Patent Publication Number: US-2004052061-A1

Title: Mounting structure of wireless module having excellent productivity

Description:
BACKGROUND OF THE INVENTION  
       [0001] 1. Field of the Invention  
       [0002] The present invention relates to a mounting structure of a wireless module suitable to be used in a wireless transceiver such as a potable phone or a personal computer.  
       [0003] 2. Description of the Related Art  
       [0004] The conventional mounting structure of a wireless module will be explained with reference to the drawings wherein FIG. 3 is a perspective view illustrating a wireless module relating to the conventional mounting structure of a wireless module, and FIG. 4 is a perspective view illustrating the conventional mounting structure of the wireless module.  
       [0005] Next, a configuration of the conventional mounting structure of the wireless module will be described with reference to FIGS. 3 and 4. In a circuit board  51  constructed by laminating one sheet or a plurality of sheets, electrical components  52  such as chip type resistors or capacitors including semiconductor components are mounted on its upper surface wherein wiring patterns (not shown) are formed, so that a desired electric circuit comprising a receiving/transmitting circuit is formed.  
       [0006] A cover  53  made of a solderable metal plate has a box-shaped cover portion  53   a  and a plurality of attaching pieces  53   b  projected downward from the lower end of the cover portion  53   a . In a state wherein the cover portion  53   a  of the cover  53  covers the electrical components  52 , the cover  53  is attached to the circuit board  51  by soldering solders  55  of the attaching pieces  53   b  to side electrodes  54  provided in the circuit board  51 .  
       [0007] With this configuration, a wireless module M 2  is formed (for example, see Japanese Unexamined Patent Application Publication No. 1999-31893).  
       [0008] With such wireless module M 2 , the circuit board  51 , as shown in FIG. 4, is put on a motherboard  56 , the circuit board  51  is mounted on conductive patterns  57  of the motherboard  56  with solders  58 , and thus the circuit board  51  is electrically connected to the motherboard  56 .  
       [0009] In this state, the solders  55  for attaching the cover  53  are externally exposed, and thus the cover  53  can be easily separated by melting the solders  55 . As a result, violation such as exchange of memory or alteration of output power in the wireless module M 2  becomes easy.  
       [0010] Therefore, conventionally in order to prevent such violation, as shown in FIG. 4, a protective cover  59  for covering the wireless module M 2  is provided on the motherboard  56 . The protective cover  59  is attached to the motherboard  56  with special screws (not shown) which can be attached and detached by means of a special tool.  
       [0011] In the conventional mounting structure of the wireless module, since the protective cover  59  for covering the wireless module M 2  and the special screws for attaching the protective cover  59  to the motherboard  56  are required in order to prevent the violation. Thus, the prior art has problems in that the cost increases due to more components, has some difficulties in attaching the protective  59 , and thus lowers the productivity.  
       SUMMARY OF THE INVENTION  
       [0012] Therefore, it is an object of the present invention to provide a mounting structure of a wireless module having low cost and excellent productivity.  
       [0013] As a first solving means for solving the above problems, a mounting structure of a wireless module is provided, the mounting structure comprising: a circuit board having electrical components including semiconductor components mounted on its upper surface; a cover attached to the circuit board while covering the electrical components; and a motherboard for mounting the circuit board thereon, wherein the cover has a box-shaped cover portion and one or a plurality of leg portions projected downward from the cover portion, wherein first through holes for inserting the leg portions are provided in the circuit board, and second through holes for inserting the leg portions are provided in the motherboard, and wherein the leg portions are soldered to the circuit board and the motherboard at the first and second through holes or at positions close to the first and second through holes in a state that the leg portions are inserted into the first and second through holes, respectively.  
       [0014] Further, as a second solving means, the circuit board is put on the motherboard to overlap each other.  
       [0015] Further, as a third solving means, conductors are provided on the walls of the first and second through holes, and the leg portions are soldered to the conductors.  
       [0016] Further, as a fourth solving means, the leg portions extend in a straight line. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0017]FIG. 1 is a perspective view illustrating a mounting structure of a wireless module according to the present invention;  
     [0018]FIG. 2 is a cross-sectional view illustrating essential parts of the mounting structure of the wireless module according to the present invention;  
     [0019]FIG. 3 is a perspective view illustrating a wireless module relating to the conventional mounting structure of a wireless module; and  
     [0020]FIG. 4 is a perspective view illustrating the conventional mounting structure of the wireless module. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0021] A mounting structure of a wireless module according to the present invention will be explained with reference to the drawings wherein FIG. 1 is a perspective view illustrating a mounting structure of a wireless module according to the present invention, and FIG. 2 is a cross-sectional view illustrating essential parts of the mounting structure of the wireless module according to the present invention.  
     [0022] Next, a configuration of the mounting structure of the wireless module according to the present invention will be described with reference to FIGS. 1 and 2. In a circuit board  1  constructed by laminating one sheet or a plurality of sheets, electrical components  2  such as chip type resistors or capacitors including semiconductor components are mounted on its upper surface wherein wiring patterns (not shown) are formed, so that a desired electric circuit comprising a receiving/transmitting circuit is formed.  
     [0023] Further, a plurality of through holes la is provided in the circuit board  1 , and solderable conductors  3  are provided on the walls of the through holes  1   a.    
     [0024] Then, although not shown herein, connection conductors are provided on the lower surface or side surface of the circuit board  1 , and thus the circuit board  1  can be electrically connected to the outside thereof through the connection conductors.  
     [0025] A cover  4  made of a solderable metal plate comprises a box-shaped cover portion  4   a  and a plurality of leg portions  4   b  provided at corners of the cover portion  4   a  and projected downward from the lower end of the cover portion  4   a  in a straight line. In a state wherein the cover portion  4   a  of the cover  4  covers the electrical components  2 , the leg portions  4   b  are inserted into the through holes  1   a , and the leg portions  4   b  are attached to the circuit board  1  by soldering solders  5  to the conductors  3 .  
     [0026] With this configuration, a wireless module M 1  is formed.  
     [0027] Further, a motherboard  6  for mounting the circuit board  1  thereon has conductive patterns  7  and a plurality of through holes  6   a , and solderable conductors  8  are provided on the walls of the through holes  6   a.    
     [0028] Then, the circuit board  1  is put on the motherboard  6  to overlap each other, and the leg portions  4   b  are inserted into the through holes  6   a.    
     [0029] In this state, by soldering the connection conductors of the circuit board  1  to the conductive patterns  7 , the circuit board  1  is electrically connected to the motherboard  6 , and the leg portions  4   b  are attached to conductors  8  with solders  9 .  
     [0030] The soldering of the circuit board  1  to the motherboard  6  and the soldering of the leg portions  4   b  to the conductors  8  with the solders  9  are performed in the simultaneous process by using a cream solder.  
     [0031] Furthermore, although the above embodiment has been described that the plurality of leg portions  4   b  are formed, only one leg portion may be formed.  
     [0032] Further, although the leg portions  4   b  have been described to extend in a straight line, the leg portions  4   b  inserted into the through holes  1   a  may be bent into an L shape on the lower surface side of the circuit board  1 , and then the end of the L shape may be inserted into the through holes  6   a  of the mother substrate  6 .  
     [0033] Further, the leg portions  4   b  may be soldered at positions close to the through holes  1   a ,  6   a.    
     [0034] The mounting structure of the wireless module according to the present invention comprises the circuit board having the electrical components including the semiconductor components mounted on its upper surface; the cover attached to the circuit board while covering the electrical components; and the motherboard for mounting the circuit board thereon, wherein the cover has the box-shaped cover portion and one or a plurality of leg portions projected downward from the cover portion, wherein first through holes for inserting the leg portions are provided in the circuit board, and second through holes for inserting the leg portions are provided in the motherboard, and wherein the leg portions are soldered to the circuit board and the motherboard at the first and second through holes or at positions close to the first and second through holes in a state that the leg portions are inserted into the first and second through holes, respectively. Accordingly, the cover also serves as a conventional protective cover. Therefore, this invention has less components than the conventional art, decreases the cost, simplifies the mounting process of the cover, and thus provides excellent productivity.  
     [0035] Further, since the leg portions are attached in a state wherein the leg portions are inserted into the first and second through holes, it is difficult to peel off the solders of the leg portions. Thus, it is possible to surely prevent the violation.  
     [0036] Further, since the circuit board is put on the motherboard to overlap each other, it becomes more difficult to peel off the solders of the leg portions. Thus, it is possible to prevent the violation with more certainty.  
     [0037] Further, since the conductors are provided on the walls of the first and second through holes and the leg portions are soldered to the conductors, it becomes more difficult to peel off the solders of the leg portions. Thus, it is possible to prevent the violation with more certainty.  
     [0038] Further, since the leg portions extend in a straight line, the cover can be manufactured simply, and it is possible to easily attach the cover to the circuit board and the motherboard, which provides excellent productivity.