Patent Publication Number: US-9426578-B2

Title: Electromagnetic transducer

Description:
CROSS-REFERENCE 
     This application is a continuation-in-part of U.S. patent application Ser. No. 13/332,346, filed on Dec. 20, 2011, the content of which is hereby incorporated by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present disclosure relates to an electromagnetic transducer, and more particularly to an electromagnetic transducer with an elastic member. 
     DESCRIPTION OF RELATED ART 
     As the science-technology and society advance with high speed, greater use of the electronic devices boosts the quick development of electromagnetic transducers. Multiple functions and long life of electromagnetic transducers are required for people enjoying the technical sense of both vision and ear. 
     A related electromagnetic transducer mounted to a television includes a vibrating unit and an elastic member with a number of elastic arms for supporting the vibrating unit. When the vibrating unit is vibrating, the root of the elastic arm generally suffers greater stress than other parts thereof. And long time of vibration of the elastic arm results in mechanical fatigue, which easily causes the root broken up. 
     Therefore, it is necessary to provide a new electromagnetic transducer for solving the problems mentioned above. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an isometric exploded view of an electromagnetic transducer in accordance with an exemplary embodiment of the present disclosure; 
         FIG. 2  is an isometric assembled view of the electromagnetic transducer shown in  FIG. 1 ; 
         FIG. 3  is a partially assembled view shown in  FIG. 2 , with a periphery portion of a diaphragm of the electromagnetic transducer separated from other parts; 
         FIG. 4  is an isometric view of an elastic member of the electromagnetic transducer in accordance with an exemplary embodiment of the present disclosure shown in  FIG. 1 ; 
         FIG. 5  is an enlarged view of part V shown in  FIG. 1 ; 
         FIG. 6  is a cross-sectional view of the electromagnetic transducer taken along line VI-VI in  FIG. 2 ; 
         FIG. 7  is an isometric view of an elastic member of the electromagnetic transducer in accordance with another exemplary embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Reference will now be made to describe the exemplary embodiments of the present disclosure in detail. 
     Referring to  FIGS. 1 and 2 , an electromagnetic transducer  1  comprises a frame  10 , a diaphragm  11  assembled with the frame  10 , a pair of elastic members  12  assembled with the frame  10  and connected with the diaphragm  11 , a magnetic circuit part  14  receiving in the frame  10  and having a pair of magnetic gaps, and a pair of voice coils  13  each having one end partially inserted into the corresponding magnetic gap for driving the diaphragm  11 . The combination of the diaphragm  11  and the voice coils  13  serves as a vibrating unit and are capable of vibrating along the vibrating direction for generating sound waves. The diaphragm  11  includes a top plate  111  and a periphery portion  112  surrounding the top plate  111 . The a periphery portion  112  has an outer fringe attached to the frame  10  and an inner fringe connected to the top plate  111 . 
     Referring to  FIGS. 3-6 , each of the elastic members  12  in accordance with an exemplary embodiment of the present disclosure has a U-shaped first arm  121  attached on the top plate  111  of the diaphragm  11 , a pair of second arms  122  respectively extending outwards from the two angles of the U-shaped first arm  121  along a devious way, and a pair of position plates  123  disposed at the end of the second arms  121  and each having a hole. In other embodiment, the pair of elastic members  12  could be integrated by connecting the U-shaped first arms  121  thereof (just like the configuration shown in  FIG. 7 ). 
     The first arm  121  is disposed between the inner fringe of the periphery portion  112  and the top plate  111  of the diaphragm  11 . Therefore, the first arm  121  is capable of vibrating along with the vibrating unit. In this embodiment, the first arm  121  has a first connecting portion  1211  sandwiched between the top plate  111  of the diaphragm  11  and the inner fringe of the periphery portion  112  and a pair of second connecting portions  1212  extending bendly from the two ends of the first connecting portion  1211 , respectively. 
     The second arm  122  has a first part  126  partially attached to the frame  10  and connected to the position plates  123 , a stress-relieving portion  124  connected to the first part  126 , and a second part  125  connected to the stress-relieving portion  124 . The first part  126  has a continuous portion  1262  connected to the position plates  123  and sandwiched between the outer fringe of the periphery portion  112  and the frame  10  and a U-shaped root portion  1261  extending bendly from the continuous portion  1262  and connected to the stress-relieving portion  124 . The root portions  1261  are capable of effectively absorbing a force applied by the voice coils  13  and evening the force, so that the elastic members  12  are not subjected to deformation easily. The stress-relieving portion  124  includes a first extending portion  1241  connecting with the root portion  1261 , a second extending portion  1242  connecting with the second part  125 , a bottom portion  1243  located between and connecting with the first and second extending portions  1241 ,  1242 . The joint of the first extending portion  1241  and the root portion, and the joint of the second extending portion  1242  and the second part  125  form a reference plane P 1  which is coplanar with the plane where the first part  126  locates. The bottom portion  1243  keeps a distance from the reference plane P 1 , by which the stress-relieving portion  124  protrudes from the reference plane P 1 . 
     The first part  126  is coplanar with the second part  125  for balancing the vibration of the elastic members  12 . Preferably, the first arm  121 , the first part  126  and the second part  125  are coplanar with each other. The second part  125  of the second arm  122  is adjacent to the second connecting portion  1212  of the first arm  121  for forming a slit therebetween, thereby improving the elastic force of the elastic member  12 . The second arm  122  has a U-shaped stress-relieving portion  124  adjacent to the root portion  1261  and protrudes along the vibrating direction of the vibrating unit away from the diaphragm  11 , thereby the total height of the electromagnetic transducer  1  is reduced. 
     When the diaphragm  11  is driven to vibrate by the voice coils  13 , the first arm  121  drives the second arm  122  vibrating and results in that the first part  126  suffers greatest stress. But the stress-relieving portion  124  could enhance the flexibility of the second arm  122  and share the stress with the root portion  1261  so that the root portion  1261  is not easy to be broken. 
     Referring to  FIG. 7 , an elastic member  22  in accordance with another exemplary embodiment of the present disclosure has a pair of U-shaped first arm  221  integrated with each other, four second arms  222  respectively extending outwards from angles of the U-shaped first arms  221  along a devious way, and four position plates  223  disposed at the corresponding end of the second arms  221  and each having a hole. Each of second arms  222  has a first part  2221  attached to the frame  10 , a U-shaped root portion  2223  extending bendly from the first part  2221 , an undulate-shaped stress-relieving portion  2224  connected to the root portion  2223 , and a second part  2222  connected with the stress-relieving portion  2224  and the first arms  221 . The first part  2221 , the root portion  2223  and the second part  2222  are coplanar with each other. The second part  2222  is adjacent to the first arm  221  and forms a slit therebetween. The stress-relieving portion  2224  protrudes outwards from a plane where the first part  2221  disposed in. The undulate-shaped stress-relieving portion  2224  could enhance the flexibility of the second part  2222  and share the stress with the root portion  2223  so that the root portion  2223  is not easy to be broken. 
     In other embodiment, the pair of U-shaped first arm  221  could be separated, and the shape of the stress-relieving portion  124 , 2224  is not limited or restricted to the configuration shown in the figures, and the amount of the stress-relieving portions could be two or more. 
     While the present disclosure has been described with reference to the specific embodiments, the description of the disclosure is illustrative and is not to be construed as limiting the disclosure. Various of modifications to the present disclosure can be made to the exemplary embodiments by those skilled in the art without departing from the true spirit and scope of the disclosure as defined by the appended claims.