lead wire outlet.

  An adhesive is inserted into the gap 17. In this way, since the airtightness of the storage space 21 of the directional microphone 6 can be further increased, sound waves generated in the flip inner space 22 wrap around the sound collection surface of the directional microphone 6. Can be prevented. Moreover, since the rigidity of the entire support structure of the directional microphone 6 can be increased by inserting an adhesive into the gap 17, the directional microphone 6 and the inner walls of the flip upper 11 and the flip lower 12 are arranged. Since the relative fluctuation of the interval becomes small, the generation of sound waves due to mechanical vibration in the storage space of the directional microphone 6 is suppressed.

  As described above in detail, if the directional microphone 6 is used as a microphone for transmission, the user's voice is strongly picked up and it is difficult to pick up surrounding noise, so that the transmission performance in a noisy environment is improved. Will be able to. Further, since the directional microphone 6 is held by a cylindrical rib 11c having rigidity equal to or higher than that of the flip 9, the distance between the sound collection surface of the directional microphone 6 and the inner wall of the flip upper 11 and the flip lower 12 is set. The fluctuation is reduced, and the generation of sound waves due to these mechanical vibrations is suppressed. Furthermore, since the storage space 21 of the directional microphone 6 is partitioned from the flip inner space 22 by the cylindrical rib 11c or the like, the sound wave generated in the flip inner space 22 enters the storage space 21 of the directional microphone 6. It will not be transmitted. Therefore, if the bone conduction transmitting / receiving apparatus 1 according to the present embodiment is used, echo back due to mechanical vibration of the bone conduction speaker 2 is reduced, and comfortable transmission / reception can be performed even in a noisy environment.

  If the bone conduction transmitter / receiver device 1 according to the present embodiment is used, it is effective not only for people who have a disability in the sound transmission part of the outer ear and the inner ear, but also for use in a noise environment such as a construction site or a station platform. It is.

  In the present embodiment, the area of the sound wave capturing hole 11a is larger than the total area of the sound collecting holes on the same side of the directional microphone 6, but the area of the sound wave capturing hole 11a is smaller than that of the directional microphone 6. It does not have to be less than the total area of the sound collecting holes on the same side. The total area of the sound wave capturing holes 12a is larger than the total area of the sound collecting holes on the same side of the directional microphone 6, but the total area of the sound wave capturing holes 12a is on the same side of the directional microphone 6. It does not have to be less than the total area of the sound collection holes.

  In this embodiment, only the directional microphone 6 is stored in the sealed storage space 21. However, the omnidirectional microphone 7 may be stored in the same sealed space. is there.

  In this embodiment, the bone conduction transmitter / receiver device 1 is a mobile phone slave unit. However, the present invention is not limited to this, and the bone transmission transmitter / receiver device 1 may be a fixed phone slave unit. The device itself may be a mobile phone or a transceiver. Further, the bone transmission / reception device may be connected to the host device by wire or may be a landline telephone handset.

  Further, in this embodiment, since the disc-shaped directional microphone 6 is employed, the rib as a structure that holds the disk is cylindrical, but the shape of the rib (structure) is that of the directional microphone 6. Of course, it can be appropriately changed depending on the shape. For example, if the directional microphone is a rectangular plate, the shape of the rib may be a rectangular frame.

1 is a perspective view of a bone conduction transducer according to an embodiment of the present invention. It is a disassembled perspective view of the flip of FIG. It is sectional drawing of the flip of FIG. It is a perspective view which shows the inner side on the flip of FIG. It is a top view which shows the inner side on the flip of FIG. It is a perspective view which shows the inner side under the flip of FIG. It is an expanded sectional view of the flip near the holding part of a directional microphone.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bone conduction transmitter / receiver 2 Bone conduction speaker 3 Call button 4 Volume switch 5 LED
6 Directional microphone 7 Non-directional microphone 8 Main body case 9 Flip 10 Hinge part 11 Flip upper 12 Flip lower 11a, 11b, 12a Sound wave capturing holes 11c, 11d, 12b Cylindrical ribs 11e, 12c Lead wire takeout notch 13 Dust-proof sheet 14 Adhesive rubber 15 Antenna mounting board 16 Flip stopper 17 Gap 21 Storage space 22 Flip inner space 25 Lead wires 26 and 27 Small space

Claims (7)

A bone conduction speaker for receiving sound that converts sound information into mechanical vibration;
A directional microphone having a sound collecting surface having sound collecting holes on both sides;
A bone conduction transducer comprising at least a housing for housing the directional microphone,
A structure for holding the directional microphone is provided on the inner wall of the housing,
The structure is
A bone conduction transmitter / receiver device that is formed so as to partition a storage space in which the directional microphone is stored and another space in the housing, and has rigidity equal to or higher than that of the housing. The storage space is
Formed by two opposing inner walls of the housing and the structure;
In the state where the directional microphone is stored in the storage space, two small spaces facing each sound collection surface of the directional microphone are formed in the storage space,
The two small spaces are
The bone conduction transmitter / receiver according to claim 1, wherein the sound collecting hole of the directional microphone is small enough not to be blocked. At least one through-hole for collecting sound that communicates the small space with the outside is provided in each of two opposing inner walls of the housing forming the storage space,
With respect to the through-holes on the user-side wall, the opening ratio to the wall surface of the housing forming the storage space is approximately 5%, and the total area is greater than or equal to the total area of the sound collecting holes facing the directional microphone. Yes,
The through hole of the other wall has an aperture ratio of about 10% with respect to the wall surface of the housing forming the storage space, and the total area is equal to or greater than the total area of the sound collecting holes facing the directional microphone. The bone conduction transmitter / receiver according to claim 2.   The bone conduction transducer according to any one of claims 1 to 3, wherein an elastic member is inserted into at least one of the two small spaces. The elastic member is
Along with the directional microphone
The bone conduction transmitter / receiver according to claim 4, wherein the bone conductive transmitter / receiver is sandwiched between two opposing inner walls of the casing. The elastic member is
The bone conduction transducer according to claim 4 or 5, wherein the bone conduction transducer is in contact with a gap between the structure and an inner wall of the housing. The structure is
Two cylindrical ribs provided on each of two opposing inner wall walls of the housing,
The storage space is formed by fitting the two cylindrical ribs,
The bone conduction transducer according to any one of claims 1 to 6, wherein the gap between the fitted cylindrical ribs is filled with an adhesive.

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