Patent Publication Number: US-2022232729-A1

Title: Electronic apparatus

Description:
FIELD OF THE INVENTION 
     The present invention relates to an electronic apparatus having a plurality of chassis connected by a hinge device. 
     BACKGROUND OF THE INVENTION 
     In recent years, electronic apparatuses such as tablet PCs and smartphones, which have a touch panel type liquid crystal display and do not have a physical keyboard, are rapidly becoming widespread. While it is desirable that the display of this type of electronic apparatus be large when in use, it is also desirable that the display can be made small when not in use. Thus, there has been proposed an electronic apparatus configured such that not only the chassis but also the display can be folded by using a flexible display such as an organic EL (Electroluminescence) (refer to, for example, Japanese Unexamined Patent Application Publication No. 2018-112833). 
     SUMMARY OF THE INVENTION 
     For electronic apparatuses such as those described above, there is a high demand for smaller and thinner chassis. It is also necessary to secure a space for accommodating a display that can be folded into an arc shape in the chassis. Therefore, in this type of electronic apparatus, it is difficult in some cases to secure a space for installing a cooling device having a high cooling capability required for cooling heat generating elements such as a CPU. As a result, there is a concern that the electronic apparatus may develop the deterioration of the capability of a CPU or the like, or develop a localized high temperature portion (hot spot) on the outer surface of the chassis. 
     The present invention has been made in consideration of the problems with the prior art described above, and an object of the invention is to provide an electronic apparatus capable of securing a sufficient cooling capability. 
     An electronic apparatus according to the first aspect of the present invention includes: a first chassis in which a heat generating element is mounted; a second chassis adjacent to the first chassis; a hinge that connects the first chassis and the second chassis such that the first chassis and the second chassis can be rotated relative to each other between a 0-degree attitude, at which the first chassis and the second chassis are stacked to overlap each other in a surface normal direction, and a 180-degree attitude, at which the first chassis and the second chassis are mutually arranged in a direction perpendicular to the surface normal direction; and a display having a fold region that is provided across the first chassis and the second chassis and is folded as the first chassis and the second chassis rotate relative to each other, wherein the hinge device has a hinge main body made of a metal that extends along adjacent end portions of the first chassis and the second chassis and is placed so as to stretch across the adjacent end portions, a first support plate made of a metal that extends along the adjacent end portions on an inner surface side of the first chassis, is connected to the hinge main body in a relatively rotatable manner, is provided so as to be relatively movable with respect to the inner surface of the first chassis, and supports a back surface of the display between the 0-degree attitude and the 180-degree attitude, and a second support plate made of a metal that extends along the adjacent end portions on an inner surface side of the second chassis, is connected to the hinge main body in a relatively rotatable manner, is provided so as to be relatively movable with respect to the inner surface of the second chassis, and supports the back surface of the display between the 0-degree attitude and the 180-degree attitude, the electronic apparatus further including a flexible heat conductive member inside the first chassis, and the heat conductive member thermally connecting a heat receiving member that receives heat from the heat generating element and the first support plate. 
     The above-described aspect of the present invention can secure a sufficient cooling capability. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view illustrating an electronic apparatus according to an embodiment, which has been closed and set at a 0-degree attitude; 
         FIG. 2  is a plan view schematically illustrating the electronic apparatus illustrated in  FIG. 1 , which has been opened and set at a 180-degree attitude; 
         FIG. 3  is a plan view schematically illustrating the internal structure of the electronic apparatus illustrated in  FIG. 2 ; 
         FIG. 4A  is a side sectional view schematically illustrating the internal structure of the electronic apparatus at the 180-degree attitude; 
         FIG. 4B  is a side sectional view illustrating a state in the middle of rotation to the 0-degree attitude between chassis from the state illustrated in  FIG. 4A ; 
         FIG. 4C  is a side sectional view in a state in which the electronic apparatus illustrated in  FIG. 4A  is at the 0-degree attitude; 
         FIG. 5A  is a side sectional view schematically illustrating the internal structure of an electronic apparatus provided with a thermal rubber, which is a heat conductive member, according to a first modification example; 
         FIG. 5B  is a side sectional view schematically illustrating the electronic apparatus illustrated in  FIG. 5A  at a 90-degree attitude; 
         FIG. 5C  is a side sectional view schematically illustrating the electronic apparatus illustrated in  FIG. 5A  at the 0-degree attitude; and 
         FIG. 6  is a side sectional view schematically illustrating the internal structure of an electronic apparatus provided with a thermal sponge, which is a heat conductive member according to a second modification example. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The following will describe in detail preferred embodiments of the electronic apparatus according to the present invention with reference to the accompanying drawings. 
       FIG. 1  is a perspective view illustrating an electronic apparatus  10  according to an embodiment, which has been closed and set at a 0-degree attitude.  FIG. 2  is a plan view schematically illustrating the electronic apparatus  10  illustrated in  FIG. 1 , which has been opened and set at a 180-degree attitude.  FIG. 3  is a plan view schematically illustrating the internal structure of the electronic apparatus  10  illustrated in  FIG. 2 . 
     As illustrated in  FIG. 1  to  FIG. 3 , the electronic apparatus  10  includes a first chassis  12 A and a second chassis  12 B, a hinge device  14 , and a display  16 . The electronic apparatus  10  of the present embodiment exemplifies a tablet PC or a laptop PC that can be folded like a book. The electronic apparatus  10  may be a mobile phone, a smartphone, a portable game machine, or the like. 
     The chassis  12 A and  12 B are placed adjacent to each other. Each of the chassis  12 A and  12 B is placed adjacent to the other. Each of the chassis  12 A and  12 B is formed of, for example, a rectangular plate-like member having side walls formed upright on three sides other than the side (an adjacent end portion  12 Aa or  12 Ba) connected by the hinge device  14 . Each of the chassis  12 A and  12 B is composed of a metal plate of, for example, stainless steel, magnesium, aluminum, or the like, or a fiber reinforced resin plate or the like containing a reinforcing fiber such as a carbon fiber. The hinge device  14  connects the chassis  12 A and  12 B in a relatively rotatable manner. The hinge device  14  also functions as a spine member that hides the gap between the adjacent end portions  12 Aa and  12 Ba formed at the 0-degree attitude illustrated in  FIG. 1 . The display  16  extends across the chassis  12 A and  12 B. 
     As illustrated in  FIG. 3 , the first chassis  12 A includes a motherboard  17  on which various semiconductor chips such as a CPU (Central Processing Unit)  17   a,  a communication module  17   b,  and an SSD (Solid State Drive)  17   c  are mounted. The CPU  17   a  performs calculations related to the main control and processing of the electronic apparatus  10 . The CPU  17   a  is the largest heat generating element among the electronic components mounted in the electronic apparatus  10 . The communication module  17   b  is a device that performs information processing of wireless communication transmitted and received via antennas mounted in the chassis  12 A and  12 B, and corresponds to, for example, a wireless WAN and a fifth-generation mobile communication system. The SSD  17   c  is a storage device using a semiconductor memory. The communication module  17   b  and the SSD  17   c  are heat generating elements having a second largest amount of heat generation following that of the CPU  17   a.    
     The second chassis  12 B includes, for example, a battery device  18 . The amount of heat generated by the battery device  18  is smaller than that of the CPU  17   a  or the like. Therefore, in the electronic apparatus  10 , the amount of heat generated in the first chassis  12 A is larger than the amount of heat generated in the second chassis  12 B. 
     Hereinafter, the electronic apparatus  10  will be described by referring to the direction in which the chassis  12 A and  12 B are arranged as an X direction, a direction along the adjacent end portions  12 Aa and  12 Ba orthogonal to the X direction as a Y direction, and a thickness direction of the chassis  12 A and  12 B as a Z direction. Further, the rotational angle attitude between the chassis  12 A and  12 B will be explained by referring to a state in which the two are stacked as a 0-degree attitude (refer to  FIG. 1  and  FIG. 4C ), and a state in which the two are arranged on left and right as a 180-degree attitude (refer to  FIG. 4A ). For an attitude between 0 degree and 180 degrees, the degrees therebetween will be divided and referred to as appropriate, and the attitude illustrated in, for example,  FIG. 4B  will be referred to as a 45-degree attitude. 
       FIG. 4A  is a side sectional view schematically illustrating the internal structure of the electronic apparatus  10  at the 180-degree attitude.  FIG. 4B  is a side sectional view illustrating a state midway through the rotation to the 0-degree attitude between the chassis  12 A and  12 B from the state illustrated in  FIG. 4A .  FIG. 4C  is a side sectional view in a state in which the electronic apparatus  10  illustrated in  FIG. 4A  is at the 0-degree attitude. 
     As illustrated in  FIG. 4A  to  FIG. 4C , the chassis  12 A and  12 B are connected by the hinge device  14  in a relatively rotatable manner between the 0-degree attitude (refer also to  FIG. 1 ) and the 180-degree attitude (refer also to  FIG. 2 ). 
     At the 0-degree attitude illustrated in  FIG. 4C , the chassis  12 A and  12 B are stacked so as to overlap each other in a surface normal direction. At this time, the display  16  is placed such that a region RA on the first chassis  12 A side and a region RB on the second chassis  12 B side face each other, and a fold region R 1 , which is a boundary region between the regions RA and RB, is bent into an arc shape. At the 180-degree attitude illustrated in  FIG. 4A , the chassis  12 A and  12 B are arranged side by side in a direction perpendicular to the surface normal direction. At this time, in the display  16 , the regions RA, RB and the fold region R 1  are placed side by side on an XY plane, and form a single flat plate shape as a whole. 
     As illustrated in  FIG. 4A  to  FIG. 4C , the display  16  has a structure in which, for example, a sheet-like member  22  is attached to the back surface of a display panel  20 . In the display  16 , the region RA is relatively fixed with respect to the first chassis  12 A, and the region RB is relatively fixed with respect to the second chassis  12 B. 
     Specifically, a back surface  16   a  of the region RA is supported by a first plate  24 A and a first support plate  27 A, and fixed to the first chassis  12 A through the intermediary of the first plate  24 A. The back surface  16   a  of the region RB is supported by a second plate  24 B and a second support plate  27 B, and fixed to the second chassis  12 B through the intermediary of the second plate  24 B. The plates  24 A and  24 B are plates formed of a fiber-reinforced resin or a metal, and support most of the display  16  on both sides of the hinge device  14  (refer to  FIG. 3 ). The plates  24 A and  24 B are fixed to the chassis  12 A and  12 B with screws or the like. The support plates  27 A and  27 B are components of the hinge device  14 . 
     The fold region R 1  is relatively movable with respect to the chassis  12 A and  12 B. At the 180-degree attitude, the back surface  16   a  of the fold region R 1  is supported by a hinge main body  26  and the support plates  27 A and  27 B (refer to  FIG. 4A ). At the 0-degree attitude, the fold region R 1  is bent into an arc shape, and a part of the back surface  16   a  is supported by the support plates  27 A and  27 B, and most of the back surface  16   a  separates from the hinge device  14  (refer to  FIG. 4C ). 
     As illustrated in  FIG. 3  to  FIG. 4C , the hinge device  14  of the present embodiment has the hinge main body  26 , the first support plate  27 A, and the second support plate  27 B. 
     The hinge main body  26  is provided, being positioned across the adjacent end portions  12 Aa and  12 Ba of the chassis  12 A and  12 B (refer to  FIG. 4A ), and extends along the adjacent end portions  12 Aa and  12 Ba in the Y direction over substantially the full length (refer to  FIG. 1  and  FIG. 3 ). The hinge main body  26  is a block-like component made of a metal such as aluminum. The hinge main body  26  supports two hinge shafts  14 A and  14 B, which are aligned in the X direction at the 180-degree attitude. The hinge shaft  14 A is connected to the first chassis  12 A through the intermediary of a link member or the like. The hinge shaft  14 B is connected to the second chassis  12 B through the intermediary of a link member or the like. Housed inside the hinge main body  26  are a gear mechanism for synchronizing the rotational movements between the chassis  12 A and  12 B, a torque mechanism for applying a predetermined rotational torque to the rotational movements between the chassis  12 A and  12 B, and the like. The outer surface of the hinge main body  26  is covered with a cover material  26   a.    
     At the 180-degree attitude illustrated in  FIG. 4A , the hinge main body  26  is housed in the chassis  12 A and  12 B, and stretches, in the X direction, across the adjacent end portions  12 Aa and  12 Ba in close proximity to or in contact with each other. At the 0-degree attitude illustrated in  FIG. 4C , the hinge main body  26  is placed so as to close the gap between the adjacent end portions  12 Aa and  12 Ba that are widely separated from each other, and serves as the spine of the electronic apparatus  10  folded like a book. At this time, the cover material  26   a  is exposed to the outermost surface to prevent the appearance design of the folded electronic apparatus  10  from being deteriorated (refer to  FIG. 1 ). 
     The first support plate  27 A is provided on an inner surface  12 Ab side of the first chassis  12 A and extends along the adjacent end portion  12 Aa in the Y direction over substantially the full length. The first support plate  27 A is a plate-like member made of a metal such as aluminum. The first support plate  27 A has, for example, a plate thickness of approximately 0.5 to 3 mm, a total length (Y direction) of approximately 150 to 300 mm, and a total width (X direction) of approximately 20 to 100 mm. One end portion of the first support plate  27 A in the width direction (X direction) is rotatably connected to the hinge main body  26  by using a rotation shaft  28 A. The other end portion of the first support plate  27 A in the width direction is connected so as to be relatively movable with respect to the first chassis  12 A. Specifically, the other end portion of the support plate  27 A is connected to the first plate  24 A fixed to the first chassis  12 A through a link  30 A. The link  30 A is a rod-like member extending in the X direction. One end portion of the link  30 A is, for example, connected to the first support plate  27 A by a rotation shaft in a relatively rotatable manner, and the other end portion thereof is connected with the first plate  24 A so as to be relatively rotatable and also relatively movable in the X direction. For example, four links  30 A are installed in the Y direction (refer to  FIG. 3 ). 
     The second support plate  27 B is provided on an inner surface  12 Bb side of the second chassis  12 B and extends along the adjacent end portion  12 Ba in the Y direction over substantially the full length. The second support plate  27 B is a plate-like member made of a metal such as aluminum. The size of the second support plate  27 B may be the same as that of the first support plate  27 A. The second support plate  27 B is supported by the second chassis  12 B side such that the second support plate  27 B is attached so as to be laterally symmetrical with the first support plate  27 A, and therefore, a detailed description thereof will be omitted. In other words, a rotation shaft  28 B similar to the rotation shaft  28 A and a link  30 B similar to the link  30 A are connected to the second support plate  27 B. 
     The support plates  27 A and  27 B support the back surface  16   a  of the display  16  between the 0-degree attitude and the 180-degree attitude by front surfaces  27 Aa and  27 Ba. The support plates  27 A and  27 B relatively move with respect to the inner surfaces  12 Ab and  12 Bb of the chassis  12 A and  12 B in the X direction and a Z direction according to the rotational movement between the chassis  12 A and  12 B. Consequently, the support plates  27 A and  27 B correct the fold region R 1  of the display  16  into an appropriate shape (a linear shape or a curved shape) according to a rotation angle. 
     As illustrated in  FIG. 4A  to  FIG. 4C , the electronic apparatus  10  includes a graphite sheet  32  as a flexible heat conductive member in the first chassis  12 A. The graphite sheet  32  is formed by processing graphite (black lead), which is an allotrope of carbon, into a sheet shape, and has high thermal conductivity. The graphite sheet  32  is a thin and flexible sheet having a plate thickness of, for example, approximately 10 μm to 1 mm. 
     As illustrated in  FIG. 4A , the graphite sheet  32  is placed between the first support plate  27 A and the first chassis  12 A in a curved attitude to thermally connect the two. As illustrated in  FIG. 3 , the graphite sheet  32  extends over substantially the full length of the first support plate  27 A in the Y direction. In the side view given in  FIG. 4A , the graphite sheet  32  has a first end portion  32   a  thereof on the upper side fixed to a back surface  27 Ab of the first support plate  27 A, and a second end portion  32   b  thereof on the lower side fixed to the inner surface  12 Ab of the first chassis  12 A. The end portions  32   a  and  32   b  are fixed to surfaces  27 Ab and  12 Ab by using, for example, a double-sided tape or an adhesive agent that has thermal conductivity. A central portion  32   c  between the end portions  32   a  and  32   b  is curved between the back surface  27 Ab and the inner surface  12 Ab in a movable manner. 
     A description will now be given of the operation for rotating the chassis  12 A and  12 B from the 180-degree attitude to the 0-degree attitude, and working effects at that time. 
     First, at the 180-degree attitude illustrated in  FIG. 4A , the plates  24 A and  24 B, the hinge main body  26 , and the support plates  27 A and  27 B are all arranged on the same XY plane, and all the surfaces are placed to be flush, thus forming a flat plate as a whole. The entire back surface  16   a  of the display  16  is supported on the flat plate, forming a single flat-plate-like large screen (refer also to  FIG. 2 ). A symbol  34  in  FIG. 2  denotes a bezel member, which is a member surrounding, like a frame, an inactive region in the peripheral portion of a front surface  16   b  of the display  16 . 
     Thus, at the 180-degree attitude, the electronic apparatus  10  functions as a tablet PC having a large screen. At this time, the CPU  17   a  generates a large amount of heat depending on the usage state of the electronic apparatus  10 . If this happens, the capability of the CPU  17   a  itself may deteriorate, or hot spots may occur on an outer surface  12 Ac of the first chassis  12 A. 
     Therefore, the electronic apparatus  10  includes the graphite sheet  32 , which thermally connects the first support plate  27 A and the first chassis  12 A (refer to  FIG. 4A ). Thus, when the heat from the CPU  17   a  is transferred to the first chassis  12 A, the heat is transferred to the first support plate  27 A through the graphite sheet  32 . The arrows indicated by the chain lines in  FIG. 4A  schematically illustrate the movement of the heat. 
     Here, the first support plate  27 A has a certain thickness and is composed of a metal plate (aluminum plate) elongated in the Y direction, so that the first support plate  27 A exhibits high thermal conductivity and a large heat capacity. For this reason, the first support plate  27 A functions as a thermal storage that stores the heat transferred from the graphite sheet  32 , and at the same time, functions also as a heat spreader that dissipates the heat while diffusing the heat. In addition, the first support plate  27 A is mechanically connected to the hinge main body  26  also made of a metal and the second support plate  27 B. Therefore, the heat received by the first support plate  27 A is further transferred also to the hinge main body  26  and the second support plate  27 B, where the heat is stored also, and at the same time, the heat is diffused and dissipated. At this time, in the electronic apparatus  10  of the present embodiment, the temperature inside the second chassis  12 B is lower than that inside the first chassis  12 A, thus enabling efficient heat dissipation. This leads to temperature balance between the left and right chassis  12 A and  12 B, making it possible to suppress the generation of hot spots more reliably. 
     As described above, the electronic apparatus  10  of the present embodiment includes the hinge device  14  composed of a metal component having a large heat capacity, and a heat conductive member (graphite sheet  32 ) thermally connecting the heat receiving member (the first chassis  12 A), which receives heat from the CPU  17   a,  and the hinge device  14 . Thus, in the electronic apparatus  10 , the entire hinge device  14  functions as a thermal storage and a heat spreader, so that a sufficient cooling capacity is obtained without separately installing cooling devices in the chassis  12 A and  12 B. Instead of the graphite sheet  32 , a metal sheet of copper, aluminum, or the like may be used. 
     The electronic apparatus  10  may be provided with a separate cooling device  36  for cooling the CPU  17   a  (refer to the cooling device  36  indicated by the two-dot chain line in  FIG. 4A ). Examples of the cooling device  36  include a heat spreader such as a copper plate or an aluminum plate, a vapor chamber, and the like, as well as cooling fins, a blower fan, and the like connected thereto. If a configuration that includes the cooling device  36  is adopted, then the second end portion  32   b  of the graphite sheet  32  may be connected to a heat receiving member (e.g., a heat spreader or a vapor chamber) constituting the cooling device  36 . This makes it possible to reinforce the cooling capacity of the cooling device  36  by the hinge device  14 . 
     The electronic apparatus  10  of the present embodiment may further include a sheet-like member  38  and a graphite sheet  40  indicated by the two-dot chain lines in  FIG. 4A . 
     The sheet-like member  38  is a thin sheet formed of a material having high thermal conductivity. The sheet-like member  38  is, for example, a graphite sheet or a metal sheet of copper, aluminum, or the like. The sheet-like member  38  extends from the back surface  27 Ab of the first support plate  27 A to a back surface  27 Bb of the second support plate  27 B through between the hinge main body  26  and the cover material  26   a.  The sheet-like member  38  should also extend in the Y direction over substantially the full length of the hinge device  14 . Thus, the heat transferred from the graphite sheet  32  to the first support plate  27 A is further efficiently transferred by the sheet-like member  38  to the hinge main body  26  and the second support plate  27 B. 
     The graphite sheet  40  has the same properties as the graphite sheet  32 , and is connected between the second support plate  27 B and the second chassis  12 B in the same mounting state as the graphite sheet  32 . Providing the electronic apparatus  10  with the graphite sheet  40  makes it possible to dissipate, to the second chassis  12 B, the heat transferred to the second support plate  27 B. 
     A description will now be given of a case where the chassis  12 A and  12 B are rotated from the 180-degree attitude toward the 0-degree attitude. 
     In this case, as illustrated in  FIG. 4B  and  FIG. 4C , the support plates  27 A and  27 B relatively pivot with respect to the chassis  12 A and  12 B, and relatively move in the X direction and the Z direction with respect to the chassis  12 A and  12 B. The fold region R 1  of the display  16  is folded while being appropriately pressed by the support plates  27 A and  27 B that move as described above. As a result, the fold region R 1  is formed substantially like a bell as illustrated in  FIG. 4C  at the 0-degree attitude. In other words, as illustrated in  FIG. 1  and  FIG. 4C , the electronic apparatus  10  of the present embodiment is in a folded state with high aesthetic quality, in which the chassis  12 A and  12 B are substantially parallel to each other at the 0-degree attitude. On the other hand, the fold region R 1  of the display  16  is not bent and has a bell shape curved with a desired curvature, thus suppressing damage to the display  16 . 
     As described above, the graphite sheet  32  has flexibility, and the central portion  32   c  has the curved shape. Consequently, during the movement toward the 0-degree attitude, the graphite sheet  32  smoothly follows the relative movement between the first support plate  27 A and the first chassis  12 A (refer to  FIG. 4B  and  FIG. 4C ). Thus, damage to the graphite sheet  32  or the displacement of the end portions  32   a  and  32   b  is suppressed during the rotation movement between the chassis  12 A and  12 B. As a result, the graphite sheet  32  can always secure the state of thermal connection between the first support plate  27 A and the first chassis  12 A. Consequently, when, for example, the angle between the chassis  12 A and  12 B is set to approximately 130 degrees to 90 degrees to use the electronic apparatus  10  in the same manner as a typical laptop PC, the hinge device  14  functions as a cooling device. Further, when, for example, images are being output to an external display from the electronic apparatus  10  set at the 0-degree attitude, the hinge device  14  functions as a cooling device. 
       FIG. 5A ,  FIG. 5B , and  FIG. 5C  are side sectional views schematically illustrating the internal structure of an electronic apparatus  10  provided with a thermal rubber  42 , which is a heat conductive member, according to a first modification example.  FIG. 5A ,  FIG. 5B , and  FIG. 5C  illustrate a 180-degree attitude, a 90-degree attitude, and a 0-degree attitude, respectively. 
     As illustrated in  FIG. 5A  to  FIG. 5C , the thermal rubber  42  is a component that replaces the graphite sheet  32  illustrated in  FIG. 4A  to  FIG. 4C . The thermal rubber  42  is a rubber material having flexibility and high thermal conductivity. The thermal rubber  42  has an upper surface  42   a  thereof fixed to a back surface  27 Ab of a first support plate  27 A by a double-sided tape or the like, and a lower surface  42   b  thereof fixed to an inner surface  12 Ab of a first chassis  12 A by a double-sided tape or the like. 
     The thermal rubber  42  flexibly collapses or expands in response to the relative movement of the first support plate  27 A with respect to the first chassis  12 A. Thus, also in the configuration using the above-described thermal rubber  42 , the thermal connection between the first support plate  27 A and a heat receiving member such as the first chassis  12 A can be maintained while flexibly following the rotational movement between the chassis  12 A and  12 B, as in the configuration using the graphite sheet  32 . 
       FIG. 6  is a side sectional view schematically illustrating the internal structure of an electronic apparatus  10  provided with a thermal sponge  44 , which is a heat conductive member, according to a second modification example.  FIG. 6  illustrates a 180-degree attitude. 
     As illustrated in  FIG. 6 , the thermal sponge  44  is a component that replaces the graphite sheet  32  illustrated in  FIG. 4A  to  FIG. 4C  or the thermal rubber  42  illustrated in  FIG. 5A  to  FIG. 5C . The thermal sponge  44  is a member having a structure in which a thin and flexible heat conductive sheet  44   b  is wrapped around the outer peripheral surface of a flexible sponge material  44   a.  Consequently, the thermal sponge  44  has flexibility as a whole. An upper surface  44   c  of the thermal sponge  44  is fixed to a back surface  27 Ab of a first support plate  27 A with a double-sided tape or the like, and a lower surface  44   d  is fixed to an inner surface  12 Ab of a first chassis  12 A with a double-sided tape or the like. A heat conductive sheet  44   b  is, for example, a graphite sheet or a metal sheet of copper, aluminum, or the like. The heat conductive sheet  44   b  has high thermal conductivity. Therefore, the thermal sponge  44  has high thermal conductivity on the outer surface regardless of the thermal conductivity of the sponge material  44   a  inside. 
     The thermal sponge  44  flexibly collapses or expands in response to the relative movement of the first support plate  27 A with respect to the first chassis  12 A. Thus, also in a configuration using the above-described thermal sponge  44 , the thermal connection between the first support plate  27 A and a heat receiving member such as the first chassis  12 A can be maintained while flexibly following the rotational movement between the chassis  12 A and  12 B, as in the configuration using the thermal rubber  42  or the like. 
     The present invention is not limited to the embodiments described above, and can of course be freely modified without departing from the gist of the present invention. 
     In the above, the configuration in which the heat generating elements (the CPU  17   a  and the like) are mounted in the first chassis  12 A has been exemplified. However, a heating element with a large amount of heat generation may be mounted also in the second chassis  12 B. In this case, a heat conductive member such as the graphite sheet  32  should be provided in both the chassis  12 A and  12 B, or in whichever chassis has a larger amount of heat generation. 
     Although the electronic apparatus  10  that can be folded in half like a book has been exemplified in the above, the present invention can be applied to various configurations, other than a configuration in which chassis having the same shape are folded in half, such as a double-door configuration in which small chassis are foldably connected to the left and right edges of a large chassis, an S-shaped folding configuration in which chassis having different folding directions are connected to the left and right edges of a single chassis, and a J-shaped folding configuration in which a small chassis is foldably connected to one of the left and right edges of a large chassis. The number of chassis to be connected may be four or more.