Patent Publication Number: US-2023152867-A1

Title: Electronic apparatus

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to an electronic apparatus including a fan device. 
     Description of the Related Art 
     The present applicant has proposed an electronic apparatus, such as a laptop PC, in which a keyboard device at the top of a chassis has an opening for taking in outside air (see Japanese Patent No. 6846547). 
     SUMMARY OF THE INVENTION 
     The opening in Japanese Patent No. 6846547 includes a notch formed in a frame partitioning each key cap and a through hole formed in a plate-shaped member supporting each key cap. Both the notch and the through hole of this opening are provided only above a fan device. Such a structure has been found to be limited in improving cooling performance by increasing the air intake volume of the fan device. Meanwhile, the keyboard device is required to have high rigidity and strength because it is operated directly by a user. Simply increasing the installation range of the opening causes the keyboard device to decrease in rigidity and decrease in operability and texture. 
     A keyboard device mounted in an electronic apparatus such as a laptop PC easily conducts heat in a chassis, which is likely to cause user discomfort. In particular, in the keyboard device in Japanese Patent No. 6846547, each key cap is surrounded by the frame. In such a structure, there is little escape of heat transferred from inside the chassis to the keyboard device. This further worsens the problem of temperature rise. 
     A main object of the present invention is to provide an electronic apparatus that can improve cooling performance while suppressing decreases in operability and texture of a keyboard device. Another object of the present invention is to provide an electronic apparatus that can suppress temperature rise of a keyboard device located at the top of a chassis. 
     An electronic apparatus according to a first aspect of the present invention includes: a chassis; a keyboard device located at a top of the chassis, and including a plurality of key caps, a plate-shaped member that is located below the plurality of key caps and supports each of the plurality of key caps, and an opening formed through the plate-shaped member in a top-bottom direction; a frame supported on a top surface of the plate-shaped member, and including key arrangement holes in which the plurality of key caps are arranged and partition walls that surround the key arrangement holes to partition adjacent key caps from each other; and a fan device located in the chassis, and including an intake port on a top surface thereof, wherein at least part of the partition walls has a bottom edge surface notched to form an air flow path between the notched bottom edge surface and the top surface of the plate-shaped member, to have a communicating path through which adjacent key arrangement holes communicate, and wherein a height of the communicating path in a region not overlapping with the fan device is lower than a height of the communicating path in a region overlapping with the fan device, in a plan view of the chassis. 
     An electronic apparatus according to a second aspect of the present invention includes: a chassis; a keyboard device located at a top of the chassis, and including a plurality of key caps and a plate-shaped member that is located below the plurality of key caps and supports each of the plurality of key caps; and a frame supported on a top surface of the plate-shaped member, and including key arrangement holes in which the plurality of key caps are arranged and partition walls that surround the key arrangement holes to partition adjacent key caps from each other, wherein at least part of the partition walls has a bottom edge surface notched to form an air flow path between the notched bottom edge surface and the top surface of the plate-shaped member, to have a communicating path through which adjacent key arrangement holes communicate, and wherein the frame has at least a first region including a plurality of partition walls in which the communicating path has a first height, and a second region including a plurality of partition walls in which the communicating path has a second height lower than the first height. 
     An electronic apparatus according to a third aspect of the present invention includes: a chassis; a keyboard device located at a top of the chassis, and including a plurality of key caps and a plate-shaped member that is located below the plurality of key caps and supports each of the plurality of key caps; and a frame supported on a top surface of the plate-shaped member, and including key arrangement holes in which the plurality of key caps are arranged and partition walls that surround the key arrangement holes to partition adjacent key caps from each other, wherein at least part of the partition walls has a communicating path through which adjacent key arrangement holes communicate, and wherein the frame has at least a first region including a plurality of partition walls in which the communicating path has a first cross-sectional area, and a second region including a plurality of partition walls in which the communicating path has a second cross-sectional area smaller than the first cross-sectional area. 
     The above-described aspects of present invention can improve cooling performance while suppressing decreases in operability and texture of a keyboard device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic plan view of an electronic apparatus according to an embodiment as seen from above. 
         FIG.  2    is an enlarged side sectional view of essential parts schematically illustrating the internal structure of a chassis. 
         FIG.  3    is an enlarged perspective view of part of a frame as seen obliquely from above. 
         FIG.  4    is a bottom view of a cover member  21  formed integrally with the frame. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Preferred embodiments of an electronic apparatus according to the present invention will be described in detail below, with reference to the accompanying drawings. 
       FIG.  1    is a schematic plan view of an electronic apparatus  10  according to an embodiment as seen from above. As illustrated in  FIG.  1   , the electronic apparatus  10  includes a chassis  14  in which a keyboard device  12  is mounted, and a display chassis  18  in which a display  16  is mounted. The electronic apparatus  10  is a clamshell laptop PC in which the chassis  14  and the display chassis  18  are relatively rotatably connected by a hinge  20 .  FIG.  1    illustrates a state in which the electronic apparatus  10  is in use form with the display chassis  18  being opened from the chassis  14 . The electronic apparatus  10  may be an electronic apparatus other than clamshell type. 
     The display chassis  18  is a thin flat box body. The display chassis  18  has the display  16  mounted therein. The display  16  is, for example, an organic EL display or a liquid crystal display. 
     The chassis  14  and each element mounted in the chassis  14  will be described below. Hereafter, based on a posture of operating the keyboard device  12  illustrated in  FIG.  1   , the near side is referred to as “front”, the far side as “rear”, the width direction as “left-right direction”, and the height direction (the thickness direction of the chassis  14 ) as “top-bottom direction”. 
       FIG.  2    is an enlarged side sectional view of essential parts schematically illustrating the internal structure of the chassis  14 . 
     The chassis  14  is a thin flat box body. The chassis  14  includes a cover member  21  that forms a top surface  14   a  and four side surfaces, and a plate-shaped cover member  22  that forms a bottom surface  14   b . The cover members  21  and  22  are overlapped in the thickness direction and detachably connected to each other. The rear edge of the chassis  14  is connected to the display chassis  18  using the hinge  20 . 
     The cover member  21  at the top has an opening  21   a  into which the keyboard device  12  is inserted from below. The cover member  21  may have a shallow bathtub-like recessed portion instead of the opening  21   a , and the keyboard device  12  may be placed on the bottom plate of the recessed portion from above. The cover members  21  and  22  are, for example, made of metal such as magnesium. 
     The keyboard device  12  and a touch pad  24  are provided on the top surface  14   a  of the chassis  14 . The keyboard device  12  constitutes most of the top surface  14   a . A board  26  and a cooling module  28  are housed inside the chassis  14 . Various electronic components such as a battery device, mechanical components, and the like are also provided inside the chassis  14 . 
     The board  26  is a motherboard of the electronic apparatus  10 . The board  26  is a printed board on which a central processing unit (CPU)  30  is mounted. Various electronic components such as a graphics processing unit (GPU), a communication module, memory, and connection terminals are also mounted on the board  26 . The board  26  is located below the keyboard device  12 . The board  26  is screwed to the back surface of the keyboard device  12  and the inner surface of the cover member  21 , and thus is fixed to the chassis  14 . The board  26  has a top surface that serves as a mounting surface for the cover member  21 , and a bottom surface that serves as a mounting surface for the CPU  30  and the like. 
     The CPU  30  is a processing device that performs operations related to main control and processing of the electronic apparatus  10 . The CPU  30  is the largest heating element among the devices mounted in the electronic apparatus  10 . 
     The cooling module  28  is a device that absorbs heat mainly generated by the CPU  30 , transports the absorbed heat, and discharges it to the outside of the chassis  14 . The cooling module  28  can also discharge the heat of heating elements other than the CPU  30 , such as the GPU, to the outside of the chassis  14 . Most of the cooling module  28  is located below the board  26 . The cooling module  28  is screwed to the bottom surface of the board  26 , the back surface of the keyboard device  12 , the inner surface of the cover member  21 , and the like, and thus is fixed to the chassis  14 . 
     The cooling module  28  includes fan devices  32  and  33 , cooling fins  34  and  35 , and a heat pipe  36 . 
     The cooling module  28  in this embodiment is used for cooling the CPU  30  and the GPU, and accordingly includes one pair of fan devices and one pair of cooling fins. Depending on the object to be cooled, the required capacity, etc., the cooling module  28  may include one fan device and one cooling fin. The fan devices  32  and  33  have the same or similar basic structure, except that they are slightly different in size and shape. The cooling fins  34  and  35  have the same or similar basic structure, except that they are slightly different in size and shape. Hence, the fan device  32  and the cooling fins  34  will be described below as representative examples, while omitting the description of the fan device  33  and the cooling fin  35 . 
     The fan devices  32  and  33  are respectively arranged near the left and right rear corners of the chassis  14  (see  FIG.  1   ). As illustrated in  FIG.  2   , the fan device  32  includes a fan chassis  40 , a rotating part  41 , and an impeller  42 . The fan device  32  is a centrifugal fan in which the rotating part  41  rotates by a motor to cause the impeller  42  located on the outer peripheral side of the rotating part  41  to rotate. 
     The fan chassis  40  is a flat box body that houses the rotating part  41  and the impeller  42 . The fan chassis  40  has a bottom plate  40 A, a top plate  40 B, and a side plate  40 C. The plates  40 A to  40 C are, for example, metal plates. 
     The bottom plate  40 A is an approximately bullet-shaped thin plate obtained by forming one side of a rectangular plate into a circular shape. The bottom plate  40 A forms the bottom surface  32   a  of the fan device  32 . The bottom plate  40 A has a bottom intake port  44 . The bottom intake port  44  is a through hole in, for example, a circular shape, a donut shape, or a shape in which a plurality of ellipses are arranged in the circumferential direction. 
     The top plate  40 B is a thin plate having the same outer shape as the bottom plate  40 A. The top plate  40 B forms the top surface  32   b  of the fan device  32 . The top plate  40 B has a top intake port  45 . The top intake port  45  may have the same or similar shape as the bottom intake port  44 . The intake ports  44  and  45  are openings for taking in air outside the fan chassis  40  by the rotation of the impeller  42 . 
     The side plate  40 C is a curved plate that covers the sides of the inside space of the fan chassis  40  formed between the bottom plate  40 A and the top plate  40 B. The side plate  40 C in this embodiment is formed integrally with the top plate  40 B. The side surface of the fan chassis  40  facing the rear has an opening as a result of the side plate  40 C not being present or the side plate  40 C having a hole. This opening serves as the exhaust port  46  of the fan device  32 . The exhaust port  46  faces the cooling fin  34 . 
     The front surfaces of the cooling fins  34  and  35  are located just behind the fan devices  32  and  33  respectively, and each face the corresponding exhaust port  46 . The rear surfaces of the cooling fins  34  and  35  each face the corresponding chassis exhaust port  14   c  that opens on the rear side surface of the chassis  14 . The cooling fin  34  has a structure in which a plurality of plate-shaped metal fins are arranged at equal intervals in the left-right direction on the surface of a plate. Each fin stands in the top-bottom direction, and extends in the front-rear direction. A gap through which the air sent from the fan device  32  passes is formed between adjacent fins. The cooling fin  34  is thermally connected to the CPU  30  via the heat pipe  36 . 
     The heat pipe  36  is a pipe-shaped heat transport device. One heat pipe  36  or a set of two or more heat pipes  36  is used. The heat pipe  36  is formed by crushing a metal pipe into a thin flat shape to form an elliptical cross-section and enclosing a working fluid in the inside sealed space. The heat pipe  36  may be a known heat pipe. The heat pipe  36  has, for example, a heat absorbing portion at one end thermally connected to the CPU  30  and a heat radiating portion at the other end connected to the cooling fins  34  and  35 . 
     In the cooling module  28 , the heat of the CPU  30  and the like carried by the heat pipe  36  is transferred to the cooling fins  34  and  35 . The heat transferred to the cooling fins  34  and  35  is discharged to the outside of the chassis  14  through the chassis exhaust port  14   c , by blast air from the exhaust ports  46  of the fan devices  32  and  33 . Reference symbols  47  and  48  in  FIG.  1    are plate-shaped heat transport devices for diffusing the heat of the CPU  30  and the like, and are, for example, metal plates or vapor chambers. 
     As illustrated in  FIGS.  1  and  2   , the keyboard device  12  includes a plurality of key switches  50 , a plate-shaped member  52 , and a frame  54 . 
     Each key switch  50  is supported on the top surface  52   a  side of the plate-shaped member  52 . Each key switch  50  has a key cap  56  supported by a guide mechanism  50   a  and a rubber dome  50   b  so as to be movable in the top-bottom direction. The guide mechanism  50   a  is a scissor mechanism that connects the bottom surface of the key cap  56  and the top surface of the plate-shaped member  52 . The rubber dome  50   b  is a dome-shaped member made of a flexible elastic material such as silicone rubber. The rubber dome  50   b  is located at the center of the guide mechanism  50   a , and is interposed between the key cap  56  and the plate-shaped member  52 . Each keycap  56  is made of resin as an example, and has an approximately rectangular shape in a plan view. Each keycap  56  has side walls hanging down from four peripheral edges of a top plate forming an operation surface. 
     As illustrated in  FIG.  1   , a pointing stick  51  is provided approximately at the center of the keyboard device  12 . The pointing stick  51  is an operation device that substitutes for a mouse. 
     The plate-shaped member  52  is formed by laminating a membrane sheet  57 , a base plate  58 , and a light guide plate  59  in this order from top to bottom. The membrane sheet  57  is, for example, a switch sheet with a three-layer structure that closes a contact when pressed. The contact of the membrane sheet  57  is closed by the rubber dome  50   b  that is compressed when the keycap  56  is pressed down. The base plate  58  is a metal plate having cut-and-raised portions and holes formed at various locations. The light guide plate  59  is a transparent resin plate that guides the light emitted by a light source attached to the bottom surface in the left-right direction, reflects the light on the light reflection surface, and irradiates each keycap  56  from the back surface. The light guide plate  59  may be omitted. In such a case, a waterproof sheet may be laminated on the bottom surface of the base plate  58 . 
     The frame  54  is a mesh plate made of resin, metal, or the like. The frame  54  partitions each keycap  56 . The frame  54  has a plurality of key arrangement holes  65  in which the key caps  56  are arranged so as to be movable in the top-bottom direction. That is, the frame  54  has partition walls  66  that partition adjacent key caps  56 , and each space surrounded by the partition walls  66  on all four sides is the key arrangement hole  65 . 
     The frame  54  is fixed as a result of the bottom edge surface  67  of each partition wall  66  being supported by the top surface  52   a  of the plate-shaped member  52 . In this embodiment, the frame  54  is formed integrally with the cover member  21  (see  FIG.  4   ). The frame  54  may be formed separately from the cover member  21 . In this case, the frame  54  is fixed to the plate-shaped member  52  and substantially forms part of the keyboard device  12 . 
     As illustrated in  FIG.  2   , the chassis  14  has a bottom communicating hole  60  for allowing air A to flow to the inside from the bottom surface  14   b . Dashed-dotted arrow A in  FIG.  2    schematically indicates the flow of air. 
     
       
     
     The bottom communicating hole  60  is a through hole formed in the cover member  22  forming the bottom surface  14   b  of the chassis  14 . The bottom communicating hole  60  has, for example, a structure in which a plurality of slit-like holes are arranged side by side. The bottom communicating hole  60  is provided at a position overlapping with the bottom intake port  44  of each of the fan devices  32  and  33  in a plan view, and faces the bottom intake port  44 . 
     As illustrated in  FIG.  2   , the chassis  14  has a top communicating hole  62  for allowing air A to flow to the inside from above. 
     The top communicating hole  62  is a through hole formed through the keyboard device  12  in the top-bottom direction, and communicates with the top intake port  45  of each of the fan devices  32  and  33 . The top communicating hole  62  is formed as a result of the gap between the adjacent key cap  56  and partition wall  66 , each of communicating paths  54   a  to  54   c , and an opening  61  communicating in this order from top to bottom. The communicating paths  54   a  to  54   c  are each formed by notching the bottom edge surface  67  of the partition wall  66  to form the flow path of air A. The communicating paths  54   a  to  54   c  will be described in detail later. The openings  61  are each a through hole formed in the plate-shaped member  52 . For example, the openings  61  are a plurality of rectangular long holes located below lateral wall portions  66   a  of the frame  54  along the left-right direction and extending in the left-right direction. The shape of each opening  61  may be the same as or similar to that of the top intake port  45 . 
     Thus, as illustrated in  FIG.  2   , each of the fan devices  32  and  33  draws air A below the chassis  14  from the bottom communicating hole  60  of the cover member  22  through the bottom intake port  44 . Simultaneously, each of the fan devices  32  and  33  draws air A above the chassis  14  from the top communicating hole  62  through the top intake port  45 . Each of the fan devices  32  and  33  air-cools the corresponding one of the cooling fins  34  and  35  when the air A sucked from the intake ports  44  and  45  is discharged from the exhaust port  46  to the outside of the chassis  14 . Hence, the fan devices  32  and  33  can sufficiently take in air from the top and bottom of the chassis  14 , with it being possible to achieve high cooling efficiency. 
     Reference symbols  63   a  and  63   b  in  FIG.  2    are sealing materials made of sponge or the like. The sealing material  63   a  forms a cutoff wall around the bottom intake port  44 . The sealing material  63   b  forms a cutoff wall around the top intake port  45 . When a liquid such as beverage is spilled on the keyboard device  12 , the sealing members  63   a  and  63   b  prevent the liquid from entering the board  26  and the like in the chassis  14 . 
     The specific structure of the communicating paths  54   a  to  54   c  formed in the frame  54  will be described below.  FIG.  3    is an enlarged perspective view of part of the frame  54  as seen obliquely from above.  FIG.  4    is a bottom view of the cover member  21  formed integrally with the frame  54 . 
     In  FIG.  4   , the communicating path  54   a  is indicated by a slant line pattern inclined in the direction of approximately 2 o&#39;clock (8 o&#39;clock) in clock position. The communicating path  54   b  is indicated by a dot pattern. The communicating path  54   c  is indicated by a slant line pattern inclined in the direction of approximately 10 o&#39;clock (4 o&#39;clock) in clock position. 
     As illustrated in  FIGS.  2  and  3   , the communicating paths  54   a  to  54   c  communicate between the key placement holes  65  partitioned by the partition wall  66  to allow air A to move. The bottom edge surface  67  of the frame  54  is supported by the top surface  52   a  of the plate-shaped member  52 . The communicating paths  54   a  to  54   c  are recessed portions formed by cutting the frame  54  upward from the bottom edge surface  67  side. The communicating paths  54   a  to  54   c  thus serve as tunnels that communicate between adjacent key arrangement holes  65 . The communicating paths  54   a  to  54   c  may be formed during molding of the frame  54 , or formed by machining or the like after the molding of the frame  54 . 
     The partition wall  66  of the frame  54  has a lateral wall portion  66   a  extending in the left-right direction of the keyboard device  12  and a longitudinal wall portion  66   b  extending in the front-rear direction of the keyboard device  12 . The communicating paths  54   a  to  54   c  in this embodiment are formed in both the lateral wall portion  66   a  and the longitudinal wall portion  66   b  (see  FIGS.  3  and  4   ). The communicating paths  54   a  to  54   c  may be formed in only one of the lateral wall portion  66   a  and the longitudinal wall portion  66   b.    
     As illustrated in  FIG.  4   , the communicating path  54   a  is provided in a first region R 1  including the position overlapping with each of the left and right fan devices  32  and  33  and its periphery in a plan view of the cover member  21 , i.e., a plan view of the chassis  14 . The communicating path  54   b  is provided in a second region R 2  surrounding the first region R 1 . The communicating path  54   c  is provided in a third region R 3  surrounding the second region R 2 . In this embodiment, the communicating paths  54   b  and  54   c  are located so as not to overlap with the left and right fan devices  32  and  33 . 
     In the structural example illustrated in  FIG.  4   , the fan devices  32  and  33  are arranged at the left and right rear corners of the frame  54 . Accordingly, the second region R 2  has an approximately L shape so as to surround not the entire periphery but approximately two sides of the first region R 1 . The third region R 3  has an approximately linear shape so as to surround not the entire periphery but approximately one side of the second region R 2 . The second region R 2  may surround one side or three or more sides of the first region R 1 . The third region R 3  may surround two or more sides of the second region R 2 . 
     Thus, the communicating paths  54   a  to  54   c  are provided in most of the frame  54 , and the regions R 1  to R 3  are arranged in order and are continuous. In this way, the communicating paths  54   a  to  54   c  form air flow paths that communicate between all of the plurality of key arrangement holes  65  in the regions R 1  to R 3 , on the top surface  52   a  of the plate-shaped member  52 . 
     Specifically, as illustrated in  FIG.  4   , the communicating paths  54   a  to  54   c  form an air flow path that continues from the third region R 3  through the second region R 2  to the first region R 1 . In this embodiment, a pair of left and right air flow paths are provided so as to correspond to the left and right fan devices  32  and  33 . 
     A fourth region R 4  is formed at the center between the left regions R 1  to R 3  and the right regions R 1  to R 3 . The fourth region R 4  extends in the front-rear direction at approximately the center of the frame  54 . The partition wall  66  located in the fourth region R 4  does not have the communicating paths  54   a  to  54   c . That is, the fourth region R 4  is a shielding wall that partitions the air flow paths in the left regions R 1  to R 3  corresponding to the left fan device  32  and the air flow paths in the right regions R 1  to R 3  corresponding to the right fan device  33 . 
     The fourth region R 4  in this embodiment has, for example, a stepped mountain shape in a plan view in  FIG.  4   . Thus, the fourth region R 4  extends to a range including the pointing stick  51  while forming a shielding wall between the left regions R 1  to R 3  and the right regions R 1  to R 3 . The fourth region R 4  may be omitted, and all of the partition walls  66  may be provided with the communicating paths  54   a  to  54   c.    
     As illustrated in  FIG.  3   , the height of each of the communicating paths  54   a  to  54   c  is denoted by H. The height H substantially refers to the height from the top surface  52   a  of the plate-shaped member  52  to the ceiling of the corresponding one of the communicating paths  54   a  to  54   c . That is, the height H indicates the height of the air flow path formed by the corresponding one of the communicating paths  54   a  to  54   c . As illustrated in  FIG.  2   , the heights H of the communicating paths  54   a  to  54   c  are different. Hereafter, the height H of the communicating path  54   a  is referred to as a first height, the height H of the communicating path  54   b  as a second height, and the height H of the communicating path  54   c  as a third height. 
     In this embodiment, the first height of the communicating path  54   a  is highest, the third height of the communicating path  54   c  is lowest, and the second height of the communicating path  54   b  is an intermediate height between the first height and the third height. In this embodiment, the first height is set to 0.5 mm, the second height to 0.3 mm, and the third height to 0.1 mm. Therefore, the communicating paths  54   a  to  54   c  are arranged stepwise so that the height H gradually decreases in the direction away from the first region R 1  overlapping with each of the fan devices  32  and  33  (see  FIGS.  2  and  5   ). 
     As described above, in the electronic apparatus  10  in this embodiment, at least part of the partition walls  66  has the communicating paths  54   a  to  54   c . The height H of each of the communicating paths  54   b  and  54   c  in the regions R 2  and R 3  that do not overlap with the fan devices  32  and  33  is lower than the height H of the communicating path  54   a  in the first region R 1  that overlaps with the fan devices  32  and  33 . 
     Thus, in the electronic apparatus  10 , not only the communicating path  54   a  is provided in the first region R 1  that overlaps with the fan devices  32  and  33  but also the communicating paths  54   b  and  54   c  are provided in the partition walls  66  in the regions R 2  and R 3  that do not overlaps with the fan devices  32  and  33 . Therefore, as illustrated in  FIG.  2   , each of the fan devices  32  and  33  can draw air from a wide range including not only the communicating path  54   a  located directly above but also the other communicating paths  54   b  and  54   c . In such electronic apparatus  10 , the air volume of the fan devices  32  and  33  increases, and the cooling performance of the cooling module  28  is improved. 
     The height H of each of the communicating paths  54   b  and  54   c  in the regions R 2  and R 3  that do not overlap with the fan devices  32  and  33  is lower than the height H of the communicating path  54   a  in the first region R 1  that overlaps with the fan devices  32  and  33 . Therefore, despite the communicating paths  54   a  to  54   c  being formed in a wide range of partition walls  66 , the decrease in strength and rigidity of the frame  54  as a whole is minimum. Consequently, the electronic apparatus  10  can suppress decreases in operability and texture of the keyboard device  12 . This is because the communicating paths  54   b  and  54   c  lower in height H have less influence on the decrease in rigidity of the frame  54  than the communicating path  54   a  higher in height H. 
     Moreover, in the electronic apparatus  10 , the height H of the communicating path  54   a  in the first region R 1  that overlaps with each of the fan devices  32  and  33  is highest, so that the decrease in the amount of intake air from the top intake port  45  due to the communicating path  54   a  as a bottleneck can be prevented. 
     For the electronic apparatus  10  in this embodiment including the communicating paths  54   a  to  54   c  and an electronic apparatus of a comparative example including the communicating path  54   a  only directly above each of the fan devices  32  and  33 , an experiment of measuring the surface temperature of the keyboard device  12  and an experiment of comparing the fan air volume by visually observing the amount of smoke sucked in were conducted. As a result, in the surface temperature measurement experiment, in the electronic apparatus  10  in this embodiment, the temperature of the entire top surface  14   a  of the chassis  14  was lower than in the comparative example, and the temperature of a part directly above each of the fan devices  32  and  33  that tends to be high in temperature, such as a part directly above each of the fan devices  32  and  33 , was lower than in the comparative example. In the experiment of comparing the air volume of the fan devices  32  and  33 , in the electronic apparatus  10  in this embodiment, the amount of sucked smoke was greater and the fan air volume was greater than in the comparative example. 
     The partition wall  66  has the lateral wall portion  66   a  extending in the left-right direction and the longitudinal wall portion  66   b  extending in the front-rear direction. The communicating paths  54   a  to  54   c  are formed in both the lateral wall portion  66   a  and the longitudinal wall portion  66   b . Therefore, as illustrated in  FIGS.  2  and  4   , in the electronic apparatus  10 , air A smoothly flows toward the communicating path  54   a  through the other communicating paths  54   b  and  54   c . Hence, in the electronic apparatus  10 , the air volume of the fan devices  32  and  33  can be further increased and the cooling performance can be further improved. Meanwhile, forming the communicating paths  54   a  to  54   c  in the lateral wall portion  66   a  and the longitudinal wall portion  66   b  in this way is likely to cause a decrease in the rigidity of the frame  54 . Such decrease in the rigidity of the frame  54  can, however, be minimized by making the heights H of the communicating paths  54   a  to  54   c  different in the electronic apparatus  10 . 
     The number of types of communicating paths that differ in height may be other than three, for example, may be two, or four or more. For example, consider the case where the number of types of communicating paths that differ in height is two and the communicating path  54   c  is omitted. In this case, for example, the communicating path  54   b  needs to be provided over a wide range including the regions R 2  and R 3  in order to ensure the air flow rate, which may cause a decrease in the rigidity of the frame  54 . It is therefore preferable that there are the three different communicating path heights illustrated in  FIG.  4    or four or more different communicating path heights and such communicating paths are arranged stepwise, from the viewpoint of the rigidity of the frame  54  and smooth air circulation in the frame  54 . Even in a structure in which the number of types of communicating paths that differ in height is two, the rigidity of the frame  54  can be maintained higher than in the case where the number of types of communicating paths that differ in height is one. A structure in which the number of types of communicating paths that differ in height is two is therefore sufficiently effective depending on conditions such as the material and size of the frame  54 . 
     The above describes an example in which the communicating paths  54   a  to  54   c  are formed as notch-shaped recessed portions and made different in height H to achieve both improving the cooling performance of the cooling module  28  and ensuring the rigidity of the frame  54 . Alternatively, the communicating paths  54   a  to  54   c  may be formed, for example, by making part of the partition walls  66  thinner in the top-bottom direction, or formed as through holes in the partition walls  66 . The electronic apparatus  10  may achieve both improving the cooling performance of the cooling module  28  and ensuring the rigidity of the frame  54 , by forming the communicating paths  54   a  to  54   c  by thinning part of the partition walls  66  or forming through holes in the partition walls  66  and also making the communicating paths  54   a  to  54   c  different in cross-sectional area (flow path cross-sectional area). In this case, the electronic apparatus  10  may be configured so that the cross-sectional area (second cross-sectional area) of the communicating path  54   b  in the second region R 2  is smaller than the cross-sectional area (first cross-sectional area) of the communicating path  54   a  in the first region R 1  and the cross-sectional area (third cross-sectional area) of the communicating path  54   c  in the third region R 3  is smaller than the second cross-sectional area. 
     The electronic apparatus  10  includes the pair of left and right fan devices  32  and  33 . The frame  54  has the fourth region R 4  in which the communicating path  54   a  and the like are not formed in the partition wall  66  between the pair of fan devices  32  and  33  in a plan view of the chassis  14 . That is, in the electronic apparatus  10 , the intake range of the left fan device  32  and the intake range of the right fan device  33  are separated by the fourth region R 4  serving as a shielding wall. The electronic apparatus  10  can thus prevent unbalanced air circulation, such as the air intake amount of the fan device  32  decreasing significantly, caused by an overlap of the air intake ranges of the left and right fan devices  32  and  33 . As a result, the cooling performance in the electronic apparatus  10  can be further stabilized and improved. 
     The fourth region R 4  in this embodiment includes the installation region of the pointing stick  51 . Since the pointing stick  51  is operated while being pressed by the user, the pointing stick  51  is required to have even higher rigidity than each keycap  56 . In the electronic apparatus  10 , no communicating path is provided in the partition wall  66  around the installation position of the pointing stick  51  (see  FIG.  4   ), so that the decrease in the mounting rigidity of the pointing stick  51  can be prevented. 
     In the electronic apparatus  10 , as a result of the communicating paths  54   a  to  54   c  being provided in a wide range of the frame  54 , the heat transferred from the CPU  30  and the like to the plate-shaped member  52  can be dissipated by the flow of air A passing through the communicating paths  54   a  to  54   c . Accordingly, in the electronic apparatus  10 , the top communicating hole  62  formed through the keyboard device  12  is not essential. That is, even if the electronic apparatus  10  does not have the top communicating hole  62 , the outside air can easily flow over a wide area of the top surface  52   a  of the plate-shaped member  52  through the communicating paths  54   a  to  54   c , and the temperature rise of the keyboard device  12  can be prevented. In this case, it is desirable that as many communicating paths  54   a  to  54   c  as possible are provided. Preferably, the communicating paths  54   a  to  54   c  are provided in all partition walls  66 . 
     The present invention is not limited to the above-described embodiments, changes can be freely made without departing from the gist of the present invention.