Patent Publication Number: US-2015078612-A1

Title: Structure of speaker driver

Description:
FIELD OF THE INVENTION 
     The present invention relates to a structure of speaker driver, and particular to the structure of speaker driver enhances an intensity of magnetic field and reduces a loss of magnetic flux. 
     BACKGROUND OF THE INVENTION 
     Traditionally, a shape of yoke of structure of speaker likes as basin, and a washer corresponds to a magnet to form an external ring surface. When the sound coil moves at vertical direct, since the structure does not gather magnetic lines, it results in phenomenon of magnetic leakage. The phenomenon destroys a sound generated from the speaker. 
     Taiwan Utility Model Patent No. M385181 discloses an improved speaker structure of magnetic path. The technical feature utilizes character of magnet to reduce magnetic leakage and enhances a magnetic flux density of magnetic gap. However, the above-mentioned patent does not teach and suggest the structure of present invention; the structure consists of the yoke and the washer. The above-mentioned patent also cannot reach the effect disclosed by the present invention. 
     Based on the deficiencies of the related art, the present invention provides a structure of speaker driver, the structure utilizes the yoke and the washer for enhancing an intensity of magnetic field and reducing a loss of magnetic flux so as to prevent a phenomenon of magnetic leakage. 
     SUMMARY OF THE INVENTION 
     Based on the problems as disclosed above, an objective of the present invention is to provide an improved speaker structure to solve the deficiencies of the related arts. 
     An aspect of The present invention is to provide a structure of speaker driver, it comprising a base, a drum paper, a yoke, a sound coil and a magnetic unit. The base includes an upper combining portion and a lower combining portion. The drum paper is configured to the upper combining portion and the yoke is configured to the lower combining portion. The sound coil is configured to an underside of drum paper surroundingly. The magnetic unit includes a magnet and a front plate, the magnetic unit is configured to above the yoke. Wherein an internal ring surface of yoke has a surface of first poly-magnet and a surface of second poly-magnet, the surface of first poly-magnet is closer to center of yoke than the internal ring surface, the surface of second poly-magnet rises along with the internal of yoke, a bottom of yoke also correspondingly rises to the surface of second poly-magnet; an external ring surface of front piece is more distant from center of front piece than an external ring surface of magnet. Compare to a prior art, the present invention provides a structure of speaker driver to gather magnetic lines for enhancing an intensity of magnetic field and reducing a loss of magnetic flux so as to prevent a phenomenon of magnetic leakage. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is a schematic view of a structure of speaker driver according to a preferred embodiment of the present invention; 
         FIG. 2  is schematic view of a structure of speaker driver according to a another preferred embodiment of the present invention; 
         FIG. 3  is schematic view of a structure of speaker driver according to another preferred embodiment of the present invention. 
     
    
    
     DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     To understand the objectives, features and effects of the present invention, the following detailed description of the embodiment of the present invention is provided along with the accompanied drawings to further describe the present invention in greater detail as follows. 
     With reference to  FIG. 1  for a structure of speaker driver according to a preferred embodiment of the present invention, the structure of speaker  1  includes a base  100 , a drum paper  200 , a yoke  300 , a sound coil  400  and a magnetic unit  500 . 
     The base  100  includes an upper combining portion  102  and a lower combining portion  104 . 
     The drum paper  200  is configured to the upper combining portion  102 . A plurality of camber  202  is formed from the center of the drum paper  200  to outside of the drum paper  200 . 
     The yoke  300  is configured to the lower combining portion  104 . An internal ring surface  320  of the yoke  300  includes a surface of first poly-magnet  322  and a surface of second poly-magnet  323 . The surface of first poly-magnet  322  is closer to center of yoke  300  than the internal ring surface  320 , the surface of second poly-magnet  323  rises along with the internal of yoke  300 , a bottom of yoke  300  also correspondingly rises to the surface of second poly-magnet  323 . Therefore, the thickness of surface of second poly-magnet  323  and the underside  321  are symmetric and equal. 
     The sound coil  400  is configured to an underside of drum paper  200  surroundingly, wherein, the sound coil  400  further includes a conductive coil  402 . 
     The magnetic unit  500  includes a magnet  520  and a front piece  540 . The front piece  540  is configured to above magnet  520 , and the magnet  520  is configured to above the surface of second poly-magnet  323 . Wherein, the front plate  540  is magnetic permeable. Furthermore, an external ring surface  541  of front piece  540  is more distant from center of front piece  540  than an external ring surface  521  of magnet  520 . 
     In addition, a magnetic gap  325  is formed between the external ring surface  541  of front piece  540  and the surface of first poly-magnet  322  of the yoke for positioning the sound coil  400 . Thus, performs by providing an electric power, the sound coil  400  generates a magnetic field, and performs perpendicular movements within the magnetic gap  325 , thereby moving the plurality of camber  202  of drum paper  200 . Due to the movement of sound coil  400 , the camber  202  vibrates the air and generates sound. 
     It should be appreciated that the surface of first poly-magnet  322  and the front piece  540  forces the magnetic lines generated by sound coil  400  to integrate, thus enhancing the magnetic force (Webber) within the magnetic gap  325 . On the other hand, the surface of second poly-magnet  323  and the underside  321  effectively reduces the magnetic flux (Gauss) loss during the perpendicular movements of the sound coil  400 , thus preventing magnetic loss. 
     With reference to  FIG. 2  for a structure of speaker driver according to another preferred embodiment of the present invention, the structure of speaker  1  further includes a supporting column  600 . 
     One side of the supporting column  600  is locked by the front plate  540 , and the other side of supporting column  600  is connected with the drum paper  200 . The supporting column  600  enhances the stability of the sound coil  400  in perpendicular movements, thus preventing the sound coil  400  from colliding with the yoke  300  and the magnetic unit  500  and reducing the life time of sound coil  400 . In addition, the supporting column  600  can either be stuck to the front plate  540  or be added adhesive when being locked by the front plate  540  to strengthen the stability of the two. 
     In addition, the supporting column  600  further include a dust cover  620 , the dust cover  620  covers the drum paper  200  corresponded to the supporting column  600  for preventing the dust from entering into the structure of speaker  1 . 
     With reference to  FIG. 3  for a structure of speaker driver according to another preferred embodiment of the present invention, the structure of speaker  1  further includes a wavy plate  700 . 
     One side of wavy plate  700  is configured to the base  100 , and the other side is configured to the sound coil  400 . Wherein, the wavy plate  700  maintains the sound coil  400  at a right position within the magnetic gap  325 , and enhances the stability of sound coil  400  in perpendicular movements, thus preventing the unexpected dust or an object from dropping into the yoke  300  and the magnetic unit  500 . 
     Furthermore, the structure of speaker  1  could choice to also add the supporting column  600  for enhancing the stability of the sound coil  400 , or not to add the supporting column  600 , in this embodiment, the supporting column  600  is added. 
     The abovementioned embodiments are provided to illustrate the principles and exemplary methods of manufacturing or formation method of the present invention only. The scope of the present invention shall be defined by the claims recited hereafter, and any modifications or variations to the terms or wordings recited in the claims shall be considered as their relevant equivalence and are within the scope of the present invention. The scope of the present invention shall be determined by the content of the claims recited hereafter.