Patent Publication Number: US-11032649-B2

Title: Speaker module and method for manufacturing same

Description:
FIELD OF THE PRESENT DISCLOSURE 
     The invention relates to the field of electroacoustic transducers, in particular to a speaker module and a manufacturing method thereof. 
     DESCRIPTION OF RELATED ART 
     The number of smart mobile devices is rising with the advent of the mobile internet era. Mobile phones are undoubtedly the most common and portable mobile terminal devices among many mobile devices. At present, mobile phones have extremely diverse functions, one of which is the high-quality music function, and the speaker in the mobile phone is one of the necessary conditions to realize this high-quality music function. 
     A related speaker module usually comprises a frame, a cover, a vibration system accommodated in the frame, and a magnetic circuit system that drives the vibration of the vibration system. The vibration system usually comprises a vibrating diaphragm and a voice coil that drives the vibrating diaphragm. The magnetic circuit system generally comprises a magnet and an upper magnetic plate arranged to the magnet surface with glue; flexible circuit boards are usually arranged to realize the electrical connection of the voice coil. The flexible circuit board and the upper magnetic plate are integrally injection moduled into the frame. However, in the related art, it is difficult to guarantee accuracy and reliability during injection moduling. 
     Therefore, it is necessary to provide an improved speaker module and a method for manufacturing the speaker module to solve the problems mentioned above. 
     SUMMARY OF THE PRESENT INVENTION 
     One of the major objects of the present invention is to provide a speaker module has a reasonably large lifetime. 
     In order to achieve the object mention above, the present invention discloses a speaker module comprises a frame having an accommodation space enclosed by a side wall, a magnetic circuit system accommodated in the frame, including a magnet and an upper magnetic plate attached on the magnet; and a vibration system accommodated in the frame, including a vibrating diaphragm and a voice coil for driving the vibrating diaphragm. At least one flexible circuit board electrically connected with the voice coil; wherein the upper magnetic plate and the flexible circuit board are integrally injection molded in the frame 
     Further, at least one flexible circuit board electrically connected with the voice coil; wherein the upper magnetic plate and the flexible circuit board are integrally injection molded in the frame. 
     Further, the flexible circuit board comprises an inner ring connected to the voice coil, an outer ring integrally injection-molded with the frame, and a connection ring connecting the inner ring and the outer ring; the inner ring is fixedly connected to the voice coil. 
     Further, the side wall comprises an upper surface close to the vibrating diaphragm, a lower surface far from the vibrating diaphragm, and an inner edge and an outer edge connecting the upper surface and the lower surface; the flexible circuit boards and the upper magnetic plate are arranged on a lower surface of the side wall. 
     Further, the frame is a long strip shaped structure, the upper magnetic plate is disposed along two edges of the frame parallel to a long axis of the frame, the flexible circuit board is disposed along two edges of the frame parallel to a short axis of the frame. 
     Further, the upper magnetic plate comprises a main body and a bending part bending and extending from both sides of the main body; the bending part extends and is integrally injection molded into the frame. 
     Further, the vibrating diaphragm comprises a centrally positioned dome and a suspension surrounding the dome; the speaker module further includes a second vibrating diaphragm denting in a direction away from the vibrating diaphragm and attached to the flexible circuit board on a side away from the vibrating diaphragm. 
     In order to achieve the object mention above, the present invention further discloses a method for manufacturing the speaker module as described above, comprising steps of: Step S 1 : providing a frame injection module, a pair of first molding materials and a pair of second molding materials; wherein the first molding material comprises an upper magnetic plate and a first injection gear connected to the upper magnetic plate; the second molding material comprises at least one flexible circuit board and a second injection gear connected to the flexible circuit boards; Step S 2 : positioning the first molding material and the second molding material into the frame injection module respectively; wherein the frame injection module includes a positioning pillar; the first injection gear and the second injection gear include positioning holes cooperating with the guiding pillar; for precisely positioning the first molding material and the second molding material with the frame injection module; Step S 3 : closing the frame injection module and injecting plastic material into the module for molding; Step S 4 : opening the module and taking out a semi-finished frame, cutting off the first injection gear and the second injection gear for obtaining a finished frame; Step S 5 : assembling a vibration system and a magnetic circuit system with the frame for obtaining the speaker module 
     The speaker module comprises a frame having an accommodation space, and a magnetic circuit system and a vibration system accommodated in the frame. The vibration system comprises a vibrating diaphragm and a voice coil that drives the vibration of the vibrating diaphragm. The frame comprises a side wall enclosing an accommodation space. The magnetic circuit system comprises a magnet and an upper magnetic plate arranged on the magnet with glue. The speaker module further comprises at least one flexible circuit board electrically connected with the voice coil. The upper magnetic plate and the flexible circuit board are integrally injection molded in the frame. The speaker module and the manufacturing method thereof can be used for accurate positioning and for effectively solving the problem of fixing the upper magnetic plate and the flexible circuit boards, and negative impact to the reliability of product because of falling can be prevented. 
    
    
     
       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 isometric view of a speaker module in accordance with an exemplary embodiment of the present invention. 
         FIG. 2  is a cross-sectional view of the speaker module taken along line A-A in  FIG. 1 . 
         FIG. 3  is an exploded view of the speaker module in  FIG. 1 . 
         FIG. 4  is a flow chart of a method for manufacturing the speaker module in  FIG. 1 . 
         FIG. 5  is an illustration of a first molding material used in the manufacturing method. 
         FIG. 6  is an illustration of a second molding material used in the manufacturing method. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT 
     The present disclosure will hereinafter be described in detail with reference to an 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 figure and the embodiment. It should be understood the specific embodiment described hereby is only to explain the disclosure, not intended to limit the disclosure. 
     As shown in  FIGS. 1-3 , the present invention provides an injection module which is applied to a speaker module and a speaker module  100  which is assembled through the injection module. 
     The present invention provides a speaker module  100 , which comprises a vibration system  1 , a magnetic circuit system  2 , and a frame  3  that accommodates and fixes the vibration system  1  and the magnetic circuit system  2  therein. 
     The vibration system  1  comprises a vibrating diaphragm  11  and a voice coil  12  that drives the vibration of the vibrating diaphragm  11 . The voice coil  12  is made of wound voice coil lead. The vibrating diaphragm  11  comprises a dome  111  and a suspension  112  surrounding the dome  111 . In this embodiment, the dome  111  and the suspension  112  are split structures, and the dome  111  is arranged on top of the suspension  112  with glue. An upper surface of the voice coil  12  abuts against a bottom of the suspension  112 . Of course, in alternative embodiments, the dome  111  can also be arranged at the bottom of suspension, and the dome  111  and the suspension  112  can also be integrated structure, both of which can be implemented. 
     The frame  3  comprises a side wall  31  that encloses an accommodation space. The side wall  31  comprises an upper surface  311 , a lower surface opposite to the upper surface  311 , and an inner edge  312  and an outer edge  313  connecting the upper surface  311  to the lower surface. The vibrating diaphragm  1  is attached to the upper surface  311  of the side wall  31  by glue. 
     As shown in  FIG. 3 , the speaker module  100  of the present invention further comprises at least one flexible circuit board  4  provided at the bottom of the voice coil  12  for elastically supporting the vibration system and electrically connected to the voice coil  12 . In this embodiment, the flexible circuit board  4  is integrally injection-molded and pressed by the injection module of the present invention. The flexible circuit board  4  comprises an inner ring  41  that supports the voice coil  12 , an outer ring  42  that is integrally molded with the frame  3 , and a connection ring  43  that connects the inner ring  41  and the outer ring  42 . Further, inner ring  41  is fixed and connected to voice coil  12 . Specifically, in this embodiment, two flexible circuit boards  4  are respectively arranged on both sides of the voice coil  12 . 
     The magnetic circuit system  2  comprises a magnet  21 , a magnetic conductive plate  22  arranged on the magnet  21  with glue, and a magnetic yoke  23  accommodating the magnet  21  and the magnetic conductive plate  22 . The magnet  21  comprises a main magnet  211  positioned in the center and an auxiliary magnet  212  surrounding the main magnet  211 . The magnetic conductive plate  22  comprises a pole plate  221  arranged on the surface of the main magnet  211  with glue and an upper magnetic plate  222  arranged to the surface of the auxiliary magnet  212  with glue. In this embodiment, the main magnet  211  is a rectangular permanent magnet, and is arranged in the center of the magnetic yoke  23 . Two auxiliary magnets  212 , are long strip shaped magnets arranged on both sides of main magnet  211 . Correspondingly, two upper magnetic plates are arranged on both sides of the speaker module. The upper magnetic plate  222  is integrally molded on the frame  3 . Specifically, the upper magnetic plate  222  comprises a main body  2221  and a bending part  2222  bending and extending from the body  2221  to both sides, and the bending part  2222  is extended and integrally injection-molded into the frame  3 . Specifically, in this embodiment, the upper magnetic plate  222  is integrally injection-molded and pressed by the injection module of the present invention. The magnetic conductive plate  22  is made of magnetic conductive material and is arranged to the surface of magnet  21  with glue for conducting magnetic field and convergence of the magnetic field to improve the magnetic induction performance of the product. Specifically, the magnetic yoke  23  comprises a bottom plate  231  and a side plate  232  bent and extended from the bottom plate  231 . A magnetic gap is formed between the main magnet  211  and the auxiliary magnet  212 . The voice coil  12  is inserted into the magnetic gap, and is forced to move in the magnetic gap during the energization process, which drives the vibrating diaphragm  11  to vibrate along the vertical direction. 
     In this embodiment, both the upper magnetic plate  222  and the flexible circuit board  4  are integrally injection-molded into the frame by using the injection module of the present invention, and are arranged on the lower surface of the side wall  31  of the frame  3 . In this embodiment, the frame  3  is a long strip shaped structure, the upper magnetic plate  222  is arranged along two long axis edge directions of frame  3 , and the flexible circuit board  4  is arranged in the two short axis edge directions of frame  3 . 
     Further, a second vibrating diaphragm  5  denting in a direction away from the vibrating diaphragm  11  is provided on surfaces at one side of the flexible circuit boards  4  away from the vibrating diaphragm  11 . The side plate  232  and the side wall  31  clamps an outer ring  41  that fix the flexible circuit board  4  and the second vibrating diaphragm  5 . In this way the vibration stability of the vibration system can be further improved. 
     As shown in  FIGS. 4-6 , the present invention further provides a method for manufacturing the speaker module, which comprises the following steps: 
     Step S 1 : providing a frame injection module, a first molding material and a second molding material. The first molding material comprises an upper magnetic plate  222  and a first injection gear  200  connected to the upper magnetic plate  222 , and the second molding material comprises the flexible circuit board  4  and a second injection gear  300  connected to the flexible circuit boards  4 . Two first molding material and second molding material, are respectively arranged corresponding to the positions of the upper magnetic plate and flexible circuit boards of the speaker module; 
     Step S 2 : putting the first and second molding materials into the frame injection module. The frame injection module includes a plurality of guiding pillars for positioning. The first injection gear  200  and the second injection gear  300  includes positioning holes for cooperating with the positioning pillars. By virtue of the positioning holes and the positioning pillars, the first molding material and the second molding material are precisely assembled with the frame injection module. The positioning holes comprise a first positioning hole  201  provided on the first injection gear  200  and a second positioning hole  301  provided on the second injection gear  300 ; 
     Step S 3 : closing the mold and injecting plastic material for molding. The plastic materials are selected according to actual needs, for example, any one of polyethylene (PE), polypropylene (PP), styrene-butadiene-acrylonitrile copolymer (ABS) polyvinyl chloride (PVC); 
     Step S 4 : opening the mold to take out the semi-finished frame, cutting off the first injection gear  200  and the second injection gear  300  to finish the frame  3 ; 
     Step S 5 : assembling the vibration system  1  and the magnetic circuit system  2  with the frame  3  to form the speaker module. Specifically, the step further includes steps of gluing the voice coil and spot welding of the voice coil wire, gluing the second vibrating diaphragm on the bottom of the voice coil, flipping frame  2  and gluing it with the vibrating diaphragm, and installing the magnetic circuit system after flipping again to complete the assembly of the product. Accordingly, the speaker module is manufactured. 
     A speaker module and a manufacturing method thereof is provided in present invention. The speaker module comprises a frame having an accommodation space, and a magnetic circuit system and a vibration system accommodated in the frame. The vibration system comprises a vibrating diaphragm and a voice coil that drives the vibration of the vibrating diaphragm. The frame comprises a side wall enclosing an accommodation space. The magnetic circuit system comprises a magnet and an upper magnetic plate arranged on the magnet with glue. The speaker module further comprises at least one flexible circuit board electrically connected with the voice coil. The upper magnetic plate and the flexible circuit board are integrally injection molded in the frame. The speaker module and the manufacturing method thereof can be used for accurate positioning and for effectively solving the problem of fixing the upper magnetic plate and the flexible circuit boards, and negative impact to the reliability of product because of falling can be prevented. 
     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 embodiment, 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.