Patent Abstract:
In an electronic appliance, a base is thermally fused by a heat generating component. On the base, a heat dissipating fin group including heat dissipating fins each extending in a Y direction is arranged in spaced relation in an X direction. An exhaust fan and a partition between which the heat dissipating fin group is sandwiched in the Y direction are arranged so as to be faced with each other. The edge portion group of the heat dissipating fin group on the side of the partition is farthest from the wall surface at least one outermost position in the X direction and closest from the wall surface at a specific position different from the one outermost position, and is farther from the wall surface between the specific position and the one outermost position as the one outermost position is approached.

Full Description:
CROSS REFERENCE OF RELATED APPLICATION 
       [0001]    The disclosure of Japanese Patent Application No. 2006-302508 is incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to an electronic appliance. More specifically, the present invention relates to an electronic appliance having a heat dissipating mechanism for dissipating a heat in a heat generating component. 
         [0004]    2. Description of the Related Art 
         [0005]    As a conventional structure of such a kind, there is one disclosed in Japanese Patent Laying-open No. 1985-22398 (Patent Document 1). Acceding to Patent Document 1, heat dissipating fins are secured to a base to be attached to a heat generating component to allow air to flow through one end of the heat dissipating fin to the other. The heat dissipating fin group becomes higher from the entrance side from where air is taken in to the exit side from where the air is exhausted. Since the temperature of the air flowing along the heat dissipating fins is high as the exit is approached, the heat dissipating fin is formed so as to be higher to the exit side, capable of obtaining high heat dissipating efficiency. 
         [0006]    Furthermore, there is one disclosed in Japanese Patent Laying-open No. 2004-186702 (Patent Document 2). According to Patent Document 2, a plurality of heat dissipating fins are arranged in series with each other on a base to be attached to a heat generating component. A wall surface is provided so as to face the base in such a manner that the plurality of heat dissipating fins are sandwiched therebetween, and an air duct is formed between the wall surface and the base. An exhaust fan is provided on the exit side of the air duct, and the air duct between the wall surface and the base becomes narrower as the exit side is approached. Thus, by widening the entrance side of the air duct, air being free from the heat dissipation by the heat dissipating fins at the entrance side is supplied with the heat dissipating fins at the exit side, capable of realizing a uniform cooling performance of each heat dissipating fin. 
         [0007]    By the way, in electronic appliances like a game machine, etc., for the necessity of miniaturization and an optimal location, some members (wall member, component, or the like) may be arranged relatively near heat dissipating fins and heat generating components. In such a case, there is a problem of realizing a structure in view of the heat by the heat generating components. 
         [0008]    For example, there is a case that some wall member (wall surface, component with wall part, or the like) are desired to be arranged on the entrance side of the air of the heat dissipating fin. In this case, an air intake channel to the heat dissipating fin may relatively be narrow due to the above-described wall member, and in such a case also, there is a problem of heightening the heat dissipating efficiency of the heat generating component. 
         [0009]    Furthermore, there is a case that other components such as a disk drive, or the like is desired to be placed relatively near heat generating components, for example. In this case, there is a problem of preventing an adverse effect of the heat from the heat generating component on the other components. 
         [0010]    In Patent Documents 1 and 2, there is no disclosure about means for solving the above described problems. 
       SUMMARY OF THE INVENTION 
       [0011]    Therefore, it is a primary object of the present invention to provide a novel electronic appliance. 
         [0012]    Another object of the present invention is to provide a structure taking heat of a heat generating component into consideration while responding to the necessity of miniaturization and an optimal location. 
         [0013]    An electronic appliance according to a first aspect of the present invention comprises: a heat generating component; a base provided in a position being opposite to the heat generating component; a heat dissipating fin group which includes a plurality of fins arranged on the base in a manner that each of heat dissipating fins extends in a first direction (Y) and is arranged in spaced relation in a second direction (X) crossing the first direction, edge portions of the plurality of heat dissipating fins constituting edge portion groups on the side of the wall surface and on the side of the exhaust fan; and a exhaust fan and a wall surface being opposite to each other with which the heat dissipating fin group is sandwiched in the first direction. The edge portion group (T 2 ) of the heat dissipating fin group on the side of the wall surface is farthest from the wall surface at least one outermost position in the second direction and closest from the wall surface at a specific position different from the one outermost position in the second direction, and is farther from the wall surface between the specific position and the one outermost position as the one outermost position is approached. 
         [0014]    In the first aspect, on the base being opposite to the heat generating component, a heat dissipating fin group including heat dissipating fins each of which extends in a first direction is arranged in spaced relation in a second direction. It should be noted that “the base being opposite to the heat generating component” includes a structure when a part of the heat generating component and a part of the base is being opposite. An exhaust fan and a wall surface are opposite to each other with which the heat dissipating fin group is sandwiched in the first direction. 
         [0015]    The edge portion group of the heat dissipating fin group on the side of the wall surface is farthest from the wall surface at least one outermost position in the second direction and closest from the wall surface at a specific position different from the one outermost position in the second direction, and is farther from the wall surface between the specific position and the one outermost position as the one outermost position is approached. 
         [0016]    According to the first aspect, one or two intake channels (QL, QR) is formed by the edge portion group of the heat dissipating fin group on the side of the wall surface and the wall surface. The (these) intake channel can take a large amount of outside air because of having a large opening, and can uniformly supply the taken air to the heat dissipating fin group because the width thereof is narrower at the depth. In such a case, the amount of air passing through the intake channel is gradually less, and therefore, the depth of the intake channel does not become a bottle neck. Thus, it is possible to obtain a high heat dissipating efficiency with respect to the heat dissipating component arranged near the wall surface. 
         [0017]    As a result, it is possible to heighten heat dissipating efficiency of the heat generating component while responding to the necessity of miniaturization and an optimal location. 
         [0018]    An electronic appliance according to a second aspect is dependent on the first aspect, and the edge portion group on the side of the wall surface is the farthest from the wall surface at both of outermost positions in the second direction, and the closest from the wall surface at an innermost position in the second direction. 
         [0019]    In the second aspect, two intake channels having the same size are formed. 
         [0020]    According to the second aspect, a total area of the opening is large, a large amount of air can be supplied with the heat dissipating fins, capable of obtaining a more heat dissipating efficiency. 
         [0021]    An electronic appliance according to a third aspect is dependent on the second aspect, the edge portion group on the side of the wall surface is farthest from the wall surface at one outermost position in the second direction, and closest from the wall surface at the other outermost position in the second direction. 
         [0022]    In the third aspect, one intake channel having a gentle inclination (that is, less difference between each of the edge portions on the side of wall surface) is formed. 
         [0023]    According to the third aspect, a less ventilating resistance of the intake channel allows admission of a large amount of air, capable of obtaining a high heat dissipating efficiency. 
         [0024]    An electronic appliance according to a fourth aspect is dependent on the second aspect, and the exhaust fan is placed at a position being opposite to the innermost position of the heat dissipating fin group in the second direction. 
         [0025]    According to the fourth aspect, it is possible to suck out air from the heat dissipating fin group, capable of obtaining a more heat dissipating efficiency. 
         [0026]    An electronic appliance according to a fifth aspect is dependent on the first to the fourth aspects, and the edge portion group of the heat dissipating fin group on the side of the exhaust fan (T 1 ) is placed at equal distances from the wall surface. 
         [0027]    In the fifth aspect, a heat dissipating fin being placed at least one outermost position, and having an edge portion farthest from the wall surface becomes shortest while the heat dissipating fin group becomes gradually longer to the depth from the above-described outermost position, and becomes the longest at the heat dissipating fin having the edge portion being the closest from the wall surface. 
         [0028]    Thus, it is structured that at the above-described outermost position, air can be easily taken in the heat dissipating fin group while the heat dissipating fin group is gradually longer to the depth from the above-described outermost position, and therefore, it is possible to efficiently dissipate heat by the heat dissipating fin group. As a result, it is possible to heighten heat dissipating efficiency of the heat generating component. 
         [0029]    An electronic appliance according to a sixth aspect is dependent on the first aspect, and further comprises other component and a housing. The wall surface is a face of a partition for separating the heat dissipating fin group from the other component, and the housing houses the heat generating component, the base, the heat dissipating fin group, the exhaust fan, the partition, and the other component. 
         [0030]    In the sixth aspect, the heat generating component, the base, the heat dissipating fin group, the exhaust fan, the partition, and other component are housed in the housing. The heat dissipating fin group is separated from the other component by the partition. 
         [0031]    According to the sixth aspect, it is possible to prevent an adverse effect of the heat from the heat generating component on the other components. 
         [0032]    An electronic appliance according to a seventh aspect is dependent on the sixth aspect, and the heat dissipating fin group is arranged only at a part of an area on the base, and at least a part of the other component is arranged on an area on which the heat dissipating fin group is not arranged on the base. 
         [0033]    In the seventh aspect, there is an area where the heat dissipating fin group is not arranged on the base, and at least a part of the other component is arranged on the area. 
         [0034]    According to the seventh aspect, it is possible to realize a space saving while preventing the heat of the heat dissipating component from being directly transmitted to the other component. 
         [0035]    An electronic appliance according to an eighth aspect is dependent on the seventh aspect, and further comprises an exhaust hole and an intake hole both of which are provided to the housing, the exhaust hole is placed at a position being opposite to the heat dissipating fin group via the exhaust fan, and the intake hole is placed at a position being opposite to an opening of an intake channel (QL, QR) formed by the edge portion group on the side of the wall surface of the heat dissipating fin group and the wall surface. 
         [0036]    In the eighth aspect, air taken out by the exhaust fan from the heat dissipating fin group is exhausted to the outside of the housing from the exhaust hole. As a result, an atmospheric pressure within the housing is reduced to allow outside air to be taken in the housing through the intake hole. The taken outside air is supplied to the heat dissipating fin group through the intake channel. 
         [0037]    According to the eighth aspect, the exhaust hole is placed at a position being opposite to the heat dissipating fin group via the exhaust fan, and the intake hole is placed at a position being opposite to an opening of an intake channel, capable of realizing smooth air intake and exhaust, and heighten heat-dissipating efficiency. 
         [0038]    An electronic appliance according to a ninth aspect comprises: a heat generating component; a base connected by heat to the heat generating component; a heat dissipating fin group arranged on the base; and other component. The heat dissipating fin group is arranged at only a part of an area on the base, and at least a part of the other component is arranged at an area where the heat dissipating fin group does not exist on the base. 
         [0039]    In the ninth aspect, the heat dissipating fin group is arranged on a base provided in a position being opposite to the heat generating component. There is an area on the base where the heat dissipating fin group is not arranged, and at least a part of the other component is arranged on the area. 
         [0040]    According to the ninth aspect, it is possible to prevent an adverse effect of the heat from the heat generating component on the other components while responding to the necessity of miniaturization and an optimal location. 
         [0041]    According to the present invention, it is possible to realize a structure in view of the heat from the heat generating component while responding to the necessity of miniaturization and an optimal location. 
         [0042]    The above described objects and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0043]      FIG. 1  is a perspective view of one embodiment of the present invention as seen from a front above; 
           [0044]      FIG. 2  is a perspective view of  FIG. 1  embodiment as seen from rear above; 
           [0045]      FIG. 3  is a perspective view of  FIG. 1  embodiment as seen from front below; 
           [0046]      FIG. 4  is an illustrative view showing a hidden part by a cover of a right side surface in  FIG. 1  embodiment; 
           [0047]      FIG. 5  is an illustrative view showing a part of an assembly process of  FIG. 1  embodiment; 
           [0048]      FIG. 6  is a perspective view showing a result of  FIG. 5  process (before the completion of the shield); 
           [0049]      FIG. 7  is an illustrative view showing a process continued from the  FIG. 5  process; 
           [0050]      FIG. 8  is a perspective view showing a result of the  FIG. 7  process (after completion of the shield); 
           [0051]      FIG. 9  is an illustrative view showing a state in which a drive unit, a partition, and an exhaust fan are further mounted after the  FIG. 7  process; 
           [0052]      FIG. 10  (A) is a top view showing a structure of a heat dissipating member applied to  FIG. 1  embodiment; 
           [0053]      FIG. 10  (B) is a side view showing a structure of the heat dissipating member; 
           [0054]      FIG. 10  (C) is a front view showing a structure of the heat dissipating member; 
           [0055]    FIG.  11 (A)-(C) are illustrative views showing a part of a manufacturing process of the heat dissipating member applied to  FIG. 1  embodiment; 
           [0056]      FIG. 12  is an illustrative view showing a flow of air in the heat dissipating member of  FIG. 1  embodiment; 
           [0057]      FIG. 13  is an illustrative view showing a flow of air in a heat dissipating member of another embodiment; 
           [0058]      FIG. 14  (A) is a top view showing the heat dissipating member of another embodiment; 
           [0059]      FIG. 14  (B) is a top view showing a heat dissipating member of the other embodiment; 
           [0060]      FIG. 14  (C) is a top view showing a heat dissipating member of a further embodiment; 
           [0061]      FIG. 15  is a top view showing a heat dissipating member of another embodiment; 
           [0062]      FIG. 16  is a top view showing a heat dissipating member of the other embodiment; and 
           [0063]      FIG. 17  is a top view showing a heat dissipating member of a further embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0064]    An appearance of a game apparatus  10  of one embodiment of the present invention is shown in  FIG. 1-FIG .  3 .  FIG. 1  is a perspective view of a game apparatus  10  as seen from above front,  FIG. 2  is a perspective view of the game apparatus  10  as seen from above back, and  FIG. 3  is a perspective view of the game apparatus  10  as seen from front below. 
         [0065]    As shown in  FIG. 1-FIG .  3 , the game apparatus  10  includes a substantially rectangular housing  12 . On a front surface  12   f  of the housing  12 , disk slot  14   a , a SD card slot cover  14   b , a power button  16   a , a reset button  16   b , a disk eject button  16   c , etc. are formed. 
         [0066]    On a right side surface  12 R of the housing  12 , a rubber foot  22 , an intake hole  24 , etc. are formed. On a back surface  12   b , a USB connector  26 , an exhaust hole  28 , a peripheral connector  30 , an AV connector  32 , a DC connector  34 , etc. are formed. On a bottom surface  12   u , a rubber foot  15 , an intake hole  25 , etc are formed. On a left side surface  12 L, an openable closeable covers  18   a  and  18   b  are formed. 
         [0067]      FIG. 4  shows a part hidden under the covers  18   a  and  18   b  of the left side surface  12 L. Referring to  FIG. 4 , the left side surface  12 L, a connector  20   a  for various controllers (not illustrated), a memory card slot  20   b , an intake hole  27 , are provided. 
         [0068]      FIG. 5  shows a part of an assembly process of the game apparatus  10 , and  FIG. 6  shows a result of the  FIG. 5  process. Referring to  FIG. 5  and  FIG. 6 , the housing  12  constructed as described above includes an electronic component like a CPU  38 , a GPU  40 , etc. and a substrate  36  mounted with the above-described connectors ( 20   a ,  20   b ,  30 ,  32  and  34 ). The substrate  36  is secured with a bottom  46  (corresponding to the bottom surface  12   u  of the housing  12 ) via a metal lower shield member  44 B. 
         [0069]    Each of the CPU  38  and the GPU  40  being an exothermic electronic component has roughly the same thickness, and arranged at the back and the center of the substrate  36 . Then, on a top surface of the CPU  38  and GPU  40 , a metal (aluminum, for example) heat dissipating member  48  is arranged. The heat dissipating member  48  has a plurality of heat dissipating fins  48   a  and a base  48   b  for supporting these. The base  48   b  takes a shape of rectangular, and has no more size than permit it to exactly cover the CPU  38  and GPU  40 . At each of the four corners of the base  48   b , a downward protrusion  48   c  taking a shape of cylinder, and a tapped hole  48   d  penetrating the base itself and the protrusion  48   c  are formed. The height of the protrusion  48   c  is slightly above the thicknesses of the CPU  38  and the GPU  40 . That is, the protrusion  48   c  is a leg for supporting the heat dissipating member  48  at a top surface position of the CPU  38  and the GPU  40 . 
         [0070]    Here, a structure of the heat dissipating member  48  is described in detail. The plurality of heat dissipating fins  48   a  are arranged at roughly fixed intervals in parallel with a short side of the base  48   b  as shown in  FIG. 10  (A). It should be noted that at only the interval between the two heat dissipating fins sandwiching the tapped hole  48   d , a wider interval is ensured for attaching a screw  54 . 
         [0071]    An edge: portion group T 1  on one side (upper side) of the plurality of heat dissipating fins  48   a  is arranged along a long side (top) L 1  of the base  48   b . With respect to the other long side (lower side) of the base  48   b , an edge portion group T 2  on the other side (lower side) of the plurality of heat dissipating fins  48   a  is arranged along a V-shaped line (C 1 ) such that the center thereof is closest, and the right and left thereof is the farthest. Out of the lower edge portion group T 2 , one along the line of the left side of the V-shaped letter is called a lower left edge portion group T 21 , and one along the line of the right side of the V-shaped letter is called a lower right edge portion group T 2   r.    
         [0072]    Thus, as shown in  FIG. 10  (B), it is possible to look through the entire lower right edge portion group T 2   r  (or the lower left edge portion group T 2   l ) of the heat dissipating member  48  from the left side surface (or right side surface). Furthermore, the plurality of heat dissipating fins  48   a  have the same height as one another as shown in  FIG. 10(C) . It should be noted that the heights of the plurality of heat dissipating fins  48   a  may be differentiated from one another, or the height of a single sheet of heat dissipating fin may be changed depending on the positions. 
         [0073]    Such a heat dissipating member  48  is manufactured in a following process. First, an original member  48 A (see  FIG. 11  (A)) having a base  48 Ab and a plurality of heat dissipating fins  48 Aa each having the same length as that of the base  48 Ab is molded by extrusion (not illustrated). Next, the original member  48 A on which the extrusion molding has been performed is subjected to a press work like cutting away a part of each of the plurality of heat dissipating fins  48 Aa with a press block (B 1  and B 2 ). 
         [0074]    In the press work, first, as shown in  FIG. 11  (A), the support member B 2  is inserted from the left between the first heat dissipating fin F 1  and the second heat dissipating fin F 2 , and the edge of the cutter member B 1  is placed at the left end of the V-shape line C 1 , and whereby, the heat dissipating fin F 1  is cut away by both of the members B 1  and B 2 . 
         [0075]    Next, as shown in  FIG. 11  (B), the support member B 2  is inserted from the left between the second heat dissipating fin F 2  and the third heat dissipating fin F 3 , and the cutter member B 1  is moved to the position of the heat dissipating fin F 2  along the V-shape line C 1 , and whereby, the heat dissipating fin F 2  is cut away by both of the members B 1  and B 2 . At this time, the cut-away position of the heat dissipating fin F 2  is lower than that of the heat dissipating fin F 1 , and therefore, the heat dissipating fin F 1  after the cut-away is never brought into contact with the cutter member B 1 . 
         [0076]    Later, heat dissipating fins F 3 , F 4  . . . are sequentially cut away along the V-shape line C 1  in the similar manner. After completion of cut-away of the central heat dissipating fin F 5 , as shown in  FIG. 11  (C), the direction of the cutter member B 1  is reversed to sequentially cut away the end of heat dissipating fins F 9 -F 6  along the V-shape line C 1  from the right at this time. The plurality of heat dissipating fins  48 Aa of the original member  48 A thus molded by extrusion is cut away along the V-shape line C 1 , which allows utilization of an extrusion with more simply shape than in a case that a die casting molding is directly performed on the heat dissipating member  48 , capable of reducing a manufacturing cost. 
         [0077]    Additionally, as described above, the heat dissipating fins F 1 -F 5  are cut away from the left, and then the heat dissipating fins F 9 -F 6  are cut away from the right. Alternatively, cuttings are simultaneously made from the left and from the right. That is, the F 1  and F 9  are first cut away, the F 2  and F 8  are cut away next, the F 3  and F 7  are then cut away, the F 4  and F 6  are succeedingly cut away, and the F 5  is finally cut away. Thus, it is possible to shorten a manufacturing time. 
         [0078]    As schematically shown in  FIG. 5 , a thermal conduction sheet  50  is inserted between the heat dissipating member  48 , and the CPU  38  and GPU  40 . The thermal conduction sheet  50  is made of material high in flexibility and thermal conductivity (silicone, or the like), having the top surface thereof be closely brought into contact with the bottom surface of the heat dissipating member  48 , and the bottom surface thereof be closely brought into contact with the top surface of the CPU  38  and the GPU  40 . The heat of the CPU  38  and the GPU  40  is efficiently transmitted to the heat dissipating member  48  through the thermal conduction sheet  50 , and emitted from the heat dissipating member  48 . It should be noted that a heat conducting grease like silicone grease may be utilized in place of or in combination with the thermal conduction sheet  50 . 
         [0079]    The substrate  36  is formed with four through holes  36   a  respectively corresponding to four tapped holes  48   d  of the heat dissipating member  48 . A lower shield member  44 B is formed with four tapped holes  44 Ba, and the bottom  46  is formed with four bearings  46   a . Also, four ferrite rings  52  are arranged between the heat dissipating member  48  and the substrate  36 . The ferrite ring  52  forms an inductor in cooperating with a protrusion  48   c , etc. of the heat dissipating member  48  to thereby prevent pulse like charge due to electrostatic discharge from entering the shield  44 . 
         [0080]    Each of four metalic screws  54  for unitizing the heat dissipating member  48 , the substrate  36 , the lower shield member  44 B, and the bottom  46  is screwed from a corresponding tapped hole  48   d  into the bearing  46   a  through a ferrite ring  52 , a through hole  36   a  and a tapped hole  44 Ba. Thus, the heat dissipating member  48  is fixed at a position be brought into contact with or be close enough to the top surface of the CPU  38  and GPU  40  as shown in  FIG. 6 . 
         [0081]      FIG. 7  shows a process continued from  FIG. 5 , and  FIG. 8  shows the result of the  FIG. 7  process. As shown in  FIG. 7 , after completion of the above-described integrating process, the upper shield member  44 A is mounted with the plurality of metalic screws  56  from the top surface side of the substrate  36 . As a result, as shown in  FIG. 8 , the shield  44  is constituted by the upper shield member  44 A and the lower shield member  44 B to shield the inside electromagnetically. 
         [0082]    The upper shield member  44 A is formed with a convex portion  44 Aa at a position corresponding to the heat dissipating member  48 . The convex portion  44 Aa has a height corresponding to the height of the base  48   b  of the heat dissipating member  48 , and has slits  44 Ab for the plurality of heat dissipating fins  48   a  on the top surface. The base  48   b  is directly (or via the thermal conduction sheet  50 ) brought into contact with the CPU  38 , etc. in the shield, and the plurality of heat dissipating fins  48   a  are exposed from the slits  44 Ab to the outside of the shield. Thus, heat emitted by the CPU  38 , etc. is efficiently transmitted to the base  48   b , and dissipated from the plurality of heat dissipating fins  48   a  to the outside of the shield. That is, heat is not stopped within the shield, capable of obtain a high heat dissipating efficiency. 
         [0083]    Then, as shown in  FIG. 9 , a drive unit  54  is arranged at the front of the plurality of heat dissipating fins  48   a  on the top surface of the shield  44 , that is, at a position corresponding to the disk slot  14   a  of the front surface  12   f  of the housing (see  FIG. 1 ). A disk (not illustrated) inserted from the disk slot  14   a  is housed and driven by the drive unit  54 . 
         [0084]    Furthermore, since the drive unit  54  and the plurality of heat dissipating fins  48   a  are proximity to each other, a partition  56  is provided between the drive unit  54  and the plurality of heat dissipating fins  48   a . Flow of air heartened by the plurality of heat dissipating fins  48   a  to the drive unit  54  is prevented by the partition  56 , so that overheating of the drive unit  54  can be reduced. 
         [0085]    Furthermore, an exhaust fan  58  is provided between the USB connector  26  and the peripheral connector  30  at the back of the shield  44 , that is, at a position corresponding to an exhaust hole  28  on the back surface  12   b  of the housing (see  FIG. 2 ). The air heated by the heat dissipating member  48  is exhausted by the exhaust fan  58  from the exhaust hole  28  to the outside of the housing  12 . In accordance with the exhaust, an atmospheric pressure within the housing  12  is reduced to allow cool outside air to be supplied to the inside of the housing  12  through the intake hole  24  on the right side surface  12 R and the intake hole  25  on the bottom surface  12   u . In a case that the covers  18   a  and  18   b  on the left side surface  12 L are opened, outside air is also sucked from the intake hole  27 . 
         [0086]    At this time, in the vicinity of the plurality of heat dissipating fins  48   a , a flow of air shown in  FIG. 12  occurs. Referring to  FIG. 12 , the plurality of heat dissipating fins  48   a  are arranged such that the longest heat dissipating fin F 5  is overlapped with a rotating shaft of the exhaust fan  58 . The partition  56  is arranged vertically to the rotating shaft at a position spaced a predetermined distance b from the lower edge of the heat dissipating fin F 5 . 
         [0087]    Additionally, a positional relationship between the plurality of heat dissipating fins  48   a  and the exhaust fan  58  is not limited to one shown in  FIG. 12 , and may be changeable in view of adding other components thereto. 
         [0088]    Here, when a Y axis is upwardly defined along the exhaust fan  58 , and an X axis is defined in the right direction along the partition  56 , the height of the lower edge of the longest heat dissipating fin F 5  is described to be “Y=b”, and the height of the lower edge of the shortest heat dissipating fin F 1  (or F 9 ) is described to be “Y=a”. Furthermore, the horizontal positions of the heat dissipating fin F 1 -F 9  can be described like X=−4, X=−3, . . . , X=0, . . . , X=4. 
         [0089]    Between the plurality of heat dissipating fins  48   a  and the partition  56 , an intake channel QL is formed along the X axis by the lower left edge portion group T 21  and the partition  56 , and an intake channel QR is formed along the X axis by the lower right edge portion group T 2   r  and the partition  56 . Additionally, these two intake channels QL and QR form a single M-shaped channel. On the other hand, the heat dissipating fins F 1 -F 9  form the eight heat dissipating channels P 1 -P 8  along the Y axis. 
         [0090]    Outside air enters the heat dissipating member  48  from two positions including a space (left opening) between the heat dissipating fin F 1  and partition  56  and a space (right opening) between the heat dissipating fin F 9  and the partition  56 . The air entered from the left opening flows through the intake channel QL in the right direction (X direction), and the air entered from the right opening flows through the intake channel QR in the left direction (−X direction). 
         [0091]    The intake channel QL is narrower in the right direction, and therefore, the amount of air flowing through each position (X=−4, −3, . . . , 0) of the intake channel QL is less as the air progresses to the right. This means that the air entered from the left opening roughly equally flows into the heat dissipating channels P 1 -P 4 . Similarly, the intake channel QR is narrower in the left, and therefore, the amount of air flowing through each position (X=4, 3, . . . , 0) of the intake channel QR is less as the air progresses to the left. This means that the air entered from the right opening roughly equally flows into the heat dissipating channels P 8 -P 5 . 
         [0092]    As understood from the above description, the lower edges of the plurality of heat dissipating fins  48   a  (F 1 -F 9 ) are cut away along the V-shaped line C 1  in the heat dissipating member  48  of this embodiment to thereby form the M-shaped channel (intake channels QL and QR) between the plurality of heat dissipating fins  48   a  and the partition  56 , allowing intake of the large amount of air through the large openings at the right and left. Furthermore, the left half (intake channel QL) of the M-shaped channel is narrower in the right direction, and the right half (intake channel QR) thereof is narrower to the left direction, and therefore, the taken air evenly is spread through the plurality of heat dissipating fins  48   a  (heat dissipating channels P 1 -P 8 ). Thus, a high heat dissipating advantage can be obtained. 
         [0093]    Additionally, in the heat dissipating member  48  of this embodiment, the lower edge portion group (T 2 ) of the plurality of heat dissipating fins  48   a  is cut away along the V-shaped line C 11  as shown in  FIG. 12 . On the other hand, as shown in  FIG. 13 , the lower edge portion group (T 2 ) of the plurality of heat dissipating fins  48   a  may be cut away along the single line C 2  inclined with respect to the partition  56 , and an intake hole may be formed at a position corresponding to the notch on the left side surface  12 L of the housing. In this case also, a large amount of air can mainly be taken from the left opening (the space between the heat dissipating fin F 1  and the partition  56 ) into the intake channel QL, and the air can evenly be spread into the entire heat dissipating fin  48   a  (heat dissipating channels P 1 -P 8 ). 
         [0094]    According to  FIG. 13  configuration, the differences between the lower edge portion of the plurality of heat dissipating fins  48   a  can be smaller than that shown in  FIG. 12  while the lengths of spaces a and b are ensured as in  FIG. 12 . That is, it is possible to make the slant of the single line C 2  gentle. 
         [0095]    Therefore, in accordance with the configuration in  FIG. 13 , it is possible to make a ventilating resistance less, and make an air flow from the above described intake hole on the left side surface  12 L of the housing to the intake channel QL smooth. Thus, it is possible to obtain a high heat dissipating effect. 
         [0096]    Also, it may be possible that the space b shown in  FIG. 13  is further large to make the slant of the single line C 2  gentler. 
         [0097]    In addition, the V-shaped line C 1  at a time of cutting away the lower edges of the plurality of heat dissipating fins  48   a  (F 1 -F 9 ) may be left-right asymmetry as shown in  FIG. 14(A) . Furthermore, the pattern of cutting away may be U-shaped (or angular) as shown in  FIG. 14  (B) without being limited to the V-shaped. In a case of utilizing a curve, the curvature may be changed depending on the position as shown in  FIG. 14  (C). 
         [0098]    Generally, if the lower edge portion group of the plurality of heat dissipating fins  48   a  is cut away along a curve or a line which monotonously decreases on the left side and monotonously increases on the right side with respect to a minimum value, a large amount of air can be taken from the large openings at the right and left, and can be spread into the entire of the plurality of heat dissipating fins  48   a , capable of obtaining a high heat dissipating effect. 
         [0099]    Furthermore, in this embodiment, the spaces of the plurality of heat dissipating fins  48   a  (space between each of the heat dissipating channels P 1 -P 8 ) are equal, but may be changeable depending a position in the X direction. One example is shown in  FIG. 15 . Referring to  FIG. 15 , each of the widths d 1 -d 8  respectively corresponding to the heat dissipating channels P 1 -P 8  is longest at the channel P 4  and P 5  adjacent to the longest heat dissipating fin F 5 , and becomes narrower as the distance is away from the heat dissipating fin F 5  (that is, d 1 &lt;d 2 &lt;d 3 &lt;d 4 , d 5 &gt;d 6 &gt;d 7 &gt;d 8 ). 
         [0100]    Generally, a fluid like air is difficult to flow in a longer channel in the same width. Here, it is though that it is possible to uniform the flow of air by making the heat dissipating channel P 1 -P 8  have a width corresponding to the length. It should be noted that by making the width of the heat dissipating channel wider, a heat dissipating area becomes small, and therefore, the heat dissipating advantage is not always heightened. 
         [0101]    Furthermore, on the base  48   b  of the heat dissipating member  48 , there is an area on which the heat dissipating fins  48   a  are not arranged as a result of the cut-away, but such an empty area may be removed as shown in  FIG. 16 . However, in this embodiment, the CPU  38  and the GPU  40  also exist directly under the empty area, and the empty area also functions so as to transmit heat of the CPU  38 , etc. to the plurality of heat dissipating fins  48   a . Furthermore, since a part of the drive unit  54  is placed above the empty area (see FIG.  10 (A)), the empty area functions so as to prevent the heat of the CPU  38 , etc. from being directly transmitted to the drive unit  54 . In such a case, it is preferable that the empty area is not removed. 
         [0102]    It should be noted that the function of the above-described empty area is independent of the shape of the notch pattern (by extension, the alignment of the plurality of heat dissipating fins  48   a ). Thus, for example as shown in  FIG. 17 , the lower edge portion group of the plurality of heat dissipating fins  48   a  may simply be cut away in parallel with the bottom L 2  of the base  48   b . By arranging a part of components such as the drive unit  54 , etc. in the empty area, it is possible to realize space saving. 
         [0103]    Furthermore, in this embodiment, the edge portion group T 1  of the plurality of heat dissipating fins  48   a  on the side of the exhaust fan  58  is arranged on the line vertical to the plurality of heat dissipating fins  48   a  (top L 1  of the base  48   b ) (see  FIG. 10  (A)), but may be arranged along a inclined line or a curve with respect to the plurality of heat dissipating fins  48   a.    
         [0104]    Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims.

Technology Classification (CPC): 6