Patent Publication Number: US-11665472-B2

Title: Speaker box

Description:
FIELD OF THE INVENTION 
     The present disclosure relates to the field of electro-acoustic transducers, and in particular to a speaker box. 
     BACKGROUND 
     With the advent of the mobile internet era, the number of smart mobile devices has been continuously increasing. Among various mobile devices, mobile phones are undoubtedly the most common and most portable mobile devices. Currently, the functions of mobile phones are very diverse, and one of them is the high-quality music function. Thus, speaker boxes used to play sounds are applied to current smart mobile phones in large quantities. 
     A speaker box of the related art comprises a housing and a speaker unit accommodated in the housing. The speaker unit includes a diaphragm configured to vibrate and sound. The diaphragm is spaced from the housing to form a front sound cavity therebetween. The front sound cavity and a sound transmitting channel cooperatively form a front cavity of the speaker box. However, in the speaker box of the related art, there exists apparent high-frequency resonance which results in sound distortion and noise being amplified apparently and thus affecting the objective indicators and subjective acoustic performance of a smart mobile phone applying the speaker box. 
     In order to overcome the above problem, a soundproof sponge is filled in the front cavity for absorbing sound energy or the volume of the front cavity is increased for reducing the resistance of the passage of sound and alleviating the amplification of the noise by the front cavity. However, the soundproof sponge and the housing of the front cavity are two separately formed components that are not consistent with each other, which increases the difficulty of attaching the soundproof sponge to the housing of the front cavity. Furthermore, the soundproof sponge can only be filled in the sound transmitting channel of the front cavity and the vibration absorption effect is therefore limited. 
     Therefore, it is desired to provide an improved speaker box which can overcome at least one of the above problems. 
     SUMMARY 
     Accordingly, the present disclosure is directed to a speaker box which can effectively weaken the amplification effect of the front cavity of the speaker box on noise. 
     The present disclosure provides a speaker box which comprises a housing; a speaker unit accommodated in the housing. The speaker unit comprises a diaphragm configured to vibrate and sound. The diaphragm is spaced from the housing to form a front sound cavity therebetween. The speaker box further comprises a sound transmitting channel configured to communicate the front sound cavity with outside. The front sound cavity and the sound transmitting channel cooperatively form a front cavity of the speaker box. A sound absorption layer is disposed at a portion of the housing facing the front cavity. The sound absorption layer comprises a micro-porous structure which is integrally formed with the housing via injection molding. 
     In some embodiments, the sound absorption layer is disposed at an inner surface of the sound transmitting channel. 
     In some embodiments, the housing comprises a front cover and a rear cover assembled with the front cover, the diaphragm being spaced from the front cover to form the front sound cavity therebetween. 
     In some embodiments, the diaphragm comprises a dome, a suspension part extending outwardly from the dome, and a mounting part extending outwardly from the suspension part, the mounting part being fixedly connected to the front cover. 
     In some embodiments, the sound absorption layer is disposed at a portion of the front cover facing the suspension part. 
     In some embodiments, the sound absorption layer is disposed at a portion of the front cover facing the dome. 
     In some embodiments, the sound absorption layer is disposed at an inner surface of the sound transmitting channel, a portion of the front cover facing the suspension part, and a portion of the front cover facing the dome. 
     In some embodiments, the sound absorption layer is made of foamed plastic. 
     In some embodiments, the sound absorption layer is integrally formed on the housing by overmolding or double injection molding. 
     Compared with the related art, in the speaker box of the present disclosure, the sound absorption layer is made of foamed plastic with good damping and sound absorption effects, which can effectively minimize the amplification effect of the front cavity on noise. Furthermore, the sound absorption layer is integrally formed on the surface of the housing by double injection molding or overmolding. The sound absorption layer and the housing are formed as an integral structure so that the consistency between the sound absorption layer and the housing is improved and it is easy to control the manufacturing. Unlike the related art in which the soundproof sponge can only be filled in the sound transmitting channel of the front cavity, the sound absorption layer of the present disclosure made by injection molding foam material can be formed in a wide area in the speaker box. The position of the sound absorption layer of this present disclosure is more flexible and not limited. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to explain the technical solutions of the embodiments of the present disclosure more clearly, accompanying drawings used to describe the embodiments are briefly introduced below. It is evident that the drawings in the following description are only concerned with some embodiments of the present disclosure. For those skilled in the art, in a case where no inventive effort is made, other drawings may be obtained based on these drawings. 
         FIG.  1    is an isometric view of a speaker box in accordance with Embodiment I of the present disclosure; 
         FIG.  2    illustrates the speaker box of  FIG.  1   , viewed from another aspect; 
         FIG.  3    is an exploded view of the speaker box of  FIG.  1   ; 
         FIG.  4    is a cross sectional view of the speaker box, taken along line IV-IV in  FIG.  2   ; 
         FIG.  5    is a cross sectional view of a speaker box in accordance with Embodiment 2 of the present disclosure; 
         FIG.  6    illustrates a front cover and a sound absorption layer of the speaker box of  FIG.  5   . 
         FIG.  7    is a cross sectional view of a speaker box in accordance with Embodiment 3 of the present disclosure; 
         FIG.  8    illustrates a front cover and a sound absorption layer of the speaker box of  FIG.  7   ; 
         FIG.  9    is a cross sectional view of a speaker box in accordance with Embodiment 4 of the present disclosure; and 
         FIG.  10    illustrates a front cover and a sound absorption layer of the speaker box of  FIG.  9   . 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     The technical solutions in embodiments of the present disclosure will be clearly and completely described with reference to the accompanying drawings of the present disclosure. It is evident that the elements described are only some rather than all embodiments of the present disclosure. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without making any inventive effort fall into the protection scope of the present disclosure. 
     Embodiment I 
     Referring to  FIG.  1    to  FIG.  4   , a speaker box  100  in accordance with a first exemplary embodiment of the present disclosure comprises a housing  11 , a speaker unit  13  accommodated in the housing  11 , a sound transmitting channel  15  and a sound absorption layer  17 . 
     The housing  11  comprises a front cover  111  and a rear cover  113  which is assembled with the front cover  111 . The front cover  111  and the rear cover  113  cooperatively form an accommodating space. The speaker unit  13  is accommodated in the accommodating space. 
     The speaker unit  13  comprises a diaphragm  131  configured to vibrate and sound. The diaphragm  131  comprises a dome  1311 , a suspension part  1313  extending outwardly from the dome  1311 , and a mounting part  1315  extending outwardly from the suspension part  1313 . The mounting part  1315  is fixedly connected to the front cover  111  to thereby fix the diaphragm  131  to the front cover  111 . Preferably, the dome  1311  is located at the central area of the diaphragm  131 . 
     The diaphragm  131  is spaced from the housing  11  to thereby form a front sound cavity  101  therebetween. Specifically, the diaphragm  131  is spaced from the front cover  111  to cooperatively form the front sound cavity  101  therebetween. 
     The sound transmitting channel  15  is configured to communicate the front sound cavity  101  with outside the speaker box. In this embodiment, the sound transmitting channel  15  is formed in the front cover  111 . The sound transmitting channel  15  and the front sound cavity  101  cooperatively form the front cavity  102 . 
     The sound absorption layer  17  is disposed at a portion of the housing  11  facing the front cavity  102 . The sound absorption layer  17  comprises a micro-porous structure. In some embodiments, the sound absorption layer  17  is integrally formed with the housing  11  via injection molding. 
     In this embodiment, the sound absorption layer  17  is disposed at an inner surface of the sound transmitting channel  15 . 
     Preferably, the sound absorption layer  17  is made of foamed plastic. The sound absorption layer  17  may be formed on the surface of the housing  11  via double injection molding or overmolding. 
     In this embodiment, the sound absorption layer  17  is made of foamed plastic with good damping and sound absorption effects, which is beneficial to minimize the amplification effect of the front cavity  102  on noise. Furthermore, the sound absorption layer  17  is integrally formed on the surface of the housing  11  by double injection molding or overmolding. The sound absorption layer  17  and the housing  11  are formed as an integral structure so that the consistency between the sound absorption layer  17  and the housing  11  is improved and it is easy to control the process of manufacturing. 
     Embodiment 2 
       FIG.  5    and  FIG.  6    illustrate a speaker box  200  in accordance with Embodiment 2 of the present disclosure. Referring to  FIG.  5    and  FIG.  6   , the speaker box  200  of Embodiment 2 is similar to the speaker box  100  of Embodiment 1 described above except that the position of the sound absorption layer  27  of the speaker box  200  is different from that of the sound absorption layer  17  of the speaker box  100 . 
     In this embodiment, the diaphragm  231  comprises a dome  2311  located at a central area thereof, a suspension part  2313  extending outwardly from the dome  2311 , and a mounting part  2315  extending outwardly from the suspension part  2313 . The sound absorption layer  27  is disposed at a portion of the front cover  211  corresponding to the suspension part  2313 . Specifically, the sound absorption layer  27  is aligned with the suspension part  2313  in the vibration direction of the diaphragm  231 . 
     In this embodiment, the sound absorption layer  27  disposed at the portion of the front cover  211  facing the suspension part  2313  occupies a spare space in the speaker box  200  without affecting the vibration space in the speaker box  200 . 
     Embodiment 3 
     In this embodiment,  FIG.  7    and  FIG.  8    illustrate a speaker box  300  in accordance with Embodiment 3 of the present disclosure. Referring to  FIG.  7    and  FIG.  8   , the speaker box  300  of Embodiment 3 is similar to the speaker box  100  of Embodiment 1 described above except that the position of the sound absorption layer  37  of the speaker box  200  is different from that of the sound absorption layer  17  of the speaker box  100 . 
     In this embodiment, the diaphragm  331  comprises a dome  3311  located at a central area thereof, a suspension part  3313  extending outwardly from the dome  3311 , and a mounting part  3315  extending outwardly from the suspension part  3313 . The sound absorption layer  37  is disposed at a portion of the front cover  211  corresponding to the dome  3311 . Specifically, the sound absorption layer  27  is aligned with the dome  3311  in the vibration direction of the diaphragm  231 . 
     In this embodiment, the sound absorption layer  37  disposed at the portion of the front cover  211  facing the dome  3311  has a relatively large surface area and therefore has an increased effect of sound absorption and noise reduction. 
     Embodiment 4 
     In this embodiment,  FIG.  9    and  FIG.  10    illustrate a speaker box  400  in accordance with Embodiment 4 of the present disclosure. Referring to  FIG.  9    and  FIG.  10   , the speaker box  400  of Embodiment 4 is similar to the speaker box  100  of Embodiment 1 described above except that the position of the sound absorption layer  47  of the speaker box  400  is different from that of the sound absorption layer  17  of the speaker box  100 . 
     In this embodiment, the diaphragm  431  comprises a dome  4311  located at a central area thereof, a suspension part  4313  extending outwardly from the dome  4311 , and a mounting part  4315  extending outwardly from the suspension part  4313 . 
     The sound absorption layer  47  comprises a first portion  471  disposed at the inner surface of the sound transmitting channel  45 , a second portion  473  disposed at a portion of the front cover  411  facing the suspension part  4313 , and a third portion  475  disposed at a portion of the front cover  411  facing the dome  4311 . 
     In this embodiment, the sound absorption layer  47  comprises the first portion  471 , the second portion  473  and the third portion  475  respectively disposed at different positions of the front cavity, which makes the speaker box  400  easier meet specific requirements of different products. It is easier to control and adjust the frequency of sound absorption and the amplitude of the sound wave decreasing. 
     Compared with the related art, in the speaker box of the present disclosure, the sound absorption layer is made of foamed plastic with good damping and sound absorption effects, which can effectively minimize the amplification effect of the front cavity on noise. Furthermore, the sound absorption layer is integrally formed on the surface of the housing by double injection molding or overmolding. The sound absorption layer and the housing are formed as an integral structure so that the consistency between the sound absorption layer and the housing is improved and it is easy to control the manufacturing. Unlike the related art in which the soundproof sponge can only be filled in the sound transmitting channel of the front cavity, the sound absorption layer of the present disclosure made by injection molding foam material can be formed in a wide area in the speaker box. The position of the sound absorption layer of this present disclosure is more flexible and not limited. 
     The above shows and describes the embodiments of the present disclosure. It is understandable that the embodiments above are only exemplary, and should not be interpreted as limiting the present disclosure, and those skilled in the art can make changes, modifications, replacements and deformations to the embodiments above within the scope of the present disclosure.