The present invention relates to a loudspeaker, a loudspeaker module using the loudspeaker and an electronic apparatus such as a portable telephone unit, a communication apparatus, a game unit or the like, using the loudspeaker or the loudspeaker module.
A conventional technology is described referring to
Referring to
In the recent requirements towards small-sized and multi-functioning of the portable telephone units and other electronic appliances, the loudspeaker 10 is also requested to be still more downsized, and to have a greater freedom in the mounting disposition. It is essential to make an area of the diaphragm 7 smaller if a loudspeaker 10 is to be downsized; however, a diaphragm 7 having a reduced area accompanies a problem of reduced sound pressure level.
Among the compact-sized portable telephone units, some are further requested to be compatible with stereo-phonic signals; then a telephone unit needs to be mounted with a plurality of loudspeakers 10. In such a case, the loudspeaker 10 is requested to become more compact.
The present invention addresses to provide a loudspeaker that contributes to a further downsizing of the electronic apparatus such as a portable telephone units and the like.
A loudspeaker of the present invention comprises an enclosure having a second diaphragm disposed at an open end, and at least one sound generator acoustically coupled with the enclosure. The sound generator is provided with a first diaphragm, and an area of the second diaphragm is greater than an area of the first diaphragm. Depending on needs, the second diaphragm is divided into portions and the divided portions are connected with a flexible material, and the thickness of the second diaphragm can be varied depending on a portion.
a) is a cross sectional view of a loudspeaker in accordance with still other embodiment of the present invention.
b) is a cross sectional magnified view showing a key portion of
a) is a cross sectional view of a loudspeaker in accordance with still other embodiment of the present invention.
b) is a cross sectional magnified view showing a key portion of
a) is a cross sectional view of a loudspeaker in accordance with still other embodiment of the present invention.
b) is a cross sectional magnified view showing key portions of
c) is a cross sectional magnified view showing key portions of
a) is a cross sectional view of a module in accordance with an exemplary embodiment of the present invention.
b) is a cross sectional magnified view showing key portions of
a) is a cross sectional view of a portable telephone unit in accordance with an exemplary embodiment of the present invention.
b) is a cross sectional magnified view showing key portions of
Now in the following, exemplary embodiments of the present invention will be described with reference to the drawings.
First Embodiment
A loudspeaker in the first exemplary embodiment comprises a box 29 provided at the opening with a substantially flat second diaphragm 30, and a sound generator 40.
The sound generator 40 comprises an inner magnet type magnetic circuit 24 with a magnetized magnet 21 sandwiched by an upper plate 22 and a yoke 23. A frame 26 is connected to the yoke 23 of magnetic circuit 24, a first diaphragm 27 is bonded to the circumference of the frame 26, and the first diaphragm 27 is coupled with a voice coil 28. The voice coil 28 is inserted in a magnetic gap 25 of the magnetic circuit 24.
A box 29 is connected to the circumference of the frame 26, and the box 29 is provided with a substantially flat second diaphragm 30 bonded to the opening of the box 29. The first diaphragm 27 and the second diaphragm 30 are acoustically coupled via an enclosure 31. Area of the second diaphragm 30 in the present embodiment is greater than that of the first diaphragm 27.
In a structure in accordance with the present invention, a shape of the enclosure 31 as well as positioning and a shape of the first and the second diaphragms can be designed at a designer's option. Thus a designer will have a greater designing freedom in producing a compact portable telephone unit, while evading a degradation in the sound pressure of reproduced sound with a use of a larger-sized diaphragm.
In the above description, the sound generator 40 is described based on a dynamic electro-acoustic transducer. However, the sound generator 40 is not limited to the dynamic electro-acoustic transducer; it can be an electrostatic transducer or a piezoelectric transducer.
The second diaphragm 30 may have a thickness of 0.05–10 mm, depending on a total size of the apparatus. Thus a portable telephone unit or the like equipment can be designed to have a thinner profile.
A gap size underneath the second diaphragm 30 may be 0.01–10 mm. Thus a portable telephone unit or a larger equipment can be designed to provide a still thinner profile.
Although in the above description the box 29 and the frame 26 have been explained as discrete members, these components may be provided as an unitary body by a resin molding or the like processes. In this case, a finished sound generator provided in advance by coupling a diaphragm with a magnetic circuit 24, may be fit to the integrated resin body at a place corresponding to the frame.
Second Embodiment
A loudspeaker in accordance with a second exemplary embodiment of the present invention is described referring to
Furthermore, according to the present exemplary embodiment, a specific area among the outer surfaces of an electronic apparatus can be utilized as the second diaphragm 30. Thus highly efficient designing of an electronic apparatus can be expected.
Third Embodiment
A loudspeaker in accordance with a third exemplary embodiment is described in the following. The point of difference as compared with the first exemplary embodiment is that the second diaphragm 30 and the box 29 in the present exemplary embodiment are made of a transparent material. As a result, according to the present embodiment, the second diaphragm 30 as well as the box 29 can be seen through to the their bottom or the back. When designing, for example, a portable telephone unit in the above-described configuration, a display device or the like components can be disposed at an efficient space factor. In other words, they can be disposed not only in the surface area next to a loudspeaker or second diaphragm 30, but they can be also disposed in a space behind the loudspeaker or the second diaphragm 30. Thus, a still larger designing freedom and a portable telephone unit having a large second diaphragm 30 can be obtained in a more compact contour.
Fourth Embodiment
Referring to
An integration of a loudspeaker and a display device into module leads to a reduced number of processing steps during production, and to an effective parts supply management. These eventually contribute to a cost reduction.
Fifth Embodiment
A fifth exemplary embodiment is described with reference to
Referring to
Furthermore, it is also possible to dispose both the display device 41 and the operation section 42 in a space underneath the transparent second diaphragm 30. Thus further downsizing and a larger designing freedom of a portable telephone unit 51 can be expected.
Although the above description in the present exemplary embodiment has been made based on a portable telephone unit, the concept can be applied to, besides portable telephone unit, various kinds of electronic apparatus such as every kinds of communication equipment, a game unit, a Liquid Crystal TV receiver, a personal computer, a navigation device, and the like.
Sixth Embodiment
A loudspeaker in accordance with a sixth exemplary embodiment of the present invention is described referring to
Like in the third exemplary embodiment, the above configuration allows a designer a freedom to design a shape of the enclosure 31, where a shape and locations of the respective diaphragms can be designed at a designer's option. For example, when the sound generators 40 are disposed with a long distance between each other, as shown in
As is understood from the above description, area of the diaphragm 30 in the present preferred embodiment is greater than at least double the area of diaphragm 27 of the sound generator 40.
Thus the sound pressure of a loudspeaker is increased by the use of a large-sized diaphragm 30 and a plurality of sound generators 40. Since the space between the sound generators can be utilized by other components effectively, the compactness is not sacrificed and a loudspeaker can provide a great sound pressure in accordance with the present preferred embodiment.
The above explanation is made about an example using two sound generators, but the number of sound generator is not limited to two. For example, a diaphragm 30 may be provided with four sound generators disposed around, and one among a plurality of sound generators may be used for a buzzer, and many other modifications may be developed. When a plurality of sound generators are used, the size of individual sound generator can be reduced, which contributes to a further downsizing of an apparatus.
Seventh Embodiment
A module in accordance with a seventh exemplary embodiment of the present invention is described with reference to
The module 60 in the present preferred embodiment can be mounted in an outer case 52, as shown in
A loudspeaker module 60 may be disposed in any layouts in accordance with a function and a design, such as in a lengthwise arrangement or in a lateral arrangement in the outer case 52 of portable telephone unit 51.
Furthermore, both of the display device 41 and the operation section 42 can be disposed in a space underneath the transparent diaphragm 30. This arrangement enables a further downsizing of a portable telephone unit 51 and provides a further increased designing freedom. The operation section 42 can be operated by giving a pressing force with a finger, for example, from above the transparent second diaphragm 30.
In a structure of the present embodiment, a diaphragm 30 can be shared by a receiver, which used to be provided independently. In this configuration, a receiver sound-hole which used to be an indispensable item can be eliminated to provide a remarkably improved waterproof or drip-proof property. In addition, a broad vibration area of the large-sized diaphragm provides a wider service area.
Although the above explanation has been made based on a portable telephone unit, the concept can be applied to, besides portable telephone unit, various kinds of electronic apparatus such as a communication equipment, a game unit, an LCD TV receiver, a personal computer, a navigation device and the like.
Eighth Embodiment
An eighth exemplary embodiment of the present invention is described with reference to
Namely, with the diaphragm 30 of the embodiment 3, sounds generated from the two sound generators are sometimes mixed together causing a cross talk. This often affects the channel separation at stereophonic sound reproduction to a deteriorated stereophonic atmosphere. However, the second diaphragm 30 in accordance with the present exemplary embodiment, which is divided into two portions at substantially the middle, provides an improved channel separation during stereophonic sound reproduction.
As to the material 33 for dividing a diaphragm 30 into two portions, a silicone resin, a rubber, a thermoplastic elastomer, a foamed resin and the like may be used. Silicone resin has a superior waterproof property, and provides a stable channel separation during sound reproduction in stereo channel under a wide temperature range. Rubber materials provide a designer with a broad selection range in the flexibility. Thus, rubber is suitable when a critical adjustment of channel separation is requested. Thermoplastic elastomer is advantageous in high productivity and a reduced cost. Foamed resin has a great internal loss, which leads to a remarkable channel separation effect.
As described above, various kinds of effects can be generated by selecting a material for the flexible material 33.
When the sound generators 40 are disposed with a large distance between each other as illustrated in
When the sound generators 40 are disposed, as shown in
Furthermore, when a transparent material is used for the material 33 and the second diaphragm 30 is made of a transparent film, a display device 41 can be disposed underneath the diaphragm 30 without inviting visual hazard. Thus, the loudspeaker of the present exemplary embodiment and the display device 41 can be integrated into a module 70.
An integration of a loudspeaker and a display device into module contributes to reduce a number of process steps during the production, and to an effective parts supply management. These lead to a reduced cost.
Ninth Embodiment
A ninth exemplary embodiment of the present invention is described with reference to
Namely, the loudspeaker in the first exemplary embodiment has a difficulty in controlling the vibration mode of diaphragm 30 in some cases, and the frequency characteristics sometimes become unstable. With the structure of the present exemplary embodiment, however, the vibration mode can be controlled by changing partial thickness of the diaphragm 30. As a result, a compact loudspeaker yet having superior frequency characteristic and distortion characteristic is produced.
Also in the present exemplary embodiment, the channel separation at stereo sound reproduction can be improved by providing a long distance between the first diaphragms 27 disposed right and left as shown in
The second diaphragm 30 may be further provided with grooves 34, as shown in
It is preferred that the grooves 34 are carefully provided to halfway of the material thickness of diaphragm 30 in order not to introduce air leakage.
Furthermore, the vibration mode of diaphragm 30 can be optimized by gradually increasing its thickness from a center to an outer periphery, as shown in
Contrary to the above-described configuration, material thickness of the diaphragm 30 can be thinned gradually from the central area towards the outer periphery as shown in
Further, a display device 41 and a loudspeaker in the present embodiment can be integrated into a module 80, as shown in
The module 80 is built in a portable telephone unit or other electronic apparatus, as shown in
A loudspeaker in the present invention comprises an enclosure having a second diaphragm disposed at an open end, and at least one sound generator coupled acoustically with the enclosure. The sound generator has a first diaphragm, and the second diaphragm is characterized in that it has a greater area than that of the first diaphragm. The present invention allows a free optimization of respective diaphragms in terms of the positioning and shape, and downsizes a loudspeaker module and a portable electronic apparatus. Furthermore, the present invention provides an improved channel separation at stereo sound reproduction by a compact apparatus.
Number | Date | Country | Kind |
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2001-293804 | Sep 2001 | JP | national |
2001-354499 | Nov 2001 | JP | national |
2002-43022 | Feb 2002 | JP | national |
2002-191900 | Jul 2002 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/JP02/09926 | 9/26/2002 | WO | 00 | 8/1/2003 |
Publishing Document | Publishing Date | Country | Kind |
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WO03/028404 | 4/3/2003 | WO | A |
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