Abstract:
A key button mechanism and a portable electronic device using same are provided. The key button mechanism includes a key button and a capturing element detachably latching with the key button. The key button includes a key body and two spaced-apart latching hooks protruding from the same surface of the key body. The capturing element includes a main body having two assembling holes spacingly defined therethrough, each assembling hole corresponds to one of the two latching hooks of the key button, each latching hook of the key button passes through one of the two assembling holes of the capturing element and detachably latches to the capturing element.

Description:
BACKGROUND 
     1. Technical Field 
     This disclosure relates to key button mechanisms, particularly to key button mechanisms used in a portable electronic device. 
     2. Description of Related Art 
     Many portable electronic devices such as mobile phones, have housings with interior compartments for receiving printed circuit boards (PCBs) therein. The mobile phone usually includes a key button mechanism attached to an outer sidewall of the housing for implementing additional functions. Users can directly operate the key button mechanism to conveniently control the mobile phone. However, typical key button mechanisms often occupy a large space of the housing, and can be difficult to actuate. 
     Therefore, there is a room for improved in the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the embodiments 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 exemplary key button mechanism and portable electronic device using same. Moreover, in the drawings like reference numerals designate corresponding parts throughout the several views. Wherever possible, the same reference numerals are used throughout the drawings to refer to the same or like elements of an embodiment. 
         FIG. 1  shows a perspective view of a portable electronic device using an exemplary key button mechanism. 
         FIG. 2  shows an exploded partial perspective view of the portable electronic device shown in  FIG. 1 . 
         FIG. 3  is similar to  FIG. 2 , but viewed from another aspect. 
         FIGS. 4 and 5  are two partial assembled perspective view of the portable electronic device shown in  FIG. 2 . 
         FIG. 6  is a top view of the portable electronic device shown in  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION 
     The key button mechanism is assembled to one side portion of a portable electronic device such as a mobile telephone, for controlling or operating the portable electronic device conveniently as a function key. The mobile telephone described herein is a representation of the type of wireless communication device that may benefit from the exemplary embodiment. However, it is to be understood that the exemplary embodiment may be applied to any type of hand-held or portable device including, but not limited to, the following devices: radiotelephones, cordless phones, paging devices, personal digital assistants, portable computers or keyboard-based handheld devices, remote control units, and portable media players (such as an MP3 or DVD player). Accordingly, any reference herein to the mobile telephone should also be considered to apply equally to other portable electronic devices. 
       FIG. 2 ,  FIG. 4  and  FIG. 5  show an embodiment of a portable electronic device  100  incorporating a key button mechanism  50 , a switch  30  and a circuit board  40 . The key button mechanism  50  includes a key button assembly  10  and a housing  20 . The key button assembly  10  and the circuit board  40  are assembled to the housing  20 . The switch  30  is electrically mounted on the circuit board  40  and positioned between the circuit board  40  and the button assembly  10 . The switch  30  is to be triggered by pressing the corresponding key button assembly  10 , to generate an electric controlling signal transmitted to the circuit board  40  for controlling the portable electronic device  100 . 
     The key button assembly  10  includes a key button  11  and a capturing element  13 . The key button  11  includes a key body  111 , two latching hooks  113  and a stopping post  115 . The two latching hooks  113  are spaced-apart and protrude from the same surface of the key body  111  and adjacent to the distal ends of the key body  111 . The stopping post  115  protrudes from the key body  111  and is located between the two latching hooks  113 . 
     The capturing element  13  includes a main body  131 , a block  133 , a first elastic arm  135  and a second elastic arm  137 . The main body  131  includes two spaced apart assembling holes  1311 , each assembling hole  1311  adjacent to one of the ends of the main body  131 , and corresponding to the two latching hooks  113  of the key button  11 . The capturing element  13  can be attached or detached from the key button  11 , where the two latching hooks  113  of the key button  11  pass through the corresponding two assembling holes  1311  of the capturing element  13 . A resisting groove  1313  is recessed from one surface of the main body  131  and positioned between the two assembling holes  1311  corresponding to the switch  30 . An accommodating hole  1315  is defined through the main body  131  adjacent to the resisting groove  1313  and corresponding to the stopping post  115  of the key button  11 . In other exemplary embodiments, the capturing element  13  can also be a connecting element received in the housing  20  and located between the housing  20  and the key button  11 . The connecting element is configured to locate the key button  11  in the housing  20  and elastically resists the housing  20  to provide a force enabling the key button  20  to rebound from the switch  30  after the key button  11  triggers the switch  30 . 
     The block  133  protrudes from the main body  131 , adjacent to the accommodating hole  1315 . The first elastic arm  135  and the second elastic arm  137  are spaced-apart and protrude from the main body  131 , each adjacent to one of the corresponding two assembling holes  1311 . The block  133  is positioned between the first elastic arm  135  and the second elastic arm  137 . The first elastic arm  135  has a distal fixing end  1351  and defines a fixing hole  1353  through the distal fixing end  1351 . In this present exemplary embodiment, the second elastic arm  137  extends toward the first elastic arm  135  and includes a stopping portion  1371  formed at the distal end thereof. The stopping portion  1371  is located in front of the block  133  and configured to prevent the main body  131  being over pressed. Herein any reference to the term “over pressed” is defined as pressing the button too deeply. When the main body  131  of the capturing element  13  is over pressed in use toward the second elastic arm  137 , the block  133  may resist against the stopping portion  1371 . 
     The housing  20  defines an assembling groove  21  enclosed by a base wall  211 , an outer assembling wall  213  and an inner resisting wall  215  opposite to the outer assembling wall  213 . The base wall  211 , the outer assembling wall  213  and the inner resisting wall  215  form the assembling groove  21  for accommodating the key mechanism  50  within the assembling groove  21 . A fixing post  2111  perpendicularly protrudes from the base wall  211  corresponding to the fixing hole  1353  of the first elastic arm  135 . The diameter of the fixing post  2111  is slightly smaller than the fixing hole  1353 , so the first elastic arm  135  of the capturing element  13  can be detachably assembled to the fixing post  2111  and the fixing post  2111  can pass through the fixing hole  1353  of the first elastic arm  135  and elastically resists against the resisting wall  215  of the assembling groove  21 . 
     A key accommodating groove  2131  is recessed from an outer surface of the outer assembling wall  213  and is configured to receive the key button  11  therein. The inner surface of the outer assembling wall  213  defines a retaining slot  2135  communicating with the key accommodating groove  2131 . The shape of the retaining slot  2135  is slightly larger than the accommodating groove  2131 . Referring also to  FIG. 3 , two locating protrusions  2133  protrude from the outer surface of the outer assembling wall  213  and are located adjacent to the two ends of the accommodating groove  2131 , thereby forming an accommodating space with the accommodating groove  2131  for receiving the key button  11 . 
     Referring to  FIGS. 2 ,  4  and  5 , in assembly, the capturing element  13  is assembled into the assembling groove  21  of the housing  20 . The main body  131  is received within the corresponding retaining slot  2135 , and the first elastic arm  135  and the second elastic arm  137  are received within the assembling groove  21 . The distal fixing end  1351  is secured to the fixing post  2111 . The fixing post  2111  passes through the fixing hole  1353  of the first elastic arm  135 . After that, the key button  11  is assembled into the accommodating groove  2131  and is latched to the capturing element  13 . The two latching hooks  113  and the stopping post  115  of the key button  11  respectively pass through the corresponding two assembling holes  1311  and the accommodating hole  1315  of the main body  131  of the capturing element  13 . The circuit board  40  is mounted on the housing  20  with the switch  30  aligning with and accommodated within the resisting groove  1313  of the capturing element  13 . 
     Referring to  FIGS. 4-6 , in use, when pressing the key button  11 , the capturing element  13  is pushed by the key button  11  against the switch  30 . The switch  30  is triggered to generate an electric controlling signal to the circuit board  40 . Meanwhile, the first elastic arm  135  and the second elastic arm  137  are deformed to resist against the inner resisting wall  215  of the housing  20 . When the key button  11  is released, the key button  11  automatically returns to its original position by the elastic force generated by capturing element  13 . 
     It is to be understood, however, that even through numerous characteristics and advantages of the disclosure have been set forth in the foregoing description, together with details of the structure and function of the invention, 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 in which the appended claims are expressed.