Abstract:
A housing assembly of an electronic device includes an outer housing, an inner housing mounted to the outer housing, a first waterproof film positioned between the outer housing and the inner housing, and a second waterproof film spaced from the first waterproof film. The first waterproof film, the outer housing, and the inner housing cooperatively define a first cavity of the housing assembly. The second waterproof film, the inner housing, and the first waterproof film cooperatively form a second cavity of the housing assembly. The first and second waterproof films provide the housing assembly an excellent waterproof property. The electronic device using the housing assembly is also described.

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure generally relates to housing assemblies, and particularly to a housing assembly having excellent waterproof property and an electronic device using the housing assembly. 
     2. Description of Related Art 
     Electronic devices (such as mobile phones and personal digital assistants) include loudspeakers. Many loudspeakers have an IP67 (Ingress Protection Rating, 6 is a level of protection for solid, 7 is a level of protection for liquid) waterproof film attached to prevent water and/or oil from entering the loudspeaker. However, the IP67 waterproof film is not enough to prevent large amounts of water from penetrating the loudspeaker. Furthermore, the IP67 waterproof film has high acoustic impedance, which reduces a quality of the sound emitted by the loudspeaker. 
     Therefore, there is room for improvement within the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is a schematic view of an electronic device in accordance with an exemplary embodiment. 
         FIG. 2  is an exploded view of the electronic device of  FIG. 1 . 
         FIG. 3  is an enlarged view of portion III as shown in  FIG. 2 . 
         FIG. 4  is another exploded view of the electronic device of  FIG. 1 . 
         FIG. 5  is an enlarged view of portion V as shown in  FIG. 4 . 
         FIG. 6  is an enlarged view of portion VI as shown in  FIG. 4 . 
         FIG. 7  is a cross-sectional view of the electronic device of  FIG. 1  along line VII-VII. 
         FIG. 8  is a cross-sectional view of the electronic device of  FIG. 1  along line VIII-VIII. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1-2  show an exemplary embodiment of an electronic device  100  (i.e., a mobile phone) for describing the disclosure. The electronic device  100  includes a housing assembly  10 , a circuit board  20 , a mounting member  30 , a first loudspeaker  40 , a second loudspeaker  50 , at least one first waterproof film  60 , and at least one second waterproof film  70 . The circuit board  20  is caught between the housing assembly  10  and the mounting member  30 . The first loudspeaker  40  and the second loudspeaker  50  are mounted on the mounting member  30  and are received in the housing assembly  10 . The first loudspeaker  40  is positioned at one end of the circuit board  20 , while the second loudspeaker  50  is positioned at another end of the circuit board  20 . In the exemplary embodiment, there are two first waterproof films  60  and two second waterproof films  70 , all of which are received in the housing assembly  10 . 
     The housing assembly  10  may be a rear cover, for example, of the electronic device  100 . The electronic device  100  may further include a front cover (not shown) to match the housing assembly  10 , and a battery (not shown) connected to the circuit board  20  to power the electronic device  100 . 
     The housing assembly  10  includes an outer housing  11  and an inner housing  13  mounted to the outer housing  11 . The outer housing  11  defines a plurality of first sound holes  111  and a plurality of second sound holes  113 . The first sound holes  111  are defined at one end of the outer housing  11 , while the second sound holes  113  are defined at another end of the outer housing  11 . The first sound holes  111  and the second sound holes  113  allow the sounds emitted by the first loudspeaker  40  and the second loudspeaker  50 , respectively to transmit to the outside of the housing assembly  10 . 
     Also referring to  FIGS. 4-8 , the inner housing  13  defines at one end of the inner housing  13  a first receiving chamber  131  and a second receiving chamber  133  adjacent to the first receiving chamber  131 . The first receiving chamber  131  and the second receiving chamber  133  communicate with each other via a first through hole  135 . The first receiving chamber  131  communicates with the first sound holes  111 . The inner housing  13  also defines a third receiving chamber  137  at another end of the inner housing  13 . The third receiving chamber  137  communicates with the plurality of second sound holes  113 . 
     Referring to  FIGS. 2 and 5-8 , two first shoulders  138  protrude from two sidewalls of the first receiving chamber  131 . The first shoulders  138  are positioned between the first sound holes  111  and the first loudspeaker  40 . Two second shoulders  139  protrude from two sidewalls of the third receiving chamber  137 . The second shoulders  139  are positioned between the second sound holes  113  and the second loudspeaker  50 . 
     The circuit board  20  defines a first opening  21  at one end, and a second opening  23  at another end. The first opening  21  corresponds to the first receiving chamber  131  and the first sound holes  111 , and the second opening  23  corresponds to the third receiving chamber  137  and the second sound holes  113 . The first loudspeaker  40  is received in the first opening  21 , and the second loudspeaker  50  is received in the second opening  23 . 
     Referring to  FIGS. 3, 4 and 8 , the mounting member  30  includes a bottom wall  31 , a first chamber  33  near the second opening  23  of the circuit board  20 , and a second chamber  35  adjacent to the first chamber  33 . The circuit board  20  is supported by the bottom wall  31 . The first chamber  33  and the second chamber  35  communicate via a second through hole  37  (see  FIG. 8 ). The first chamber  33  and the second chamber  35  are each covered by a plate  39 . The plates  39  seal the first chamber  33  and the second chamber  35 . The plate  39  covering the first chamber  33  defines a third through hole  391 . The first chamber  33  and the third receiving chamber  137  communicate via the third through hole  391  (see  FIG. 8 ). 
     Referring to  FIGS. 2 and 3 , the first loudspeaker  40  and the second loudspeaker  50  are mounted on the bottom wall  31  of the mounting member  30  via a mounting base  41 , which electrically connects the first loudspeaker  40  and the second loudspeaker  50  to the circuit board  20 . 
     Referring to  FIG. 7 , one first waterproof film  60  is attached or adhered on the two first shoulders  138 . The first waterproof film  60  is positioned between the first shoulders  138  and the outer housing  11 , and defines a first cavity  61  with the outer housing  11 . One second waterproof film  70  is attached or adhered to the first loudspeaker  40 . The second waterproof film  70  is positioned between the first loudspeaker  40  and the two first shoulders  138 , and defines a second cavity  63  with the first waterproof film  60  and the first shoulders  138 . 
     Referring to  FIG. 8 , another first waterproof film  60  is attached or adhered on the two second shoulders  139 . The first waterproof film  60  is positioned between the second shoulders  139  and the outer housing  11 , and defines a third cavity  71  with the outer housing  11 . Another second waterproof film  70  is attached or adhered to the second loudspeaker  50 . The second waterproof film  70  is positioned between the second loudspeaker  50  and the two second shoulders  139 , and defines a fourth cavity  73  with the first waterproof film  60  and the second shoulders  139 . 
     The waterproof films  60  and  70  are made of synthetic resins or tarp (IP54, for example), which defines a plurality of micro-pores therein (not shown). The waterproof films  60  and  70  protect the loudspeakers  40  and  50  from damage by water, without reducing the quality of the sound. Since there are two waterproof films for each loudspeaker, the waterproof property of the loudspeakers  40  and  50  is enhanced. Even if water manages to penetrate the first waterproof films  60  to enter in the second cavity  63  and the fourth cavity  73 , the water cannot penetrate the second waterproof films  70 . Furthermore, when the first and second loudspeakers  40  and  50  are turned on, water in the second cavity  63  and the fourth cavity  73  is discharged out of the outer housing  11  by the vibration of the first and second loudspeakers  40  and  50 . 
     During assembly of the electronic device  100 , the circuit board  20  is mounted to the bottom wall  31  of the mounting member  30 . The two mounting bases  41  are mounted on the bottom wall  31  of the mounting member  30  at a location corresponding to the first opening  21  and the second opening  23 , respectively, and are electrically connected to the circuit board  20 . The first loudspeaker  40  covered by one second waterproof film  70  and the second loudspeaker  50  covered by another second waterproof film  70  are respectively mounted to one of the mounting bases  41 . One first waterproof film  60  is adhered to the first shoulders  138 , and another first waterproof film  60  is adhered to the second shoulders  139 . The inner housing  13  is engaged with the outer housing  11  to form the housing assembly  10 . Then, the housing assembly  10  is engaged with the mounting member  30 . As such, the first loudspeaker  40  is received in the first receiving chamber  131 , and the second loudspeaker  50  is received in the third receiving chamber  137 . 
     It is believed that the exemplary embodiment and its advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the disclosure or sacrificing all of its advantages, the examples hereinbefore described merely being preferred or exemplary embodiment of the disclosure.