Patent Publication Number: US-8526643-B2

Title: Speaker

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority benefit of U.S. provisional application Ser. No. 61/412,397, filed on Nov. 11, 2010. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this application. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to an audio device. Particularly, the invention relates to a speaker. 
     2. Description of Related Art 
     Two most direct sensory responses of mankind are visual system and hearing system. Therefore, scientists have been dedicated to develop devices or system techniques related to the visual system and the hearing system. Presently, electroacoustic speakers are mainly classified into direct and indirect radiation speakers, and according to driving methods thereof, the speakers are mainly classified into moving-coil, piezoelectric and electrostatic speakers. Whatever the speaker is, main components thereof include an electrode layer, a diaphragm and chambers. 
     In detail, the diaphragm includes an electret layer, and after a charging process, the electret layer may have a charge-maintaining effect in internal of the material. The electrode layer is adapted to receive sound source signals to attract or repulse charges of the electret layer, so as to drive the diaphragm to produce sounds. According to a current design, a single electrode layer is generally used to receive the sound source signals to drive the diaphragm to vibrate, and the sound output thereof is monotonous and lack of variety. 
     SUMMARY OF THE INVENTION 
     The invention is directed to a speaker, and a sound output thereof diversified. 
     The invention provides a speaker including a base, a diaphragm, a separating module, a first electrode set and a second electrode set. The base and a porous structure are formed a cavity. The diaphragm is disposed in the cavity and includes a first portion and a second portion. The separating module is located in the cavity and contacts the diaphragm to separate the cavity into a first chamber and a second chamber. The first chamber includes the first portion of the diaphragm, and the second chamber includes the second portion of the diaphragm. The first electrode set is disposed in the first chamber and is located at two sides of the diaphragm, and is adapted to connect a first sound source signal, such that the first portion of the diaphragm is vibrated and the first sound source signal is exported from the first chamber. The second electrode set is disposed in the second chamber and is located at two sides of the diaphragm, and is adapted to connect a second sound source signal, such that the second portion of the diaphragm is vibrated and the second sound source signal is exported from the second chamber. 
     In an embodiment of the invention, the diaphragm is an electret layer. 
     In an embodiment of the invention, the first electrode set includes a first electrode layer and a first metal thin-film electrode, and the second electrode set includes a second electrode layer and a second metal thin-film electrode. 
     In an embodiment of the invention, the first metal thin-film electrode is attached to the first portion of the diaphragm, and the second metal thin-film electrode is attached to the second portion of the diaphragm, where a space exists between the first metal thin-film electrode and the second metal thin-film electrode. 
     In an embodiment of the invention, the first metal thin-film electrode and the second metal thin-film electrode are disposed on a surface of the base, where a space exists between the first metal thin-film electrode and the second metal thin-film electrode. 
     In an embodiment of the invention, the first metal thin-film electrode is disposed between the base and the first portion of the diaphragm, and the second metal thin-film electrode is disposed between the base and the second portion of the diaphragm, where a space exists between the first metal thin-film electrode and the second metal thin-film electrode. 
     In an embodiment of the invention, the speaker further includes a plurality of supporting structures, where a part of the supporting structures supports between the first electrode set and the first portion of the diaphragm, and another part of the supporting structures supports between the second electrode set and the second portion of the diaphragm. 
     In an embodiment of the invention, the separating module includes a first separating structure and a second separating structure, where the first separating structure supports between the diaphragm and the base, and the second separating structure supports between the diaphragm and the porous structure. 
     In an embodiment of the invention, the separating module separates the first chamber and the second chamber as independent chambers, where the first portion of the diaphragm is not influenced by the second portion of the diaphragm. 
     In an embodiment of the invention, the first electrode layer has a plurality of first sound holes, and the second electrode layer has a plurality of second sound holes. 
     In an embodiment of the invention, the speaker includes two input terminals and the two input terminals are respectively connected to the first sound source signal and the second sound source signal. 
     In an embodiment of the invention, the speaker further includes a signal input terminal, at least a first signal line and at least a second signal line. The first signal line extends to internal of the speaker from the signal input terminal and is connected to the first electrode set, and transmits the first sound source signal to the first electrode set. The second signal line extends to the internal of the speaker from the signal input terminal and is connected to the second electrode set, and transmits the second sound source signal to the second electrode set. 
     In an embodiment of the invention, the first signal line and the second signal line are formed together with the first electrode set and the second electrode set. 
     In an embodiment of the invention, the first signal line and the second signal line are disposed on a part of the supporting structures. 
     According to the above descriptions, in the speaker of the invention, besides that the first electrode layer and the first metal thin-film electrode receive the first sound source signal to drive the diaphragm to vibrate, the second electrode layer and the second metal thin-film electrode further receive the second sound source signal to drive the diaphragm to vibrate. Therefore, compared to the conventional speaker that only has a single electrode layer and a single metal thin-film electrode, the speaker of the invention is more variable in sound source signal input, so as to provide the user more pleasant and high quality sound output. 
     In order to make the aforementioned and other features and advantages of the invention comprehensible, several exemplary embodiments accompanied with figures are described in detail below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
         FIG. 1  is a cross-sectional view of a speaker according to an embodiment of the invention. 
         FIG. 2  is a top view of a part of components of the speaker of  FIG. 1 . 
         FIG. 3  is a schematic diagram of a speaker having only one input terminal. 
         FIG. 4  is a cross-sectional view of a speaker according to another embodiment of the invention. 
         FIG. 5  is a cross-sectional view of a speaker according to another embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF DISCLOSED EMBODIMENTS 
       FIG. 1  is a cross-sectional view of a speaker according to an embodiment of the invention.  FIG. 2  is a top view of a part of components of the speaker of  FIG. 1 . For clarity&#39;s sake, a porous structure  150  of  FIG. 1  is not illustrated in  FIG. 2 . Referring to  FIG. 1  and  FIG. 2 , the speaker  100  of the present embodiment includes a base  110 , a diaphragm  120 , a first electrode set  130  and a second electrode set  140 . Along with different product designs, a shape of the speaker can be a square, a round, an oval and a triangle, etc. In the present embodiment, the shape of the speaker is, for example, a square or a rectangle, though the invention is not limited thereto. 
     The diaphragm  120  is disposed on the base  110 . The first electrode set  130  is disposed between the base  110  and the porous structure  150  and includes a first electrode layer  132  and a first metal thin-film electrode  134 , and a first portion  120   a  of the diaphragm  120  is located between the first electrode layer  132  and the first metal thin-film electrode  134 . The second electrode set  140  is disposed between the base  110  and the porous structure  150  and includes a second electrode layer  142  and a second metal thin-film electrode  144 , and a second portion  120   b  of the diaphragm  120  is located between the second electrode layer  142  and the second metal thin-film electrode  144 . The first electrode set  130  is adapted to receive a first sound source signal S 1  to drive the diaphragm  120  to vibrate, and the second electrode set  140  is adapted to receive a second sound source signal S 2  to drive the diaphragm  120  to vibrate. Along with different shapes of the speaker  100 , a shape of the diaphragm  120  can also be a square, a round, an oval and a triangle, etc. along with the shape of the speaker  100 . In the present embodiment, the shape of the diaphragm  120  is, for example, a square, though the invention is not limited thereto. Along with different product designs, the shape of the diaphragm  120  can also be different to the shape of the speaker  100 . 
     The first electrode layer  132 , the first metal thin-film electrode  134 , the second electrode layer  142  and the second metal thin-film electrode  144  are, for example, formed through a metal coating process, and a space exists between the first electrode layer  132  and the second electrode layer  142 , and a space exists between the first metal thin-film electrode  134  and the second metal thin-film electrode  144 . Along with different fabrication processes, the first electrode layer  132  and the second electrode layer  142  can be formed together through a photomask and metal coating process. Similarly, the first metal thin-film electrode  134  and the second metal thin-film electrode  144  can also be formed together through a photomask and metal coating process. When the first electrode layer  132  and the second electrode layer  142  are formed, the space between the first electrode layer  132  and the second electrode layer  142  can be formed together. Similarly, when the first metal thin-film electrode  134  and the second metal thin-film electrode  144  are formed, the space between the first metal thin-film electrode  134  and the second metal thin-film electrode  144  can be formed together. The first electrode layer  132 , the first metal thin-film electrode  134 , the second electrode layer  142  and the second metal thin-film electrode  144  can also be separately formed, which is not limited by the invention. 
     According to the above configuration, in the speaker  100 , besides that the first electrode layer  132  and the first metal thin-film electrode  134  receive the first sound source signal S 1  to drive the diaphragm  120  to vibrate, the second electrode layer  142  and the second metal thin-film electrode  144  further receive the second sound source signal S 2  to drive the diaphragm  120  to vibrate. Therefore, compared to the conventional speaker that only has a single electrode layer and a single metal thin-film electrode, the speaker  100  of the present embodiment is more variable in sound source signal input, so as to provide the user more pleasant and high quality sound output. 
     In detail, in the present embodiment, the diaphragm  120  is, for example, an electret layer, and a material thereof can be fluorinated ethylenepropylene (FEP), polytetrafluoethylene (PTFE), polyvinylidene fluride (PVDF), fluorine polymer, or other suitable dielectric materials. The dielectric material may include micro-scale or nanometer-scale pores, so that after the diaphragm  120  is electrized, it is able to keep static charges and piezoelectricity for a long period of time to achieve a charge-maintaining effect. When the first electrode layer  132  and the first metal thin-film electrode  134  receive the first sound source signal S 1 , the charges of the diaphragm  120  can attract or repulse the first electrode layer  132  and the first metal thin-film electrode  134 , so that the diaphragm  120  vibrates to produce sound output. Similarly, when the second electrode layer  142  and the second metal thin-film electrode  144  receive the second sound source signal S 2 , the charges of the diaphragm  120  can attract or repulse the second electrode layer  142  and the second metal thin-film electrode  144 , so that the diaphragm  120  vibrates to produce sound output. 
     Referring to  FIG. 2 , in the present embodiment, the first electrode layer  132  has a plurality of first sound holes  132   a , the second electrode layer  142  has a plurality of second sound holes  142   a , and the speaker further includes the porous structure  150 , which covers the first electrode layer  132  and the second electrode layer  142 . In this way, when the diaphragm  120  vibrates, the sound can be output to external through the first sound holes  132   a , the second sound holes  142   a  and the porous structure  150 . Moreover, the base  110  and the porous structure  150  are formed a cavity  110   a , and the first electrode layer  132 , the second electrode layer  142 , the diaphragm  120 , the first metal thin-film electrode  134  and the second metal thin-film electrode  144  are all disposed in the cavity  110   a.    
     The speaker  100  further includes a separating module, and the separating module includes a first separating structure  180   a  and a second separating structure  180   b . The first separating structure  180   a  and the second separating structure  180   b  are disposed between the base  110  and the porous structure  150 , where the first separating structure  180   a  is disposed between the porous structure  150  and the diaphragm  120 , and the second separating structure  180   b  is disposed between the diaphragm  120  and the base  110 . Along with different product designs, the first separating structure  180   a  can also be disposed between the first electrode layer  132 /the second electrode layer  142  on the porous structure  150  and the diaphragm  120 , which is not limited by the invention. The first separating structure  180   a  and the second separating structure  180   b  divide the cavity  110   a  into a first chamber  110   b  and a second chamber  110   c . The first electrode layer  132 , the first portion  120   a  of the diaphragm  120  and the first metal thin-film electrode  134  are located in the first chamber  110   b , so that when the first electrode layer  132  and the first metal thin-film electrode  134  receive the first sound source signal S 1  to drive the diaphragm  120  to vibrate, a resonant sound field is generated in the first chamber  110   b . The second electrode layer  142 , the second portion  120   b  of the diaphragm  120  and the second metal thin-film electrode  144  are located in the second chamber  110   c , so that when the second electrode layer  142  and the second metal thin-film electrode  144  receive the second sound source signal S 2  to drive the diaphragm  120  to vibrate, a resonant sound field is generated in the second chamber  110   c . The separating module is mainly used to separate the first portion  120   a  and the second portion  120   b  of the diaphragm  120  and divide the cavity  110   a  formed by the base  110  and the porous structure  150  into the first chamber  110   b  and the second chamber  110   c , so as to avoid interference between the first portion  120   a  and the second portion  120   b  of the diaphragm  120  to influence outputs of the first sound source signal S 1  and the second sound source signal S 2 . 
     In the present embodiment, the first metal thin-film electrode  134  is disposed at the first portion  120   a  of the diaphragm  120 , and the second metal thin-film electrode  144  is disposed at the second portion  120   a  of the diaphragm  120 , where the first metal thin-film electrode  134  can be disposed at the first portion  120   a  of the diaphragm  120  through an attaching or a coating method, and the second metal thin-film electrode  144  can be disposed at the second portion  120   a  of the diaphragm  120  through the attaching or the coating method. The speaker  100  further includes a supporting module, where the supporting module includes a plurality of first supporting structures  160  and a plurality of second supporting structures  170 . A position of any of the first supporting structures  160  corresponds to that of a second supporting structure  170 . A part of the first supporting structures  160  supports between the first electrode layer  132  and the first portion  120   a  of the diaphragm  120 , and the other part of the first supporting structures  160  supports between the second electrode layer  142  and the second portion  120   b  of the diaphragm  120 . A part of the second supporting structures  170  supports between the base  110  and the first metal thin-film electrode  134 , and the other part of the second supporting structures  170  supports between the base  110  and the second metal thin-film electrode  144 . A suitable distance is maintained between the base  110  and the porous structure  150  due to the support of the first supporting structures  160  and the second supporting structures  170 , so as to form the cavity  110   a . The first supporting structures  160  and the first separating structure  180   a  can be formed integrally, and the second supporting structures  170  and the second separating structure  180   b  can be formed integrally, so as to facilitate fabrication and assembling of the speaker  100 . 
     The first sound source signal S 1  and the second sound source signal S 2  of  FIG. 1  and  FIG. 2  are schematic, and an input method of the first sound source signal S 1  and the second sound source signal S 2  is introduced below with reference of  FIG. 3 . Along with different product designs, the first sound source signal S 1  and the second sound source signal S 2  can be respectively input through two input terminals of the speaker  100 , and the first sound source signal S 1  and the second sound source signal S 2  are respectively exported through the first chamber  110   b  and the second chamber  110   c . The first sound source signal S 1  and the second sound source signal S 2  can also enter the cavity  110   a  through a same input terminal of the speaker  100 , and then the first sound source signal S 1  and the second sound source signal S 2  are respectively transmitted to the first chamber  110   b  and the second chamber  110   c  along a transmission circuit designed on the supporting module. The first sound source signal S 1  is exported through the first chamber  110   b , and the second sound source signal S 2  is exported through the second chamber  110   c.    
       FIG. 3  is a schematic diagram of a speaker having only one input terminal. Referring to  FIG. 3 , the speaker  100  of the present embodiment includes a signal input terminal  190   a , at least one first signal line  190   b  (two first signal lines are illustrated) and at least one second signal line  190   c  (two first signal lines are illustrated). The first signal line  190   b  and the second signal line  190   c  respectively extend to the internal of the speaker  100  from the signal input terminal  190   a , and are respectively connected to the first electrode set  130  and the second electrode set  140 , so as to respectively transmit the first sound source signal S 1  and the second sound source signal S 2  to the first electrode set  130  and the second electrode set  140 . 
     The first signal line  190   b  and the second signal line  190   c  can be arranged in a reserved space on the top of or under the supporting structures  160  or the supporting structures  170 , so as to transmit the first sound source signal S 1  and the second sound source signal S 2  to preset positions to facilitate exporting the first sound source signal S 1  through the first chamber  110   b  and exporting the second sound source signal S 2  through the second chamber  110   c . Moreover, while the first electrode set  130  and the second electrode set  140  are formed through the coating process, the first signal line  190   b  and the second signal line  190   c  can be formed together on the vibrating film  120  at positions corresponding to the supporting structures  160  and the supporting structures  170 , so as to save a time for arranging the signal lines on the supporting structures  160  and the supporting structures  170 . 
     In the invention, configuration positions of the first metal thin-film electrode  134  and the second metal thin-film electrode  144  are not limited, which are described below with reference of  FIG. 4  and  FIG. 5 . 
       FIG. 4  is a cross-sectional view of a speaker according to another embodiment of the invention. Referring to  FIG. 4 , the speaker  200  of the present embodiment includes a base  210 , a diaphragm  220 , a first electrode set  230 , a second electrode set  240 , a porous structure  250 , a plurality of first supporting structures  260 , a plurality of second supporting structures  270 , a first separating structure  280   a  and a second separating structure  280   b . The first electrode set  230  includes a first electrode layer  232  and a first metal thin-film electrode  234 , and the second electrode set  240  includes a second electrode layer  242  and a second metal thin-film electrode  244 . The first electrode set  230  is adapted to receive a first sound source signal S 3  to drive a first portion  220   a  of the diaphragm  220  to vibrate, and the second electrode set  240  is adapted to receive a second sound source signal S 4  to drive a second portion  220   b  of the diaphragm  220  to vibrate. 
     A difference between the speaker  200  of the present embodiment and the speaker  100  of  FIG. 2  is as follows. The first metal thin-film electrode  234  and the second metal thin-film electrode  244  of the present embodiment are disposed on the base  210 , where the first metal thin-film electrode  234  and the second metal thin-film electrode  244  can be disposed on the surface of the base  210  through an attaching or a coating method. A part of the second supporting structures  270  supports between the first metal thin-film electrode  234  and the first portion  220   a  of the diaphragm  220 , and the other part of the second supporting structures  270  supports between the second metal thin-film electrode  244  and the second portion  220   b  of the diaphragm  220 . The first separating structure  280   a  and the second separating structure  280   b  are combined to form a separating module, which is used to separate the first portion  220   a  and the second portion  220   b  of the diaphragm  220 , and divide a cavity  210   a  formed between the base  210  and the porous structure  250  into a first chamber and a second chamber, so as to avoid interference between the first portion  220   a  and the second portion  220   b  of the diaphragm  220  to influence outputs of the first sound source signal S 3  and the second sound source signal S 4 . 
       FIG. 5  is a cross-sectional view of a speaker according to another embodiment of the invention. Referring to  FIG. 5 , the speaker  300  of the present embodiment includes a base  310 , a diaphragm  320 , a first electrode set  330 , a second electrode set  340 , a porous structure  350 , a supporting module  360  and a separating module  380 , where the supporting module  360  includes a plurality of supporting structures. The first electrode set  330  includes a first electrode layer  332  and a first metal thin-film electrode  334 , and the second electrode set  340  includes a second electrode layer  342  and a second metal thin-film electrode  344 . The first electrode set  330  is adapted to receive a first sound source signal S 5  to drive a first portion  320   a  of the diaphragm  320  to vibrate, and the second electrode set  340  is adapted to receive a second sound source signal S 6  to drive a second portion  320   b  of the diaphragm  320  to vibrate. The separating module  380  is used to separate the first portion  320   a  and the second portion  320   b  of the diaphragm  320 , and divide a cavity  310   a  formed between the base  310  and the porous structure  350  into a first chamber and a second chamber, so as to avoid interference between the first portion  320   a  and the second portion  320   b  of the diaphragm  320  to influence outputs of the first sound source signal S 5  and the second sound source signal S 6 . 
     A difference between the speaker  300  of the present embodiment and the speaker  100  of  FIG. 2  and the speaker  200  of  FIG. 4  is as follows. The first metal thin-film electrode  334  and the second metal thin-film electrode  344  of the present embodiment are disposed between the base  310  and the diaphragm  320 , so that supporting structures are not required to be configured between the first metal thin-film electrode  334  and the base  310 , between the second metal thin-film electrode  344  and the base  310 , between the first metal thin-film electrode  334  and the diaphragm  320  and between second metal thin-film electrode  344  and the diaphragm  320 . 
     In summary, the separating module is used to divide cavity formed by the base and the porous structure into a plurality of chambers, so that a single chamber can output a different sound source signal. Taking two sound source signals as an example, besides that the first electrode layer and the first metal thin-film electrode receive the first sound source signal to drive the first portion of the diaphragm to vibrate, the second electrode layer and the second metal thin-film electrode further receive the second sound source signal to drive the second portion of the diaphragm to vibrate. Since the separating module separates the diaphragm into two portions, the first sound source signal output from the first chamber is not interfered with the second sound source signal output from the second chamber. Therefore, compared to the conventional speaker that only has a single electrode layer and a single metal thin-film electrode, the speaker of the invention is more variable in sound source signal input, so as to provide the user more pleasant and high quality sound output. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.