Patent Publication Number: US-2007123320-A1

Title: Key input device for portable terminal

Description:
CLAIM OF PRIORITY  
      This application claims priority under 35 U.S.C. § 119 to an application entitled “Key Input Device for Portable Terminal,” filed in the Korean Intellectual Property Office on Nov. 30, 2005 and assigned Serial No. 2005-116002, the entire contents of which are hereby incorporated by reference.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention generally relates to a key input device for a portable terminal and in particular, to a key input device having wheel keys capable of rotating in multiple directions to perform various switch functions.  
      2. Description of the Related Art  
      Generally, a portable communication apparatus enables a user to perform a wireless communication with another user. Examples of such portable communication apparatus include Hand Held Phones (HHPs), CT-2 cellular phones, digital phones, Personal Communication Service (PCS) phones, and Personal Digital Assistants (PDAs). The conventional portable devices may be classified into different types, for example, bar-type wireless terminals, flip-type wireless terminals, and folder-type wireless terminals. The bar-type wireless terminal has a single housing. The flip-type wireless terminal has a flip or a cover which is pivotally mounted to a bar-shaped housing via a hinge unit. The folder-type wireless terminal has a folder coupled to a single bar-shaped housing using a hinge unit to allow the folder to be rotated from the housing. These aforementioned conventional portable terminals further include antenna devices, data input/output devices, and data transmission/reception devices.  
      The conventional portable terminals offer multiple functions to meet consumers&#39; demands and becoming smaller. Today, users can perform voice communication, listen to the radio, connect to the Internet to download MP3 music files, and exchange text messages by manipulating key buttons.  
      A keypad used for data input typically includes a plurality of keys such as a send key (SND), a cancel key, a clear key (CLR), numeric keys, character keys, an end key (END), functional keys, and a power key (PWR).  
      The key array generally includes 15-20 keys disposed on a top surface of a housing of a portable terminal. The keys are exposed on the top surface of the portable terminal so that a user can activate them with his/her finger to input desired data.  
      Referring to  FIGS. 1 and 2 , a conventional folder-type portable terminal includes a main body  10  and a folder  20 . In the main body  10 , keys  12 , a four-direction control key  11 , and a microphone  13  are mounted. The folder  20  provides a Liquid Crystal Display (LCD) unit  21  and a speaker  22 . A hinge device  30  is provided between the main body  10  and the folder  20  to rotate upwardly from the main body  10 . An antenna  40  is provided on the main body  10 . The keys  12  are in the form of a key matrix including the twelve 3×4 keys  12  and the four-direction control key  11 .  
      In the main body  10 , a plurality of through holes  14  are formed for pass-through connection between the keys  12  and the four-direction control key  11 . A partition  15  is formed between each pair of through holes  14  to form the 3×4 key matrix. A plurality of dome switches  60  is provided on a Printed Circuit Board (PCB)  50  including circuits in the main body  10 . A signal is generated through a contact between a contact point  51  of the PCB  50  and a contact point  61  of the dome switch  60 .  
      As illustrated in  FIG. 2 , the dome switch  60  is provided on the PCB  50  to output a contact signal according to key activation by the user. The keys  12  and the four-direction control key  11  including up/down/left/right direction keys for various functions are provided on the dome switches  60 . Since the main body of the conventional portable terminal includes twelve keys and a four-direction control key, the exterior design of the portable terminal is restricted due to multiple keys on the portable terminal.  
      Moreover, in the case of the conventional portable terminal, a current graphic user interface is designed to be controlled by a keypad having a plurality of keys, and the conventional graphic user interface uses icon-based information rather than text-based information. To select such icon-based information, an interface between the portable terminal and the user must be made using the four-direction control key.  
      In the conventional portable terminal, a user interface for interfacing with the user evolves into a graphic user interface, but only separate keys can control the graphic user interface. As a result, the lack of user&#39;s intuition occurs due to key pressing, and the user must press the four-direction control key to achieve the movement of an iconized menu screen in different directions, causing inconvenience of manipulation. Furthermore, the plurality of keys on the portable terminal makes miniaturization of the portable terminal difficult, and miniaturization of the keys interferes with the usage by a user.  
     SUMMARY OF THE INVENTION  
      It is, therefore, an object of the present invention to provide an improved key input device for a portable terminal including wheel keys capable of rotating in multiple directions and performing multiple switch functions.  
      One aspect of the present invention to provide a key input device for a portable terminal including wheel keys capable of rotating in multiple directions and performing multiple switch functions, in which an iconized menu screen can be moved rapidly.  
      Another aspect of the present invention to provide a key input device for a portable terminal including wheel keys capable of rotating in multiple directions and performing multiple switch functions, in which there is no need to mount a four-direction control key, thereby reducing a key installing space in the portable terminal. As a result, a further miniaturization of the portable terminal can be realized.  
      Yet another aspect of the present invention to provide a key input device for a portable terminal including wheel keys capable of rotating in multiple directions and performing multiple switch functions, in which a movement in various directions can be made using keys, thereby reducing errors during key operation.  
      In one embodiment, there is provided a key input device for a portable terminal including a plurality of keys. The key input device includes at least one wheel keys provided in a main body and rotating in multiple directions, at least one rotating units allowing the wheel keys to rotate in respective directions, and at least one switching units provided under the wheel keys to sense rotation directions of the wheel keys and sense a pressure generated by press of the rotated wheel keys.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The above features and advantages of exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:  
       FIG. 1  is a perspective view showing a folder of a conventional folder-type portable terminal is opened;  
       FIG. 2  is a cross-sectional view taken along a line A-A′ of  FIG. 1 ;  
       FIG. 3  is a perspective view of a key input device of a portable terminal according to an embodiment of the present invention;  
       FIG. 4  is an enlarged exploded perspective view of a portion A of  FIG. 3 ;  
       FIG. 5  is a perspective view showing a key input device in a portable terminal according to an embodiment of the present invention;  
       FIG. 6  is an enlarged partially-cut perspective view showing a key input device according to an embodiment of the present invention;  
       FIG. 7  is an enlarged plane view showing a key input device according to an embodiment of the present invention;  
       FIG. 8  is an enlarged side cross-sectional view showing a key input device according to an embodiment of the present invention; and  
       FIG. 9  is a plane view showing a key input device of a portable terminal during operation in accordance with an embodiment of the present invention.  
    
    
     DETAILED DESCRIPTION  
      Hereinafter, descriptions of well-known functions and constructions are omitted for clarity and simplicity.  
      Referring to  FIGS. 3 and 4 , a key input device for a portable terminal includes at least one wheel keys  100 , at least one rotating units  110 , and at least one switching units  120 . The wheel keys  100  are included in a main body  10  of the portable terminal to rotate in up/down/left/right directions. The rotating unit  110  is located adjacent to the wheel key  100  to allow the wheel key  100  to rotate in up/down/left/right directions. The switching unit  120  is located under the wheel key  100  to sense the rotation direction of the wheel key  100  and sense a pressure generated by user&#39;s press when being rotated.  
      Referring to  FIGS. 5 and 9 , the wheel keys  100  are mounted in positions corresponding to keys  12  numbered 2, 4, 6, and 8 in a 3×4 key matrix of a keypad. The wheel keys  100  in the positions of the 2 and 8 keys can rotate in up/down directions, and the wheel keys  100  in the positions of the 4 and 6 keys can rotate in left/right directions.  
      Referring to  FIGS. 4 and 6 , the rotating unit  110  includes a pair of rotating rollers  111  and a pair of rotating supports  112 . The rotating roller  111  protrudes from the center of the wheel key  100  to be combined with the rotating support  112  such that the rotating roller  111  can rotate with respect to its rotating axis A 1 . The rotating support  112  is located adjacent to the rotating roller  111  to be combined with a guide hole of the rotating roller  111  such that the rotating support  112  can rotate with respect to the rotating axis A 1  of the rotating roller  111  and support the rotating roller  111 .  
      Referring to  FIGS. 6 and 7 , a click unit  130  is located adjacent to the rotating support  112  to provide the sense of rotational clicking during rotation of the wheel key  100  by contacting a sawtooth unit  101  formed in one side of the wheel key  100 .  
      Referring to  FIG. 8 , the rotating support  112  includes a guide hole  112   a  for guiding a movement of the rotating roller  111  of the wheel key  100  to a direction in which the wheel key  100  is pressed.  
      Referring to  FIGS. 6 and 8 , the switching unit  120  includes a first sensor  121  and a second sensor  122 . The first sensor  121  electrically contacts the circumference of the wheel key  100  to sense the rotation direction of the wheel key. The second sensor  122  is located under the first sensor  121  to sense the pressure generated by user&#39;s activation of the wheel key  100 .  
      Referring to  FIG. 3 , at least one protruding holes  10   a  are formed on the surface of the main body  10  to allow the wheel key  100  to protrude from the surface of the main body  10 .  
      Now, the operation of the key input device of the portable terminal according to an embodiment of the present invention will be described in detail with reference to  FIGS. 3 through 9 .  
      As illustrated in  FIGS. 3 and 4 , the key input device of the portable terminal includes at least one wheel keys  100 , at least one rotating units  110 , and at least one switch units  120 .  
      As illustrated in  FIG. 9 , the key input device includes a keypad having a 3×4 key matrix, and the wheel keys  100  are mounted in positions of the 2, 4, 6, and 8 keys  12  in the 3×4 key matrix. The wheel keys  100  in the positions of the 2 and 8 keys  12  can rotate in up/down directions, and the wheel keys  100  in the positions of the 4 and 6 keys  12  can rotate in left/right directions. Note that the wheel keys  100  may also be mounted in positions of other keys  12 .  
      Since the rotating roller  111  protrudes from the center of the wheel key  100 , and the rotating support  112  is located adjacent to the rotating roller  111  to be combined with a guide hole of the rotating roller  111  such that the rotating support  112  can rotate with respect to the rotating axis A 1  of the rotating roller  111  and support the rotating roller  111 , as illustrated in  FIG. 6 . The rotating roller  111  can be rotatably combined by the rotating support  112 . The rotating support  112  includes the guide hole  112   a  into which the rotating roller  111  is inserted.  
      Referring to  FIGS. 6 through 8 , the click unit  130  is located adjacent to the rotating support  112  to be combined with the sawtooth unit  101  formed in one side of the wheel key  100 . Thus, the rotating roller  111  of the wheel key  100  is inserted into the guide hole  112   a  of the rotating support  112 , and the sawtooth unit  101  of the wheel key  100  is combined with the click unit  130 .  
      The switching unit  120  is located under the wheel key  100  as illustrated in  FIG. 9 .  
      In this state, to move to an icon (not shown) displayed on a Liquid Crystal Display (LCD) unit  21  of the portable terminal in up/down directions, the user rotates the wheel key  100  in the position of the 2 or 8 key  12  in up/down directions.  
      Thus, as illustrated in  FIG. 6 , the wheel key  100  rotates together with the rotation of sawtooth unit  101  of the wheel key  100 , in which the sawtooth unit  101  is inserted into and drawn out from the click unit  130  to provide the sense of rotational click of the wheel key  100 .  
      Since the first sensor  121  that electrically contacts the circumference of the wheel key  100  is included in the switching unit  120 , the first sensor  121  senses up/down rotation directions of the wheel key  100  upon rotation of the wheel key  100 .  
      Upon reaching a desired icon (not shown) in the display  21 , the user presses the wheel key  100 . At this time, the second sensor  122  under the first sensor  121  senses a pressure generated by user&#39;s press of the wheel key  100 . The second sensor  122  senses the pressure and clicks the desired icon through a switch function.  
      When the wheel key  100  moves in the pressed direction, the rotating roller  111  of the wheel key  100  also moves along the guide hole formed in the rotating support  112 .  
      As illustrated in  FIG. 9 , to move to an icon (not shown) displayed on the LCD unit  21  of the portable terminal in left/right directions, the user rotates the wheel key  100  in the position of the 4 or 6 key  12  in left/right directions.  
      As illustrated in  FIG. 9 , the wheel key  100  rotates together with the rotation of sawtooth unit  101  of the wheel key  100 , and the sawtooth unit  101  is inserted into and drawn out from the click unit  130  to provide the sense of rotational clicking of the wheel key  100 .  
      Since the first sensor  121  that electrically contacts the circumference of the wheel key  100  is included in the switching unit  120 , the first sensor  121  senses left/right rotation directions of the wheel key  100  upon rotation of the wheel key  100 .  
      Upon reaching the desired icon (not shown), the user presses the wheel key  100 . At this time, the second sensor  122  under the first sensor  121  senses a pressure generated by user&#39;s press of the wheel key  100 . The second sensor  122  senses the pressure and clicks the desired icon through a switch function.  
      As described above, according to the present invention, by using a key input device for a portable terminal, which includes wheel keys capable of rotating in up/down/left/right directions and performing various switch functions, a key input function of the portable terminal can be improved and an iconized menu screen can be moved rapidly. Moreover, there is no need to mount a conventional four-direction control key, thereby reducing a key installing space, and thus contributing to a miniaturization of the portable terminal.  
      While the present invention has been shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. For example, the present invention is applicable to all portable terminals.