Patent Publication Number: US-2017359926-A1

Title: Electromagnetic interference shielding configuration of electronic device

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention generally relates to an electromagnetic interference shielding configuration and, in particular to an electromagnetic interference shielding configuration that is provided separately in an electronic device. 
     Description of Prior Art 
     Generally speaking, electronic components of motors or electronic devices will generate electromagnetic noises during operating. Moreover, electromagnetic noises outside the device would cause abnormal operation to the device via radiation or conduction. 
     In tradition, in order to prevent the radiation or conduction noises from affecting the surrounding electricity usage, the solution is to add a filter circuit on a mainboard for filtering the electromagnetic noises. However, the filter circuit might be affected by the electromagnetic interference of an external device that causes instability problems of the filter. Besides, disposing a filter circuit on a mainboard will take up space on the mainboard and further affect arrangement of other electronic components. 
     In view of the above drawbacks, the Inventor proposes the present invention based on his expert knowledge and elaborate researches in order to solve the problems of prior art. 
     SUMMARY OF THE INVENTION 
     Accordingly, an object of the present invention is to provide an electromagnetic interference shielding configuration of an electronic device for an EMI filter will not have electromagnetic interferences with external electronic components and provide a stable operation of the electronic device. 
     Accordingly, another object of the present invention is to provide an electromagnetic interference shielding configuration of an electronic device, in which an EMI filter is disposed on another circuit board; therefore, the deposition of the EMI filter will not take up space on the mainboard, and the depositions of other electronic components can be arranged easily. 
     In order to achieve the object mentioned above, the present invention provides an electromagnetic interference shielding configuration of electronic device comprising a housing, a connecting circuit board, at least one EMI filter and a shielding component. The housing has an accommodating space and a shielding space. The connecting circuit board is disposed in the shielding space and electrically conducted to the mainboard through the connecting circuit board. The EMI filter is disposed on the connecting circuit board and electrically conducted to the mainboard through the connecting circuit board. The shielding component combines with the housing and covers the shielding space. 
     Comparing to the prior art, the electromagnetic interference shielding configuration of electronic device of the present invention is formed with an independent room in the shielding space. The shielding space is disposed for placing the EMI filter and its connecting circuit board individually, and then a shielding component covers the shielding space. Therefore, a better shielding effect is provided for the EMI filter in the shielding space, and then the EMI filter will not be affected by external electromagnetic interference during operation so that a normal operation will be performed. Moreover, because the EMI filter of the present invention is disposed in another circuit board, the deposition of the EMI filter will not take up space on the mainboard, and the depositions of other electronic components can be arranged easily. 
    
    
     
       BRIEF DESCRIPTION OF DRAWING 
       The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself, however, may be best understood by reference to the following detailed description of the invention, which describes a number of exemplary embodiments of the invention, taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective schematic view of an electromagnetic interference shielding configuration of electronic device of the present invention; 
         FIG. 2  is a partial perspective exploded schematic view of an electromagnetic interference shielding configuration of electronic device of the present invention; 
         FIG. 3  is a top view of an electromagnetic interference shielding configuration of electronic device of the present invention; 
         FIG. 4  is a perspective schematic view of another embodiment of an electromagnetic interference shielding configuration of electronic device of the present invention; 
         FIG. 5  is a partial top view of another embodiment of an electromagnetic interference shielding configuration of electronic device of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In cooperation with attached drawings, the technical contents and detailed description of the invention are described thereinafter according to a number of preferable embodiments, being not used to limit its executing scope. Any equivalent variation and modification made according to appended claims is all covered by the claims claimed by the present invention. 
     Please refer to  FIG. 1  to  FIG. 3 , which depict a perspective schematic view, a partial perspective exploded schematic view and a top view of an electromagnetic interference shielding configuration of an electronic device of the present invention. An electromagnetic interference shielding configuration of an electronic device of the present invention includes a housing  10 , a connecting circuit board  20 , at least one EMI filter  30  and a shielding component  40 . The EMI filter  30  is disposed on the connecting circuit board  20 . The connecting circuit board  20  is installed in the housing  10 . The shielding component  40  covers the EMI filter  30  for providing an electromagnetic interference shielding configuration of an electronic device  1 . 
     As shown in  FIG. 1 , the housing  10 , preferably, is a metal shell. The housing  10  includes a plurality of plates  11 , and the plates  11  are enclosed to form an accommodating space  100  and a shielding space  101 ; a mainboard  12  is disposed in the accommodating space  100 . Please refer to  FIG. 2 , the shielding space  101  is concavely formed in the accommodating space  100 , and the mainboard  12  is located at a side of the shielding space  101 . In the present embodiment, the shielding space  101  is, but not limited to, a rectangular trough. The shielding space  101  can be provided in any shape that is suited for accommodating the connecting circuit board  20  and the EMI filter  30 . 
     It is worth of notice that the method of forming the housing  10  is not limited. In real practice, the housing  10  is integrally formed such as casting etc. 
     The connecting circuit board  20  is used for disposing the EMI filter  30  separately. The connecting circuit board  20  is disposed in the shielding space  101  and electrically connected with the mainboard  12 . 
     Moreover, the EMI filter  30  is a circuit configured by one or a plurality of electromagnetic (inductive) components combining with a plurality of capacitors. In an embodiment of the present invention, the EMI filter  30  is placed on the connecting board  20 , and the EMI filter  30  is electrically conducted to the mainboard  12  through the connecting circuit board  20 . More specifically, the EMI filter  30  is connected with the input port or the output port of the circuit; the EMI filter  30  is provided for preventing the conduction and radiation noises that have influence on the surrounding environment of electricity. 
     In an embodiment of the present invention, the mainboard  12  has an input port  121 , and the EMI filter  30  is electrically conducted to the input port  121 . 
     The shielding component  40  combines with the housing  10  and covers the EMI filter  30 ; preferably, the shielding component  40  covers the shielding space  101 . In the present invention, the shielding component  40  is a metal sheet. The shielding component  40  covers the shielding space  101  and provides a shielding effect for the EMI filter  30  disposed in the shielding space  101 . Therefore, the EMI filter  30  will not be affected by external electromagnetic interference during operation so that a normal operation will be performed. 
     In an embodiment of the present invention, the electromagnetic interference shielding configuration of the electronic device  1  further includes a second EMI filter  50 . Furthermore, the second EMI filter  50  is disposed on the connecting circuit board  20  and located at a side of the EMI filter  30 . The second EMI filter  50  is also electrically conducted to the mainboard  12  through the connecting circuit board  20 . In more detail, the mainboard  12  has an output port  122 , and the second EMI filter  50  is electrically conducted to the output port  122 . 
     In an embodiment of the present invention, the housing  10  further includes a cover  13 . The cover  13  seals the accommodating space  100  as to provide a shielding effect for the components in the accommodating space  100 . 
     As shown in  FIG. 3 , the electromagnetic interference shielding configuration of the electronic device  1  further includes a plurality of conducting wires  60 . The connecting circuit board  20  is electrically connected with the mainboard  12  through the conducting wires  60 . In the present embodiment, the electronic device  1  is an inverter, and electronic components such as a PWM control unit and an oscillator are provided in the accommodating space  100 . 
     It is worth of notice that, the electrical connection of the connecting circuit board  20  and the mainboard  12  is not limited to the conducting wires. In real practice, the electrical connection of the connecting circuit board  20  and the mainboard  12  can be achieved by connectors. 
     It is also worth of notice that, when the connecting circuit board  20 , the EMI filter and the second EMI filter  50  are disposed in the shielding space  101 , the shielding space  101  can be filled with sealant (not shown). The sealant can be a heatsink plaster that is used to dissipate heat of the connecting circuit board  20 , the EMI filter  30  and the second EMI filter  50 . 
     Please also refer to  FIG. 4  and  FIG. 5 , which depict a perspective schematic view and a partial top view of another embodiment of an electromagnetic interference shielding configuration of electronic device  1   a  of the present invention. The present embodiment is substantially the same as the first embodiment. An electromagnetic interference shielding configuration of electronic device  1   a  includes a housing  10   a,  a connecting circuit board  20   a,  at least one EMI filter  30   a,  a shielding component  40   a  and a second EMI filter  50   a.  The housing  10   a  has an accommodating space  100   a  and a shielding space  101   a.  A mainboard  12   a  is disposed in the accommodating space  100   a.  The EMI filter  30   a  and the second EMI filter  50   a  are disposed on the connecting circuit board  20   a,  and the connecting circuit board  20   a  is installed in the shielding space  101   a.  The shielding component  40   a  covers the EMI filter  30   a  and the second EMI filter  50   a  for providing an electromagnetic interference shielding configuration of an electronic device  1   a.  A difference between the two embodiments is the disposition of the shielding space  101   a.    
     In the present embodiment, the mainboard  12   a  has an input port  121   a  and an output port  122   a.  Besides, the EMI filter  30   a  is electrically connected to the input port  121   a,  and the second EMI filter  50   a  is electrically connected to the output port  122   a.  In addition, the electromagnetic interference shielding configuration of electronic device  1   a  further includes a plurality of conducting wires  60   a,  and the connecting circuit board  20   a  is electrically connected with the mainboard  12   a  through the conducting wires  60   a;  that is, the EMI filter  30   a  and the second EMI filter  50   a  are electrically connected to the input port  121   a  and the output port  122   a  through the conducting wires  60   a  for providing an electromagnetic interference shielding effect. 
     In one embodiment of the present invention, the housing  10   a  includes a main region  14   a  and a routing region  15   a  separately located at a side of the main region  14   a.  Besides, the accommodating space  100   a  is located in the main region  14   a,  and the shielding space  101   a  is located in the routing region  15   a.  More specially, the routing region  15   a  and the main region  14   a  are provided isolatedly for having an electricity controlling space of the electronic device  1   a.  In this way, the configuration is good for maintenance and keeps better electrical characteristics. 
     Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and improvements have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and improvements are intended to be embraced within the scope of the invention as defined in the appended claims.