Patent Publication Number: US-2003223204-A1

Title: Electronic apparatus, printed wiring board, and connector fixing method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001] This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2002-160683, filed May 31, 2002.  
       BACKGROUND OF THE INVENTION  
       [0002] 1. Field of the Invention  
       [0003] The present invention relates to a structure and method of fixing a connector to a printed wiring board, and a printed wiring board to which a connector is fixed. More particularly, the invention relates to a structure and method of fixing various types of interface connectors, such as a power supply input connector including a DC-IN jack, a keyboard connector, a mouse connector, a USB connector, IEEE 1394 connector, a video input connector, a video output connector and an audio jack, to a printed wiring board of an electronic apparatus, and a printed wiring board to which the connector is fixed.  
       [0004] 2. Description of the Related Art  
       [0005] In an electronic apparatus such as a portable computer, a DC-IN connector  21  (DC-IN jack) for connecting a power supply plug of a DC adapter, for example, as shown in FIG. 2 is mounted by soldering it to a printed wiring board.  
       [0006]FIG. 11 shows conventional fixing pads  83   a,    83   b,  and  83   c  for mounting a connector  21  on a printed wiring board  81 . FIG. 12 and FIG. 13 are enlarged sectional views of a part at which a fixing lead (a soldering terminal)  91  of the connector  21  is connected to the conventional fixing pad  83 . As shown in FIG. 11, provided on the printed wiring board  81  is three fixing pads  83   a,    83   b  and  83   c  for mounting the connector  21 . The pads  83   a,    83   b  and  83   c  are provided penetrating through the printed wiring board  81  or provided on the mounting surface  82   a  and backside  82   b  of the printed wiring board  81 .  
       [0007] When mounting the connector  21  on the printed wiring board  81 , as shown in FIG. 12, insert a fixing lead  91  of the connector  21  into a hole  84  of each pad  83 , and fix the lead to the pads  83   a,    83   b  and  83   c  with solder  92 .  
       [0008] However, in the above-mentioned conventional connector fixing structure, when a pry force is applied to the connector  21  through a power supply plug with the power supply plug inserted into the connector  21 , a pry force  93  is applied to the lead  91  of the connector  21 , as shown in FIG. 13, and the pad  83  is peeled off from the printed wiring board  81  by this pry force  93 . FIG. 13 shows a peeled-off portion  94  formed by the pry force  93  on both sides of the pad  83 .  
       [0009] When the pad  83  is peeled off from the printed wiring board  81  as shown above, fixing of the connector  21  is affected, and in the worst case, the connector  21  is separated from the printed wiring board  81 .  
       BRIEF SUMMARY OF THE INVENTION  
       [0010] The electronic apparatus according to one aspect of the present invention comprises a wiring board; a connector, provided on the wiring board, configured to be connected to an external device and transmit signal between the external device and the electronic apparatus; a pad, provided on the wiring board, configured to be connected to the connector; and a through hole land provided through the pad on the wiring board to fix the pad to the wiring board. 
     
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
     [0011] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.  
     [0012]FIG. 1 is a plan view showing the pattern layout of a printed wiring board according to a first embodiment of the present invention;  
     [0013]FIG. 2 is a perspective view showing the connector mounting state in the first embodiment;  
     [0014]FIG. 3 is a sectional view showing the connector mounting structure in the first embodiment;  
     [0015]FIG. 4 is a plan view showing the pattern layout of the printed wiring board in a second embodiment of the present invention;  
     [0016]FIG. 5 is a perspective view showing the connector mounting state in the second embodiment;  
     [0017]FIG. 6 is a plan view showing the pattern layout of a printed wiring board in a third embodiment of the present invention;  
     [0018]FIG. 7 is a perspective view showing the connector mounting state in the third embodiment;  
     [0019]FIG. 8 to FIG. 10 are plan views showing a modification example of a pad to fix a connector to a printed wiring board;  
     [0020]FIG. 11 is a plan view showing the pattern layout of the connector mounting part of a conventional printed wiring board;  
     [0021]FIG. 12 is a sectional view showing a conventional connector mounting structure; and  
     [0022]FIG. 13 is a sectional view showing the state of peeling off of a fixing pad in a conventional connector mounting structure. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
     [0023] Hereinafter, preferred embodiments of the present invention will be explained with reference to the accompanying drawings.  
     [0024] First, a first embodiment of the present invention will be explained with reference to FIG. 1 to FIG. 3. The first embodiment shows an example of applying the present invention to a DC-IN connector mounting part.  
     [0025]FIG. 1 is a plan view showing the pattern layout of a printed wiring board according to the first embodiment of the present invention. FIG. 2 is a perspective view showing the connector mounting state in the first embodiment. FIG. 3 is a sectional view showing the connector mounting structure in the first embodiment.  
     [0026] As shown in FIG. 1, three substantially rectangular fixing pads  13   a,    13   b,    13   c  (hereinafter, generically called a pad  13 ) for fixing/mounting a DC-IN connector  21  shown in FIG. 2 to/on a printed wiring board  11  are provided on a mounting surface  12   a  and backside  12   b  of a printed wiring board  11  (FIG. 3).  
     [0027] At almost the center of each pad  13 , elliptical holes.  14   a,    14   b,    14   c  (hereinafter generically called a hole  14 ) for inserting leads  23   a,    23   b,    23   c  (soldering terminals) (hereinafter, generically called a lead  23 ) for fixing the connector  21  are provided penetrating through the printed wiring board  11 . For example, each pad  13  is formed by plating a copper foil, and the plated parts of the mounting surface  12   a  and backside  12   b  of the printed wiring board  11  are connected through the hole  14 .  
     [0028] When mounting the connector  21  on the printed wiring board  11 , the lead  23  of the connector  21  is inserted into the hole  14  of each pad  3 , and each lead  23  is fixed to the pad  13  with solder  24 . Thereby, the connector  21  is fixed to the printed wiring board  11  through the pad  13 .  
     [0029] In this embodiment, each pad  13  is firmly fixed to the printed wiring board  13  by providing a through hole land TH at four corners of each pad  13 , preventing the pad  13  from being peeled off from the printed wiring board  11  when a pry force is applied to the lead.  
     [0030] The through hole land TH is formed by connecting a part of the mounting side and a part of the backside of the pad  13  through the hole penetrating through the printed wiring board  11 . This prevents the pad  13  from being peeled off from the printed wiring board  11 , even if a force is applied to the pad  13  in the direction separating from the printed wiring board when a pry force is applied to the lead  23 , and the connector  21  is firmly fixed to the printed wiring board  11   b.    
     [0031] Namely, when an external deflecting force is applied to the connector  21  through the power supply plug while the power supply plug is being inserted into the connector  21  mounted on the mounting surface  12  of the printed wiring board, a pry force is applied to the lead  23  of the connector  21 , and this pry force works in the direction to peel off the pad  13  from the printed wiring board  11 . At this time, the through hole land TH provided at four corners of the pad  13  connects the parts of the mounting surface  12   a  and backside  12   b,  and the pad  13  is prevented from being peeled off by the pry force stress.  
     [0032] As described above, this embodiment makes it possible to fix the connector  21  to the printed wiring board  11  at a low cost and with a simple structure without using additional parts such as metal fittings for fixing the connector  21  to the printed wiring board  11 .  
     [0033] Next, the second embodiment of the present invention will be explained with reference to FIG. 4 and FIG. 5. The second embodiment illustrates an example of applying the present invention to a USB connector mounting part.  
     [0034]FIG. 4 is a plan view showing the pattern layout of the printed wiring board in the second embodiment of the present invention. FIG. 5 is a perspective view showing the connector mounting state in the second embodiment.  
     [0035] As shown in FIG. 4, three substantially rectangular fixing pads  33   a,    33   b,    33   c  for fixing/mounting a USB connector  41  shown in FIG. 5 to/on a printed wiring board  31  are provided on the mounting surface  32   a  and backside  32   b  (not shown) of the printed wiring board  31 .  
     [0036] At almost the center of each pad  33 , elliptical holes  34   a,    34   b,    34   c  for inserting a lead  42  for fixing the connector  41  are provided penetrating through the printed wiring board  31 . Each pad  33  has a through hole land TH at four corners, and fixed firmly to the printed wiring board  31  as in the above-mentioned first embodiment.  
     [0037] On the mounting surface  32   a  of the printed wiring board  31 , four wires P 1 -P 4  for electrically connecting terminals TP 1 -TP 4  of the connector  41  are printed.  
     [0038] When mounting the connector  41  on the printed wiring board  31 , insert the lead  42  of the connector  41  into the hole  34  of each pad  33 , and fix each lead  42  to the pad  33  with solder  24 . Thereby, the connector  41  is fixed to the printed wiring board  31  through the pad  33 .  
     [0039] Also in this embodiment, as a through hole land TH is provided at four corners of each pad  33 , the same effect as that in the first embodiment can be obtained.  
     [0040] Next, the third embodiment of the present invention will be explained with reference to FIG. 6 and FIG. 7. The third embodiment illustrates an example of applying the present invention to an IEEE 1394 connector mounting part.  
     [0041]FIG. 6 is a plan view showing the pattern layout of a printed wiring board in the third embodiment of the present invention. FIG. 7 is a perspective view showing the connector mounting state in the third embodiment.  
     [0042] As shown in FIG. 6, two substantially rectangular fixing pads  53   a  and  53   b  for fixing/mounting an IEEE 1394 connector  61  shown in FIG. 7 to/on a printed wiring board  51  are provided on the mounting surface  52   a  and backside  52   b  (not shown) of the printed wiring board  51 .  
     [0043] At almost the center of each pad  53 , elliptical holes  54   a  and  54   b  for inserting a lead  62  for fixing the connector  61  are provided penetrating through the printed wiring board  51 . Each pad  53  has a through hole land TH at four corners, and fixed firmly to the printed wiring board  51  as in the above-mentioned first and second embodiments.  
     [0044] On the mounting surface  52   a  of the printed wiring board  51 , four wires P 1 -P 4  for electrically connecting terminals TP 1 -TP 4  of the connector  61  are printed.  
     [0045] When mounting the connector  61  on the printed wiring board  51 , insert the lead  62  of the connector  61  into the hole  54  of each pad  53 , and fix each lead  62  to the pad  53  with solder  64 . Thereby, the connector  61  is fixed to the printed wiring board  51  through the pad  53 .  
     [0046] Also in this embodiment, as a through hole land TH is provided at four corners of each pad  53 , the same effect as that in the first and second embodiments can be obtained.  
     [0047] Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.  
     [0048] For example, in the above-mentioned embodiments, the pad for fixing the lead of the connector to the printed wiring board is substantially rectangular, but the pad is not limited to the rectangular form. Circular form as shown in FIG. 8, elliptical form as shown in FIG. 9, or elongate form as shown in FIG. 10 is also permitted. In this case, the same effect of preventing peeling off as that in the above-mentioned embodiments can be obtained by providing a plurality of through hole lands TH at fixed intervals along the edge of a pad. The least necessary number of through hole land is two, and the total number can be optionally set.  
     [0049] Further, in the above-mentioned embodiments, as shown in FIG. 3 for example, the pad can be firmly fixed to the printed wiring board by flowing the solder  24  into the through hole land TH. Namely, as the through hole land TH is formed by plating copper foil so as to connect the mounting surface and the backside through the hole formed penetrating through the printed wiring board, as mentioned above, the land form is cylindrical at the hole. Thus, by filling this cylindrical part with the solder  24 , the through hole land TH can be shaped like a bar increasing the strength. Further, it is also possible to connect the solder on the mounting surface and the solder on the backside of the printed wiring board through the solder  24  filled in the through hole land, and the pad can be fixed to the printed wiring board only by soldering.  
     [0050] Moreover, the present invention is applicable not only to the above-mentioned embodiments, but also the structure for fixing various external interface connectors such as a keyboard connector, a mouse connector, a video input connector, a video output connector and an audio jack.