JP2008141694A - Speaker device and mobile phone terminal having the same - Google Patents

Abstract

An object of the present invention is to realize an acoustic structure that ensures acceptable sound quality as a receiver while maintaining a function as a loudspeaker and further downsizing a mobile phone terminal.
A housing has a speaker opening portion 103 and a leak hole 106, the speaker opening portion 103 is provided at a position where a user of the housing 10 touches the ear, and the leak hole 106 is not blocked by the user. The resonance box 309 that seals the back side of the speaker diaphragm 311 is provided in the speaker 308, and the housing 10 is configured so that the speaker front sound is output from the speaker opening 103 and the leak hole 106. Is provided inside. This eliminates the need for a pipe that connects the speaker to the speaker opening 103 and the leak hole 106 while realizing an acoustic structure that ensures acceptable sound quality as a receiver, thereby realizing a miniaturized mobile phone terminal. .
[Selection] Figure 1

Description

  The present invention relates to a speaker device that a user listens by listening like a speaker of a mobile phone terminal, and a mobile phone terminal including the speaker device.

  Generally, the frequency band used for a call is 300 Hz to 3.4 kHz. And a person is easy to hear, so that a flat frequency response characteristic is. Specifically, if the low frequency band around 300 Hz is stronger than the high frequency band around 2 kHz, it becomes difficult to hear with a muffled sound, and conversely, if the high frequency band is strong, This makes it difficult to hear.

  When using the mobile phone terminal, the user closely contacts the mobile phone terminal with the ear in order to listen to the call voice. However, it is impossible to make a close contact without a gap. As a result, some gaps occur and sound leakage occurs. As a result, the frequency response characteristic is not flat. In particular, when sound leakage occurs, the acoustic impedance decreases and the volume of the low frequency band decreases. As a result, the call voice becomes very difficult to hear.

  In view of this, Patent Document 1 and Patent Document 2 describe a technique for improving the structure deterioration such as providing a sound emitting hole as a technique for improving characteristic deterioration caused by a gap between the ear and the mobile phone terminal.

  In Patent Document 1, as shown in FIG. 7, in order to obtain a desired call voice quality, sound radiated from the opening 71 is transmitted through a hole 72 (near the opening from the gap between the ear and the housing). In the following, a structure that goes out to a free acoustic space outside the housing via a leak hole) is described.

  In Patent Document 2, a passage (leak hole) is provided in the diameter of the measurement ear outside the transducer (speaker) to connect the space between the measurement ear and the housing and the free acoustic space outside the housing. The structure is described.

  That is, both documents describe a technique for reducing the influence of a decrease in acoustic impedance and providing a flat frequency response characteristic by providing a leak hole.

  Further, in Patent Document 3, as shown in FIG. 8, an acoustic hole 83 is provided in a surface (position) that is always exposed to the outside, separately from the opening 81 on the front surface of the speaker, and the acoustic hole 83 and the speaker are acoustically connected. A structure for connection by a tube 82 is described.

  Here, in this specification, the function of outputting a call voice (for example, about 10 mW output) on the assumption that the user listens with the ear in close contact with the housing is called a receiver function, A function of outputting a received voice by a speakerphone (for example, an output of about 0.5 W) is referred to as a loudspeaker function.

  In the loudspeaker function, it is necessary to be able to notify a user in the vicinity even in a noisy environment. For this purpose, it is necessary not only to increase the output of the speaker, but also to acoustically separate the sound emitted from the front of the speaker and the sound emitted from the back. This is because the sound emitted from the back of the speaker is opposite in phase to the sound emitted from the front of the speaker, so if the sound emitted from the back is combined with the sound emitted from the front, the sound pressure of the sound emitted from the front will deteriorate. Because it will end up.

And as shown in FIG. 6, patent document 1 describes the structure which isolate | separates from the radiated sound from a front by sealing the space where the radiated sound from the back of a speaker emits.
JP 2000-49920 A (publication date: February 18, 2000) Japanese translation of PCT publication No. 2002-501683 (publication date: January 15, 2002) JP 2003-60757 A (publication date: February 28, 2003)

  However, in the conventional configuration, it is difficult to reduce the size of the mobile phone terminal while providing the leak hole at a position where it is not blocked by the earlobe or the like.

  This is because the leak holes described in Patent Documents 1 and 2 need to be provided in the area where the ears of the housing are applied, but they must be provided outside the diameter of the speaker, so the ears are inevitably applied. It will be provided at the end of the region. This is because the possibility that the leak hole is blocked by an earlobe or the like increases.

  Further, according to the invention described in Patent Document 3, the leak hole (described as acoustic hole in Patent Document 3) is provided on a surface different from the surface on which the user hits the ear, so that the leak hole is blocked by the user. It is unlikely to be removed. However, since the housing external space and the speaker front acoustic space are connected with a pipe-like structure, if a thick pipe structure is formed inside the thin casing, it is difficult to reduce the size of the mobile phone terminal.

  Further, in order to reduce the decrease in acoustic impedance due to sound leakage, it is desirable that the size of the leak hole is large. This is because, in order to minimize the influence of a decrease in acoustic impedance due to sound leakage, it is necessary to make a structure with low acoustic impedance that is not affected in advance.

  In many cases, a speaker having a receiver function is arranged around a display device, which is generally the tip of a mobile phone terminal. Then, the installation space for the speakers is also limited. Further, in order to reduce the size, it is often difficult to arrange a plurality of speakers necessarily for the receiver function and the loudspeaker function. In such a case, at least one unit of speaker is used for both functions. As a speaker of such a shared unit, a loudspeaker function speaker is used. This is because the speaker for the receiver function is assumed to sound in the immediate vicinity of the ear, so that the output sound pressure is low and is not suitable for use of the loudspeaker function. In the loudspeaker function, it is effective to enlarge the sound emission hole in order to make the loudest sound possible. Furthermore, in order for the speaker itself to output a large volume, it is necessary to increase the diameter.

  As described above, the present invention has been made in view of the problem of how to further reduce the size of a speaker device while maintaining acceptable sound quality as a receiver. It is to implement the speaker device and the mobile phone terminal including the same.

  In order to solve the above-described problems, a speaker device according to the present invention includes a speaker that includes a speaker inside and is provided with two or more openings. It is provided at a position where the user of the body touches the ear, the other opening is provided at a position that is not blocked by the user, and the speaker is provided with a back sealing part that seals the back side of the speaker diaphragm, and the speaker It is characterized by being provided inside the casing so that front sound is radiated from the opening.

  According to said structure, since the back side of a speaker diaphragm is sealed by the back surface sealing part, the influence which the front sound of a speaker receives from a back sound is reduced. That is, the speaker front sound and the back sound are acoustically separated and do not interfere with each other, and the sound pressure deterioration of the speaker front sound can be prevented. As a result, if the sound volume is the same, the diameter of the speaker can be made smaller, and the apparatus can be miniaturized.

  Moreover, according to said structure, a speaker front sound is transmitted to the whole inside of a housing | casing except the back surface sealing part in the back side of a speaker diaphragm. Therefore, even if there is no pipe or the like connecting the front side of the speaker and the opening of the casing, the speaker front sound is transmitted to the opening of the casing. As a result, it is not necessary to have a structure in which a pipe or the like is provided, and the number of members constituting the inside of the apparatus can be reduced, so that the entire apparatus can be reduced in size.

  Further, since the front sound of the speaker is transmitted to the entire inside of the housing, the opening other than the opening provided at the position where the user touches the ear can be provided at an arbitrary position that is not blocked by the user. As a result, it is possible to reduce the influence of sound leakage and to provide the other opening for making the sound that enters the user's ear of good quality at an optimal position for downsizing the device. Play.

  Furthermore, the speaker device according to the present invention is preferably portable.

  According to another aspect of the present invention, there is provided a mobile phone terminal including the speaker device.

  The speaker device can be suitably used for a portable mobile phone terminal.

  Furthermore, the speaker device according to the present invention may share the speaker as a loudspeaker for notifying a nearby user of an incoming call notification sound or a warning sound, and a receiver speaker for outputting a call voice. preferable.

  According to the above configuration, since one speaker plays two roles of a loudspeaker and a receiver speaker, it is not necessary to provide a speaker that plays each role. Therefore, the number of speakers can be reduced.

  As a result, there is an additional effect that a miniaturized mobile phone terminal can be realized.

  As described above, in the speaker device according to the present invention, a part of the opening is provided at a position where the user touches the ear of the housing, and the other opening is provided at a position not blocked by the user. Is provided with a back sealing portion that seals the back side of the speaker diaphragm, and the speaker is provided inside the housing so that speaker front sound is radiated from the opening. A structure such as a pipe connecting the opening of the housing is not necessary, and the entire apparatus can be downsized.

  The form for implementing this invention is demonstrated using FIGS. 1-6.

  FIG. 3 shows an example in which the present invention is applied to a straight-type mobile phone terminal 100.

  As shown in FIG. 3, the mobile phone terminal 100 includes a key operation unit 101, a display unit 102, a speaker opening (opening) 103, a back housing 104, a front housing 105, and a leak hole (opening) 106. . And the housing | casing 10 is comprised by combining the back side housing 104 and the front side housing 105. FIG. In the present embodiment, as shown in FIG. 1 to be described later, a device provided with a resonance box 309 inside the housing 10 and a speaker unit 307 inside the resonance box 309 is called a speaker device.

  Next, FIG. 1 is a cross-sectional view showing the inside of the mobile phone terminal 100.

  As shown in FIG. 1, a speaker unit 307 is provided inside the housing 10. The speaker unit 307 is provided inside a resonance box (back side sealing portion) 309 that seals the back side of the diaphragm 311 of the speaker 308. A speaker 308 is provided inside the speaker unit 307. The resonance box 309 is provided in close contact with the inner end of the back housing 104. The speaker unit 307 has an end portion on the front side of the speaker fixed to the inner surface on the front side of the resonance box 309. Further, the housing 10 is provided with a speaker opening 103 on the front side of the speaker, on the opposite side of the display unit 102 from the key operation unit 101, and a leak hole 106 is provided on the side surface of the speaker.

  A speaker back hole 310 is provided on the back side of the speaker unit 307 so that the space on the back side of the diaphragm 311 of the speaker 308 can be acoustically connected to the inside of the resonance box 309. Further, as described above, the speaker unit 307 has a front end fixed to the inner surface on the front side of the resonance box 309, and the speaker back sound has a structure (sealed structure) that hardly transmits outside the resonance box 309. is there. The speaker front sound is transmitted to the entire interior of the housing 10 excluding the interior of the resonance box 309.

  FIG. 2 is a perspective view showing the appearance of the resonance box 309. The resonance box 309 includes a speaker unit 307 inside, and has a sealed structure except for a portion where the diaphragm 311 of the speaker 308 at the center of the surface is exposed. Speaker signal input terminals 304 are provided at two corners of the surface.

  Next, the flow of audio will be described.

  The audio signal is input from the signal source (not shown) via the signal line on the substrate 303 to the speaker 308 through the speaker signal input terminal 304. The speaker 308 vibrates the diaphragm 311 by the input audio signal and radiates sound to the front side and the back side of the speaker. The sound radiated to the back side is transmitted only to the inside of the resonance box 309 that is acoustically connected, and is not transmitted to the rest. A non-woven fabric or the like may be attached to adjust the acoustic impedance in the speaker back hole 310 that acoustically connects the space on the back side of the diaphragm 311 and the inside of the resonance box 309.

  On the other hand, the sound radiated to the front side is transmitted to the entire inside of the housing 10 except for the inside of the resonance box 309. The sound radiated to the front side is radiated to the outside from the speaker opening 103 and the leak hole 106. Note that a nonwoven fabric or the like may be attached to the speaker opening 103 or the leak hole 106 in order to adjust the acoustic impedance or prevent foreign matter from entering from the outside.

  Next, the measurement result of the frequency response characteristic of the cellular phone terminal device 100 of the present embodiment will be shown.

  Here, in order to measure the frequency response characteristic, there is a method using an ear simulator such as ITU-T (International Telecommunication Union Telecommunication Standardization Sector) Type 1 (IEC (International Electrotechnical Commission) 318) and Type 3.2. The ear simulator can measure the characteristic that can be finally heard by the ear. In other words, even if the sound emitted from the speaker is affected by the gap between the ear and the mobile phone terminal or the structure of the opening before reaching the ear, the frequency response characteristics of the sound finally heard by the ear can be reduced. Can be measured. Type 1 simulates a state where the ear and the housing are sealed, and Type 3.2 simulates a state where there is a gap between the ear and the housing.

  The Type 3.2 ear simulator simulates a condition in which there is a gap between the ear and the housing, and includes the effect of characteristic degradation due to the gap between the ear and the housing and the structure of the sound emission hole. It is possible to measure characteristics and loudness ratings. There are two types of Type 3.2, Low-Leak and High-Leak. The former simulates the case where the gap between the ear and the housing is small, and the latter simulates the case where the gap between the ear and the housing is large. In addition, there are differences in the outer shape, acoustic resistance, resonance frequency, Q value, and the like.

  FIG. 4 and FIG. 5 show examples of measurement results obtained when a leak hole is installed at the position shown in FIG. 4 and 5, the horizontal axis represents frequency (Hz), and the vertical axis represents measured sound volume (dB).

  FIG. 4 is a graph showing the frequency response characteristic of the Type 3.2 Low-Leak type. When only the speaker opening 103 is provided, the response characteristic 401 has a leak hole 106 in addition to the speaker opening 103. The case where it is provided is shown. The frequency response characteristics at this time can be said to have acceptable characteristics. However, the response characteristic 402 is compensated for increasing the low frequency band of the input signal level to the speaker. This is because the acoustic impedance is lowered by the leak hole 106 and the sound volume is attenuated particularly in a low frequency band, so that the band is compensated for an acceptable frequency response characteristic.

  Next, FIG. 5 is a graph showing the frequency response characteristics of the Type 3.2 High-Leak type. When only the speaker opening 103 is provided as the response characteristic 403, the response characteristic 404 is a leak hole in addition to the speaker opening 103. A case where 106 is provided is shown. As described above, the High-Leak type simulates a case where sound leakage is large. More specifically, sound leakage increases when the user's pressing force against the ear is weak, and such a case is simulated. Both the response characteristics 403 and the response characteristics 404 are degraded in the frequency response characteristics compared to the response characteristics 401 and the response characteristics 402, and the balance between the low frequency range and the high frequency range is significantly different. In particular, the deterioration is remarkable in a low frequency band. However, the response characteristic 404 is improved as compared with the response characteristic 403 so that the balance between the low frequency band and the high frequency band is balanced, indicating that the response characteristic 404 is a more preferable characteristic. That is, it can be said that the leak hole 106 reduces the deterioration of the frequency response characteristic due to the sound leakage between the ear and the housing.

  Moreover, as shown in FIG. 6, the leak hole 106 may be provided on a surface (lower surface) that faces downward when the user puts an ear on the mobile phone terminal 100 during use. In this case, the leak hole 106 is not blocked by a hand when grasping, as well as the earlobe and cheek.

  As shown in FIGS. 3 and 6, the leak hole 106 is not necessarily provided on the side surface or the lower surface of the mobile phone terminal 100. The mobile phone terminal 100 may be provided anywhere as long as it is not blocked by the user's earlobe, cheek, hand, or the like. As described above, by providing the leak hole 106 at an arbitrary position, the degree of freedom in design of the mobile phone terminal 100 is increased.

  Further, according to the present embodiment, the overall size can be reduced. This is an advantageous structure for a mobile phone whose overall size is remarkable even though the liquid crystal display as a display device has been increased in size.

  In addition, although embodiment mentioned above demonstrated the straight type | mold, this invention is not limited to the said embodiment, A various change is possible in the range shown to the claim including a folding type | mold. . That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  The speaker device of the present invention can handle the loudspeaker function and the receiver function with a single speaker, and can be further reduced in size. Therefore, the speaker device is applied to a device that is supposed to be carried, especially a mobile phone terminal that can be put in a small pocket. it can.

1, showing an embodiment of the present invention, is a cross-sectional view showing an internal structure of a mobile phone terminal. FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1, showing an embodiment of the present invention, is a perspective view showing an appearance of a resonance box including a speaker unit. 1, showing an embodiment of the present invention, is an overall view showing an external appearance of a mobile phone terminal. FIG. It is a figure which shows the call frequency response characteristic by the ear simulator Low-Leak type | mold which shows the characteristic of the sound heard by a user's ear | edge at the time of providing the leak hole in embodiment of this invention. It is a figure which shows the call frequency response characteristic by the ear simulator High-Leak type | mold which shows the characteristic of the sound which a user's ear can hear when the leak hole in embodiment of this invention is provided. The other embodiment of the present invention is shown and is an overall view showing the appearance of a mobile phone terminal. It is sectional drawing which shows a prior art and shows the separation structure of the structure of a leak hole, and the front sound and back sound of a speaker. It is a perspective view which shows a prior art and shows the structure of an acoustic hole.

Explanation of symbols

10 Case (part of speaker device)
100 Mobile phone terminal 103 Speaker opening (opening)
104 Back housing (part of housing)
105 Front housing (remaining case)
106 Leak hole (opening)
307 Speaker unit (part of the speaker device)
308 Speaker (part of speaker device)
309 Resonance box (rear sealing part) (part of speaker device)
310 Speaker rear hole 311 Diaphragm

Claims (4)

In a speaker device including a speaker and having a housing provided with two or more openings,
A part of the opening is provided at a position where the user of the housing touches the ear, and the other opening is provided at a position not blocked by the user.
The speaker is provided with a back sealing portion that seals the back side of the speaker diaphragm, and is provided inside the casing so that speaker front sound is radiated from the opening. Speaker device.   The speaker device according to claim 1, wherein the speaker device is portable.   A mobile phone terminal comprising the speaker device according to claim 1.   4. The mobile phone terminal according to claim 3, wherein the speaker is shared as a loudspeaker for notifying a nearby user of an incoming call notification sound or a warning sound and a receiver speaker for outputting a call voice.

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