JP2006217518A - Electroacoustic transducer device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact and lightweight electroacoustic transducer device which has a speaker function and a receiver function, and can reinforce bass. <P>SOLUTION: The electroacoustic transducer device comprises an electroacoustic transducer 10 for converting an electrical signal into a sound; and a cabinet 20 which houses the electroacoustic transducer 10, and also forms a first volume space 31 acoustically coupled to the sound generation side of the electroacoustic transducer 10, and a second volume space 32 acoustically coupled to the opposite side of the sound generation side. The cabinet 20 has a first sound emitting holes 22a by which the electroacoustic transducer 10 is operated as a speaker by communicating the first volume space 31 with a speaker function side external space A, and a second sound emitting holes 24a by which the electroacoustic transducer 10 is operated as a receiver by communicating the first volume space 31 with a receiver function side external space B of an opposite side of the speaker function side external space A. Also, a port 30 is provided with a specified length which communicates the second volume space 32 with an external space. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electroacoustic transducer comprising an electroacoustic transducer and a housing that houses the electroacoustic transducer, and in particular, an electrical device that serves as both a receiver and a speaker by an acoustic path structure formed in the housing. The present invention relates to an acoustic transducer.

  For example, a cellular phone requires a speaker that generates a ringtone and a receiver that reproduces an audio signal, the speaker is directed to the outside of the phone body, and the receiver is located on the inside of the phone body (a surface having a display surface and an operation unit). Each is provided independently.

  Since the mobile phone having such a structure is provided with a ring tone speaker and a receiver for receiving a sound individually, it has become an obstacle in the desire for reduction in size and weight, and improvement is required. On the other hand, conventionally, in order to reduce the volume and weight of a mobile communication terminal and to reduce the size and weight, a speaker unit that outputs a ringing tone of a predetermined size from one side and a predetermined unit from the other side A receiver unit that outputs a sound of a magnitude, a frame that symmetrically accommodates the speaker unit and the receiver unit, and a receiver that is connected to the frame and to which an electrical signal is applied are combined. A speaker system has been proposed (see, for example, Patent Document 1).

JP 2002-58094 A

  However, in the speaker system described in Patent Document 1, an upper yoke and a lower yoke are symmetrically formed on both surfaces of a double yoke disposed at the center of the frame, and a magnet and a pole each made of a permanent magnet are provided in each yoke. A magnetic circuit composed of pieces, a voice coil, and a diaphragm are arranged. In other words, in terms of combining one frame that has been conventionally required, it is possible to reduce the size and weight somewhat, but substantially requires two magnetic circuits and two diaphragms. However, it is not always sufficient from the viewpoint of size reduction or weight reduction.

  On the other hand, in a conventional speaker system mounted on a mobile phone or the like, this space is sacrificed at the expense of a volume space portion (speaker back side volume space) that is acoustically connected to the opposite side of the speaker sound generation side in order to reduce the size. Is small. Therefore, there is a problem that the low frequency response does not increase.

  The present invention has been made in view of the above, and achieves a speaker function and a receiver function with a configuration including one electroacoustic transducer and a housing for housing the same, thereby reducing costs. In addition, an electroacoustic transducer is provided that can enhance bass by providing a port in the volumetric space (speaker back side volumetric space) that is acoustically connected to the side opposite to the sounding side of the electroacoustic transducer. It is intended to do.

  In order to solve the above-described problems and achieve the object, an electroacoustic transducer according to claim 1 of the present invention houses an electroacoustic transducer that converts an electrical signal into sound, an electroacoustic transducer, A first volume space portion acoustically connected to the sound generation side of the acoustic transducer, and a housing forming a second volume space portion acoustically connected to the opposite side of the sound generation side of the electroacoustic transducer. The body has a first sound emitting hole that allows the first volume space portion to communicate with the speaker function side external space, and the electroacoustic transducer functions as a speaker, and the first volume space portion is opposite to the speaker function side external space. A second sound emitting hole that allows the electroacoustic transducer to function as a receiver is formed, and a port having a predetermined length that communicates the second volume space portion to the external space. It is specially provided To.

  Hereinafter, embodiments of the electroacoustic transducer according to the present invention will be described in detail. Note that the present invention is not limited to the embodiments. Below, the outline and features of the electroacoustic transducer of the present invention will be described as embodiments, and then examples relating to the electroacoustic transducer will be described.

[Embodiment 1]
FIG. 1 is a cross-sectional view of the electroacoustic transducer according to Embodiment 1 of the present invention. In FIG. 1, an electroacoustic transducer 40 includes an electroacoustic transducer 10 that converts an electrical signal into sound and a housing 20 that houses the electroacoustic transducer 10. The housing 20 forms two volume space portions, a first volume space portion 31 and a second volume space portion 32, around the electroacoustic transducer 10. The first volume space 31 is formed acoustically connected to the sound generation side of the electroacoustic transducer 10. On the other hand, the second volume space 32 is acoustically connected to the opposite side of the sound generation side of the electroacoustic transducer 10. The first volume space 31 communicates with the speaker function-side external space A, which is a space on one side of the apparatus, through the first sound emission holes 22 a formed in the housing 20. The second sound emitting hole 24a formed on the opposite side communicates with the receiver function side external space B that is the space on the opposite side of the apparatus. With this configuration, the sound emitted from the sound generation side of the electroacoustic transducer 10 is emitted from the first sound emission hole 22a, and the electroacoustic transducer 10 functions as a speaker. The emitted sound is emitted from the second sound emitting hole 24a, and the electroacoustic transducer 10 functions as a receiver. Thus, with a simple configuration of one electroacoustic transducer 10 and a housing 20 that accommodates it, the single electroacoustic transducer 10 realizes a speaker function and a receiver function that face opposite sides. And cost reduction can be achieved.

  On the other hand, the second volume space 32 that is acoustically connected to the opposite side to the sounding side of the electroacoustic transducer 10 communicates with the external space via a cylindrical port 30 having a predetermined length provided in the housing 20. ing. The cylindrical port 30 is designed so that the phase of the sound radiated from the port 30 is inverted to the same phase as the phase of the sound radiated from the sounding side of the electroacoustic transducer 10. With this configuration, the low frequency response can be extended without increasing the volume of the second volume space portion 32, so that the size of the apparatus can be reduced and the bass can be enhanced.

  The sound generation direction of the electroacoustic transducer 10 is directed to the speaker function side external space A side. With this configuration, the sound emitted from the electroacoustic transducer 10 is emitted to the speaker function side external space A by going straight as it is. As a result, the generated sound volume can be increased with an easy configuration when the apparatus functions as a speaker.

  Further, the port 30 extends in a direction orthogonal to the central axis direction of the electroacoustic transducer 10. With this configuration, the port 30 that requires a predetermined length is oriented in a direction orthogonal to the central axis direction of the electroacoustic transducer 10, so that the size of the device 40 in the central axis direction, that is, the thickness of the device 40 is increased. It can be made small.

  Furthermore, in the first volume space 31, the cross-sectional area perpendicular to the sound emission direction of the passage 31a toward the first sound emission hole 22a is orthogonal to the sound emission direction of the passage 31b toward the second sound emission hole 24a. It is wider than the cross-sectional area. With this configuration, it is possible to easily increase the generated sound volume when the device functions as a speaker and reduce the generated sound volume when the device functions as a receiver.

  Further, the first sound emitting hole 22 a and the second sound emitting hole 24 a are formed by a plurality of through holes formed in the housing 20. With this configuration, the sound emission hole can be formed by an easy method of drilling, and foreign objects larger than the sound emission hole can be prevented from entering.

  Furthermore, the number of through holes in the first sound emitting hole 22a is larger than the number of through holes in the second sound emitting hole 24a. With this configuration, it is possible to easily realize a structure in which the generated sound volume is increased when the device functions as a speaker and the generated sound volume is decreased when the device functions as a receiver.

  FIG. 2 is a side view of a cross section of a part of the electroacoustic transducer according to the embodiment of the present invention. In FIG. 2, the entire housing 20 and a part of the electroacoustic transducer 10 are cross-sectional. The electroacoustic transducer 50 is an electroacoustic transducer 50 that is mounted on a mobile phone (not shown).

  The electroacoustic transducer 50 emits sound to the speaker function side external space A on the front side as indicated by an arrow a to function as a speaker, and as indicated by an arrow b to the receiver function side external space B on the back side. It emits sound and functions as a receiver. In the electroacoustic transducer 50, the electroacoustic transducer 10 is built in such a manner that the front side, which is the sound generation side, is directed in the direction of the speaker function side external space A. Although the sound generation direction of the device 10 will be described as the front surface, the direction of the electroacoustic transducer 50 is not limited to this).

  The electroacoustic transducer 50 includes an electroacoustic transducer 10, a housing 20 that houses the electroacoustic transducer 10, and a back volume space 32 (second volume space) formed on the back of the electroacoustic transducer 10. ) And a port 30 communicating with the terminal.

  The housing 20 includes a front support plate 21, a front side housing 22, a back side housing 23, and a back support plate 24. That is, a part of the front casing of the mobile phone is formed to extend, and is disposed in front of the front support plate 21 that supports the front surface of the electroacoustic transducer 10 and the front support plate 21, and has a substantially sectional concave shape. A front side housing 22 that is provided so as to cover the front surface of the acoustic transducer 10 and forms a front volume space portion 31 that is a first volume space portion in cooperation with the front support plate 21, and has a substantially sectional concave shape. A back-side housing 23 that covers the back of the acoustic transducer 10 and forms a back volume space 32 that is a second volume space on the back of the electroacoustic transducer 10, and a rear casing of the mobile phone The back support plate 24 is formed by extending the part and supports the electroacoustic transducer 10 via the back side housing 23.

  The electroacoustic transducer 10 generates sound from the cover 15 side. The structure of the electroacoustic transducer 10 will be described later. The electroacoustic transducer 10 is supported from the front support plate 21 by fixing the outer periphery of the cover 15 to the front support plate 21. The front support plate 21 is provided with a plurality of through holes 21a so as to allow the sound produced by the electroacoustic transducer 10 to pass therethrough. The front volume space 31 is acoustically connected to the front surface of the electroacoustic transducer 10 through the through hole 21a. A first sound emitting hole 22 a made up of a plurality of through holes is formed in a portion of the front housing 22 facing the through hole 21 a. The front volume space 31 is a flat space formed between the front support plate 21 and the front case 22 and a bar-like space that extends from one end of the space along the outer surface of the rear case 23. It is composed of And the 2nd sound emission hole 24a which consists of a some through-hole is formed in the part of the back surface support plate 24 of the part which this rod-shaped space reached. In the front volume space 31, the cross-sectional area orthogonal to the sound emission direction of the passage 31a toward the first sound emission hole 22a is wider than the cross-sectional area orthogonal to the sound emission direction of the passage 31b toward the second sound emission hole 24a. Has been.

  The back side housing 23 has a substantially concave cross section, and a back volume space 32 is formed behind the electroacoustic transducer 10. A cylindrical port 30 is connected to a side portion of the rear housing 23. The port 30 is provided between the front case 22 and the rear case 23 via the front support plate 21. The port 30 extends outward along the front support plate 21 and has a longitudinal outer surface fixed to the front support plate 21 over the entire length.

  The rear housing 23 is provided with a through hole 27 for connecting the electrode 10 a extending from the electroacoustic transducer 10 to a circuit pattern (not shown) formed on the rear support plate 24 through the conductive pair component 25. ing. The through hole 27 is sealed with a resin filled around the conductive pair component 25.

  FIG. 3 is a cross-sectional view of the electroacoustic transducer 10 of this embodiment. In FIG. 3, the electroacoustic transducer 10 is an internal magnet type electroacoustic transducer having a dome-shaped diaphragm 9. The electroacoustic transducer 10 has a frame main body 1 having a substantially thick ring plate shape. In the ring plate-shaped frame main body 1, a plurality of through holes 1 a penetrating in the direction of the central axis C of the electroacoustic transducer 10 are drilled at equal intervals in the circumferential direction. A large circular hole formed in the center of the frame main body 1 is a yoke mounting portion 1b.

  A substantially bowl-shaped yoke 3 made of a magnetic material is fixed to the yoke mounting portion 1b. A short cylindrical magnet 5 made of a permanent magnet is fixed to the center of the inner bottom portion of the yoke 3. A disc-shaped top plate 7 having an outer diameter slightly larger than the outer diameter of the magnet 5 is fixed to the main surface of the magnet 5 opposite to the yoke 3. The yoke 3, the magnet 5 and the top plate 7 form a magnetic circuit D. The magnetic circuit D forms a magnetic gap G between the upper inner peripheral surface of the yoke 3 and the outer peripheral surface of the top plate 7. Yes.

  A dome-shaped diaphragm 9 is disposed on the side of the top plate 7 opposite to the magnet 5 with a predetermined gap. The diaphragm 9 is supported from the outer peripheral edge 1 c of the frame main body 1 via the edge 11. A substantially cylindrical voice coil 13 is provided on the back surface of the diaphragm 9. The voice coil 13 is disposed so that one end thereof is connected to the back surface of the diaphragm 9 and the winding portion is positioned in the magnetic gap G. The front surface of the diaphragm 9 is in acoustic contact with the front volume space 31. Further, the back surface of the diaphragm 9, particularly the back surface of the edge 11, is in acoustic contact with the back volume space portion 32 through the through hole 1 a.

  In the electroacoustic transducer 10, after the magnet 5 is fixed on the inner bottom surface of the bowl-shaped yoke 3, the top plate 7 is fixed on the main surface of the magnet 5 to form the magnetic circuit D. The outer periphery of the constituting yoke 3 is fixed to the yoke mounting portion 1b formed on the frame main body 1, and the diaphragm 9 having the tip end of the voice coil 13 fixed to the back surface in advance is attached to the voice coil using a predetermined jig. The outer peripheral portion of the edge 11 adhered to the outer peripheral edge is adhered and fixed to the outer peripheral edge portion 1c of the frame main body 1 while maintaining 13 to be accurately held in the magnetic gap G.

  Then, the electroacoustic transducer 10 is completed by attaching the cover 15 having the sound emitting holes 15a to the front opening of the frame main body 1. The electroacoustic transducer 10 thus manufactured is housed in the housing 20 and then attached to a mobile phone (not shown).

  FIG. 4 is a graph showing the frequency characteristics of the electroacoustic transducer 50 according to the present embodiment in comparison with those in which the conventional port 30 is not provided. The vertical axis indicates the sound pressure level, and the horizontal axis indicates the frequency. In the graph, the solid line shows the frequency characteristics of the electroacoustic transducer 50 of the present embodiment in which the port 30 is provided, and the dotted line shows no frequency characteristics of the electroacoustic transducer of the same shape except for the ports. Show. As can be seen from the part indicated by the arrow in the graph, it can be seen that the electroacoustic transducer 50 of this example has an improved response in the region of 650 kHz or less.

  The electroacoustic transducer 50 configured as described above has a simple configuration of one electroacoustic transducer 10 and a housing 20 that houses the electroacoustic transducer 10, and the electroacoustic transducer 10 faces opposite sides. A speaker function and a receiver function can be realized, and cost reduction can be achieved.

  Further, the back volume space portion 32 that is acoustically connected to the opposite side to the sound generation side of the electroacoustic transducer 10 communicates with the external space via a cylindrical port 30 having a predetermined length provided in the housing 20. Yes. Therefore, since the low frequency response can be extended without increasing the volume of the back volume space 32, the apparatus 50 can be reduced in size and the bass can be enhanced.

  Further, the housing 20 is divided into a front housing 22 that covers the sound generation side of the electroacoustic transducer 10 and a back housing 23 that covers the opposite side of the sound generation of the electroacoustic transducer 10. Therefore, the electroacoustic transducer 10 can be easily accommodated in the housing 20, and the front volume space 31 and the back volume space 32 can be easily formed. Furthermore, since the port 30 is provided between the front housing 22 and the rear housing 23, the port 30 can be easily connected to the rear volume space 32.

  The sound generation direction of the electroacoustic transducer 10 is directed to the speaker function side external space A side. With this configuration, the sound emitted from the electroacoustic transducer 10 travels straight as it is and is emitted to the speaker function side external space A. As a result, the generated sound volume can be increased with an easy configuration when the apparatus functions as a speaker.

  Furthermore, since the port 30 extends in a direction orthogonal to the central axis C direction of the electroacoustic transducer 10, the size of the device 50 in the central axis C direction, that is, the thickness of the device 50 is small. be able to.

  Furthermore, the electroacoustic transducer 10 is an electroacoustic transducer on which only one dome-shaped diaphragm 9 is mounted. With this configuration, the cost can be further reduced. Further, since the diaphragm 9 is a dome shape, the size of the device 50 in the direction of the central axis C can be further reduced. Furthermore, since the electroacoustic transducer 10 is an inner magnet type, the cost can be reduced.

  Furthermore, in the front volume space 31, the cross-sectional area orthogonal to the sound emission direction of the passage 31a toward the first sound emission hole 22a is the crossing orthogonal to the sound emission direction of the passage 31b toward the second sound emission hole 24a. It is wider than the area. With this configuration, it is possible to easily realize a structure in which the generated sound volume is increased when the device functions as a speaker and the generated sound volume is decreased when the device functions as a receiver.

  Further, the first sound emitting hole 22 a and the second sound emitting hole 24 a are formed by a plurality of through holes formed in the housing 20. With this configuration, the sound emitting hole can be formed by an easy method of drilling with a drill or the like, for example, and entry of a foreign substance having a size of a predetermined shape or more can be prevented.

  Furthermore, the number of through holes in the first sound emitting hole 22a is larger than the number of through holes in the second sound emitting hole 24a. With this configuration, it is possible to easily realize a structure in which the generated sound volume is increased when the device functions as a speaker and the generated sound volume is decreased when the device functions as a receiver.

  Furthermore, the housing 20 includes a part of a casing (front support plate 21 and back support plate 24) of a mobile phone on which the device is mounted, and the electroacoustic transducer 10 includes the casing (front support plate 21). It is supported by. With this configuration, the electroacoustic transducer 10 can be firmly fixed to the mobile phone, and the housing 20 can be easily fixed. The port 30 is supported on the casing (front support plate 21) on the outer side in the longitudinal direction. With this configuration, the port can be firmly fixed.

  As described above, the speaker diaphragm and the manufacture of the speaker diaphragm according to the present invention are useful for a small and light speaker system, and in particular, an electroacoustic transducer having both a receiver and a speaker function mounted on a mobile phone or the like. Suitable for

It is a cross-sectional view of the electroacoustic transducer according to the first embodiment of the present invention. It is a side view which makes some cross sections the electroacoustic transducer of the Example of this invention. It is sectional drawing of the electroacoustic transducer of a present Example. It is a graph which shows the frequency characteristic of the electroacoustic transducer of a present Example compared with the thing in which the conventional port is not provided.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Frame main body 3 Yoke 5 Magnet 7 Top plate 9 Diaphragm 10 Electroacoustic transducer 11 Edge 13 Voice coil 15 Cover 20 Case 21 Front support plate (front casing of mobile phone)
22 Front side housing 22a First sound emitting hole 23 Back side housing 24 Rear support plate (rear casing of mobile phone)
24a 2nd sound emission hole 30 Port 31 Front volume space part (1st volume space part)
32 Back volume space (second volume space)
40, 50 Electroacoustic transducer A External space on speaker side B External space on receiver side C Center axis D Magnetic circuit G Magnetic gap

Claims (13)

An electroacoustic transducer for converting electrical signals into sound;
A first volume space that houses the electroacoustic transducer and is acoustically connected to the sounding side of the electroacoustic transducer, and a second volume space that is acoustically connected to the sounding side of the electroacoustic transducer And a housing forming
The housing communicates a first volume space portion to a speaker function side external space, and causes the electroacoustic transducer to function as a speaker, and the first volume space portion is connected to the speaker function side. A second sound emitting hole is formed to communicate with the receiver function side external space opposite to the external space, and the electroacoustic transducer functions as a receiver, and the second volume space portion communicates with the external space. An electroacoustic transducer having a port having a predetermined length. The electroacoustic transducer according to claim 1, wherein the sound generation direction of the electroacoustic transducer is directed toward the speaker function side external space. The electroacoustic transducer according to claim 1, wherein the port extends in a direction orthogonal to a central axis direction of the electroacoustic transducer. The said housing | casing is divided | segmented into the front side housing | casing which covers the sounding side of the said electroacoustic transducer, and the back side housing | casing which covers the opposite side to the sounding of the said electroacoustic transducer. 4. The electroacoustic transducer according to any one of items 1 to 3. The electroacoustic transducer according to claim 4, wherein the port is provided between the front housing and the rear housing. The electroacoustic transducer according to any one of claims 1 to 5, wherein the electroacoustic transducer has one diaphragm. In the first volume space portion, a cross-sectional area perpendicular to the sound emission direction of the passage toward the first sound emission hole is made wider than a cross-sectional area orthogonal to the sound emission direction of the passage toward the second sound emission hole. The electroacoustic transducer according to any one of claims 1 to 6, wherein: The electroacoustic transducer according to any one of claims 1 to 7, wherein the first sound emitting hole and the second sound emitting hole are a plurality of through holes formed in the casing. 9. The electroacoustic transducer according to claim 1, wherein the number of the through holes of the first sound emitting hole is larger than the number of the through holes of the second sound emitting hole. . The housing includes a part of a casing of a device on which the device is mounted,
The electroacoustic transducer according to any one of claims 1 to 9, wherein the electroacoustic transducer is supported by the casing. The electroacoustic transducer according to claim 10, wherein the port has a longitudinal outer surface supported by the casing. The electroacoustic transducer according to claim 11, wherein the port is supported by the casing over the entire length of the outer surface in the longitudinal direction. The electroacoustic transducer according to claim 10, wherein the device on which the device is mounted is a mobile phone.

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