Patent Publication Number: US-2011063801-A1

Title: Electronic device with a heat insulating structure

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an electronic device, and more particularly, to an electronic device with a heat insulating structure capable of preventing heat from directly transmitting toward an enclosure. 
     2. Description of the Prior Art 
     With the advanced technology, a consumer electronic device includes several heat sources, such as a CPU (Central Processing Unit or SoC (System on Chip) or Power IC or a chip. Heat generated by the heat sources affects operational stability of the electronic device easily. Therefore, kinds of components are designed for dissipating the heat generated by the heat sources, such as a heat sink or a fan. Most enclosures of the electronic device can be made of plastic material. The plastic enclosure has low heat dissipating efficiency so that the heat generated by the heat sources and transmitting toward the enclosure directly warms the enclosure up violently. If temperature of the enclosure exceeds tolerance that a user&#39;s skin can bear, the user is hard to hold the electronic device, even being hurt by the heat. Thus, solution of the enclosure with high temperature is an important issue in the mechanical design industry. 
     SUMMARY OF THE INVENTION 
     The present invention provides an electronic device with a heat insulating structure for solving above drawbacks. 
     According to the claimed invention, an electronic device includes a circuit board, and a heat insulating structure. The heat insulating structure includes a heat source disposed on the circuit board, an enclosure for covering the circuit board and the heat source, and a heat insulating plate disposed or glued on a side of the enclosure facing to the heat source for preventing heat generated by the heat source from directly transmitting toward the enclosure, and a space being formed between the heat insulating plate and the enclosure. 
     According to the claimed invention, the heat insulating structure further includes a thermal conductive layer disposed on a side of the heat insulating plate. 
     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 
         FIG. 1  is an exploded diagram of an electronic device according to a first embodiment of the present invention. 
         FIG. 2  is a bottom view of an enclosure and a heat insulating plate according to the first embodiment of the present invention. 
         FIG. 3  is a lateral view of the enclosure and the heat insulating plate according to the first embodiment of the present invention. 
         FIG. 4  is a diagram of the electronic device according to a second embodiment of the present invention. 
         FIG. 5  is a diagram of the electronic device according to a third embodiment of the present invention. 
         FIG. 6  is a diagram of the electronic device according to a fourth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. The components of the present invention can be positioned in a number of different orientations. As such, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “facing,” “faces” and variations thereof herein are used broadly and encompass direct and indirect facing, and “adjacent to” and variations thereof herein are used broadly and encompass directly and indirectly “adjacent to”. Therefore, the description of “A” component facing “B” component herein may contain the situations that “A” component facing “B” component directly or one or more additional components is between “A” component and “B” component. Also, the description of “A” component “adjacent to” “B” component herein may contain the situations that “A” component is directly “adjacent to” “B” component or one or more additional components is between “A” component and “B” component. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive. 
     Please refer to  FIG. 1 .  FIG. 1  is an exploded diagram of an electronic device  10  according to a first embodiment of the present invention. The electronic device  10  includes a circuit board  12  and a heat insulating structure  14 . The heat insulating structure  14  includes a heat source  16  disposed on the circuit board  12 , an enclosure  18  for covering the circuit board  12  and the heat source  16 , and a heat insulating plate  20  disposed on a side of the enclosure  18  facing to the heat source  16  for preventing heat generated by the heat source  16  from directly transmitting toward the enclosure  18 . Please refer to  FIG. 1  to  FIG. 3 .  FIG. 2  is a bottom view of the enclosure  18  and the heat insulating plate  20  according to the first embodiment of the present invention.  FIG. 3  is a lateral view of the enclosure  18  and the heat insulating plate  20  according to the first embodiment of the present invention. A space is formed between the heat insulating plate  20  and the enclosure  18 . The heat insulating plate  20  can be disposed on the enclosure  18  in a heat melt manner. For example, the enclosure  18  can include at least one heat stake  181  so that the heat insulating plate  20  can be staked on the heat stake  181  by a heat melt manner. The heat insulating plate  20  also can be glued on the enclosure  18 . The heat insulating plate  20  can further be disposed on the enclosure  18  by the heat melt manner with wall structure, circular structure, or the combination of the wall structure, circular structure, and the heat stake  181 . The heat insulating plate  20  can further be integrated with the enclosure  18  monolithically. In addition, at least one hole  183  is formed on the enclosure  18  for dissipating the heat generated by the heat source  16  effectively and at least one rib  185  can be formed on the enclosure  18  for strengthening loading bearing on the enclosure  18 . The hole  183  can be formed adjacent to the rib  185 , respectively. Assembly of the heat insulating plate  20  on the enclosure  18  is not limited to the above-mentioned embodiment and depends on design demand. The heat insulating structure  14  can further include a heat dissipating component  22  disposed on the heat source  16  for dissipating the heat generated by the heat source  16 . For example, the heat dissipating component  22  can be a heat sink, a thermal pad, or any other material which can dissipate heat. In order to prevent the heat generated by the heat source  16  from directly transmitting toward the enclosure  18 , dimensions of the heat insulating plate  20  is larger than or equal to dimensions of the heat source  16  or the heat dissipating component  22  in a preferred embodiment. Corresponding dimensions of the heat insulating plate  20 , the heat source  18 , and the heat dissipating component  22  are not limited to the above-mentioned method, and it depends on design demand. In addition, the heat insulating plate  20  can be made of plastic material, such as Mylar material, so as to insulate the heat effectively. The heat insulating plate  20  can further be the thermal pad. The heat insulating plate  20  is not limited to the above-mentioned material and depends on design demand. 
     Please refer to  FIG. 4 .  FIG. 4  is a diagram of the electronic device  10  according to a second embodiment of the present invention. In above embodiments, components have the same numerals as the above-mentioned embodiment have the same structures and functions and the detail description is omitted herein for simplicity. As shown in  FIG. 4 , the heat insulating structure  14  can further include a thermal conductive layer  24  disposed on a side of the heat insulating plate  20  facing to the heat source  16  for improving heat dissipating efficiency of the heat insulating plate  20 . The thermal conductive layer  24  can be made of metal material or graphite material having preferred heat conductivity, such as copper, alumni and so on. Shape of the thermal conductive layer  24  is designed according to mechanical demand, such as a membrane or a mesh, and corresponding dimensions of the thermal conductive layer  24  and the heat insulating  20  are designed according to the actual demand. In addition, part of the enclosure  18  can be an upper housing of the electronic device  10 . 
     Please refer to  FIG. 5 .  FIG. 5  is a diagram of the electronic device  10  according to a third embodiment of the present invention. The heat insulating structure  14  can further include the thermal conductive layer  24  disposed on a side of the heat insulating plate  20  facing to the enclosure  18  for improving the heat dissipating efficiency of the heat insulating plate  20 . Because pins  161  of the heat source  16  (not be shown in  FIG. 5 ) mounted on the circuit board  12  might pierce through a side of the circuit board  12  opposite to the other side of the circuit board  12  whereon the heat source  16  disposed, the heat insulating plate  20  can be further utilized for insulating electrical connection of the circuit board  12  and the thermal conductive layer  24 . The thermal conductive layer  24  can be made of metal material having preferred heat conductivity, such as copper, alumni and so on. Shape of the thermal conductive layer  24  is designed according to mechanical demand, such as a membrane or a mesh, and the corresponding dimensions of the thermal conductive layer  24  and the heat insulating  20  are designed according to the actual demand. In addition, part of the enclosure  18  can be a lower housing of the electronic device  10 . 
     Please refer to  FIG. 6 .  FIG. 6  is a diagram of the electronic device  10  according to a fourth embodiment of the present invention. The heat insulating structure  14  including the thermal conductive layer  24  disposed on the side of the heat insulating plate  20  facing to the circuit board  12  can further include an insulating layer  26  disposed between the thermal conductive layer  24  and the circuit board  12 . The insulating layer  26  can insulate electrical connection of the circuit board  12  and the thermal conductive layer  24  so that the thermal conductive layer  24  can be disposed between the heat insulating plate  20  and the circuit board  12 . In this embodiment, elements have the same numerals as the third embodiment have the same structures and functions, and detail description is omitted herein for simplicity. 
     In conclusion, design of the heat insulating plate  20  disposed between the enclosure  18  and the heat source  16  can prevent the heat generated by the heat source  16  from transmitting toward the enclosure  18  effectively. The heat insulating plate  20  can be disposed on the enclosure in the heat melt manner, such as being staked on the heat stake  181 , so as to economize manufacturing cost and labor hours. In addition, because the heat generated by the heat source  16  can be transmitted by conduction, radiation, and convection, the space formed between the heat insulating plate  20  and the enclosure  18  can be for preventing heat dissipated from the heat insulating plate  20  from conducting toward the enclosure  18  directly. The heat insulating plate  20  also can be directly connected to the enclosure  18  without intervening space. The heat insulating plate  20  can be utilized for altering upward heat current generated by the heat source  16  to dissipate laterally so as to dissipate the heat current via neighboring holes  183  on the enclosure  18  uniformly. The heat insulating plate  20  can be made of heat insulating material having low heat dissipating efficiency. The heat insulating plate  20  can further be made of thermal conductive material, such as graphite material. The heat insulating structure  14  can further include the thermal conductive layer  24  disposed on the side of the heat insulating plate  20  facing to the heat source  16  for dissipating the heat transmitting toward the heat insulating plate  20  and the enclosure  18  when the heat insulating plate  20  is disposed on the upper housing of the electronic device  10  as shown in  FIG. 4 . The thermal conductive layer  24  is for dissipating the heat transmitting from the heat source  16  first, so as to decrease the heat transmitting toward the heat insulating plate  20  and the enclosure  18 . For this reason, the heat generated by the heat source  16  is not transmitted toward the enclosure  18  directly by setting the heat insulating plate  20  and the thermal conductive layer  24  so as to cool down temperature of the enclosure  18 . 
     Because an interval between the circuit board  12  and the lower housing of the electronic device  10  is small due to limitation of mechanical arrangement, the heat insulating structure  14  can further include the thermal conductive layer  24  disposed by the side of the heat insulating plate  20  facing to the enclosure  18  when the heat insulating plate  20  is disposed or glued on the lower housing of the electronic device  10  as shown in  FIG. 5 . For preventing the pins of the heat source  16  piercing through the side of the circuit board  12  from contacting with the thermal conductive layer  24 , the thermal conductive layer  24  can be disposed by the side of the heat insulating plate  20  facing to the enclosure  18  so as to avoid a short circuit. The thermal conductive layer  24  is for dissipating the heat transmitting from the heat insulating plate  20 , and disposition of the heat insulating plate  20  can be for insulating electrical connection of the circuit board  12  and the thermal conductive layer  24 . The heat generated by the heat source  16  is not transmitted toward the enclosure  18  directly by setting the heat insulating plate  20  and the thermal conductive layer  24  so as to cool down the temperature of the enclosure  18 . 
     Comparing to the prior art, the present invention provides the heat insulating structure with enhanced heat insulating efficiency. The heat insulating plate can insulate the heat generated by the heat source transmitting toward the enclosure so as to cool down the temperature of the enclosure, and the thermal conductive layer can further assist dissipation of the heat transmitting from the heat insulating plate effectively. Therefore, the present invention provides a new design for preventing the enclosure of the electronic device from heating and has advantages of low cost and convenient assembly. 
     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.