JP2007103989A - Receiver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a receiver of a bone conduction or cartilage conduction type with excellent sound quality, a high transduction efficiency, and good mountability. <P>SOLUTION: The receiver includes: a rod-shaped bone conduction speaker unit 11; a ring-shaped vibration transmission unit 12 containable in a cavity including a cavum conchae and shaped and sized to be in press-contact between a tragus 14 and an antitragus 18; and a support 13 for supporting the bone conduction speaker unit and connected to an auricula contact part. Further, the bone conduction speaker unit is a composite of a piezoelectric bimorph and a flexible substance, and supported at its end in the length direction by the support. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a receiver using a bone conduction speaker.

  There are two types of receivers that transmit sound information to the inner ear, which is a human auditory organ, depending on the vibrator that forms the sound generation unit (speaker). The air-conducting type handset is designed to transmit sound information to the inner ear via the air conduction through the middle ear transmission system including the ear canal and the eardrum by placing a speaker at the entrance of the ear canal.

  A bone-conducted handset directly transmits voice information to the inner ear through the bone tissue without passing through the middle ear transmission system by pressing a transducer on the skin on the bone tissue near the auricle and mandible. Designed to communicate. The purpose of using such a bone conduction receiver is mainly for hearing aid for the hearing impaired when the function of the middle ear is deteriorated. Has begun to be utilized as.

  Air conduction type handsets are widely used in general, but as a well-known technology related to bone conduction type handsets, for example, a bone conduction speaker is placed in a place other than the entrance of the ear canal and the ear canal is left open. Proposals have been made of a structure in which sound information can be heard by bone conduction sound, a structure in which the vibration surface of the bone conduction speaker is in contact with the auricle, and the like. Such a receiver is disclosed in Patent Document 1 or Patent Document 2.

JP 2003-18683 A JP 2001-320790 A

  However, the conventional bone conduction handset has a large shape and a weight as heavy as 10 g or more, and also in terms of sound quality such as frequency characteristics, conversion efficiency from electric signal to sound vibration or wearability on the head. There was nothing that met all, and there was a problem in practical use.

  In order to solve such problems, it is an object of the present invention to provide a low-cost bone-conduction or cartilage-conduction receiving device that is excellent in sound quality, has high conversion efficiency, and is easy to wear.

  The present invention employs the following means in order to solve the above problems. In other words, through various experiments, it has been confirmed that the vicinity of the tragus can transmit sound most sensitively as a vibration input unit for bone conduction, and the user feels a burden and pressure when the vibration transmission unit is brought into contact with the tragus portion. The main points are that there are few, that it can be heard without closing the air guide, and that it can be supplied at a low price.

  According to the present invention, there is provided a receiving device including a bone conduction speaker unit that generates acoustic vibrations and a vibration transmission unit that transmits acoustic vibrations generated by the bone conduction speaker units, the bone conduction speaker unit and the vibrations. A receiving device is obtained that is mechanically coupled to the transmission unit and has a shape that fits in a depression in the concha cavity and can come into contact with the tragus and the cusp.

  The receiving device according to the present invention is configured so that a vibration transmitting portion protruding from and coupled to a bone conduction speaker can be brought into contact with the face near the tragus, and transmits audio information to the inner ear via the cartilage of the tragus. Therefore, an excellent sound quality can be obtained because the sound transmission path via the cartilage guide can be used.

  Further, according to the present invention, there is obtained a receiving device characterized in that the vibration transmitting portion has an annular shape having one or more through holes or a shape in which a part of the annular shape is missing.

  The earpiece according to the present invention fits in a recess including the concha cavity, has a ring shape or a shape in which a part of the ring is missing, and has an auricle contact portion that does not block the external auditory canal, so it is easy to wear, In addition, as a sound generation unit for generating sound information and transmitting it to the inner ear, sound generated by air conduction for transmitting sound information to the inner ear via the external auditory canal and the middle ear as well as the sound transmission path via the cartilage conduction. It can be set as the structure which has the dual path | route transmission function using both transmission paths.

  Therefore, it is possible to listen to the sound with natural sound quality with better clarity, and it is possible to make full use of the basic function of the bone conduction type that has never existed before. This can be used for the user in the same way as a conventional air-conduction earphone, and at the same time, the external auditory canal is completely open and the surrounding voice is not blocked, so there is no such thing in the existing receiver. A receiver with a new function can be realized.

  According to the present invention, it is possible to obtain a receiving device characterized in that the bone conduction speaker portion has a rod shape, and the vibration transmitting portion is mechanically coupled to an end portion in the longitudinal direction.

  The receiver according to the present invention can be driven efficiently by supporting the bone conduction speaker portion at the end in the longitudinal direction.

  Further, according to the present invention, there can be obtained a receiving device characterized in that the bone conduction speaker part is composed of a piezoelectric element and a covering part, and the covering part is made of a flexible substance.

  In the present invention, the piezoelectric vibrator is used as the converter from the electric signal to the sound vibration, so that the conversion efficiency, that is, the efficiency is high, and the adoption of the piezoelectric element makes it possible to realize a very light and simple configuration.

  In addition, the bone conduction speaker unit can be made close to the acoustic impedance of the human body by being composed of a piezoelectric vibrating body that combines a piezoelectric element and a flexible material, thereby reducing the resonance sharpness Q of the vibrating body and reducing the frequency. The characteristics can be flattened.

  In addition, according to the present invention, there is obtained a receiving device characterized in that the covering portion of the bone conduction speaker portion and the vibration transmitting portion are integrally formed of a flexible material.

  Furthermore, the bone conduction speaker covering member, the auricle contact part and the support part can all be made of the same flexible material, and can be integrally formed with a single mold, leading to a reduction in the number of parts and manufacturing man-hours. As a result, a low-cost bone conduction receiver can be realized.

  As described above, according to the present invention, it is possible to provide an inexpensive bone-conduction or cartilage-conduction receiving device that is excellent in sound quality, has high conversion efficiency, and is easy to wear.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view of a receiver according to the first embodiment. In the receiving apparatus according to the first embodiment, the vibration transmitting unit 12 is coupled to and protrudes from one end in the longitudinal direction of the rod-shaped bone conduction speaker unit 11 by the support unit 13. The vibration transmitting portion 12 has an outer shape that fits in the concha cavity portion, has a diameter of 15 mm, a protruding dimension of 5 mm, and an annular shape having a through hole 16 having a diameter of 5 mm at the center. Since this vibration transmission part 12 should just be stored in the concha cavity part, and should just contact | abut to the tragus and the rosicle, it is not limited to the said dimension, A diameter is 5-20 mm and a protrusion dimension is also in the range of about 3-10 mm. It is desirable to set according to the user. Furthermore, the shape of the through-hole 16 or the vibration transmitting portion 12 is not limited to the shape as shown in FIG. 1, but may be a shape with a roundness that is more wearable and does not give a feeling of pressure. The bone conduction speaker unit 11 is fixed inside a rectangular notch 17 formed in the support unit 13.

  FIG. 2 is a diagram illustrating a state in which the receiver according to the first embodiment is worn on the left ear. In the receiver according to the first embodiment, as shown in FIG. 2, the vibration transmitting unit 12 is placed in the depression of the concha cavity, and is pressed against the tragus 14 and the rosicle 18. The bone conduction speaker unit 11 directly transmits the sound vibration generated in contact with the tragus or the vicinity thereof to the tragus or the vicinity thereof, and the sound vibration generated by the bone conduction speaker unit 11 further passes through the vibration transmission unit 12. Thus, the structure is transmitted to the cartilage and facial bone tissue in the vicinity of the tragus 14. At this time, since the vibration transmitting portion 12 has the through hole 16 in the central portion, the air conduction sound can be heard without covering the ear canal and there is no feeling of blockage.

  FIG. 3 is a cross-sectional view of the bone conduction speaker unit according to the first embodiment. The bone conduction speaker unit 11 used in the first embodiment is composed of two piezoelectric ceramic plates 22 arranged so as to sandwich a metal shim 21 made of a metal elastic plate from above and below. In FIG. A rectangular plate-shaped piezoelectric bimorph element 24 in the direction is covered with a covering layer 23 made of a flexible material. The piezoelectric bimorph element 24 vibrates by applying a voltage so that one piezoelectric ceramic plate 22 extends in the longitudinal direction and the other contracts in the longitudinal direction.

  The piezoelectric bimorph element 24 used in the first embodiment is composed of a piezoelectric ceramic plate 22 that mainly generates a displacement in the longitudinal direction by utilizing the lateral effect of piezoelectricity. The piezoelectric ceramic plate 22 is rectangular and has a thickness direction. Polarization was performed to cause expansion and contraction in accordance with electric signals applied to the upper and lower surfaces. In addition, a configuration in which the electrodes are stacked in the thickness direction, the electrodes are divided into two groups for each layer, and a configuration in which polarization and voltage application can be applied to each layer is adopted, and the driving voltage is greatly reduced. Electrical connections are not shown.

  Here, a manufacturing method of the piezoelectric bimorph element 24 will be described. For the two piezoelectric ceramic plates 22, piezoelectric ceramics (trade name Nepec 10) manufactured by NEC TOKIN Corporation are used, and the dimensions are 30 mm in length, 3 mm in width, and 0.2 mm in thickness. The shim is made of brass having a thickness of 50 μm, and its length and width are substantially the same as those of the piezoelectric ceramic plate. These are bonded together with an epoxy-based adhesive, and an electrode is provided on the outer main surface of the piezoelectric ceramic plate, and a lead wire is drawn out from this electrode and shim. Here, the piezoelectric ceramic has a structure in which the electrodes are laminated in the thickness direction. If the structure is such that the electrodes are divided into two groups for each layer and polarization and voltage can be applied to each layer, there is an advantage that the driving voltage can be greatly reduced. In Example 1, a piezoelectric ceramic plate having an integrally fired structure in which 50 μm layers were laminated in four layers was used, and the two piezoelectric ceramic plates were electrically connected in parallel.

  Next, in order to form the bone conduction speaker unit 11 using the piezoelectric bimorph element 24, liquid urethane rubber is poured over the entire surface of the piezoelectric bimorph element 24 using a brass mold, and the thickness direction is determined by a curing process. A coating layer was formed on the two surfaces with a thickness of 2 mm. The resonance frequency and the Q of the vibrating body can be adjusted by the thickness of the coating layer.

  As shown in FIG. 1, the bone conduction speaker unit 11 obtained in this way is bonded and fixed at the end in the longitudinal direction using an epoxy adhesive inside the notch 17 of the acrylic support 13. Furthermore, the support part 13 and the acrylic vibration transmission part 12 were joined and fixed to obtain a receiver in the form of the first embodiment.

  When a voice signal of about 7 Vrms is input to the receiver of the first embodiment through the connection cord 15 and the vibration generated by the bone conduction speaker unit 11 is received in the vicinity of the tragus 14, music and music with a clear and sufficient volume feeling can be obtained. It was confirmed that it was possible to listen to audio information. In addition, it was confirmed that the bone conduction receiver obtained in Example 1 weighs only 3 g, and the burden on the user is light.

  In the first embodiment, a rectangular plate-shaped piezoelectric bimorph is used for the bone conduction speaker. However, a piezoelectric unimorph can also be used, and the shape is not limited to the rectangular plate shape, and a general piezoelectric material having a circular, elliptical, or polygonal shape. It may be a vibrating body. Furthermore, a larger volume can be obtained by stacking a plurality of piezoelectric bimorphs and connecting them so as to be driven in the same direction.

  FIG. 4 is a perspective view of a receiver according to the second embodiment. The receiver according to the second embodiment is configured such that the vibration transmitting unit 12 is directly joined to one end in the longitudinal direction of the rod-shaped bone conduction speaker unit 11. For the bone conduction speaker unit 11, the same piezoelectric bimorph element as in Example 1 was used. Moreover, the shape of the vibration transmission part 12 was made into the shape which has the notch part 19 in a part of ring shape.

  Further, in the second embodiment, a piezoelectric bimorph element is arranged in a mold provided with a portion where the vibration transmitting portion 12 shaped to fit in the concha cavity portion is formed, and liquid urethane rubber is poured into the mold and cured. The bone conduction speaker unit 11 and the vibration transmitting unit 12 were integrally formed to form a receiver. In this way, by forming the bone conduction speaker unit 11 and the vibration transmitting unit 12 integrally, it is possible to provide a low-cost receiver that is rich in mass productivity.

  Also in the second embodiment, when an audio signal of about 7 Vrms is input through the connection cord 15 and the vibration generated by the bone conduction speaker unit 11 is received in the vicinity of the tragus 14, a clear and sufficient volume feeling is obtained as in the first embodiment. It was confirmed that it was possible to listen to music and voice information, and it was also confirmed that it was lightweight and the burden on the user was light.

  As described above, according to the present invention, it is possible to provide an inexpensive bone-conduction or cartilage-conduction receiving device that is excellent in sound quality, has high conversion efficiency, and is easy to wear.

  The present invention can be used not only as an acoustic receiver, but also as a sound receiving device for a mobile phone mobile terminal device, a mobile terminal device, etc. as well as various acoustic devices.

1 is a perspective view of a receiver according to Embodiment 1. FIG. The figure which shows the state which mounted | wore the left ear with the telephone receiver by Example 1. FIG. Sectional drawing of the bone conduction speaker part by Example 1. FIG. FIG. 6 is a perspective view of a receiver according to a second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Bone conduction speaker part 12 Vibration transmission part 13 Support part 14 Tragus 15 Connection cord 16 Through-hole 17 Notch part 18 Notch part 19 Notch part 21 Metal shim 22 Piezoelectric ceramic board 23 Covering layer 24 Piezoelectric bimorph element

Claims (5)

  A receiving device comprising a bone conduction speaker unit that generates acoustic vibration and a vibration transmission unit that transmits acoustic vibration generated by the bone conduction speaker unit, wherein the bone conduction speaker unit and the vibration transmission unit are mechanical And a shape that fits into a concavity cavity and abuts against the tragus and the tragus.   The receiving device according to claim 1, wherein the vibration transmitting unit has an annular shape having one or more through holes or a shape in which a part of the annular shape is missing.   The receiving apparatus according to claim 1, wherein the bone conduction speaker unit has a bar shape, and the vibration transmission unit is mechanically coupled to an end portion in a longitudinal direction thereof. .   The receiving device according to any one of claims 1 to 3, wherein the bone conduction speaker unit includes a piezoelectric element and a cover, and the cover includes a flexible material.   The receiving device according to any one of claims 1 to 4, wherein the covering portion of the bone conduction speaker portion and the vibration transmitting portion are integrally formed of a flexible material.

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