Patent Publication Number: US-2011058324-A1

Title: I/o shield structure and motherboard module thereof

Description:
BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The invention relates to an input/output (I/O) shield structure and, more particularly, to an I/O shield structure which only contacts a casing and is unfixed at the casing to avoid the assembly interference. 
     2. Related Art 
     A motherboard of a common computer system is fixed on a casing, and the casing has an assembly window corresponding to the I/O connecting portion of the motherboard to expose the I/O connecting portion. Thus, a user may insert various external devices such as a mouse, a keyboard and a USB device. Since the I/O connecting portion is fine, and the demand for the size is relatively high, the assembly window of the casing is rectangle, and an I/O shield made of a metal thin part is disposed at the assembly window additionally. The I/O shield has openings with different shapes cooperating with each connector of the I/O connecting portion to beautify the whole casing. 
     In assembling, the I/O shield is first fastened to the assembly window of the casing, and then the motherboard is disposed with the I/O connecting portion aiming the I/O shield to expose each connector. Afterward, the motherboard is locked to the casing via the screws. However, due to the tolerance in the manufacturing, the casing and I/O shield both have some size difference, and then the I/O connecting portion cannot aim the I/O shield accurately. Thus, some connectors are covered by the I/O shield and cannot be used by the user successfully. 
     In addition, due to the tolerance, great strength needs to be used to fasten the I/O shield. In addition, the I/O shield is usually a thin metal part, it easily cuts the hand of an assembler or is pushed out of the assembly window of the casing in assembling. 
     SUMMARY OF THE INVENTION 
     The invention provides an I/O shield structure including a cover and shield. The cover is disposed at and covers an I/O connecting portion of the motherboard. The shield includes an opening corresponding to the I/O connecting portion. Overall electromagnetic interference (EMI) suppression and electrostatic discharge (ESD) prevention may be achieved by fixing the shield at the cover. 
     The invention also provides a motherboard module with an I/O shield structure including a motherboard, a cover and a shield. The motherboard has an I/O connecting portion, and the cover is disposed at and covers the I/O connecting portion of the motherboard. The shield has an opening corresponding to the I/O connecting portion, a first surface and a second surface opposite to the first surface. At least a first conductor is disposed at the periphery of the second surface to be fixed at the cover via the shield. The motherboard is disposed with the I/O connecting portion facing the assembly window of the casing. The shield and the I/O connecting portion electrically communicate to the casing by making the first conductor contact the periphery of the assembly window to improve the effect of suppressing the EMI. Furthermore, since the shield is fixed at the motherboard and only contacts the casing, even tolerance exists between the casing, the shield and the motherboard, the assembly interference does not exist. 
     These and other features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded diagram showing the I/O shield structure and the motherboard module thereof according to an embodiment of the invention; 
         FIG. 2  is an assembly diagram showing the I/O shield structure and the motherboard module thereof according to an embodiment of the invention; 
         FIG. 3  is an assembly diagram showing the I/O shield structure and the motherboard module are assembled to the casing according to an embodiment of the invention; 
         FIG. 4  is a sectional diagram showing that the I/O shield structure and the motherboard module are assembled to the casing according to the embodiment of the invention; and 
         FIG. 5  is a schematic diagram showing the I/O shield structure and the motherboard module thereof according to another embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is an exploded diagram showing the I/O shield structure and the motherboard module thereof according to an embodiment of the invention, and  FIG. 2  is an assembly diagram showing the I/O shield structure and the motherboard module thereof according to an embodiment of the invention. 
     The motherboard module includes a motherboard  10  and an I/O shield structure  20 . The motherboard  10  is substantially a plate, and at least an I/O connecting portion  11  is disposed thereon. The I/O connecting portion  11  is composed of at least a connector. As shown in  FIG. 1 , the I/O connecting portion  11  includes various connectors such as a P/S2 connector for connecting a mouse or a keyboard  111 , a USB connector  112 , a network connector  113  and an audio connector  114 . Since there are many different kinds of the connectors, and the motherboard  10  with a different specification has different connectors, the connectors shown in  FIG. 1  are taken as example. 
     I/O shield structure  20  includes a shield  21  and the cover  22 . The shield  21  is substantially laminate-shaped and has a first surface  212  and a second surface  211  opposite to the first surface  212 , and the shield  21  has at least an opening  213  corresponding to a connector of the I/O connecting portion  11  to allow the connector of the I/O connecting portion  11  to be exposed. 
     A second conductor  31  is disposed at the first surface  212  of the shield  21 , and assembly portions  214  extend from the periphery of the second surface  211 . The first conductors  32  are disposed at the assembly portions  214 . In the embodiment, the second conductor  31  and the first conductor  32  are in the form of the conductive foam, and the second conductor  31  also has at least one opening  311  corresponding to the connector of the I/O connecting portion  11  to expose the connectors of the I/O connecting portion  11 . The second conductor  31  also may be realized by a plurality of conductive foam disposed at the first surface  212  of the shield  21 . 
     The cover  22  is a conductive metal cover with an open bottom and an open surface adjacent to the bottom. At least an inserting portion  222  is disposed at the bottom and may be inserted into the corresponding assembly hole  12  to dispose the cover  22  at the I/O connecting portion  11  on the motherboard  10 . After being assembled, the cover  22  covers the I/O connecting portion  11 , and space at one side of the connector is open (as shown in the left of  FIG. 1 ). The mode of fixing the cover  22  to the motherboard  10  may be soldering with the I/O connecting portion  11  by cooperating the inserting portion  222  with the assembly hole  12 . The cover  22  may be fixed in other modes such as tight fit, locking, fastening or holding. 
     The first surface  212  of the shield  21  is connected to the cover  22  to make the connector of the I/O connecting portion  11  exposed from the opening  213  of the shield  21 , and the other part of the I/O connecting portion  11  is covered by the cover  22  and the shield  21  to suppress electromagnetic interference (EMI) overall. The shield  21  may be fixed to the cover via the hook  215  and the fixing hole  221  as shown in  FIG. 1 , and it also may be fixed in other modes such as adhering or locking. 
       FIG. 3  is an assembly diagram showing that the I/O shield structure and the motherboard module are assembled to the casing.  FIG. 4  is a sectional diagram showing the I/O shield structure and the motherboard module are assembled to the casing. 
     When being assembled to the casing  40 , the shield  21  and the I/O connecting portion  11  face the assembly window  41  to allow shield  21  to contact the periphery of the assembly window  41  via the first conductors  32  on the peripheral assembly portions  214 . Then, the motherboard  10  is fixed to the casing  40 , and it is usually fixed via screws, which is not the characteristic of the invention and is the conventional technology. Therefore, the mode of fixing the motherboard is not described herein for a concise purpose. 
     After assembled, the cover  22 , the I/O connecting portion  11 , the shield  21  and the casing  40  electrically communicate to each other via the second conductor  31  and the first conductor  32 . Thus, not only the electromagnetic interference (EMI) is suppressed, and the electrostatic discharge (ESD) is prevented. To achieve the objective, besides the second conductor  31  and the first conductor  32 , the cover  22  and the shield  21  are also made of conductive material which usually is metal. 
     Since the shield  21  only contacts the casing and is unfixed at the casing  40 , the assembly tolerance between the casing  40 , the shield  21  and the motherboard  10  may be eliminated via the tolerance provided by the contacting and unfixing assembly mode. Thus, the assembly interference does not exist. In other words, as shown in  FIG. 4 , the interference in the left and right direction is absorbed via the elasticity of the second conductor  31  and the first conductor  32 , and the interference in the up and down direction is absorbed via the first conductor  32  which only contacts the casing  40  and is unfixed to the casing  40 . Thus, the assembly interference is avoided. 
     If the shield  22  and the cover  21  are not made of conductive material, a conductive structure may be disposed around the I/O connecting portion  11  to connect the ground, and then the same effect of providing tolerance in the assembly mode is achieved. 
       FIG. 5  is a schematic diagram showing the I/O shield structure and the conductor of the motherboard module according to another embodiment of the invention. 
     Besides the conductive foam, the second conductor  31  and the first conductor  32  also may be in the form of common metal elastic sheets. In other words, second metal elastic sheets  34  are disposed on the assembly portion  214  of the shield  21  and protrude toward the second surface  211 . First metal elastic sheets  33  are disposed adjacent to the opening  213  and protrude toward the first surface  212 . Thus, the same effect is achieved. 
     Thus, in the I/O shield structure and the motherboard module thereof provided in the invention, the shield is designed to be fixed on the motherboard via the cover instead of being fixed on the casing as the conventional technology. Therefore, not only the assembly is more convenient, and the assembly interference generated by the tolerance is avoided. Cooperating with the design of the cover, the shield and the conductor, the over EMI suppression and the ESD prevention are achieved. 
     Although the present invention has been described in considerable detail with reference to certain preferred embodiments thereof, the disclosure is not for limiting the scope of the invention. Persons having ordinary skill in the art may make various modifications and changes without departing from the scope and spirit of the invention. Therefore, the scope of the appended claims should not be limited to the description of the preferred embodiments described above.