JP2007110656A - Speaker accessory for mobile terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a speaker accessory whose weight and size are appropriate for carrying about with a mobile terminal and which can reproduce music in high quality and at a high volume level in a high frequency range to mid- to low-frequency ranges when attached to a mobile terminal. <P>SOLUTION: A speaker bond part 13 of the speaker accessory 10 has a through hole part to take in an output sound from a speaker for music 4 of a mobile telephone terminal inside the housing when the speaker for music 4 is attached. The speaker accessory 10 has an acoustic tube 11 inside the housing. The acoustic tube is formed so that a position where a through hole part of the speaker bond part 13 is provided serves as a part for sound intake 11a and a cross section area increases approximately at a fixed rate from the part for sound intake 11a toward an opening end 11b. Also the tube is bent spirally with the part for sound intake 11a as the center and the opening end 11b is exposed outside. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a speaker accessory for a mobile terminal suitable for a mobile terminal having a built-in speaker such as a mobile phone terminal.

  In recent years, mobile phone terminals have been commercialized as well as portable music players, which have the function of playing back all of one piece of music with high sound quality. In a mobile phone terminal having such a music playback function, an earphone or a built-in speaker connected to the terminal body is generally used as a playback music output device.

  By the way, conventionally, mobile phone terminals tend to be focused on being small, light, and thin, and accordingly, the size of the terminal housing is becoming smaller and thinner year by year. On the other hand, if the terminal housing is reduced in size and thickness, for example, it is not possible to secure a sufficient acoustic space when sound is output from the built-in speaker. If a sufficient acoustic space cannot be secured, the characteristics of the low frequency range are particularly sacrificed.

  For this reason, conventionally, various external speakers have been commercialized as accessories for improving insufficient acoustic characteristics in mobile phone terminals.

  Japanese Patent Laid-Open No. 2005-136895 (Patent Document 1) describes at least a part of a sound generated from a stereo speaker built in a mobile phone terminal and traveling in a direction other than the front of the terminal. A desktop holder and a viewing system provided with direction changing means for directing sound toward the front of the terminal are disclosed. According to the technique described in this publication, when listening to music or the like while watching the display screen while being held by the desktop holder, it is possible to listen to music with sufficient volume and high sound quality.

Japanese Patent Laying-Open No. 2005-1368965 (FIGS. 4, 7, and 9)

  However, since the external speaker as described above requires a power source and is heavy and large in size to be carried with a mobile phone terminal, for example, enjoy music using the external speaker on the go. There is a problem that it is inconvenient. Furthermore, in most cases, so-called horn-type speakers are adopted as external speakers, and the horn-type speakers are mainly used for high-frequency sounds, and those for mid- and low-frequency sounds are rarely released. The low frequency range will be weak and weak.

  On the other hand, according to the desktop holder described in the published patent publication of JP-A-2005-136895, a certain level of sound volume and sound quality can be obtained. However, this is a desktop holder and is almost stationary. Since it is used in a state, it is not suitable for carrying with a mobile phone terminal. In addition, this desktop holder is designed to focus on changing the direction of sound generated from the built-in speaker of the mobile phone terminal, so there is a demand for higher quality and higher volume music playback. Therefore, the development of a technology that enables music reproduction with higher quality and higher volume is awaited.

  The present invention has been proposed in view of such circumstances, and has a weight and dimensions that do not cause difficulty even when carried with a portable terminal, and has high quality and high volume from high to mid to low frequencies. An object of the present invention is to provide a portable terminal speaker accessory that enables reproduction.

  The speaker accessory for a portable terminal according to the present invention is provided with a speaker coupling portion having a through-hole portion into the housing and a through-hole portion of the speaker coupling portion, which is in contact with the speaker sound output portion of the portable terminal. The position is the sound capturing part, and the cross-sectional area is gradually changed from the sound capturing part to the opening end, and the sound capturing part is bent in a spiral shape around the sound capturing part. The above-described problems are solved by having an acoustic tube portion having a shape exposed to the outside.

  That is, according to the present invention, the acoustic tube having such a shape that the distance from the sound capturing portion to the opening end is sufficiently long and the cross-sectional area gradually changes from the sound capturing portion to the opening end. By improving the acoustic characteristics of the mid-low range and making the shape of the acoustic tube spiral, centering on the sound capturing part, a sufficient distance from the sound capturing part to the opening end is secured. However, the overall external dimensions are made compact.

  According to the speaker accessory for a portable terminal of the present invention, the weight and size do not make it difficult to carry with the portable terminal, and when attached to the portable terminal, the high-quality sound from the high sound range to the mid-low sound range and the high sound volume. Music playback is possible.

  Hereinafter, an embodiment of a speaker accessory for a portable terminal according to the present invention will be described with reference to the drawings.

  In the present embodiment, a mobile phone terminal is cited as an example of the mobile terminal of the present invention. Of course, the content described here is merely an example, and it goes without saying that the present invention is not limited to this example. .

[Appearance of mobile phone terminal]
1 and 2 show a schematic external configuration of a mobile phone terminal used as an example of an embodiment of the present invention. 1 shows a view of the mobile phone terminal 1 of the embodiment of the present invention as viewed from the front side, and FIG. 2 shows a view as viewed from the back side.

  In the cellular phone terminal 1 of the present embodiment, as shown in FIG. 1, a display 2 constituted by, for example, a liquid crystal device, a numeric keypad for inputting a telephone number, characters, etc. and other operation devices are provided on the front side. An operation unit 3 provided, a receiving speaker (not shown), a transmitting microphone, and the like are arranged. On the back side, a ringtone and a speaker for music (hereinafter referred to as a music speaker 4) are arranged.

[Speaker accessories]
Here, in the case where music playback is performed using the music speaker 4 of the mobile phone terminal 1, the mobile phone terminal 1 has a small terminal housing size and cannot secure a sufficient acoustic space. The characteristics of the range are sacrificed.

  For this reason, in the present embodiment, a speaker accessory 10 as shown in FIGS. 3 to 6 is used as an external accessory for improving the mid-low range characteristics when music is reproduced by the music speaker 4 of the mobile phone terminal 1. I have prepared it.

  3 and 4 show schematic external perspective views of the mobile phone terminal 1 and the speaker accessory 10, and FIG. 3 shows a state before the speaker accessory 10 is attached to the mobile phone terminal 1. FIG. 4 shows a state where the speaker accessory 10 is attached to the mobile phone terminal 1. FIG. 5 shows a schematic cross section of the mobile phone terminal 1 in the vicinity of the music speaker 4 and a schematic cross section of the speaker accessory 10 when the speaker accessory 10 is attached to the mobile phone terminal 1. Show. FIG. 6 shows a schematic configuration of the acoustic tube 11 provided in the housing of the speaker accessory 10.

  As shown in FIG. 3, the speaker accessory 10 of the present embodiment has a housing or the like formed of, for example, ABS (acrylonitrile butadiene styrene) resin, and the music speaker of the mobile phone terminal 1 is formed on the surface of the housing. 4 is provided with a speaker joint 13 having a through-hole substantially matched to the shape of 4. Further, as shown in FIGS. 3 and 5, the speaker joint 13 is provided with a ring-shaped rubber packing 13 a that is substantially matched with the shape of the music speaker 4, for example. The inside of the ring of the rubber packing 13 a is a through hole portion of the speaker joint portion 13.

  Here, when the speaker accessory 10 is attached to the mobile phone terminal 1, as shown in FIGS. 4 and 5, the ring-shaped rubber packing 13a of the speaker joint 13 and the music speaker 4 of the mobile phone terminal 1 are used. The outer part of the contact closely. The ring-shaped rubber packing 13a has a role of preventing sound from leaking to outside or noise from outside by enhancing the sealing between the outer shape of the music speaker 4 and the music speaker 4. Has a role of preventing displacement from the position of the through hole portion of the speaker joint portion 13. That is, when the speaker accessory 10 is attached to the mobile phone terminal 1, as shown in FIG. 5, the housing 1a of the mobile phone terminal 1 and the housing 10a of the speaker accessory 10 are substantially in contact with each other. At this time, the outer peripheral portion of the protective member 4a for protecting the front surface of the music speaker 4 and allowing the sound to pass through is in close contact with the ring of the rubber packing 13a. Therefore, when a sound is output from the music speaker 4 of the mobile phone terminal 1 in this state, the sound output from the music speaker 4 passes through the through hole portion of the speaker joint portion 13 and the speaker accessory 10 It will be radiated into the housing. The rubber packing 13a may be shaped to cover the outer portion of the music speaker 4 in a three-dimensional manner in order to further improve the sealing performance and the effect of preventing displacement.

  In addition, a spiral acoustic tube 11 is provided inside the housing of the speaker accessory 10 as shown in FIGS. 3 and 6.

  In the acoustic tube 11, the position where the through-hole portion of the speaker coupling portion 13 is arranged becomes the sound capturing portion 11a, and the cross-sectional area from the sound capturing portion 11a toward the opening end (sound emitting portion) 11b is increased. The tube portion is formed so as to gradually change (for example, increase at a substantially constant rate), and the tube portion is bent into a spiral shape with the sound capturing portion 11a as the center. That is, in the so-called hyperbolic horn shape in which the cross-sectional area gradually changes from the throat toward the opening end, the acoustic tube 11 is formed in a spiral shape with the throat portion as the center, and the opening end is outside. By making the shape to be oriented toward the center, the distance from the throat to the opening end is sufficiently long to improve the acoustic characteristics of the mid-low range, while the external shape is reduced (that is, the overall size is reduced) ). According to the speaker accessory 10 of this embodiment, the music speaker radiated into the housing through the speaker joint portion 13 by including the spiral acoustic tube 11 shown in FIGS. 3 and 6. As shown in FIG. 6, the sound of No. 4 advances from the sound taking-in part 11a through the spiral tube part to the opening end 11b, and is emitted to the outside from the opening end 11a.

  In the present embodiment, the characteristic design of the acoustic tube 11 is performed by applying the formula (1). In Equation (1), S is a cross-sectional area of the horn (acoustic tube), m is a spreading constant, x is a distance, and T is a coefficient.

S = S0 (coshmx + T * sinhmx) (1)
Further, in the present embodiment, the cutoff frequency fc of the acoustic tube 11 can be expressed by the formula (2), and the cutoff frequency fc is set to, for example, 500 Hz in order to improve the characteristics of the mid-low range, and the opening diameter Is set to 1/2 to 1/3 of the cut-off frequency fc. In equation (2), m is a spreading constant, c is the speed of sound, and π is the circumference.

fc = mc / 4π (2)
Thereby, in the present embodiment, for example, as shown in the sound pressure frequency response characteristic diagram of FIG. 7, the characteristics near the lowest resonance frequency are improved, and in the case of a single terminal (that is, only the music speaker 4). In comparison, it is possible to realize a maximum 22 dB increase in sound pressure in the bass region. In FIG. 7, the speaker of the mobile phone terminal alone (music speaker 4) has, as an example, a rated impedance of 8Ω, a rated input of 0.3 W, an output sound pressure level of 85 dB / 0.1 W / 0.1 m, and a minimum. A resonance frequency of 750 ± 150 Hz and an execution frequency band of 400 Hz to 20 kHz are used.

[Summary]
As described above, according to the speaker accessory of the present embodiment, since the spiral acoustic tube 11 described above is provided, the radiation characteristics such as the frequency characteristic and directivity of the music speaker 4 of the mobile phone terminal 1 are obtained. In addition to improving the radiation efficiency, it is possible to obtain an amplified sound, which is difficult to realize with only the music speaker 4 of the mobile phone terminal 1 and has a high sound quality with sufficient mid-low range and sufficient sound pressure. Sound can be emitted into space.

  The speaker accessory of the present embodiment has only an effect of amplifying the sound output from the music speaker 4 of the mobile phone terminal 1. For example, the mobile phone terminal 1 side performs volume adjustment, music selection, sound quality adjustment, and the like. The power supply is unnecessary because no electrical processing is performed and no amplifier is installed, and because it can be made with ABS resin, it is lightweight and easy to carry Therefore, for example, by attaching the speaker accessory to the mobile phone terminal in a room or town, high-quality music reproduction can be realized regardless of location.

  The above description of the embodiment is an example of the present invention. For this reason, the present invention is not limited to the above-described embodiment, and various modifications can be made according to the design and the like as long as they do not depart from the technical idea of the present invention.

  In the above-described embodiment, only the example of the external accessory is given. However, it is possible to realize a charging dock or cradle that can improve the acoustic characteristics of the mobile phone terminal by combining with a charging stand of the mobile phone terminal, for example. It becomes.

  In the above-described embodiment, music playback is given as an example. However, the present invention is applicable to amplification of received voice. For example, when used in a so-called videophone call, the voice of the other party of the videophone call can be clearly heard. It becomes possible to make it audible.

  Further, the speaker accessory of the present embodiment can be attached to the strap of the mobile phone terminal by further downsizing.

  Moreover, although the speaker accessory of this embodiment has given the example with which the speaker junction part 13 and the acoustic tube 11 were each made into one, for example, provided two speaker junction parts and two acoustic tubes each connected to it, If the two speaker joints are connected to the stereo music speakers of the two channels on the left and right, it is possible to support stereo sound.

  In addition, the mobile phone terminal to which the speaker accessory of the present embodiment is attached is not only a so-called straight type terminal as in the examples of FIGS. 1 and 2 but also various types of terminals such as a so-called folding type and jack knife type, or A portable terminal such as a PDA having a music reproduction output function can also be supported.

It is the schematic external view which looked at the mobile telephone terminal used by this invention embodiment from the front side. It is the schematic external view which looked at the mobile telephone terminal used by this invention embodiment from the back side. It is the external appearance perspective view which showed the state before a speaker accessory was attached to a mobile telephone terminal. It is the external appearance perspective view which showed the state in which the speaker accessory was attached to the mobile telephone terminal. FIG. 3 is a schematic cross-sectional view of the vicinity of the music speaker of the mobile phone terminal and the speaker accessory in a state where the speaker accessory is attached to the mobile phone terminal. It is a perspective view which shows schematic structure of the acoustic tube provided in the housing | casing of a speaker accessory. It is a sound pressure frequency response characteristic figure used for explanation of the acoustic characteristic at the time of using the acoustic characteristic of the cellular phone terminal simple substance of this embodiment, and a speaker accessory.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Mobile phone terminal, 1a Mobile phone terminal housing, 2 Display, 3 Operation unit, 4 Music speaker, 4a Music speaker protective member, 10 Speaker accessory, 10a Speaker accessory housing, 11 Spiral acoustic tube , 11a Sound take-in part of spiral acoustic tube, 11b Open end (sound emission part) of spiral acoustic tube, 13 Speaker joint, 13a Ring-shaped rubber packing

Claims (3)

A speaker sound output unit of the mobile terminal is brought into contact, and a speaker coupling unit provided with a through hole into the housing;
The position where the through hole portion of the speaker coupling portion is arranged is a sound capturing portion, and the cross-sectional area is gradually changed from the sound capturing portion toward the opening end. An acoustic tube part that is bent in a spiral shape around the indentation part, and the opening end is exposed to the outside; and
A speaker accessory for a portable terminal, comprising: A speaker accessory for a portable terminal according to claim 1, wherein
The speaker accessory for a portable terminal, wherein the acoustic tube portion is formed so that a cross-sectional area increases at a substantially constant rate from the sound capturing portion toward the opening end. A speaker accessory for a portable terminal according to claim 1, wherein
A speaker accessory for a portable terminal, wherein the speaker coupling portion includes a ring-shaped rubber packing in which the inside of the ring is the through hole portion.

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