Abstract:
A rotary mechanism includes a base ( 10 ), a cover ( 30 ), a torsion spring ( 40 ) and a locking module ( 60 ). The cover is rotatably mounted to the base. Two ends of the torsion spring are fixed with the base and the cover respectively. The locking module limits the cover rotation relative to the base. When the cover overcomes the limitation of the locking module, the cover is automatically rotated relative to the base by the torsion spring.

Description:
BACKGROUND 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to rotary cover mechanisms and, particularly, to rotary cover mechanisms for portable electronic devices, such as mobile phones and portable computers. 
         [0003]    2. Description of Related Art 
         [0004]    With the development of wireless communication and information processing technologies, portable mobile terminals, such as mobile phones and personal digital assistants (PDAs), are now in widespread use. 
         [0005]    Typical portable electronic devices such as mobile phones mainly include bar mobile phones, foldable mobile phones, slidable mobile phones, and rotatable mobile phones. Rotatable mobile phones have a newer structure which allows the mobile phone to be compact with a modern, novel design. 
         [0006]    A traditional rotating mechanism for a mobile phone includes a cover having a display and a body having a keypad. When a user holds this type of mobile phone with one hand, the cover is rotated 180 degrees relative to the body to expose the keypad. When the mobile phone is closed, the cover covers the body, and the keypad is hidden. However, when opening or closing the phone, the mobile phone needs a continued external force to rotate the cover relative to the body. This can make one-handed operation very difficult. 
         [0007]    Therefore, there is a room for improvement within the art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    Many aspects of the present rotating mechanism 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 present rotating mechanism. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views, in which: 
           [0009]      FIG. 1  is an exploded, isometric view of an exemplary rotating mechanism; 
           [0010]      FIG. 2  is similar to  FIG. 1 , but viewed from another angle; 
           [0011]      FIG. 3  is an assembled, partially cut-away view of the exemplary rotating mechanism showing a closed state; and; 
           [0012]      FIG. 4  is an open state view of the exemplary rotating mechanism of  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0013]      FIGS. 1 and 2  show an exemplary rotating mechanism  100  including a base  10 , a rotary cover  30 , a torsion spring  40 , a cushion  50  and a locking module  60 . 
         [0014]    The base  10  includes an upper surface  1   02  and an opposite lower surface  104 . A cylindrical sleeve  13  is formed at one end of the upper surface  102 . The sleeve  13  defines a pin hole  132  in an outer circumferential wall thereof. Adjacent to one side of the sleeve  13 , the upper surface  102  defines an arcuate sliding groove  15 . The sliding groove  15  covers  1   80  degrees. Adjacent the other side of the sleeve  13 , the upper surface  102  defines a recess  17 . A protrusion  18  is formed on the lower surface  104  in a position corresponding to the recess  17 . The protrusion  18  includes a bottom wall  172  and four sidewalls  174 . The bottom wall  172  extends a positioning post  176  toward the upper surface  102  in the recess  17 . Two opposite sidewalls  174  respectively define an opening  178  communication with the recess  17 . 
         [0015]    The rotary cover  30  has a first surface  31  and an opposite second surface  32 . One end of the first surface  31  defines a receiving hole  312  for rotatably receiving the sleeve  13 . A cylindrical flange  313  is formed on the second surface  32  in a position corresponding to the receiving hole  312 . Adjacent to the receiving hole  312 , a block  314  is formed on the first surface  31 . The block  314  is configured for slidably engaging the sliding groove  15 . The first surface  31  defines a circular concave depression  316 . Correspondingly, a projection  317  is formed on the second surface  32 . The second surface  32  positions a fixing portion  332  opposite to the projection  317 . The fixing portion  332  is a substantially U-shaped frame, and includes a top board  3320  and two side boards  3321 . The top board  3320  defines a pivot hole  3324 . 
         [0016]    The torsion spring  40  has a coiled portion  41 . An inner diameter of the coiled portion  41  is substantially equal to an outer diameter of the sleeve  13 , thereby allowing the coiled portion  41  to be placed around the sleeve  13 . The coiled portion  41  has a first end portion  43  and a second end portion  45 . The first end portion  43  is bent in a radial direction. The second end portion  45  is bent in an axial direction, and is further perpendicularly bent. The first end portion  43  is used for being locked in the pin hole  132 , and the second end portion  45  is used for being engaged in the pivot hole  3324 . 
         [0017]    A diameter of the cushion  50  is substantially equal to an outer diameter of the sleeve  13 . The cushion  50  is made of plastic or rubber, and positions between the torsion spring  40  and the flange  313  of the rotary cover  30 , for reducing friction therebetween. 
         [0018]    The locking module  60  includes a spring  61  and a locking member  62 . An inner diameter of the spring  61  is larger than that of the positioning post  176  so that the spring  61  may be placed around the positioning post  176 . The locking member  62  has a seat  622 . A top surface of the seat  622  forms a bulge  624 , and a bottom surface of the seat  622  defines a containing groove  6222 . Two sides of the seat  622  respectively form a clasp  6224  configured for engaging in a corresponding opening  178 . 
         [0019]    Referring to  FIG. 3 , when assembling the rotating mechanism  100 , firstly, the spring  61  is placed around the positioning post  176  in the recess  17 . Then, the locking member  62  positions above the spring  61 , and one end of the spring  61  is received in the containing groove  6222 . The clasps  624  are respectively locking in a corresponding opening  178 . After that, the receiving hole  312  of the cover  30  is placed around the sleeve  13  of the base  10 . At the same time, the block  314  of the cover  30  is received in the sliding groove  15 , and the bulge  624  of the locking member  62  is pressed in the containing groove  6222  by the spring  61 . The cushion  50  positions on the flange  313 . The torsion spring  40  is placed around the sleeve  13 , and positions on the cushion  50 . The first end portion  43  is inserted into the pin hole  132 , and the second end portion  45  is inserted into the pivot hole  3324 . At an initial state, the torsion spring  40  has a predetermined torisional force so the cover  30  is biased towards opening. However, the bulge  624  is limited in the containing groove  316  so the cover  30  is held in a closed position relative to the base  10 . 
         [0020]    Referring to  FIG. 4 , to open the rotating mechanism  100 , the rotary cover  30  is manually rotated along the sliding groove  15  so that the bulge  624  overcomes the containing groove  316 . Accordingly, the rotary cover  30  automatically rotates due to the torsion spring  40 . The block  314  slides along the sliding groove  15  until the block  314  reaches the end of the sliding groove  15 . At that time, the rotary cover  30  is automatically opened 180 degrees. 
         [0021]    To close the rotary mechanism  100 , the rotary cover  30  is reversely rotated until the bulge  624  of the locking member  62  is received in the containing groove  316 . When the rotary cover  30  is rotated until the rotary cove  30  is closed relative to the base  10 , the torsion spring  30  accumulates torisonal energy for the next opening process. 
         [0022]    The spring  61  may alternatively have a different configuration, for example, a leaf spring or a resilient cylinder. The positioning post  176  may be omitted, and the spring  61  may be received in the recess  17 . 
         [0023]    It is believed that the present embodiments and their 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 invention or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the invention.