JP2009193350A - Electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic device provided with a heat-dissipation mechanism capable of efficiently diffusing heat generated from an electronic component. <P>SOLUTION: A substrate 21 loaded with an electronic component, being a heat source, such as a CPU 22 is stored inside a base part 10 of an electronic device. The CPU 22 is attached with a heat sink 23 while the heat sink 23 is attached with an electric fan 24 and a bimetal 31. A keyboard 11 is provided to the upper side of the base part 10 while heat-dissipation plates 25, 26 are arranged under the keyboard 11 and at the bottom part of a casing, respectively. Bimetals 31, 32 are respectively arranged between the heat sink 23 and the heat-dissipation plate 25 and between the substrate 21 and the heat-dissipation plate 26. When a temperature inside the base part 10 rises, the bimetals 31, 32 come into contact with the heat-dissipation plates 25, 26 so as to diffuse heat generated in the CPU 22 to the outside of the casing via the heat-dissipation plates 25, 26. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic device including a heat dissipation mechanism that discharges heat generated from an electronic component to the outside of the housing, and more particularly, to an electronic device having an electronic component whose calorific value changes depending on the situation.

  In recent years, electronic devices such as computers have been rapidly improved in performance. High performance of computers is largely due to high speed of semiconductor devices (LSI: Large Scale Integration) such as CPU (Central Processing Unit) and chipsets. In addition, space-saving electronic devices such as notebook personal computers (hereinafter referred to as notebook PCs) are required to be further reduced in size and thickness with higher performance.

  In general, a semiconductor device such as a CPU increases in calorific value as performance increases. A large amount of heat is also generated from a hard disk device used in a computer. Therefore, it can be said that recent computers have a plurality of heat sources in the housing. On the other hand, when the temperature of the semiconductor device exceeds a certain level, thermal runaway occurs, causing malfunction or failure. For this reason, it is necessary to dissipate heat generated in a semiconductor device, a hard disk device, or the like to the outside of the casing and maintain the inside of the casing at a certain temperature or lower.

  In order to efficiently dissipate heat generated in the semiconductor device to the outside of the housing, a heat sink is usually attached to the semiconductor device such as a CPU and a chip set. In addition, an electric fan is provided in the housing, external low-temperature air is taken into the housing, and warm air in the housing is discharged to the outside. Furthermore, the notebook PC adopts a structure in which heat generated in the CPU or hard disk device is transmitted to the casing through a heat transfer material and is radiated from the casing.

As prior art which seems to be related to this invention, there exist some which were described in patent documents 1-4. Patent Documents 1 and 2 describe notebook PCs having a mechanism for transferring heat generated by a CPU or the like to the back side of a liquid crystal display unit by a coolant and radiating heat from the back side of the display unit. Patent Document 3 describes an electronic device having a mechanism for transferring heat generated by a heating element (CPU) to a heat radiating plate disposed under a keyboard via a heat transfer material and radiating heat from the heat radiating plate. ing. Furthermore, Patent Document 4 describes an information processing apparatus including a mechanism that switches between forced cooling by an electric fan and natural cooling according to the amount of heat generated by a heating element (CPU).
JP 2002-182797 A JP 2006-173481 A JP 2001-142574 A WO2003 / 067949

  As described above, in the conventional notebook PC, heat generated by the CPU or the like is transmitted to the casing through the heat transfer material, and is radiated from the casing. However, in such a method, since the heat source (CPU or the like) and the casing are always thermally connected by the heat transfer material, the temperature of the casing rises even when the load on the CPU or the like is small. Since heat transfer efficiency is related to the temperature difference between the heat source and the heat sink, if the temperature of the housing is high when the load is small, heat is efficiently transferred from the heat source to the heat sink when the load increases. Can not do it. Moreover, when the temperature of the part which a human body always contacts like a palm rest becomes high, it becomes a cause which gives a user discomfort. The methods described in Patent Documents 1 to 3 also have the same problem as described above because the heat source and the casing are basically thermally connected to each other by the heat transfer material.

  Patent Document 4 describes that the electric fan is controlled in accordance with the heat generation amount. However, in recent small and lightweight notebook PCs, various parts are arranged in a high density in the casing, so there are portions where air does not flow easily, and heat generated by a heat source can be generated only by cooling with an electric fan. It may not be able to dissipate sufficiently.

  Accordingly, an object of the present invention is to provide an electronic device including a heat dissipation mechanism that can efficiently dissipate heat generated from an electronic component.

  According to one aspect of the present invention, a housing provided with a heat sink, an electronic component housed in the housing, and the electronic component and the heat sink are disposed between the electronic component and the heat sink. Accordingly, an electronic device having a switching member that thermally connects or blocks between the electronic component and the heat dissipation plate is provided.

  The electronic device according to the present invention includes a switching member that thermally connects or blocks between an electronic component serving as a heat source and a heat radiating plate in accordance with the temperature in the housing. When the temperature in the housing is low, an increase in the temperature of the housing can be suppressed by thermally blocking between the electronic component and the heat sink by the switching member. When the temperature inside the housing becomes high, the switching member thermally connects the electronic component and the heat sink. The heat generated from the electronic component is transmitted to the heat sink and the heat sink is outside the housing. To be discharged. Thereby, an excessive temperature rise of the electronic component is prevented, and occurrence of malfunction or failure is avoided.

  For example, a bimetal can be used as the switching member. The bimetal deforms according to the temperature, so if the temperature is low, the bimetal and the heat sink do not contact each other, and if the temperature exceeds a certain temperature, the bimetal and the heat sink can be used as a switching member. it can. However, the switching member is not limited to the bimetal, and depends on the output of the temperature sensor, the operation type heat transfer plate, the heat transfer plate receiving portion having a surface that can contact the heat transfer plate, and the temperature sensor. And a heat transfer plate driving unit that drives the heat transfer plate.

  A plurality of heat radiating plates and a plurality of switching members having different operating temperatures may be provided in the housing. For example, when the present invention is applied to a notebook PC, heat sinks are disposed in places where it is difficult for the user to feel uncomfortable even when the temperature rises, such as under the keyboard or the back side of the display unit. And a switching member having a low operating temperature is disposed between the electronic component serving as a heat source. Moreover, a heat sink is arrange | positioned in the place which gives a user a discomfort when temperature becomes high like a palm rest, and the switching member with a high operating temperature is arrange | positioned between those heat sinks and the electronic component used as a heat source. With this configuration, the heat dissipation area (the total area of the heat sink thermally connected to the electronic component) changes according to the amount of heat generated by the electronic component, and the heat generated from the electronic component is efficiently In addition, the temperature inside the casing can be kept low even if the electronic component generates a large amount of heat. Moreover, when temperature rises like a palm rest, the temperature rise of the site | part which gives a user discomfort can be suppressed.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is an external view showing an example of an electronic device (notebook type PC) according to the first embodiment of the present invention, and FIGS. 2 to 4 are schematic views showing the inside of the electronic device. 2 and 4 show the inside of the base portion of the electronic apparatus, and FIG. 3 shows a connection portion between the base portion and the display portion.

  As shown in FIGS. 1 and 3, the electronic device (notebook PC) according to the present embodiment can be freely opened and closed via a base part (base part housing) 10 and a hinge (hinge) to the base part 10. The display unit (display unit housing) 40 is attached. The display unit 40 is provided with a liquid crystal display panel 41 that displays characters, videos, and the like based on signals sent from the base unit 10.

  A keyboard 11, a touch pad (pointing device) 12, a palm rest 13, and the like are provided on the upper side of the base portion 10. The keyboard 11 is mainly used for inputting characters and the touch pad 12 is used for moving a cursor. The palm rest 13 is a portion on which a palm is placed when the keyboard 11 is operated, and is provided to facilitate the operation of the keyboard 11.

  Further, as shown in FIG. 2, a wiring board (main board) 21 on which electronic components such as a CPU 22 and a chip set (not shown) are mounted, and a hard disk device (not shown) are installed in the base unit 10. And a power source (not shown) and the like are accommodated. The CPU 22, the chip set, the hard disk device, and the power source are all electronic components that generate heat during operation. Here, only the CPU 22 that generates a relatively large amount of heat is illustrated as an electronic component that serves as a heat source.

  A heat sink 23 is attached to the CPU 22 in order to remove heat from the CPU 22. In this embodiment, as the heat sink 23, a fin type (air-cooled) heat sink formed of a metal having excellent thermal conductivity such as aluminum (Al) or copper (Cu) is used. A heat exchanging heat sink that takes heat away from the heating element by circulating the fluid.

  A heat conductive paste is applied between the CPU 22 and the heat sink 23, and the heat generated from the CPU 22 is efficiently transferred to the heat sink 23 by filling the gap between the CPU 22 and the heat sink 23 with the heat conductive paste. be able to. As the heat conductive paste, for example, a thermal compound is used.

  The electric fan 24 is connected to the heat sink 23. The electric fan 24 is driven and controlled in accordance with the output of a sensor (not shown) that detects the temperature of the CPU 22, generates an air flow in the casing of the base unit 10, and discharges the heat in the casing to the outside. At the same time, cool air is introduced into the housing. The electric fan 24 may have a constant rotational speed, or may have a rotational speed that changes according to the temperature of the CPU 22.

  In the present embodiment, as shown in FIGS. 2 and 4, heat radiation plates 25, 26, and 28 are provided below the keyboard 11, below the casing bottom of the base portion 10, and below the palm rest 13, respectively. Further, a heat transfer plate 27 is disposed slightly apart from the heat dissipation plates 25 and 28 between the heat dissipation plate 25 under the keyboard 11 and the heat dissipation plate 28 under the palm rest 13. All of these heatsinks 25, 26, 28 and heat transfer plate 27 are made of a material having excellent thermal diffusivity or thermal conductivity in the planar direction, such as a graphite sheet.

  A bimetal 31 is disposed between the heat sink 23 and the heat sink 25 under the keyboard 11. Further, a bimetal 32 is disposed between the wiring board 21 and the heat sink 26 at the bottom of the housing, and between the heat sink 25 and the heat transfer plate 27 and between the heat transfer plate 27 and the heat sink 28. Bimetals 33 and 34 are respectively arranged in the.

  On the other hand, as shown in FIG. 3, a heat radiating plate 44 is provided on the back side of the display unit 40, and a heat transfer plate 43 is provided on the inner side of the display unit 40. The heat transfer plate 43 is thermally connected to the heat radiating plate 25 under the keyboard 11 via a thermal hinge (a hinge made of a material having excellent thermal conductivity) 42. A bimetal 45 is disposed between the heat transfer plate 43 and the heat radiating plate 44. The heat transfer plate 43 and the heat radiating plate 44 are both made of a material having excellent thermal diffusivity or thermal conductivity in the planar direction, such as a graphite sheet.

  FIG. 5 is a perspective view showing the bimetal 31. The other bimetals 32 to 34 and 45 have the same structure as the bimetal 31.

  As shown in FIG. 5, the bimetal 31 is bent so that the cross section has a “Z” shape, and the length L is, for example, 50 mm. The bimetal 31 has a structure in which dissimilar metal plates having different coefficients of thermal expansion such as Cu—Ni—Mn / Cu / NiFe or Ni—Mn—Fe / Cu / NiFe are bonded together.

Each of the bimetals 31 to 34 and 45 used in this embodiment includes a Cu plate or a Cu alloy plate. Thus, the bimetal having a structure including the Cu plate or the Cu alloy plate on the high expansion side has an advantage of high thermal conductivity. For example, when the thickness of the Cu plate is 0.1 mm and the size of the bimetal is 50 mm (length) × 10 mm (width), the thermal resistance is 5 × 10 ⁻³ ° C./W. When the thickness of the Cu plate is 0.1 mm and the size of the bimetal is 10 mm (length) × 10 mm (width), the thermal resistance is 2.5 × 10 ⁻² ° C./W.

  When the temperature rises, the bimetal 31 comes into contact with the heat sink 25 (on state) as shown in FIG. 6 (b) from a state separated from the heat sink 25 (off state) as shown in FIG. 6 (a). Deforms (extends). Thereby, the bimetal 31 and the heat sink 25 are thermally connected. In addition, in order to reduce the thermal resistance between the bimetal 31 and the heat sink 25, a thin and flexible thermal sheet (not shown) may be disposed at the contact portion between the bimetal 31 and the heat sink 25. preferable.

  FIG. 7 is a diagram illustrating a processing flow of the heat dissipation mechanism of the electronic device according to the present embodiment. With reference to FIG. 7, the operation of the heat dissipation mechanism of the electronic device according to the present embodiment will be described.

  Here, it is assumed that the electric fan 24 operates when the temperature of the CPU 22 is equal to or higher than T1. The temperature at which the bimetal 31 attached to the upper surface of the heat sink 23 comes into contact with the heat radiating plate 25 and the temperature at which the bimetal 45 attached to the heat transfer plate 43 in the display unit 40 comes into contact with the heat radiating plate 44 are set. In both cases, T2 (T1 <T2) is assumed. Furthermore, the temperature when the bimetal 32 attached to the wiring board 21 contacts the heat radiating plate 26 at the bottom of the casing, and the temperature when the bimetal 33, 34 attached to the heat transfer plate 27 contacts the heat radiating plates 25, 28. The temperatures are all T3 (where T2 <T3).

  First, when the power is on (in the case of YES in step S11) and the temperature of the CPU 22 is lower than T1 (in the case of NO in step S12), that is, when the CPU 22 is hardly loaded (idling). The electric fan 24 is stopped. Further, the bimetals 31 to 34 and 45 are all in a state of being separated from the heat radiation plates 25, 26, 28, and 44. In this state, since the electric fan 24 is stopped, there is no noise generated from the electric fan 24 and power consumption is small. Moreover, the temperature of the housing is low.

 When a slight load is applied to the CPU 22 and the temperature of the CPU 22 is equal to or higher than T1 (YES in step S12), the electric fan 24 is operated (step S13). As a result, an air flow is generated in the casing of the base unit 10, and heat generated by the CPU 22 is discharged to the outside of the casing through the heat sink 23 and air. In this state, although there is some noise accompanying the operation of the electric fan 24, the temperature of the housing is relatively low.

  When a moderate load is applied to the CPU 22 and the amount of heat generated from the CPU 22 increases, the temperature in the casing of the base unit 10 rises. When the temperature in the housing reaches T2 or more (in the case of YES at step S14), the bimetals 31 and 45 extend and come into contact with the heat sinks 25 and 44 (step S15). Thereby, heat is transmitted from the heat sink 23 to the heat radiating plate 25 under the keyboard 11 through the bimetal 31, and further, heat is applied to the heat radiating plate 44 on the back surface side of the display unit 40 through the thermal hinge 42, the heat radiating plate 43 and the bimetal 45. Is transmitted. Then, heat is dissipated into the air from the keyboard 11 and the back side of the display unit 40 (step S16). In this state, although the temperature of a part of the casing (the back side of the keyboard 11 and the display unit 40) slightly increases, the temperature of the palm rest 13 and the casing bottom remains relatively low.

  When a high load is applied to the CPU 22, the temperature in the housing of the base unit 10 further increases. When the temperature inside the casing becomes T3 or more (in the case of YES at step S17), the bimetal 32 expands and contacts the heat sink 26, and the bimetals 33 and 34 extend and contacts the heat sinks 25 and 28 (step) S18). Thereby, heat is transmitted to the heat radiating plates 26, 25, and 28 through the bimetals 32, 33, and 34, and the heat is also dissipated from the bottom of the casing 10 and the palm rest 13 (step S19). In this state, in addition to heat radiation by the electric fan 24, heat is also discharged from the keyboard 11, the back side of the display unit 40, the bottom of the casing, and the palm rest 13, so even if a large amount of heat is generated from the CPU 22, the CPU 22. And an excessive temperature rise inside the housing is avoided. In addition, the temperature of the palm rest 13 and the bottom of the housing rises, but the heat sinks 25, 26, 28, 44 and the heat transfer plates 28, 43 are formed of a graphite sheet having excellent thermal diffusibility or heat conductivity, And since the heat radiation area is wide with the keyboard 11, the back side of the display unit 40, the bottom of the casing, and the palm rest 13, a local temperature rise (heat spot) of the casing is avoided.

  Note that the process flow from step S11 to step S19 is repeated while the power is on, and the process ends when the power is turned off. If NO in step S12, step S14, or step S17, the process returns to step S11.

  Hereinafter, the result of examining the relationship between the load of the CPU and the temperature of each part after manufacturing the electronic device (notebook type PC) according to the present embodiment will be described in comparison with a comparative example.

  First, as an example, a notebook PC provided with the heat dissipation mechanism shown in FIGS. In this case, graphite sheets (SS020: manufactured by Otsuka Electric Co., Ltd.) having a thickness of 0.5 mm were used as the heat radiation plates 25, 26, 28, 44 and the heat transfer plates 27, 43. Further, as the bimetals 31 to 34, 45, high thermal conductive bimetals (made by NEOMAX) made of Ni-Mn-Fe / Cu / Ni-Fe were used. A flexible thermal sheet (Fermia 50α: manufactured by Otsuka Electric Co., Ltd.) was attached to the contact surfaces of these bimetals 31 to 34 and 45 with the heat sink.

  The temperature at which the bimetal 31 attached to the heat sink 23 contacts the heat sink 25 under the keyboard 11 is 40 ° C., and the temperature at which the bimetal 32 attached to the wiring board 21 contacts the heat sink 26 at the bottom of the housing is 58. The temperature when the bimetals 33 and 34 attached to the heat transfer plate 27 between the keyboard 11 and the palm rest 13 are in contact with the heat dissipation plates 25 and 28 is 58 ° C., and is attached to the heat transfer plate 43 in the display unit 40. The temperature at which the bimetal 45 comes into contact with the heat radiating plate 44 disposed on the back side of the display unit 40 is 40 ° C.

  A notebook PC provided with a heat dissipation mechanism according to this example was operated in an environment of room temperature (25 ° C.), and the temperature of each part during idling, low load, medium load, and high load was measured. The results are summarized in FIG. Note that MaxPower supplied from Intel Corporation was used as software to load the CPU. When no load is applied, idling is performed. When the CPU drive rate is 50%, the load is low. When the CPU drive rate is 75%, the load is medium. When the CPU drive rate is 100%, the load is high. It was.

  On the other hand, a general notebook PC was used as the electronic device of the comparative example, and the temperature of each part was measured by applying a high load (CPU drive rate of 100%) to the CPU under the same conditions. The notebook PC of this comparative example has a structure in which a heat source and a casing are always thermally connected by a heat transfer material. The measurement result of the temperature of each part at the time of high load in the comparative example is also shown in FIG.

  As shown in FIG. 8, in the notebook PC equipped with the heat dissipation mechanism according to the embodiment, the temperature of the casing (the back side of the display unit, the back of the keyboard, the palm rest, and the bottom of the casing) hardly increases at the time of low load as well as idling. It can be seen that the cooling performance is sufficient. Further, in the notebook type PC according to the embodiment, the heat radiation area increases from (display unit back side + keyboard back) to (display unit back side + keyboard back + palm rest + chassis bottom) as the load increases. I will do it. It can be seen from FIG. 8 that the temperature of each part of the housing gradually increases as the heat radiation area increases. However, the temperature of the CPU at the time of high load is kept relatively low at 65 ° C., and the temperature of each part is kept in an ergonomic preferable temperature range (40 ° C. or less).

  On the other hand, when the notebook PC of the comparative example is driven under a high load condition under the same conditions (room temperature), the CPU temperature is 65 ° C. as in the embodiment, but the palm rest temperature at which the palm contacts is 46 ° C. The temperature is as high as ° C, which may cause discomfort to the user. Further, it can be seen that the temperature at the bottom of the casing is as high as 50 ° C., and it is difficult to keep the temperature in a temperature range (40 ° C. or less) preferable for ergonomics.

  As described above, according to the present embodiment, the bimetals 31 to 34 and 45 are arranged between the electronic component serving as a heat source such as the CPU 22 and the heat radiating plate, and the heat radiating area according to the amount of heat generated from the electronic component. Therefore, it is possible to avoid malfunction and failure due to a temperature rise inside the housing, and to keep the temperature of the portion in contact with the human body low even when the amount of heat generation is large. Moreover, in this embodiment, since the bimetal is used for switching (on-off switching) of the thermal connection between the electronic component serving as a heat source and the heat radiating plate, an electronic circuit for thermal switching is provided. It is unnecessary and there is no increase in power consumption. Furthermore, since an electronic circuit is not used for thermal switching, there is no risk of an increase in the temperature in the housing due to a failure of the electronic circuit, and the reliability is high.

(Second Embodiment)
FIGS. 9A and 9B are schematic views showing an electronic apparatus (notebook type PC) provided with a heat dissipation mechanism according to the second embodiment of the present invention. Note that this embodiment differs from the first embodiment in that the mechanism for switching the thermal connection (on-off switching) between the heat source and the heat radiating plate is different, and the other configurations are basic. Since it is the same as that of 1st Embodiment, in FIG. 9 (a), (b), the same code | symbol is attached | subjected to the same thing as FIG. 2, and description of the overlapping part is abbreviate | omitted. 9A and 9B show only the thermal connection part between the wiring board 21 and the heat sink 26 at the bottom of the housing, the other thermal connection parts have the same structure. Have.

  In the present embodiment, a heat transfer plate 52 driven by a stepping motor (heat transfer plate driving unit) 51 is provided on the wiring board 21. The heat transfer plate 52 is thermally connected to the CPU 22 via the wiring board 21. A heat transfer plate receiving portion 53 is provided on the heat dissipating plate 26 disposed at the bottom of the casing of the base portion 10. The stepping motor 51 is driven based on the output of a temperature sensor (such as a thermistor) 54 that detects the temperature of the CPU 22.

  When the temperature of the CPU 22 is low, the heat transfer plate 52 is separated from the heat transfer plate receiving portion 53 as shown in FIG. When the temperature of the CPU 22 rises, the stepping motor 51 is driven according to the output of the temperature sensor 54, and the surface of the heat transfer plate 52 and the surface of the heat transfer plate receiving portion 53 come into contact as shown in FIG. . Thereby, the heat generated by the CPU 22 is transmitted to the heat radiating plate 26 via the wiring substrate 21, the heat transfer plate 52 and the heat transfer plate receiving portion 53, and is dissipated from the heat transfer plate 26 to the outside of the casing.

  Also in this embodiment, since the thermal connection between the electronic component and the heat sink is switched according to the amount of heat generated from the electronic component (CPU 22), the temperature rise inside the housing is the same as in the first embodiment. It is possible to avoid malfunctions and failures due to the above, and to keep the temperature of the portion in contact with the human body low even when the amount of heat generated is large.

  Hereinafter, various aspects of the present invention will be collectively described as supplementary notes.

(Appendix 1) a housing provided with a heat sink;
Electronic components housed in the housing;
A switching member disposed between the electronic component and the heat sink, and thermally connecting or blocking between the electronic component and the heat sink in accordance with a temperature in the housing. Electronic equipment.

  (Additional remark 2) The said switching member is comprised with bimetal, The electronic device of Additional remark 1 characterized by the above-mentioned.

  (Additional remark 3) The electronic device of Additional remark 2 characterized by the above-mentioned. The thermal sheet is affixed on the surface at the said heat sink side of the said bimetal.

  (Additional remark 4) The said heat sink is comprised including a graphite sheet, The electronic device of Additional remark 1 characterized by the above-mentioned.

  (Supplementary Note 5) The switching member includes a temperature sensor, an operating heat transfer plate, a heat transfer plate receiving portion having a surface with which the heat transfer plate can contact, and the heat transfer according to an output of the temperature sensor. The electronic apparatus according to appendix 1, wherein the electronic apparatus includes a heat transfer plate driving unit that drives the plate.

  (Supplementary Note 6) An electronic device having a heat sink for removing heat from the electronic component, wherein the switching member is attached to the heat sink.

(Additional remark 7) The said housing | casing is comprised by the base part housing | casing which accommodates the said electronic component, and the display part housing | casing which was provided with the display panel and was attached to the said base part housing | casing so that opening and closing was possible,
The base housing has a keyboard and a palm rest on which a palm is placed when operating the keyboard.
The heat sink is disposed on the lower side of the keyboard, the lower side of the palm rest, and the back side of the display unit housing, and the switching member is disposed between the electronic component and the lower heat sink of the keyboard, It is disposed between the heat sink on the lower side of the keyboard and the heat sink on the back side of the display unit, and between the heat sink on the lower side of the keyboard and the heat sink on the lower side of the palm rest, respectively. The electronic device according to appendix 1.

  (Additional remark 8) The operating temperature of the switching member arrange | positioned between the heat sink below the said keyboard and the heat sink below the said palm rest is between the said electronic component and the heat sink below the said keyboard. The operating temperature of the switching member disposed on the keyboard and the operating temperature of the switching member disposed between the heat sink on the lower side of the keyboard and the heat sink on the back surface of the display unit are higher 8. The electronic device according to 7.

  (Supplementary note 9) Further, the electronic component and a switching member disposed between the heat sink disposed at the bottom of the base unit housing and a switching member disposed at the bottom of the base unit housing are disposed. The operating temperature of the switching member disposed between the heat radiating plate and the operating heat of the switching member disposed between the electronic component and the lower heat radiating plate of the keyboard, The electronic device according to appendix 8, wherein the electronic device has a temperature higher than an operating temperature of a switching member between the heat radiating plate and the heat radiating plate on the back surface side of the display unit.

  (Supplementary note 10) The electronic device according to supplementary note 8, further comprising an electric fan that operates according to a temperature of the electronic component and exhausts air in the base portion to the outside.

FIG. 1 is an external view showing an example of an electronic device (notebook PC) according to the first embodiment of the present invention. FIG. 2 is a schematic diagram showing the inside of the electronic device, and shows the inside of the base housing. FIG. 3 is a schematic view showing the inside of the electronic device, and shows a connection portion between the base portion and the display portion. FIG. 4 is a schematic view showing the inside of the electronic device, and shows a heat radiating plate and a heat transfer plate arranged under the keyboard and palm rest. FIG. 5 is a perspective view showing a bimetal. FIGS. 6A and 6B are schematic diagrams showing the operation of the bimetal. FIG. 7 is a diagram illustrating a processing flow of the heat dissipation mechanism of the electronic device according to the present embodiment. FIG. 8 is a diagram showing the results of measuring the temperature of each part when the electronic device (notebook type PC) of the example and the comparative example is operated. FIGS. 9A and 9B are schematic views showing an electronic apparatus (notebook type PC) provided with a cooling system according to the second embodiment of the present invention.

Explanation of symbols

10 ... Base part,
11 ... Keyboard,
12 ... Touchpad,
13 ... Palm rest,
21 ... wiring board,
22 ... CPU,
23 ... heat sink,
24 ... Electric fan,
25, 26, 44 ... heat sink,
27, 43, 52 ... heat transfer plate,
31-34, 45 ... bimetal,
40 ... display section,
41 ... Liquid crystal display panel,
42 ... thermal hinge,
51 ... Stepping motor,
53. Heat transfer plate receiving part,
54 ... Temperature sensor.

Claims (5)

A housing provided with a heat sink;
Electronic components housed in the housing;
A switching member disposed between the electronic component and the heat sink, and thermally connecting or blocking between the electronic component and the heat sink in accordance with a temperature in the housing. Electronic equipment.   The electronic device according to claim 1, wherein the switching member is made of a bimetal. The housing includes a base housing that houses the electronic component, and a display housing that includes a display panel and is attached to the base housing so as to be freely opened and closed.
The base housing has a keyboard and a palm rest on which a palm is placed when operating the keyboard.
The heat sink is disposed on the lower side of the keyboard, the lower side of the palm rest, and the back side of the display unit housing, and the switching member is disposed between the electronic component and the lower heat sink of the keyboard, It is disposed between the heat sink on the lower side of the keyboard and the heat sink on the back side of the display unit, and between the heat sink on the lower side of the keyboard and the heat sink on the lower side of the palm rest, respectively. The electronic device according to claim 1.   The operating temperature of the switching member disposed between the lower heat sink of the keyboard and the lower heat sink of the palm rest is disposed between the electronic component and the lower heat sink of the keyboard. The operating temperature of the switching member and the operating temperature of the switching member disposed between the heat sink on the lower side of the keyboard and the heat sink on the back side of the display unit are higher than the operating temperature of the switching member. Electronic devices.   And a switching member disposed between the electronic component and a heat radiating plate disposed at the bottom of the base housing, and the heat radiating plate disposed at the bottom of the electronic component and the base housing. Operating temperature of the switching member disposed between the electronic component and the lower heat sink of the keyboard, and the lower heat sink of the keyboard and the keyboard The electronic device according to claim 4, wherein the electronic device has a temperature higher than an operating temperature of the switching member between the heat sink on the back side of the display unit.

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