Abstract:
An electric device includes a housing having an opening, a printed circuit board installed in the housing, a switch formed on the printed circuit board for enabling functions of the electric device, a faceplate for coving the opening of the housing, a keypad formed on a position of the faceplate corresponding to the switch for triggering the switch, and a fixing mechanism comprising a first fixing element extending from a side of the faceplate facing the printed circuit board, and a second fixing element extending from the printed circuit board for being combined with the first fixing element.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention provides an electric device capable of increasing switch precision, and more particularly, an electric device having a fixing mechanism for fixing the distance between a keypad and a switch, so as to increase switch precision.  
         [0003]     2. Description of the Prior Art  
         [0004]     Generally, when starting or stopping a function of an electric device, a user operates an inner switch of the electric device through a keypad on a faceplate of the electric device. That is, by pressing the keypad on the faceplate, the user indirectly triggers the switch, and activates or stops the function.  
         [0005]     For example, please refer to  FIG. 1 , which illustrates a schematic diagram of a prior art disc drive  100 . For simplicity,  FIG. 1  shows corresponding positions of a printed circuit board (PCB)  102 , a chassis  104 , a housing  106 , and a faceplate  108  in the disc drive  100 . Circuits laid on the PCB  102  perform functions of the disc drive  100 , such as disc reading, writing, etc. The PCB  102  is set on the chassis  104 . The housing  106  and the faceplate  108  protect inner structures of the disc drive  100 , such as the PCB  102 , laser devices, etc. The faceplate  108  is fixed on the housing  106  through a hook  113 , and is fixed on the chassis  104  through a hook  114 . The housing  106  includes a hole  117  corresponding to the hook  113 , and the chassis  104  also includes a hole  116  corresponding to the hook  114 . Therefore, the combination of the housing  106 , the faceplate  108 , and the chassis  104  encloses the disc drive  100  completely.  
         [0006]     Some functions of the disc drive  100  are enable and disable by triggering of keypads on the faceplate  108 , which is convenient for manufacturing and fabricating. Therefore, in  FIG. 1 , the PCB  102  includes a switch  112 , utilized for starting or stopping some operations of the circuits on the PCB  102 , such as disc injecting, ejecting, playing, etc. Corresponding to the switch  112 , the faceplate  110  includes a keypad  110  for triggering the switch  112 . That is, when a user presses the keypad  110 , the keypad  110  triggers the switch  112 , so as to perform a function. Therefore, there must be a suitable distance between the keypad  110  and the switch  112  such as distance  118  shows in  FIG. 1 , so as to prevent the keypad  110  from unnecessarily or incorrectly triggering the switch  112 . In such case, fabricating the disc drive  100  becomes complicated. The distance between the keypad  110  and the switch  112  should be equal to the distance  118 , so the position of the switch  112  on the PCB  102 , the position of the PCB  102  on the chassis, and even positions of the housing  106 , the faceplate  108 , the keypad  110 , the hooks  113 ,  114 , and the holes  116 ,  117  become critical. As a result, it is possible that circuits of the disc drive  100  work well, but the keypad  110  cannot trigger the switch  112  correctly.  
         [0007]     For example, if the keypad  110  and the switch  112  are too close such that the keypad  110  presses the switch  112  completely, then the keypad  110  always triggers the switch  112  even though the user does not press the keypad  110 . Oppositely, if the keypad  110  and the switch  112  are too far, then the keypad  110  is incapable of triggering the switch  112 . Therefore, in the prior art, a lot of viable factors must be considered when fabricating an electric device having a faceplate and keypads, causing an increase in production cost and fabrication difficulty.  
       SUMMARY OF THE INVENTION  
       [0008]     It is therefore a primary objective of the claimed invention to provide an electric device capable of increasing switch precision.  
         [0009]     The present invention discloses an electric device capable of increasing switch precision. The electric device comprises a housing having an opening, a printed circuit board installed in the housing, a switch formed on the printed circuit board for enabling functions of the electric device, a faceplate for coving the opening of the housing, a keypad formed on a position of the faceplate corresponding to the switch for triggering the switch, and a fixing mechanism comprising a first fixing element extending from a side of the faceplate facing the printed circuit board, and a second fixing element extending from the printed circuit board for being combined with the first fixing element.  
         [0010]     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  
       [0011]      FIG. 1  illustrates a schematic diagram of a prior art disc drive.  
         [0012]      FIG. 2  illustrates a sectional diagram of an electric device capable of increasing switch precision in accordance with the first embodiment of the present invention.  
         [0013]      FIG. 3  illustrates a sectional diagram of a disc drive in accordance with the third embodiment of the present invention.  
         [0014]      FIG. 4  illustrates a vertical view diagram of a disc drive shown in  FIG. 3 .  
         [0015]      FIG. 5  illustrates a sectional diagram of an electric device capable of increasing switch precision in accordance with the second embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0016]     Please refer to  FIG. 2 , which illustrates a sectional diagram of an electric device capable of increasing switch precision in accordance with the first embodiment of the present invention. For simplicity,  FIG. 2  shows corresponding positions of a PCB  200 , a faceplate  202 , a switch  204 , a keypad  206 , a hook  208 , and a groove  210 . Circuits laid on the PCB  200  perform functions of the electric device. The faceplate  202  is set in front of the electric device, utilized for protecting the electric device. The switch  204  is set on the PCB  200  for starting or stopping some functions. The keypad  206  is set on a position of the faceplate  202  corresponding to the switch  204 . A user can press the keypad  206  to trigger the switch  204 , so as to perform the functions. A combination of the hook  208  and the groove  210  form a fixing mechanism of the present invention, utilized for fixing a distance between the faceplate  202  and the PCB  200 . One end of the hook  208  extends from a side of the faceplate  202  facing the PCB  200 , while the other end of the hook  208  is a hook structure fastening on the groove  210  of the PCB  200 . Therefore, once the hook structure of the hook  208  fastens on the groove  210 , the distance between the faceplate  202  and the PCB  200  are fixed. As a result, the only factors affecting the distance between the keypad  206  and the switch  204  are the position of the switch  204  on the PCB  200  and the position of the keypad  206  on the faceplate  202 . In short, the hook  208  firms up the distance between the faceplate  202  and the PCB  200  to decrease factors affecting the distance between the keypad  206  and the switch  204 , so as to decrease production cost and fabrication difficulty, and increase yield.  
         [0017]     Other than the fixing mechanism of the hook  208  and the groove  210 , please refer to  FIG. 5 , which illustrates a sectional diagram of an electric device capable of increasing switch precision in accordance with the second embodiment of the present invention. For simplicity,  FIG. 5  shows corresponding positions of a PCB  500 , a faceplate  502 , a switch  504 , a keypad  506 , a bar  508 , and a flange  510  in the electric device. Circuits laid on the PCB  500  perform functions of the electric device. The faceplate  502  is set in front of the electric device, utilized for protecting the electric device. The switch  504  is set on the PCB  500  for starting or stopping some functions. The keypad  506  is set on a position of the faceplate  502  corresponding to the switch  504 . A user can press the keypad  506  to trigger the switch  504 , so as to perform the functions. A combination of the bar  508  and the flange  510  forms a fixing mechanism of the present invention, utilized for fixing a distance between the faceplate  502  and the PCB  500 . One end of the bar  508  extends from a side of the faceplate  502  facing the PCB  500 , while the other end of the bar  508  is a fillister structure fastening on the flange  510  of the PCB  500 . Therefore, once the flange  510  fastens on the fillister of the bar  508 , the distance between the faceplate  502  and the PCB  500  are fixed. As a result, the only factors affecting the distance between the keypad  506  and the switch  504  are the position of the switch  504  on the PCB  500  and the position of the keypad  506  on the faceplate  502 . In short, the bar  508  firms up the distance between the faceplate  502  and the PCB  500  to decrease factors affecting the distance between the keypad  506  and the switch  504 , so as to decrease production cost and fabrication difficulty, and increase yield.  
         [0018]     In the prior art, a lot of factors affecting the distance between the keypad and the switch must be considered, so that the keypad may always trigger the switch, or the keypad may not be able to trigger the switch. However, in the present invention, the only factors affecting the distance between the keypad and the switch are the position of the switch on the PCB and the position of the keypad on the faceplate, and in fact, these two factors do not cause any effect as mass manufacturing technologies (opendie and plating for example) develop widely.  
         [0019]     As to an electric device having multiple keypads, maintaining distances between each keypad and a corresponding switch becomes more difficult. The present invention can fix a distance between a faceplate and a PCB in the electric device through a fixing mechanism to decrease factors affecting the distance between the keypads and the corresponding switches. For example, please refer to  FIG. 3  and  FIG. 4 .  FIG. 3  illustrates a sectional diagram of a disc drive  300  in accordance with the third embodiment of the present invention, and  FIG. 4  illustrates a vertical view diagram of the disc drive  300 . In the disc drive  300 , a PCB  302  is set on a chassis  304 . Circuits laid on the PCB  302  perform functions of the disc drive  300 , such as disc reading, writing, etc. The faceplate  308  is set in front of the disc drive  300 , and includes keypads  310 ,  318 ,  322 , and  326  corresponding switches  312 ,  320 ,  324 , and  328  of the PCB  302 . The switches  312 ,  320 ,  324 , and  328  are utilized for starting or stopping some functions of the disc drive  300 , such as disc injecting, ejecting, fast-forwarding, rewinding, playing, etc. The hooks  314 ,  330  and the grooves  316 ,  322  are formed according to the fixing mechanism shown in  FIG. 2 . One end of each of the hooks  314  and  330  extends from the faceplate  308 , while the other end of each of the hooks  314  and  330  is a hook structure fastening on one of the grooves  316  and  322  on the PCB  302 . The hooks  314  and  330  can firm up the distance between the faceplate  308  and the PCB  302 , and the faceplate  308  is also fixed on a housing (not shown in  FIG. 3  and  FIG. 4 ) of the disc drive  300  through other hooks. Therefore, the distance between the faceplate  308  and the PCB  302  can be fixed by the combination of the hooks  314 ,  330 , and the grooves  316 ,  322 . As a result, factors affecting distances between the keypads  310 ,  318 ,  322 ,  326  and the switches  312 ,  320 ,  324 ,  328  can be decreased, so as to decrease production cost, increase yield, and simplify the enclosing procedure.  
         [0020]     In the present invention, elements of the fixing mechanism are exemplified for fixing the distance between the faceplate and the PCB. Various modifications could be made without departing from the spirit of the present invention. Moreover, electric devices having keypads on faceplates for triggering switches on PCBs, such as disc drives, display devices, etc., can adopt the present invention. In summary, the present invention firms up the distance between the faceplate and the PCB to decrease factors affecting the distance between the keypad and the switch, so as to decrease production cost and fabrication difficulty, and increase yield.  
         [0021]     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.