Patent Publication Number: US-2009237893-A1

Title: Fixing structure for fixing a circuit board

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a fixing structure for fixing a circuit board, and more particularly, to a fixing structure with elastic components for clamping a circuit board. 
     2. Description of the Prior Art 
     With the rapid development of information technology, computer systems are playing an important role in modernizing many companies, which now are widely used in practically every industry. Due to the increase in data storage density, the improvement in clock speed, and the decrease in production costs, the manufacturing of portable computers has become a mainstream business in the computer industry. In general, the computer system includes a case for covering and protecting internal components. Sometimes a circuit board, such as a motherboard, is screwed to a boss of the case. However, because the circuit board is not screwed in equilibrium due to mechanical tolerance, the circuit board is not level so as to induce plane stress. It might cause local fracture due to stress concentration, and electronic components on the circuit board are brittle when an impact is applied to the circuit board. 
     SUMMARY OF THE INVENTION 
     It is therefore a primary objective of the invention to provide a fixing structure with elastic components for clamping a circuit board for solving the above-mentioned problem. 
     According to the claimed invention, a fixing structure includes a first case whereon a first boss is disposed, a circuit board whereon a hole is disposed in a position corresponding to the first boss, a fixing component for screwing in the first boss of the first case so as to fix the circuit board above the first case, a first elastic component disposed on a first side of the circuit board for supporting the circuit board above the first case, and a second elastic component disposed on a second side opposite to the first side of the circuit board for clamping the circuit board with the first elastic component. 
     These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic drawing of an electronic device according to a preferred embodiment of the present invention. 
         FIG. 2  is a sectional view of a fixing structure of the electronic device according to the first embodiment of the present invention. 
         FIG. 3  is a schematic drawing of a first elastic component around a first boss according to the first embodiment of the present invention. 
         FIG. 4  and  FIG. 5  are sectional views of a fixing structure of the electronic device according to a second embodiment of the present invention. 
         FIG. 6  is a sectional view of the first elastic component and a second elastic component connected to a circuit board according to the second embodiment of the present invention. 
         FIG. 7  is a sectional view of a fixing structure of the electronic device according to a third embodiment of the present invention. 
         FIG. 8  and  FIG. 9  are sectional views of a fixing structure of the electronic device according to a fourth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Please refer to  FIG. 1 ,  FIG. 1  is a schematic drawing of an electronic device  50  according to a preferred embodiment of the present invention. The electronic device  50  can be a computer device or a peripheral device, such as a storage device (hard disk drive, an optical disk drive, etc.), and so on. The electronic device  50  includes at least one fixing component  52  for screwing an outer case or internal components. The fixing component  52  can be a screw, and the number and the disposition of the fixing component  52  can depend on design demand. 
     Please refer to  FIG. 2 ,  FIG. 2  is a sectional view of a fixing structure  54  of the electronic device  50  according to the first embodiment of the present invention. The fixing structure  54  includes a first case  56  which can be a lower case of the electronic device  50 . At least one first boss  58  is disposed on the first case  56 . The fixing structure  54  further includes a circuit board  60  which can be a printed circuit board, a motherboard, and so on. At least one hole  62  is disposed on the circuit board  60  and located in a position corresponding to the first boss  58 . The fixing component  52  can be screwed in the first boss  58  on the first case  56  so as to fix the circuit board  60  above the first case  56 . The fixing structure  54  further includes a first elastic component  64  disposed on a first side  601  of the circuit board  60  for supporting the circuit board  60  above the first case  56 . The first elastic component  64  can be connected to the first boss  58 . For example, the first elastic component  64  can be a washer around the first boss  58 . Please refer to  FIG. 3 ,  FIG. 3  is a schematic drawing of the first elastic component  64  around the first boss  58  according to the first embodiment of the present invention. The first elastic component  64  can be made of rubber or can be a spring as a cushion to the circuit board  60 . The first elastic component  64  can be made of conductive material, such as conductive rubber, for ground connection. The fixing structure  54  further includes a second elastic component  66  disposed on a second side  602  opposite to the first side  601  of the circuit board  60  for clamping the circuit board  60  with the first elastic component  64 . The second elastic component  66  can be connected to the fixing component  52 . For example, the second elastic component  66  can be a washer disposed between a head of the fixing component  52  and the circuit board  60 . The second elastic component  66  can be made of rubber or can be a spring as a cushion to the circuit board  60 . The second elastic component  66  can be made of conductive material, such as conductive rubber, for ground connection. 
     The first elastic component  64  and the second elastic component  66  clamp the circuit board  60  together so that the first side  601  and the second side  602  of the circuit board  60  don&#39;t contact with rigid structure directly. Hence the circuit board  60  is capable of displacing up and down slightly as a suspension mechanism due to the cushion provided by the first elastic component  64  and the second elastic component  66 . When there is a plurality of the fixing components  52  for screwing the circuit board  60 , the first elastic components  64  and the second elastic components  66  for the plurality of the fixing components  52  clamp the circuit board  60  together so as to overcome tolerance of unbalanced screwing force of the plurality of the fixing components  52  and keep the circuit board  60  plane. 
     Please refer to  FIG. 4  and  FIG. 5 ,  FIG. 4  and  FIG. 5  are sectional views of a fixing structure  80  of the electronic device  50  according to a second embodiment of the present invention. The difference between the first embodiment and the second embodiment is that the first elastic component  64  and the second elastic component  66  are connected integrally. The first elastic component  64  and the second elastic component  66  can be formed as a washer for sheathing the fixing component  52 . The first elastic component  64  and the second elastic component  66  can be integrated with the circuit board  60  directly. Please refer to  FIG. 6 ,  FIG. 6  is a sectional view of the first elastic component  64  and the second elastic component  66  connected to the circuit board  60  according to the second embodiment of the present invention. The first elastic component  64  and the second elastic component  66  are formed as the washer for inserting into the hole  62  on the circuit board  60 . As shown in  FIG. 4 , then the fixing component  52  passes through the first elastic component  64  and the second elastic component  66  and is screwed in the first boss  58  on the first case  56 . Or as shown in  FIG. 5 , the first boss  58  on the first case  56  passes through the first elastic component  64  and the second elastic component  66 , and the fixing component  52  is screwed in the first boss  58 . Similarly, the first elastic component  64  and the second elastic component  66  clamp the circuit board  60  together so that the first side  601  and the second side  602  of the circuit board  60  don&#39;t contact with rigid structure directly. Hence the circuit board  60  is capable of displacing up and down slightly as a suspension mechanism due to the cushion provided by the first elastic component  64  and the second elastic component  66  so as to overcome tolerance of unbalanced screwing force of the plurality of the fixing components  52  and keep the circuit board  60  plane. 
     Please refer to  FIG. 7 ,  FIG. 7  is a sectional views of a fixing structure  90  of the electronic device  50  according to a third embodiment of the present invention. The difference between the second embodiment and the third embodiment is that the fixing structure  90  further includes a rigid washer  92  disposed inside the washer formed by the first elastic component  64  and the second elastic component  66  for sheathing the fixing component  52 . The rigid washer  92  is made of rigid material, such as plastic or metal material. The rigid washer  92  and the washer formed by the first elastic component  64  and the second elastic component  66  can be integrated with double injection method. The rigid washer  92  and the washer formed by the first elastic component  64  and the second elastic component  66  can be inserted into the hole  62  on the circuit board  60 , and then the fixing component  52  passes through the rigid washer  92  and is screwed in the rigid washer  92  and the first boss  58  on the first case  56 . The rigid washer  92  can strengthen the fixing effect of the fixing component  52  and can prevent the first elastic component  64  and the second elastic component  66  from wear. Similarly, the first elastic component  64  and the second elastic component  66  clamp the circuit board  60  together so that the first side  601  and the second side  602  of the circuit board  60  don&#39;t contact with rigid structure directly. Hence the circuit board  60  is capable of displacing up and down slightly as a suspension mechanism due to the cushion provided by the first elastic component  64  and the second elastic component  66  so as to overcome tolerance of unbalanced screwing force of the plurality of the fixing components  52  and keep the circuit board  60  plane. 
     Please refer  FIG. 8  and  FIG. 8 ,  FIG. 8  and  FIG. 9  are sectional views of a fixing structure  100  of the electronic device  50  according to a fourth embodiment of the present invention. As shown in  FIG. 8 , the fixing structure  100  includes a first case  102  which can be a lower case of the electronic device  50 . At least one first boss  104  is disposed on the first case  102 . The fixing structure  100  further includes a second case  106  which can be an upper case of the electronic device  50  for covering internal components of the electronic device  50 . At least one second boss  108  is disposed on the second case  106  and located in a position corresponding to the first boss  104  for passing through the hole  62  on the circuit board  60 . The second boss  108  on the second case  106  is assembled with the circuit board  60 , and then the first case  102  is assembled with the second case  106  and the circuit board  60 . Besides, as shown in  FIG. 9 , the first boss  104  passes through the hole  62  on the circuit board  60 . The first boss  104  on the first case  102  is assembled with the circuit board  60 , and then the second case  106  is assembled with the first case  102  and the circuit board  60 . The fixing component  52  passes through the first boss  104  on the first case  102  and the second boss  108  on the second case  106  so as to fix the circuit board  60  between the first case  102  and the second case  106 . Similarly, the first elastic component  64  disposed on the first side  601  of the circuit board  60  for supporting the circuit board  60  above the first boss  104 . The first elastic component  64  can be connected to the first boss  104 . For example, the first elastic component  64  can be a washer around the first boss  104 . The second elastic component  66  disposed on the second side  602  opposite to the first side  601  of the circuit board  60  for clamping the circuit board  60  with the first elastic component  64 . The second elastic component  66  can be connected to the second boss  108 . For example, the second elastic component  66  can be a washer around the second boss  108 . Similarly, the first elastic component  64  and the second elastic component  66  clamp the circuit board  60  together so that the first side  601  and the second side  602  of the circuit board  60  don&#39;t contact with rigid structure directly. Hence the circuit board  60  is capable of displacing up and down slightly as a suspension mechanism due to the cushion provided by the first elastic component  64  and the second elastic component  66  so as to overcome tolerance of unbalanced screwing force of the plurality of the fixing components  52  and keep the circuit board  60  plane. 
     In conclusion, the fixing structure of the present invention utilizes elastic components to clamp an upper side and a lower side of the circuit board so that the upper side and the lower side of the circuit board don&#39;t contact with rigid structure directly. Hence the circuit board is capable of displacing up and down slightly as a suspension mechanism due to the cushion provided by the elastic components so as to overcome tolerance of unbalanced screwing force of the plurality of the fixing components and keep the circuit board plane. The structure for preventing the circuit board from contacting with rigid structure directly is within the scope of the present invention. 
     In contrast to the prior art, the fixing structure of the present invention utilizes elastic components to clamp the circuit board so that the circuit board don&#39;t contact with rigid structure directly. The circuit board is capable of displacing up and down slightly as a suspension mechanism due to the cushion provided by the elastic components so as to overcome tolerance of unbalanced screwing force of the plurality of the fixing components and keep the circuit board plane. 
     Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.