Patent Publication Number: US-7714246-B2

Title: Key button, key assembly using the key button and portable electronic device using the keypad assembly

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to input devices, particularly to a key button, a keypad assembly using the key button, and a portable electronic device using the keypad assembly. 
   2. Description of Related Art 
   Keypad assembly is inevitably used in a portable electronic device, such as a mobile phone, for inputting information into the device, such as control commands. 
   A typical keypad assembly often includes at least one key button therewith. A user can input information into the device simply by operating/pressing the at least one key button. Unfortunately, the user may make mistakes during operation, such as pressing the wrong key button. When this happens, additional operation is needed by the user to amend/correct such mistakes. 
   Therefore, a heretofore-unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies. 
   SUMMARY 
   In first aspect thereof, a key button is provided. The key button includes a key portion, a supporting portion, a switching portion, a pad portion, and a circuit board portion. The supporting portion has a first through hole defined therethrough. The switching portion includes at least one switching elastic sheet. The pad portion includes a base body and a protruding portion. The protruding portion is formed on the base body. The circuit board portion includes a first contacting point, a contacting sheet, and at least one second contacting point. The pad portion is located between the supporting portion and the circuit board portion with the protruding portion configured for engaging through the first through hole of the supporting portion to attach with the key portion. As the key portion is pressed towards the circuit board portion, the switching portion moves along with the pad portion so as to firstly electronically connect the contacting sheet with the at least one second contacting point via the respective switching elastic sheet. Secondly, as the key portion is further pressed, the contacting sheet further electronically connects with the first contacting point. 
   In second aspect thereof, a keypad assembly is provided. The keypad assembly includes at least one present key button. 
   In third aspect thereof, a portable electronic device is provided. The portable electronic device includes the present keypad assembly. 
   These and other aspects of the present invention will become more apparent from the following detailed description of the preferred embodiments taken in conjunction with the accompanying drawings, although variations and modifications therein may be affected without departing from the spirit and scope of the novel concepts of the disclosure. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Many aspects of the present key button, the keypad assembly using the key button, and the portable electronic device using the keypad assembly can be better understood with reference to the following drawings. These drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present key button, the keypad assembly, and the portable electronic device. Moreover, in the drawings like reference numerals designate corresponding parts throughout the several views. Wherever possible, the same reference numbers are used throughout the drawings to refer to the same or like elements of an embodiment. 
       FIG. 1  is an isometric view of a portable electronic device using a keypad assembly in accordance with a first and second embodiment, the keypad assembly including at least one key button. 
       FIG. 2  is an exploded view of one key button shown in  FIG. 1  in accordance with the first embodiment. 
       FIG. 3  is a partially cut-away view of an assembled key button in accordance with the first embodiment. 
       FIG. 4  is an exploded view of one key button shown in  FIG. 1  in accordance with the second embodiment. 
       FIG. 5  is a partially cut-away view of an assembled key button in accordance with the second embodiment. 
   

   DETAILED DESCRIPTION OF THE EMBODIMENTS 
   The present key button and keypad assembly using at least one key button are described here in conjunction with the accompanying drawings in  FIGS. 1 through 5 . The keypad assembly is suitably assembled in a portable electronic device, such as the mobile phone, the personal digital handset, or the like. 
   Referring to  FIG. 1 , the keypad assembly  20  incorporated within the portable electronic device  10  includes at least one key button  30 . The at least one key button  30  is arranged and distributed on a surface of the keypad assembly  20  in a certain pattern. 
   Referring to  FIG. 2 , the at least one key button  30  of the first embodiment each includes a key portion  32 , a supporting portion  34 , a switching portion  35 , a pad portion  36 , and a circuit board portion  38 . 
   The key portion  32  is generally rectangular and advantageously has at least one symbol (e.g., number) labeled therewith. 
   The supporting portion  34  is configured for supporting the key button  30  within the keypad assembly  20  and holding the key button  30  in place with the keypad assembly  20 . The supporting portion  34  is advantageously disc-shaped and formed on a housing of the portable electronic device  10 . The supporting portion  34  has a first through hole  344  defined therethrough. 
   The switching portion  35  includes a main body  352  and three switching elastic sheets  354 . The three switching elastic sheets  354  are formed on a same side of the main body  352  and spaced evenly with one another. The main body  352  is a circular-shaped sheet with a second through hole  3524  defined therethrough. The diametrical size of the second through hole  3524  is bigger than that of the first through hole  344  of the supporting portion  34 . 
   Each of the three switching elastic sheets  354  includes a curve portion  3542  and a straight portion  3544 . The curve portion  3542  is bent with a semi-circular shape and extends from an exterior side of the main body  352 . The curve portion  3542  is configured to be pressed towards the main body  352  with its original semi-circular shape deformed. The straight portion  3544  extends from the curve portion  3542  through the second through hole  3524  of the main body  352 . 
   The pad portion  36  includes a base body  362  and a protruding portion  364 . The protruding portion  364  is formed on the base body  362 . The base body  362  has an accommodating groove  3624  defined therein and three through apertures  3626  defined therethrough. The accommodating groove  3624  is defined corresponding to the main body  352  of the switching portion  35  and configured for accommodating the main body  352  therein. The three through apertures  3626  are defined corresponding to the respective curve portion  3542  and configured for facilitating the three switching elastic sheets  354  engaging through the base body  362  with the three curve portions  3542  respectively engaging through the three through apertures  3626 . 
   The protruding portion  364  is generally cylindrical and has substantially the same size and shape as that of the first through hole  344  of the supporting portion  34 . The protruding portion  364  has three receiving grooves  3628  defined through a surrounding wall thereof corresponding to the three straight portion  3544 s, respectively. The three receiving grooves  3628  respectively communicate with the three through apertures  3626  of the pad portion  36  and configured for receiving the corresponding straight portion  3544  therein as the three switching elastic sheets  354  engaging through the base body  362 . 
   The circuit board portion  38  includes a welding pad  3820 , a first contacting point  3821 , a contacting sheet  384 , and three second contacting points  3822 . The welding pad  3820  is advantageously annular-like and disposed on and electronically connects with the circuit board portion  38 . The contacting sheet  384  is attached to the circuit board portion  38  via soldering with the welding pad  3820 . The contacting sheet  384  thus indirectly electronically connects with the circuit board portion  38  via connecting with the welding pad  3820 . 
   The first contacting point  3821  is disposed on and electronically connects with the circuit board portion  38 . Furthermore, the first contacting point  3821  is located within a space enclosed by the contacting sheet  384  and the circuit board portion  38 . The three second contacting points  3822  are disposed on and electronically connect with the circuit board portion  38  corresponding to the three through apertures  3626  of the pad portion  36 . Advantageously, the three second contacting points  3822  are evenly arranged around the contacting sheet  384  and the first contacting point  3821 . 
   Referring to  FIG. 3 , during assembly, the switching portion  35  is mounted into the pad portion  36 . As such, the main body  352  of switching portion  35  is inserted and accommodated into the accommodating groove  3624  of the base body  362  of the pad portion  36 . The straight portion  3544  of each switching elastic sheet  354  is received in the corresponding receiving groove  3628 . The curve portion  3542  of each switching elastic sheet  354  is inserted and engages through the corresponding through aperture  3626 . 
   After that, the pad portion  36  combined with the switching portion  35  is inserted through the first through hole  344  of the supporting portion  34  and then attached with the key portion  32 . During this stage, the protruding portion  364  of the pad portion  36  engages through the first through hole  344  to attach (e.g. adhere) with the key portion  32 . In this case, the supporting portion  34  is located between the key portion  32  and the main body  352  of the switching portion  35 . The key portion  32  has a lower wall facing the supporting portion  34  to resist against the curve portions  3542  received in the receiving grooves  3628 . The curve portions  3542  thus are retained in the receiving grooves  3628 , respectively. 
   As assembled, the circuit board portion  38  is located below the pad portion  36 . Thus, the pad portion  36  is located between the supporting portion  34  and the circuit board portion  38 . The curve portions  3542  of the switching elastic sheets  354  are located between the pad portion  36  and the circuit board portion  38 . As shown in  FIG. 3 , the curve portions  3542  each contact with an exterior surface of the circuit board portion  38  in its original state without being biased. The curve portions  3542  can instead be biased between the exterior surface of the circuit board and the pad portion  36 . The curve portions  3542  can also be spaced with least distance from the exterior surface of the circuit board portion  38  with a certain space without any contact. 
   In use, as the key portion  32  is pressed towards the circuit board portion  38 , the switching portion  35  moves along with the pad portion  36  and the key portion  32 . The curve portion  3542  of each switching elastic sheet  354  is biased between the circuit board portion  38  and the pad portion  36 . During biasing of the curve portion  3542 , the curve portion  3542  extends in a longitudinal direction along the exterior surface of the curve portion  3542 . 
   As the curve portion  3542  extends and reaches the corresponding second contacting point  3822 , the contacting sheet  384  electronically connects with the second contacting point  3822  via the switching elastic sheet  354 . In this case, the information corresponding to the pressed key portion  32  is inputted into the portable electronic device  10  and advantageously shown in an user interface (not labeled), such as a display window of the portable electronic device  10 . The displayed information is temporary and can disappear from the user interface simply by releasing the key portion  32  of the key button  30 . 
   To make the displayed information valid in the user interface, the key portion  32  needs to be further pressed. During further pressing, the curve portions  3542  extend longitudinally and maintain the electronic connection of the contacting sheet  384  and the second contacting points  3822 . As such, the protruding portion  364  of the pad portion  36  further moves towards the contacting sheet  384 . 
   As the protruding portion  364  reaches the contacting sheet  384  to an extent that the contacting sheet  384  is deformed by the protruding portion  364  to contact the first contacting point  3821 , the first contacting point  3821  electronically connects with the contacting sheet  384 . Thus, the first contacting point  3821 , the contacting sheet  384 , and the second contacting point are electronically connected in the order written. Even if the key portion  32  of the key button  30  is released, the displayed information is maintained valid on the user interface. 
   Alternatively, referring to  FIGS. 4 and 5 , the key button  60  of the second embodiment includes a key portion  62 , a supporting portion  66 , a switching portion  64 , a pad portion  67 , and a circuit board portion  68 . The key portion  62 , the supporting portion  66 , and the circuit board portion  68  are substantially the same as those of the first embodiment of the key button  30 . The supporting portion  66  includes a first through hole  664  defined therethrough. The circuit board portion  68  includes a welding pad  6820 , a first contacting point  6821 , a contacting sheet  684 , and three second contacting points  6822 . Main differences between the first embodiment and second embodiment are reflected on the switching portion  64  or  35  and the pad portion  67  or  36 . 
   The switching portion  64  includes a main body  642  and three switching elastic sheets  644 . The main body  642  is a circular-shaped sheet. The three switching elastic sheets  644  are formed on a same side of the main body  642  and spaced evenly with one another. Each of the three switching elastic sheets  644  is J-shaped. 
   The pad portion  67  has a roughly same structure as that of the pad portion  36  of first embodiment. The pad portion  67  includes a base body  672  and a protruding portion  674 . The base body  672  has three through apertures  6724  defined therethrough corresponding to the three switching elastic sheets  644 . The three through apertures  6724  are configured for facilitating the three switching elastic sheets  644  partially engaging through the three through apertures  6724 . 
   The protruding portion  674  has three receiving grooves  6726  defined therethrough corresponding to the three switching elastic sheets  644 . The three receiving grooves  6726  are configured for receiving the corresponding switching elastic sheet  644  therein as the three switching elastic sheets  644  engaging through the base body  672 . The diametrical size of the main body  642  is shorter than that of the protruding portion  674  of the pad portion  67 . 
   Assembling process and using procedure of the key button  60  are substantially the same as that of the key button  30  of the first embodiment. 
   In other alternative embodiments, the main body of the switching portion can be omitted and the switching elastic sheets of the switching portion then are attached with the protruding portion of the pad portion. The switching portion can instead have at least one switching elastic sheet formed on the main body. Correspondingly, the protrusion portion of the pad portion can instead has at least one receiving groove defined therein. The pad portion can instead has at least one through aperture defined therethrough. The circuit board portion can instead has at least one second contacting point disposed thereon. 
   One main advantage of the present embodiments embodies that two steps of pressing the key button can significantly reduce risks of operating mistake, especially for certain people with bad eye-sight. Users may feel convenient to ascertain whether their input information at the first is what they want or not. If not, they can easily cancel the original input information by simply releasing the pressed key button. 
   It is to be understood, however, that even through numerous characteristics and advantages of the present invention 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.