Abstract:
A hinge assembly includes a central shaft ( 20 ), including an outer screw thread ( 221 ); a turning element ( 30 ), including a central hole ( 322 ) and a holding pin ( 314 ), an inner screw thread ( 323 ) formed at an inner surface of the central hole; a elastic means ( 40 ); a blocking element ( 50 ), defining a first through hole ( 51 ) and a second through hole ( 52 ); and a button ( 71 ), including a supporting pin ( 72 ). The central shaft extends through the central hole of the turning element, the first elastic element, and the first through hole of the blocking element in that order, the outer screw thread engages with the inner screw thread, and the holding pin of the turning element is received in the second through hole of the blocking element. The present invention enables a foldable electronic device to be opened simply by pressing the button.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is related to U.S. patent application Ser. No. 10/920,760, entitled “HINGE ASSEMBLY FOR FOLDABLE ELECTRONIC DEVICE” and filed on Aug. 17, 2004. The disclosure of the above identified applications is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to hinge assemblies, and particularly to a hinge assembly for hinging a cover and a body of a foldable electronic device together.  
         [0004]     2. Prior Art  
         [0005]     Portable electronic devices, such as cellular phones and PDAs (personal digital assistants), are becoming ever more popular with the development of wireless communication technology and data processing technology.  
         [0006]     For example, a foldable cellular phone commonly has a cover and a body joined by some type of hinge that allows the cover to fold upon the body. Some foldable phones have most of the electronics provided in the body. The cover normally contains fewer electronic components than the body. Other foldable phones have essentially all the electronics provided in the body, with the cover serving only to cover and protect the keypad and the display of the phone.  
         [0007]     U.S. Pat. No. 5,628,089, issued to Wilcox et al. and entitled “Radiotelephone Having a Self Contained Hinge,” discloses a hinge for use in a miniaturized radiotelephone. This hinge is represented in  FIG. 5 . The hinge  80  comprises a spring  82 , a cam  83  and a follower  84  assembled into a cylindrically hollow can  81  via an open end thereof, and held in assemblage by a cap  85  coupled to the can  81  over the open end. The hinge  80  can be attached in a cavity of a cover and a cavity of a body of the radiotelephone.  
         [0008]     This kind of self contained hinge is desired by many foldable cellular phone manufacturers because it can be purchased as a separate unit, thereby eliminating the steps associated with assembling such hinge during manufacturing. However, a foldable cellular phone with such hinge can be opened automatically only after the cover has first been turned about the body by a user. It is not easy for the user to open the cellular phone with only one hand, for example when the user is driving a car or is otherwise occupied. Furthermore, the cover is prone to open quickly and jar against the body. After repeated use, the body and the cover are liable become worn out and not operate properly.  
         [0009]     Thus, a need exists for a convenient and highly reliable hinge assembly which is suitable for use in a foldable electronic device, and which overcomes the above-described problems.  
       SUMMARY OF THE INVENTION  
       [0010]     An object of the present invention is to provide a hinge assembly for a foldable cellular phone, the hinge assembly being highly reliable and operable with a simple key or button.  
         [0011]     To accomplish the above-mentioned object, the present invention provides a hinge assembly for joining a body and a cover of a foldable electronic device. The hinge assembly includes a central shaft, including an outer screw thread; a turning element, including a central hole and a holding pin, an inner screw thread formed at an inner surface of the turning element in the central hole; a first elastic means; a blocking element, defining a first through hole and a second through hole; and a button, including a supporting pin. The central shaft is extends through the central hole of the turning element, a first elastic element, and the first through hole of the blocking element in that order, the outer screw thread of the central shaft engages with the inner screw thread of the turning element, a first end of the first elastic means is supported by the blocking element, a second end of the first elastic means is supported by the turning element, and the holding pin of the turning element is received in the second through hole of the blocking element, and corresponds to the supporting pin of the button.  
         [0012]     The hinge assembly of the invention enables a foldable cellular phone to be opened simply by pressing a single button. Users can operate the phone conveniently without having to use both hands.  
         [0013]     Other objects, advantages and novel features of the invention will be drawn from the following detailed description with reference to the attached drawings, in which: 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1  is an isometric view of a hinge assembly in accordance with the present invention;  
         [0015]      FIG. 2  is an exploded view of the hinge assembly of  FIG. 1 ;  
         [0016]      FIG. 3  is similar to  FIG. 2 , but viewed from another aspect;  
         [0017]      FIG. 4  is a cross-sectional view taken along line IV-IV of  FIG. 1 ; and  
         [0018]      FIG. 5  is an exploded, isometric view of a hinge assembly of the prior art. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0019]     An exemplary embodiment of a hinge assembly in accordance with the present invention is shown in FIGS.  1  to  3 . The hinge assembly  10  of the present invention is applied to a foldable mobile phone (not shown) with a cover (not shown) and a body (not shown). The hinge assembly  10  includes a central shaft  20 , a turning element  30 , a helical spring  40 , a blocking element  50 , a C-shaped fixing clip  60 , and a button module  70 . The turning element  30 , the spring  40 , the blocking element  50 , the fixing clip  60  and the button module  70  are assembled with the central shaft  20  in that order, and the central shaft  20  connects with the turning element  30  by outer and inner screw threads  221 ,  323  thereof respectively.  
         [0020]     The central shaft  20  of the hinge assembly  10  includes a main body  21 , and a connecting head  22  integrally joined with an end of the main body  21 . A diameter of the main body  21  is smaller than a diameter of the connecting head  22 . The main body  21  includes a main portion  211  and an end portion  212 . The main portion  211  is cylindrical, and adjoins the connecting head  21 . A peripheral surface of the end portion  212  includes two opposite flat surfaces (not labeled) and two opposite arcuate surfaces (not labeled). An annular fixing groove  213  is defined in the end portion  212 . The outer screw thread  221  is formed at a peripheral surface of the connecting head  22 .  
         [0021]     The turning element  30  is received in a corresponding receiving groove (not shown) of the cover of the mobile phone, and can move along an axis A. The turning element  30  includes a front portion  31  and a rear portion  32 . The front portion  31  is cylindrical, and includes a second central hole  311 , two receiving sockets  312 , two helical springs  313 , and two holding pins  314 . The receiving sockets  312  are symmetrically defined at opposite sides of the second central hole  311 . Two fixing protuberances  318  (best seen in  FIG. 4 ) are formed on the rear portion  32  at bottoms of the receiving sockets  312  respectively. The springs  313  are respectively received in the receiving sockets  312 , with rear ends of the springs  313  receiving the fixing protuberances  318  and being supported on the rear portion  32  at the bottoms of the receiving sockets  312 . Each holding pin  314  includes a main portion  3142 , an annular flange  315 , and a connecting portion  3141 . An outer diameter of the connecting portion  3141  is less than an inner diameter of each spring  313 . The flange  315  interconnects the connecting portion  3141  and the main portion  3142 . An outer diameter of the flange  315  is larger than the inner diameter of each spring  313 . The holding pins  314  are respectively received in the receiving sockets  312 . The connecting portions  3141  of the holding pins  314  are received in the springs  313 , with the flanges  315  of the holding pins  314  supporting front ends of the springs  313 .  
         [0022]     The rear portion  32  of the turning element  30  is cylindrical. An outer diameter of the rear portion  32  is larger than an outer diameter of the front portion  31 , so that a step  321  is formed where the rear portion  32  adjoins the front portion  31 . The rear portion  32  defines a first central hole  322 . The first central hole  322  is coaxial and in communication with the second central hole  311 . The inner screw thread  323  is formed on an inner surface of the rear portion  32  in the first central hole  322 . Two opposite protuberances  324  are formed on an outer surface of the rear portion  32 , for preventing the turning element  30  from rotating in the receiving groove of the mobile phone.  
         [0023]     The spring  40  receives the front portion  31  of the turning element  30 , and a rear end of the spring  40  is supported by the step  321  of the turning element  30 .  
         [0024]     The blocking element  50  is fixed in the body of the mobile phone, and supports a front end of the spring  40 . The blocking element  50  defines a central first through hole  51  and two opposite second through holes  52 . An inner surface of the blocking element  50  in the first through hole  51  has two opposite flat surfaces (not labeled) and two opposite curved surfaces (not labeled). The first through hole  51  corresponds to the central holes  311 ,  322  of the turning element  30 . The first through hole  51  receives the end portion  212  of the central shaft  20 , such that the central shaft  20  is prevented from rotating in the first through hole  51 . The second through holes  52  correspond to the receiving sockets  312 , and receive the main portions  3142  of the holding pins  314 .  
         [0025]     The button module  70  includes a button  71  and a helical spring  73 . The button  71  includes a blocking board  74 , a head  76 , and two supporting pins  72 . The head  76  extends from a front surface of the blocking board  74 , and the supporting pins  72  extend from a rear surface of the blocking board  74 . A first central through hole  77  is defined in a center of the head  76 . A second central through hole  78  is defined in a center of the blocking board  74 . The first central through hole  77  is coaxial and in communication with the second central through hole  78 . A diameter of the first central through hole  77  is smaller than a diameter of the second central through hole  78 , so that an inner step  711  is formed where the first central through hole  77  adjoins the second central through hole  78 . The central through holes  77 ,  78  are coaxial with the first through hole  51  of the blocking element  50 . The supporting pins  72  can be inserted into the second through holes  52  of the blocking element  50 . The spring  73  is received in the second central through hole  78 . A front end of the spring  73  is supported by the step  711 . The fixing clip  60  is fixed in the fixing groove  213  of the central shaft  20 , and supports a rear end of the spring  73 . The button  71  is located in a hole in a sidewall of the mobile phone, with the head  76  of the button  71  protruding beyond an outer surface of the mobile phone.  
         [0026]     Referring to  FIG. 4 , in assembly of the hinge assembly  10 , the central shaft  20  is inserted through the first central hole  322  and the second central hole  311  of the turning element  30 , the spring  40 , and the first through hole  51  of the blocking element  50 . The end portion  212  of the central shaft  20  is held in the first through hole  51  of the blocking element  50 . The fixing clip  60  is fixed in the fixing groove  213  of the central shaft  20 . The spring  73  and the button  71  are attached around the central shaft  20  in that order. The first central through hole  77  of the button  71  receives the end portion  212  of the central shaft  20 . The outer screw thread  221  of the central shaft  20  engages with the inner screw thread  323  of the turning element  30 . The main portions  3142  of the holding pins  314  and the supporting pins  72  are partly received in the second through holes  52  of the blocking element  50 . At this time, the spring  40  is compressed and supports the turning element  30 . The turning element  30  can rotate and move along the axis A by engagement of the outer screw thread  221  of the central shaft  20  with the inner screw thread  323  of the turning element  30 . However, because the main portions  3142  of the holding pins  314  are engaged in the second through holes  52  of the blocking element  50 , the turning element  30  cannot rotate.  
         [0027]     To open the cover of the mobile phone, the head  76  of the button  71  is pressed. The supporting pins  72  of the button  71  push the holding pins  314  and compress the springs  313 . The holding pins  314  move deeper into the receiving sockets  312  until the main portions  3142  of the holding pins  314  exit the second through holes  52  of the blocking element  50 . At this time, rotation of the turning element  30  is not limited by the blocking element  50 . The spring  40  decompresses, and drives the turning element  30  to move rearward along the axis A. Simultaneously, because of the engagement of the screw threads  221 ,  323 , the turning element  30  rotates about the central shaft  20 . The cover of the mobile phone is thus driven to an open position.  
         [0028]     To close the cover of the mobile phone, the cover is manually rotated. The turning element  30  rotates with the cover and moves forward along the axis A, and the spring  40  is compressed. The cover is thus rotated until the holding pins  314  reach the second through holes  52  of the blocking element  50 . At this point, the springs  313  decompress and drive the holding pins  314  into the second through holes  52  until the holding pins  314  abut the supporting pins  72  of the button  71 . The cover of the mobile phone is thus returned to and retained in the closed position.  
         [0029]     In alternative embodiments, the springs  313 ,  73  can be replaced by other elastic means such as sponge rubber pieces. The springs  313  can be omitted. That is, the holding pins  314  directly abut the fixing protuberances  318 . Alternatively, the holding pins  314  can be integrally formed on the front portion  31  of the turning element  30  at bottoms of the receiving sockets  312  respectively. In any of such alternative embodiments, when the head  76  of the button  71  is pressed, the supporting pins  72  of the button  71  push the holding pins  314  rearward along the axis A until the holding pins  314  exit the second through holes  52  of the blocking element  50 . At this time, rotation of the turning element  30  is not limited by the blocking element  50 . The spring  40  decompresses, and drives the turning element  30  to move rearward along the axis A. Simultaneously, because of the engagement of the screw threads  221 ,  323 , the turning element  30  rotates about the central shaft  20 . The cover of the mobile phone is thus driven to an open position. In further alternative embodiments, the turning element  30  can be received in the body of the mobile phone, and can move along the axis A. The blocking element can accordingly be fixed in the cover of the mobile phone.  
         [0030]     It is to be understood that even though 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.