Patent Publication Number: US-10764687-B2

Title: Sound generator

Description:
FIELD OF THE PRESENT DISCLOSURE 
     The embodiments of the invention relate to the electroacoustic components, in particular to a sound generator used in a portable device. 
     DESCRIPTION OF RELATED ART 
     With the arrival of mobile internet era, the number of intelligent mobile devices is on the increase. While among so many mobile devices, mobile phone is undoubtedly the most common and portable mobile device. Currently, mobile phone has a great variety of functions including but not limited to high-quality music function, and a loudspeaker in the mobile phone is one of the necessary conditions for achieving such high-quality music function. 
     A sound generator usually comprises a frame, a vibration system accommodated in the frame and a magnetic circuit system driving the vibration system to vibrate. In related art, to expand the audio and realize electrical connection, a spring connected with the magnetic circuit system and the frame is usually provided; the spring of the prior art is usually provided inside the inner space of the frame and thus limited in size, causing great loss in performance, allowing no further decrease in low-frequency response F 0  of products. 
     Therefore, it is necessary to provide an improved sound generator to solve the problem above. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the exemplary embodiment can be better understood with reference to the following drawings. The components in the drawing are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. 
         FIG. 1  is an exploded view of a sound generator in accordance with an exemplary embodiment of the invention. 
         FIG. 2  an assembled view of the sound generator in  FIG. 1 . 
         FIG. 3  is an assembled view of the sound generator, but some parts thereof being removed. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT 
     The present disclosure will hereinafter be described in detail with reference to exemplary embodiment. To make the technical problems to be solved, technical solutions and beneficial effects of the present disclosure more apparent, the present disclosure is described in further detail together with the figures and the embodiment. It should be understood the specific embodiment described hereby are only to explain the disclosure, not intended to limit the disclosure. 
     As shown in  FIG. 1  and  FIG. 2 , the present invention provides a sound generator  100 , comprising a vibration system  1 , a magnetic circuit system  2 , a frame  3  accommodating and fixing the vibration system  1  and the magnetic circuit system  2 , a spring  4  connecting the magnetic circuit system  2  and the frame  3 , and a lower cover  5  assembled together with the frame  3  to complete the packaging. 
     The frame  3  has an inner accommodation space, and comprises an upper surface  31 , a lower surface opposite to the upper surface  31 , and a fixing post  32  protruding from the lower surface in a direction far away from the upper surface  31 . 
     The vibration system  1  comprises a diaphragm  11  and a voice coil  12  for driving the diaphragm  11  to vibrate to further generate sound. The voice coil  12  is formed by wrapping conductive wires. The diaphragm  11  comprises a dome  112  and a suspension  111  surrounding the dome  112 . In this embodiment, the dome  112  is attached to a top of the suspension  111 . An outer periphery of the suspension  111  is fixed on the upper surface  31  of the frame  3 . A magnetic gap is formed by the magnetic circuit system  2 , and the voice coil  12  is partially inserted into the magnetic gap. The voice coil  12  is used to interact with the magnetic fluxes produced in the magnetic gap while electrified, for driving the diaphragm  12  to vibrate along a vibration direction. 
     The magnetic circuit system  2  comprises a magnet  21 , a pole plate  22  attached to the magnet  21  and a magnetic yoke  23  accommodating the magnet  21  and the pole plate  22 . The pole plate  22  is made of magnetic conductive material for magnetic induction, magnetic field convergence to improve the magnetic inductive capacity of the products. Specifically, the magnetic yoke  23  comprises a bottom wall  231  opposite to the diaphragm  11 , a side wall  232  extending from an edge of the bottom wall  231  in a direction towards the diaphragm  11  and a support plate  233  bending and extending from the side of the side wall  232  far away from the bottom wall  231 . The bottom wall  231  of the magnetic yoke  23  is a track-type structure, the magnet  21  is a track-type magnet, the pole plate  22  has a same structure as that of the magnet  21 , with the magnetic gap formed between the magnet  21  and the wall  232  of the magnetic yoke  23 . The voice coil  12  is inserted into the magnetic gap between the magnet  21  and the side wall  232 . 
     The spring  4  is provided at a lower surface side of the frame  3 . Specifically, the spring  4  comprises a main body  41  provided at the lower surface and a support part  42  protruding and extending from the main body  41  in the direction towards the accommodation space, the support plate  233  of the magnetic yoke  23  is lapped onto the support part  42 , thus realizing supporting and fixing of the magnetic circuit system  2 . Preferably, a spacing slot  2321  corresponding to the support part  42  is provided on the side wall  232  of the magnetic yoke  23 . The main body  41  includes a first arm  41   a  located on two opposite sides of the magnetic yoke and a second arm  41   b  connected with the first arm  41   a , the first arm  41   a  and the second arm  41   b  enclosing a circle around the magnetic yoke  23 , the second arm  41   b  is fixed to the lower surface and the support part  42  extends from the inner edge  401  of the first arm  41   a  to the magnetic yoke  23 , with the first arm  41   a  spaced apart from the lower surface. The support part  42  is inserted into the spacing slot  2321 , thus realizing sufficient positioning of the product to avoid slide effectively and thus affecting reliability of the product. Specifically in this embodiment, a total of four support parts  42  are provided on the periphery of the magnetic yoke  23  respectively. Correspondingly, four spacing slots  2321  are formed. 
     As shown in  FIG. 3 , the spring  4  is an annular structure, in a direction parallel to the diaphragm. The spring  4  comprises an inner edge  401  close to the accommodation space and an outer edge  402  opposite to the inner edge  401  and far away from the accommodation space. The fixing post  32  is provided between the inner edge  401  of the spring  4  and the side wall  232 . Specifically in this embodiment, a total of four fixing posts  32  are provided on four corners of the frame  3  respectively for supporting and fixing. Correspondingly, the spring  4  is a four-corner shaped structure including four adapting structures on its inner edge, such adapting structures are provided as sleeves on the peripheral edge of the fixing post  32 . Therefore, it can achieve yielding of the fixing post and make full use of the external space of the frame, so as to expand the elastic arm of the spring to the maximum degree, thus reducing the low-frequency response of the sound generator to improve the acoustic performance. 
     Further, an electrical connector  6  is provided on the fixing post  32  for electrically connecting with an external circuit. The electrical connector  6  is a conductive spring or conductive pad. Specifically in this embodiment, the electrical connector  6  is a conductive spring, and four fixing posts  32  are provided, two of which are provided with conductive pads and the other two of which only have the function of supporting and fixing. The electrical connector  6  can be injection molded into the two of the fixing posts  32  by injection molding, and can also be inserted into the fixing post  32  in a separable structure. 
     The lower cover  5  is provided with a positioning hole  51  for accommodating the fixing post. Specifically in this embodiment, two positioning holes  51  are provided for accommodating the fixing post  32  provided with the electrical connector. Therefore, it can facilitate the connection with the external circuit. 
     The sound generator of the present invention comprises a frame with an accommodating space, a magnetic circuit system and a vibration system accommodated in the frame and a spring connecting the magnetic circuit system and the frame. The vibration system comprises a diaphragm and a voice coil for driving the diaphragm to drive. The magnetic circuit system comprises a magnetic yoke and a magnet carried by the magnetic yoke. The magnetic yoke comprises a bottom wall opposite to the diaphragm, a side wall extending from the edge of the bottom wall towards the direction of the diaphragm and a supporting plate bending and extending from the side wall towards the direction far away from the magnet. The frame comprises an upper surface close to the diaphragm and a lower surface far away from the diaphragm, the lower surface provided with a fixing post protruding towards the direction far away from the upper surface. The spring comprises a main body provided at the lower surface and a supporting part protruding and extending from the main body towards the accommodating space. The supporting plate of the magnetic yoke is lapped on the supporting part. The spring comprises an inner edge close to the accommodating space and an outer edge opposite to the inner edge and far away from the accommodation space. The fixing post is provided between the inner edge of the spring and the side wall. Compared to the relate art, the spring of the present invention can make more effective use of space, ensure the spring size, thus reducing the low-frequency response of the sound generator to further improve the acoustic performance. 
     It is to be understood, however, that even though numerous characteristics and advantages of the present exemplary embodiment have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms where the appended claims are expressed.