Abstract:
A dust-proofing method is for use in an electronic device having a housing, a heat-generating component, and a dust-proofing mechanism. The housing includes an air vent. The dust-proofing mechanism includes a shielding plate for shielding or opening the air vent, and an actuating unit for driving movement of the shielding plate. The dust-proofing method includes: causing the actuating unit to drive movement of the shielding plate to open the air vent upon detecting that the temperature of the heat-generating component has risen to a first preset temperature; and causing the actuating unit to drive movement of the shielding plate to shield the air vent upon detecting that the temperature of the heat-generating component has dropped to a second preset temperature lower than the first preset temperature. Thus, dust accumulation in the electronic device can be effectively reduced, and heat dissipation efficiency can be enhanced.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority of Taiwanese Application No. 098102232, filed on Jan. 21, 2009. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates to a dust-proofing method for an electronic device and to the electronic device, more particularly to a dust-proofing method for an electronic device which controls opening and closing of an air vent in response to changes in the temperature of a heat-generating component, and to the electronic device. 
         [0004]    2. Description of the Related Art 
         [0005]    Since current notebook computers are designed to be compact in size and lightweight, how to ensure that a heat-dissipating module has a satisfactory heat-dissipating efficiency with respect to a central processing unit (CPU) under the constraint of limited space is an important issue. 
         [0006]    Many of the causes for poor heat dissipation are associated with accumulation of dust on impellers of the fan of the heat-dissipating module, or accumulation of dust on heat-dissipating fins of the heat-dissipating module. One way to alleviate the problem of dust accumulation is that, instead of arranging an air vent immediately below the fan of the heat-dissipating module, the air vent is provided at other positions of the housing of the notebook computer to introduce air into the housing. Although such a method can slow down the accumulation of dust, with the central processing unit operating under heavier and heavier loads, the working temperature of the central processing unit becomes higher and higher. Given that the air intake area provided by the air vent is fixed and that the amount of air intake hence cannot be increased to enhance heat dissipation efficiency, to devise a design that can effectively reduce dust accumulation and that can timely increase the amount of air intake with the rise in the working temperature of the central processing unit is the subject of improvement of this invention. 
       SUMMARY OF THE INVENTION 
       [0007]    Therefore, the primary object of the present invention is to provide a dust-proofing method for an electronic device, which can effectively reduce dust accumulation and enhance heat dissipation efficiency by controlling the opening or closing of an air vent of the electronic device. 
         [0008]    Another object of the present invention is to provide an electronic device capable of effectively reducing dust accumulation and enhancing heat dissipation efficiency by controlling the opening or closing of an air vent of the electronic device. 
         [0009]    The objects of the present invention and the solution to the problems associated with the aforementioned prior art are realized using the following technical means. The dust-proofing method according to the present invention is used in an electronic device including a housing, and a heat-generating component and a dust-proofing mechanism provided in the housing. The housing includes an air vent. The dust-proofing mechanism includes a shielding plate for shielding or opening the air vent, and an actuating unit for driving movement of the shielding plate. The dust-proofing method comprises: 
         [0010]    (A) causing the actuating unit to drive movement of the shielding plate to open the air vent upon detecting that the temperature of the heat-generating component has risen to a first preset temperature; and 
         [0011]    (B) causing the actuating unit to drive movement of the shielding plate to shield the air vent upon detecting that the temperature of the heat-generating component has dropped to a second preset temperature lower than the first preset temperature. 
         [0012]    In the aforementioned dust-proofing method, the heat-generating component is a central processing unit. The first preset temperature is 80° C. The second preset temperature is 65° C. The first and second preset temperatures may be adjusted depending on the kind of venue the electronic device is used and design requirements. 
         [0013]    The electronic device of the present invention includes a housing, a heat-generating component, and a dust-proofing mechanism. 
         [0014]    The housing includes a receiving space and an air vent in fluid communication with the receiving space. The heat-generating component is provided in the receiving space. The dust-proofing mechanism includes a temperature detecting element for detecting the temperature of the heat-generating component, a shielding plate for shielding or opening the air vent, and an actuating unit for driving the shielding plate to move relative to the housing. The actuating unit drives movement of the shielding plate to open the air vent when the temperature detecting element detects that the temperature of the heat-generating component has risen to a first preset temperature. The actuating unit drives movement of the shielding plate to shield the air vent when the temperature detecting element detects that the temperature of the heat-generating component has dropped to a second preset temperature lower than the first preset temperature. 
         [0015]    In the aforementioned electronic device, the dust-proofing mechanism further includes a controller connected electrically to the temperature detecting element for receiving temperature detect signals therefrom and for controlling operation of the actuating unit. 
         [0016]    In the aforementioned electronic device, the actuating unit includes a drive circuit, a motor, and a linkage connected to the shielding plate and the motor. The drive circuit drives the motor to operate to enable the motor to drive movement of the linkage so as to bring the shielding plate to move between an open position to open the air vent and a shielding position to shield the air vent. 
         [0017]    In the aforementioned electronic device, the motor has a stator, and a rotor rotatable relative to the stator and connected pivotally to the linkage. The rotor includes a ring-shaped magnet. The drive circuit supplies an electric current to the stator to enable the stator to generate a magnetic field so as to enable the magnet of the rotor to rotate relative to the stator by virtue of a magnetic force created by the magnetic field. 
         [0018]    In the aforementioned electronic device, the actuating unit further includes a position sensing element, which is controllable by the controller to sense positions of magnetic poles of the magnet so as to cause the drive circuit to supply an electric current to the stator. 
         [0019]    In the aforementioned electronic device, the housing further includes two elongated guide rails provided respectively at two opposite sides of the air vent and connected slidably to the shielding plate. 
         [0020]    In the aforementioned electronic device, the heat-generating component is a central processing unit. The first preset temperature is 80° C., and the second preset temperature is 65° C. 
         [0021]    In the dust-proofing method for the electronic device according to this invention, by virtue of the configuration of the dust-proofing mechanism, the shielding plate will move from the shielding position to the open position when the working temperature of the heat-generating component rises to the first preset temperature so as to increase the amount of air intake for enhancing heat dissipation efficiency, and will move from the open position to the shielding position when the temperature of the heat-generating component drops from the first preset temperature or a temperature above the first preset temperature to the second preset temperature, thereby preventing entry of dust into the receiving space through the air vent. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which: 
           [0023]      FIG. 1  is an exploded perspective view of a preferred embodiment of an electronic device according to the invention; 
           [0024]      FIG. 2  is a fragmentary perspective view of the electronic device of  FIG. 1 ; 
           [0025]      FIG. 3  is a fragmentary schematic view of the preferred embodiment of the electronic device according to the invention, illustrating a shielding plate at a shielding position; 
           [0026]      FIG. 4  is a schematic view of the preferred embodiment of the electronic device according to the invention, illustrating the arrangement relationship between a stator and a rotor of a motor when the shielding plate is at the shielding position; 
           [0027]      FIG. 5  is a block diagram to illustrate a dust-proofing mechanism of the preferred embodiment of the electronic device according to the invention; 
           [0028]      FIG. 6  is a flowchart to illustrate a preferred embodiment of a dust-proofing method according to the invention; 
           [0029]      FIG. 7  is a fragmentary schematic view of the preferred embodiment of the electronic device according to the invention, illustrating how the motor drives movement of a linkage and the shielding plate; 
           [0030]      FIG. 8  is a view similar to  FIG. 4 , illustrating how the rotor rotates relative to the stator; 
           [0031]      FIG. 9  is a fragmentary schematic view of the preferred embodiment of the electronic device according to the invention, illustrating the shielding plate at an open position; 
           [0032]      FIG. 10  is a schematic view of the preferred embodiment of the electronic device according to the invention, illustrating the arrangement relationship between the stator and the rotor of the motor when the shielding plate is at the open position; and 
           [0033]      FIG. 11  is a view similar to  FIG. 10 , illustrating how the rotor rotates relative to the stator. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0034]    Through a description of the preferred embodiment, the technical means employed by the present invention to achieve the intended objects and advantageous effects of the invention can be better appreciated. It is noted that the accompanying drawings are for illustration and reference only, and are not intended to limit the scope of protection sought for the present invention. 
         [0035]    The preferred embodiment of a dust-proofing method according to the present invention is for use in an electronic device  100  as shown in  FIGS. 1 and 2 . The electronic device  100  includes a housing  1 , a motherboard  2 , a heat-generating component  3 , a heat-dissipating module  4 , and a dust-proofing mechanism  5 . In this embodiment, the electronic device  100  is a notebook computer, and the heat-generating component  3  is a central processing unit disposed on the motherboard  2 . Certainly, the electronic device  100  may be a desktop computer or any other type of computer, and the heat-generating component  3  may be a chip or any other electronic component that will generate a large amount of heat during operation. 
         [0036]    The housing  1  includes a bottom plate  11 , a surrounding wall  12  connected to and surrounding the bottom plate  11 , and a receiving space  13  cooperatively defined by the bottom plate  11  and the surrounding wall  12 . The motherboard  2 , the heat-dissipating module  4 , and the dust-proofing mechanism  5  are provided in the receiving space  13 . The bottom plate  11  is provided with a plurality of air vents  111  in fluid communication with the receiving space  13 , and two elongated guide rails  112  located respectively at opposite left and right sides of the plurality of air vents  111 . The air vents  111  are located below a fan  41  of the heat-dissipating module  4 . Heat-dissipating fins  42  of the heat-dissipating module  4  are in abutment with the heat-generating component  3 . Thus, the outside air can be drawn into the housing  1  by the fan  41  of the heat-dissipating module through the air vents  111  to blow toward the heat-dissipating fins  42 , so as to dissipate the heat transferred to the heat-dissipating fins  42  by the heat-generating component  3  when the latter operates via air outlets  121  in the surrounding wall  12 . 
         [0037]    Referring to  FIGS. 2 ,  3 ,  4 , and  5 , the dust-proofing mechanism  5  includes a temperature detecting element  51 , a controller  52 , a shielding plate  53 , and an actuating unit  54 . The temperature detecting element  51  is provided on the motherboard  2  for detecting the temperature of the heat-generating component  3  (see  FIG. 1 ), and correspondingly generates different temperature detect signals in response to changes in the temperature of the heat-generating component  3  when the heat-generating component  3  operates. The controller  52  is an embedded controller connected electrically to the temperature detecting element  51  for receiving the temperature detect signals from, the temperature detecting element  51 . The shielding plate  53  is connected slidably to the two elongated guide rails  112 , and is driven by the actuating unit  54  to shield or open the air vents  111 . When the electronic device  100  is powered off, the shielding plate  53  is in a shielding position where it shields the air vents  111 , as shown in  FIG. 3 . The actuating unit  54  is controlled by the controller  52  to drive movement of the shielding plate  53 . The actuating unit  54  includes a motor  541 , a linkage  542 , a position sensing element  543 , and a drive circuit  544 . The motor  541  is provided on the motherboard  2 , and has a stator  545  and a rotor  546  rotatable relative to the stator  545 . The stator  545  includes two coils  547 ,  548  that are located at opposite sides thereof. The rotor  546  includes a rotating shaft  549 , and a ring-shaped magnet  550  surrounding the coils  547 ,  548  of the stator  545 . The linkage  542  has a first link portion  551  and a second link portion  552 . The first link portion  551  has one end pivoted to the rotating shaft  549  of the rotor  546 . The second link portion  552  has two ends pivoted respectively to the other end of the first link portion  551  and the shielding plate  53 , whereby rotation of the rotating shaft  549  of the motor  541  can drive movement of the linkage  542  and the shielding plate  53 . 
         [0038]    The position sensing element  543  is provided on the motherboard  2  for sensing positions of a north pole  553  and a south pole  554  of the magnet  550  of the rotor  546 . The position sensing element  543  transmits sensing signals to the drive circuit  544  to cause the drive circuit  544  to supply an electric current to the coils  547 ,  548  of the stator  545  so that the coils  547 ,  548  generate a magnetic field, whereby the magnet  550  of the rotor  546  is capable of rotation relative to the stator  545  by virtue of the magnetic force created by the magnetic field thus generated. 
         [0039]    The dust-proofing method for the electronic device  100  according to this invention will be described in detail hereinbelow with reference to  FIGS. 3 ,  4 ,  5 , and  6 .  FIG. 6  is a flowchart illustrating the dust-proofing method for the electronic device  100 . 
         [0040]    In step  61 , after the electronic device  100  is powered on, the temperature detecting element  51  detects the temperature of the heat-generating component  3 , and transmits a temperature detect signal to the controller  52 . When the temperature detecting element  51  detects that the temperature of the heat-generating component  3  has risen to a first preset temperature, which is, e.g., set to be 80° C. in this embodiment, the controller  52  will send a control voltage to the fan  41  of the heat-dissipating module  4  and the position sensing element  543  to cause the fan  41  to rotate at an increased speed and to drive the position sensing element  543  to sense the positions of the north pole  553  and the south pole  554  of the magnet  550  of the rotor  546 . The position sensing element  543  will transmit the sensing signals to the drive circuit  544  so that the drive circuit  544  can supply an electric current to the coils  547 ,  548  of the stator  545  depending on the positions of the north pole  553  and the south pole  554  of the magnet  550 , thereby enabling the coils  547 ,  548  to create a magnetic field which repels the magnet  550 . 
         [0041]    Referring to  FIGS. 3 ,  4 ,  7 , and  8 , after an electric current is supplied to the coils  547 ,  548  of the stator  545  by the drive circuit  544  (see  FIG. 5 ), the coil  547  (see  FIG. 4 ) will generate a south pole, whereas the coil  548  (see  FIG. 4 ) will generate a north pole. Under the principle that like poles repel and unlike poles attract, the magnet  550  of the rotor  546  will rotate relative to the stator  545  along a direction indicated by the arrow (I) (see  FIG. 8 ) as a result of the magnetic force thus generated so as to drive movement of the linkage  542  and the shielding plate  53 . When the north pole  553  and the south pole  554  of the magnet  550  of the rotor  546  have rotated 180 degrees, as shown in  FIG. 8 , and are respectively attracted to the coils  547 ,  548 , the shielding plate  53  moves along an extension direction of the elongated guide rails  112  from the shielding position where the shielding plate  53  shields the air vents  111 , as shown in  FIG. 3 , to the open position where the air vents  111  are opened, as shown in  FIG. 9 . Thus, the fan  41  of the heat-dissipating module  4  can not only draw in the outside air through air vents (not shown) arranged in other positions of the housing  1 , it can also draw in the outside air directly through the air vents  111  to blow toward the heat-dissipating fins  42  (see  FIG. 1 ), so that the heat transferred to the heat-dissipating fins  42  by the heat-generating component  3  can be dissipated through the air outlets  121 . 
         [0042]    Referring to  FIGS. 5 ,  6 ,  9 , and  10 , in step  62 , when the temperature detecting element  51  detects that the temperature of the heat-generating component  3  has dropped from the first preset temperature or a temperature above the first preset temperature to a second preset temperature (which is, e.g., set to 65°C. in this embodiment) lower than the first preset temperature, the controller  52  will send a control voltage to the fan  41  of the heat-dissipating module  4  and the position sensing element  543  to cause the fan  41  to rotate at a reduced speed, and to simultaneously drive the position sensing element  543  to sense the positions of the north pole  553  and the south pole  554  of the magnet  550  of the rotor  546  and to transmit the sensing signals to the drive circuit  544 , so that the drive circuit  544  can supply an electric current to the coils  547 ,  548  of the stator  545  depending on the positions of the north pole  553  and the south pole  554  of the magnet  550 , thereby enabling the coils  547 ,  548  to generate a magnetic field which repels the magnet  550 . The coil  547  (see  FIG. 10 ) will generate a north pole, whereas the coil  548  (see  FIG. 10 ) will generate a south pole, so that the rotor  546  is brought to rotate relative to the stator  545  along a direction indicated by arrow (II) (see  FIG. 11 ) by the magnetic force thus generated so as to drive movement of the linkage  542  and the shielding plate  53 . When the north pole  553  and the south pole  554  of the magnet  550  of the rotor  546  have rotated 180 degrees, as shown in  FIG. 11 , and are respectively attracted to the coils  548 ,  547 , the shielding plate  53  moves along the extension direction of the elongated guide rails  112  from the open position shown in  FIG. 9  to the shielding position shown in  FIG. 3 . Thus, entry of dust into the receiving space  13  through the air vents  111  can be prevented. 
         [0043]    It is particularly noted that, except in circumstances where the user uses the electronic device  100  to play games or execute simulation analysis software, or the electronic device  100  is used in a hot environment so that the temperature of the heat-generating component rises above the first preset temperature due to increased workload of the heat-generating component  3  or environmental temperature influences, under normal use conditions, the working temperature of the heat-generating component  3  is generally below the first preset temperature. Therefore, the shielding plate  53  is normally disposed at the shielding position to shield the air vents  111 , thereby effectively reducing the amount of dust entering through the air vents  111  and accumulating on the fan  41  and the heat-dissipating fins  42  of the heat-dissipating module  4 . The actuating unit  54  will drive the shielding plate  53  to move to the open position to increase the amount of air intake for enhancing the efficiency of dissipating the heat of the heat-generating component  3  only when the temperature of the heat-generating component  3  has risen to the first preset temperature. The first and second preset temperatures may be adjusted depending on the kind of venue the electronic device  100  is used and design requirements, and should not be limited to the temperatures disclosed in this embodiment. 
         [0044]    In addition, although the operation of the dust-proofing mechanism  5  is illustrated to be in relation to changes in the temperature of the heat-generating component  3  from a power-off state to a state in which the temperature of the heat-generating component  3  has risen to the first preset temperature and in relation to the drop in temperature from the first preset temperature or a temperature above the first preset temperature to the second preset temperature, the working temperature of the heat-generating component  3  will fluctuate during actual operation. Therefore, the shielding plate  53  of the dust-proofing mechanism  5  will continuously move between the shielding position and the open position. Furthermore, if the temperature of the heat-generating component  3  is maintained at a temperature below the first preset temperature after powering on the electronic device  100 , the shielding plate  53  will be maintained at the shielding position. The shielding plate  53  will move to the open position only when the temperature of the heat-generating component  3  rises to the first preset temperature. 
         [0045]    In sum, in the dust-proofing method for the electronic device  100  according to this invention, by virtue of the configuration of the dust-proofing mechanism  5 , the shielding plate  53  will move from the shielding position to the open position when the working temperature of the heat-generating component rises to the first preset temperature so as to increase the amount of air intake for enhancing heat dissipation efficiency, and will move. from the open position to the shielding position when the temperature of the heat-generating component  3  drops from the first preset temperature or a temperature above the first preset temperature to the second preset temperature, thereby preventing entry of dust into the receiving space  13  through the air vents  111 . 
         [0046]    While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.