JP2017041830A - Mobile information terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mobile information terminal which prevents a deteriorated function at the high exothermic of an exothermic body, with the expansion of a radiation area at the high exothermic of the exothermic body to thereby improve heat dissipation efficiency, while maintaining portability.SOLUTION: In a mobile information terminal 10 which radiates heat with a heat pipe 20, a heat reception part 21 disposed on one end side of the heat pipe is arranged adjacent to an exothermic body 12 inside a housing 11 of the mobile information terminal. A heat radiation part 22 disposed on another end side of the heat pipe 20 is extracted to the outside of the housing 11 through a slit 13 provided on the housing 11 of the mobile information terminal. The heat radiation part 22 extracted to the outside of the housing 11 is disposed in overlay with the rear face 11B of the housing in a deformable manner to the vertical direction of the rear face 11B. On the heat radiation part 22 overlaid with the rear face 11B, there is arranged a temperature deformation member 23 which deforms, at a high temperature, the heat radiation part 22 in a manner to be apart from the rear face 11B, so that the radiation area of the heat radiation part 22 is increased at the high exothermic of the exothermic body 12 to increase heat dissipation efficiency.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a portable information terminal.

  In portable information terminals such as smartphones (hereinafter sometimes referred to as portable terminals), it is necessary to maintain both portability and to dissipate heat to prevent the temperature rise of portable terminals due to built-in heating elements such as CPUs. is there. On the other hand, from the viewpoint of carrying a portable terminal, it is desirable that the terminal case size is small, and development of a portable terminal that is small and thin is underway.

  FIG. 1A to FIG. 1C show an example of a portable terminal 1 to which the present application is directed. As shown in FIG. 1A, the mobile terminal 1 of this example includes a display 3 and an earpiece 4 that display images on the front surface 2, and a camera 6 on the back surface 5. Although not shown, the bottom surface 7 is provided with a mouthpiece, a headphone terminal, a charging terminal, or the like.

  Such heat dissipation of the mobile terminal 1 is generally natural air cooling from the outer surface of the casing of the mobile terminal 1. However, if the user simultaneously executes a plurality of applications on the mobile terminal 1 as the mobile terminal 1 has higher functionality and higher performance, the heating element becomes hot depending on the operating environment and use conditions, and the generated heat is In some cases, heat cannot be sufficiently radiated from the outer surface of the portable terminal 1 and the portable terminal 1 becomes hot.

  As a method for preventing the casing of the mobile terminal 1 from becoming high temperature, there is currently a temperature control method for the mobile terminal shown in FIG. In the temperature control of the portable terminal, when the surface temperature TB of the portable terminal approaches the upper limit temperature TM, the application being executed is stopped, the function of the portable terminal is suppressed, the heat generation is suppressed, and the surface temperature TB is lowered. When TB falls, the application is resumed. In order to operate a terminal without suppressing the function of the mobile terminal even when the mobile terminal is subjected to a high load and high heat generation, it is essential to improve the heat dissipation efficiency from the casing of the mobile terminal.

Here, the heat dissipation amount Q when the casing of the mobile terminal is naturally air-cooled is given by the following formula 1.
Q = hS (T _ST −T _air ) (1)
However, the heat transfer coefficient h is a natural convection, S is the area of the radiating surface of the portable terminal, T _ST is the temperature of the radiating surface, T _air is the air temperature. Further, the heat transfer coefficient h increases as the temperature difference between the temperature of the heat radiating surface and the atmospheric temperature increases. From Equation 1, it can be seen that it is effective to increase the temperature difference between the surface temperature S and the temperature of the heat dissipation surface and the atmospheric temperature in order to increase the heat dissipation amount Q.

JP-A-2-304997

JP 2014-167776 A

JP 2013-069925 A

JP 2014-026341 A

  However, since the casing of the mobile terminal directly touches the user's skin, it is difficult to increase the temperature difference from the outside air temperature by increasing the temperature of the heat radiation surface from the viewpoint of ensuring the safety of the user. For this reason, in order to increase the heat dissipation efficiency, the heat dissipation surface is soaked in a temperature range where the user does not burn, the average temperature of the entire heat dissipation surface is increased, the temperature difference from the outside temperature is increased, and the heat dissipation area is increased. It is required to expand.

  A material with high thermal conductivity, for example, a metal plate such as a copper plate, a graphite sheet, or the like, is used for soaking the heat radiation surface of the portable terminal. However, since a metal plate such as a copper plate increases the terminal weight, there is a problem that becomes a factor that impairs portability. In addition, although the graphite sheet has a high thermal conductivity, the thickness of the graphite sheet is small, so that the amount of heat that can be diffused as a total amount is small, and there is a problem that the heat cannot be sufficiently spread during high heat generation. Furthermore, in order to expand the heat dissipation surface, fins or the like can be used, or a fan can be mounted. However, this method has a problem that the casing of the portable terminal is enlarged and the portability is impaired.

  The present invention maintains the portability, expands the heat radiation area when the heating element emits high heat and the casing becomes high temperature, improves the heat radiation efficiency, and prevents the deterioration of the function of the heating element during high heat generation. An object is to provide a portable information terminal.

  In one aspect, the portable information terminal includes a slit provided in a casing of the portable information terminal, a heat receiving portion on one end side, a heat radiating portion on the other end side, and a temperature deformation member disposed on the heat radiating portion, The heat receiving part is arranged close to the heating element inside the case, the heat radiating part is drawn out of the case through the slit and overlapped on the back of the case, and the temperature deformation member is applied with heat of a predetermined temperature or more. There is provided a portable information terminal including a flexible heat transport mechanism that is deformed when the heat dissipation portion is deformed in a direction away from the rear surface.

  As one aspect, while maintaining portability, it is possible to increase the heat dissipation area and improve the heat dissipation efficiency when the housing is hot, so there is no need to limit the application when the mobile information terminal is under heavy load. There is an effect that convenience is improved.

An example of the portable terminal which this application makes object is shown, (a) is a front view, (b) is a rear view, (c) is a perspective view. It is operation | movement explanatory drawing of the portable terminal which shows the temperature control method of the portable terminal until now. (A) is a top view of 1st Example of the heat pipe used for the portable terminal to disclose, (b) shows the structure of 1st Example of the housing | casing of the portable terminal which attaches the heat pipe shown to (a). A perspective view and (c) are sectional views showing the process of attaching the heat pipe shown in (a) to the case of the portable terminal shown in (b). 3A is a perspective view showing a state where the heat pipe shown in FIG. 3A is attached to the casing of the mobile terminal shown in FIG. 3B, and FIG. 3B is a mobile terminal shown in FIG. It is sectional drawing in the AA of. (A) is a perspective view showing a state in which the first embodiment of the heat pipe is attached to the disclosed portable terminal, and (b) is a perspective view showing a state in which the first embodiment of the heat pipe shown in (a) is deformed. FIG. 4C is a side view of the mobile terminal shown in FIG. (A) is explanatory drawing which shows 1st Example of the engagement structure of the front-end | tip part of the sheet-like member of a heat pipe, and the back surface of a portable terminal, (b) is 2nd Example of the housing | casing of the portable terminal to disclose. The perspective view which shows a structure, (c) is a fragmentary perspective view which shows 2nd Example of the engagement structure of the front-end | tip part of the sheet-like member of a heat pipe, and the back surface of a portable terminal. (A) is a side view showing deformation due to temperature of the bimetal used in the second embodiment of the heat pipe, (b) is a side view showing deformation due to temperature when the bimetal shown in (a) is turned upside down, (C) is a side view of a third embodiment of a heat pipe in which the bimetal shown in (a) and the bimetal shown in (b) are alternately incorporated, and (d) is a third view of the heat pipe shown in (c). It is a side view which shows the deformation | transformation by the temperature of an Example. (A) is the perspective view at the time of a deformation | transformation of the portable terminal to which 3rd Example of the disclosed heat pipe was attached, (b) is a plane which shows the deformation | transformation by the temperature of 3rd Example of the heat pipe shown to (a). FIG. (A) is a top view of 4th Example of the heat pipe to disclose, (b) is a perspective view of the portable terminal in which 4th Example of the heat pipe shown to (a) was integrated. (A) is a side view of a portable terminal showing a state before the heat pipe of the portable terminal to which the fifth embodiment of the disclosed heat pipe is attached is deformed by heat, and (b) is a fifth embodiment of the disclosed heat pipe. The side view of the portable terminal which shows the state which the heat pipe of the portable information terminal to which the example was attached deform | transformed with the heat | fever, (c) is a perspective view of the portable terminal shown to (b).

  Hereinafter, embodiments of the present application will be described in detail based on specific examples with reference to the accompanying drawings. Components that are the same as those of the portable terminal 1 of the comparative technique described in FIGS. Will be described. In addition, in the heat pipe described later, members such as a flow path inside the sheet-like member forming the heat pipe may not be visible from the outside depending on the resin material used for the housing, and should be indicated by a broken line. However, in order to make the explanation easy to understand, it is shown by a solid line. Further, members having the same function will be described with the same reference numerals.

  FIG. 3A shows a first embodiment of the heat pipe 20 when the heat pipe 20 is used as a heat transport mechanism used in the disclosed portable terminal. The heat pipe 20 of the present embodiment is formed of a resin sheet-like member 25, and is horizontally long and flexible. By making the sheet-like member 25 made of resin, the weight can be reduced as compared with the case where a metal plate having the same thickness is used. PET (polyethylene terephthalate) or the like can be used as the resin of the sheet-like member 25, and the density thereof is 1/8 for copper and 1 / for aluminum when compared with a metal having high thermal conductivity. It is about 2. Inside the sheet-like member 25, a flow path 24 through which a refrigerant flows is provided in a meandering state in the longitudinal direction of the heat pipe 20. The flow path 24 has a turn part 24T for sequentially connecting the ends of the straight part 24S adjacent to the straight part 24S and a connecting part 24C for connecting the straight parts 24S at both ends, and the flow path 24 has a loop shape. .

  A portion surrounded by a broken line in the vicinity of one end of the heat pipe 20 (right side in FIG. 3A) is a heat receiving portion 21 that takes heat away from the heating element, and is surrounded by a broken line in the vicinity of the other end. The portion is a heat radiating portion 22 that releases heat carried by the refrigerant. The heat receiving portion 21 is attached to the inside of the casing of the portable terminal so that the heating element 12 is close to the position indicated by the rectangular broken line described in the central portion of the heat receiving portion 21. Further, the heat radiating portion 22 is pulled out from the housing and attached to the back surface of the housing.

  In the portion of the heat radiating portion 22, a temperature deformation member 23 made of a shape memory alloy is provided along a flow path 24 that passes through the heat radiating portion 22. As long as the temperature deformation member 23 is a portion between the flow paths 24 located outside the turn portion 24T, the installation location is not particularly limited. In the present embodiment, a total of four temperature deforming members 23 are provided at a portion between both ends in the short direction of the sheet-like member 25 and the flow path 24 closest to the both ends. The disclosed temperature deformation member 23 is flat at normal temperature, and when the temperature of the heat radiating portion 22 of the heat pipe 20 reaches a predetermined temperature or more, the temperature deformation member 23 is deformed and curved in a direction perpendicular to the plane of the sheet-like member 25. The deformation of the temperature deformation member 23 will be described later.

  FIG. 3B shows the structure of the first embodiment of the casing 11 of the mobile terminal 1 in a state where the heat pipe 20 shown in FIG. 3A is not attached. A heating element 12 is built in the housing 11, and a slit 13 for inserting the heat pipe 20 shown in FIG. 3A is provided on the back surface 1 </ b> B of the housing 11. In the heat pipe 20 shown in FIG. 3A, as shown in FIG. 3C, the heat receiving portion 21 is close to the heating element 12 (for example, CPU) mounted on the circuit board 14 inside the housing 11. The other end is drawn out of the housing 11 through the slit 13. A liquid crystal display 15 is provided on the front surface 11F side of the housing 11. The heat radiating portion 22 drawn out of the housing 11 through the slit 13 is superimposed on the back surface 11B of the housing 11.

  FIG. 4A shows a state where the heat pipe 20 shown in FIG. 3A is attached to the back surface 11B of the casing 11 of the mobile terminal 1 shown in FIG. 3B. 4B shows a cross section taken along the line AA of the portable terminal 1 shown in FIG. 4A, and the heat radiating portion 22 of the heat pipe 20 described in FIG. A state where the body 11 is overlaid on the back surface 11B of the body 11 is shown. A portion of the heat radiating portion 22 of the heat pipe 20 is overlapped and attached in a close contact state at a position that does not overlap the camera 6 on the back surface 11B of the housing 11. Moreover, since the thickness of the sheet-like member 25 is as thin as about 1 mm, even if the heat radiating part 22 of the heat pipe 20 is overlapped and adhered to the back surface 11B of the housing 11, the portability is maintained, and the portable terminal 1 No sense of incongruity in use.

  FIG. 5A shows a state in which the first embodiment of the heat pipe 20 is attached to the portable terminal 1, but in order to make the operation of the heat radiating section 22 easy to understand, the heat radiating section 22 includes a heat pipe. Only the temperature deformation member 23 at 20 is shown. When the portable terminal 1 operates and the heating element 12 (see FIG. 5C) inside the housing 11 generates high heat, the refrigerant that has absorbed the heat H by the heat receiving unit 21 generates heat H to the heat radiating unit 22. Since it carries, the thermal radiation part 22 becomes high temperature. Then, in the first embodiment of the heat pipe 20, as shown in FIGS. 5B and 5C, the temperature deformation member 23 is deformed in a wave shape in a direction perpendicular to the back surface 11B, and the sheet-like member 25 is flexible. Therefore, the heat radiation part 22 is also deformed in a wave shape.

  When the heat radiating portion 22 is deformed in a wave shape, a heat radiating space SP is formed between the heat radiating portion 22 and the back surface 11B of the housing 11. As a result, the heat radiating area of the heat radiating part 22 is increased and the heat radiating efficiency is improved, so that the temperature of the housing 11 is lowered and the portable terminal 1 does not become hot as compared with the case where the heat radiating part 22 is not deformed. For this reason, even if the user simultaneously executes a plurality of applications on the portable terminal 1 and the heating element 12 reaches a high temperature, the generated heat is sufficiently dissipated from the outer surface of the housing 11. Can be executed simultaneously.

  When the heat radiating portion 22 is deformed in a wave shape, the leading end portion 25T of the sheet-like member 25 moves inward from the end portion of the back surface 11B of the housing 11 as shown in FIG. In this operation, the front end 25T of the sheet-like member 25 moves smoothly on the back surface 11B of the housing 11 and does not separate from the back surface 11B. An engagement mechanism is provided between 11B. FIG. 6A shows a first embodiment of the engagement structure 30 between the front end portion 25T of the sheet-like member 25 and the back surface 11B.

  The engagement structure 30 of the first embodiment is associated with a slide shaft 31 and a locking ball 32 protruding from three positions of the front end portion 25T of the sheet-like member 25, and a slide groove 33 provided on the back surface 11B. It is formed with a stop ball insertion hole 34. The locking ball 32 is provided at the tip of the slide shaft 31. The slide groove 33 has a width that allows the slide shaft 31 to move smoothly, and the locking ball insertion hole 34 has a size that allows the locking ball 32 to be inserted, and is provided at the inner end of the slide groove 33. ing. The length of the slide groove 33 is longer than the maximum length to which the tip end portion 25T of the sheet-like member 25 moves when the heat radiating portion 22 is deformed into a wave shape. Further, the depth of the slide groove 33 is shorter than the entire length of the slide shaft 31. The front end portion 25T of the sheet-like member 25 can be attached to the back surface 11B in a close contact state by inserting the locking ball 32 into the locking ball insertion hole 34 and moving the slide shaft 31 to the end of the slide groove 33. .

  FIG. 6B shows the structure of the second embodiment of the casing 11 of the mobile terminal 1 to be disclosed. The difference between the housing 11 of the second embodiment and the housing 11 of the first embodiment is that a recess 16 for receiving the sheet-like member 25 of the heat pipe 20 is provided on the back surface 11B of the housing 11. It is a point. If the depth of the recess 16 is formed to be approximately the same as the thickness of the sheet-like member 25, the sheet-like member 25 attached to the back surface 11B does not protrude from the back surface 11B. A slide groove 33 and a locking ball insertion hole 34 are provided at the end of the recess 16. Further, in the case 11 of the second embodiment, a slit 13 for inserting the heat pipe 20 is provided inside the recess 16. Since the operation when the heat pipe 20 is attached to the housing 11 of the second embodiment is the same as the operation when the heat pipe 20 is attached to the housing 11 of the first embodiment, its illustration and description Is omitted.

  FIG. 6C shows the relationship between the front end portion 25T of the sheet-like member 25 and the back surface 11B of the portable terminal 1 when the heat pipe 20 is attached to the housing 11 of the second embodiment shown in FIG. A second embodiment of the engagement structure 30 is shown. In the engagement structure 30 of the second embodiment, a slide shaft 31 including a locking ball 32 is provided on the side surface of the sheet-like member 25, and a locking ball insertion hole 34 through which the locking ball 32 is inserted and a slide. A slide groove 33 for sliding the shaft 31 is provided on the side wall 16 </ b> W of the recess 16. The operation of the tip 25T when the sheet-like member 25 is deformed in the engagement structure 30 of the second embodiment is the same as the operation of the tip 25T of the sheet-like member 25 in the engagement structure 30 of the first embodiment. Therefore, illustration and description thereof are omitted.

  In the embodiment described above, the temperature deformation member 23 made of a shape memory alloy has been described as the temperature deformation member 23. On the other hand, as the temperature deformation member 23, the heat pipe 20 of the second embodiment using a bimetal other than the shape memory alloy is possible. A bimetal is formed by laminating two kinds of thin metal plates having different thermal expansion coefficients into a single plate shape, and is bent by a temperature change. In order to deform the heat radiating portion 22 in a wave shape at the high temperature as in the case where the shape memory alloy is used, two types of bimetals having different bending directions may be used. As two types of bimetals, for example, as shown in FIG. 7A, the bimetal 23M deforms so that the upper side becomes convex at a predetermined temperature or higher, and the lower side becomes convex as shown in FIG. 7B. A bimetal 23V that is deformed so as to be formed may be used.

  And in the heat pipe 20 of 2nd Example, as shown in FIG.7 (c), two types of bimetal 23M and bimetal 23V are alternately provided to the heat radiating part 22 of the heat pipe 20 every other at predetermined intervals. It is attached. In order to make the explanation easy to understand, in FIG. 7C, two types of bimetal 23M and bimetal 23V are attached to the outside of the sheet-like member 25, but in actuality, they are provided inside the sheet-like member 25. Can do. The two types of bimetals 23M and bimetals 23V may be alternately attached to the position of the temperature deformation member 23 made of the shape memory alloy shown in FIG. When the temperature deformation member 23 is formed of the bimetal 23M and the bimetal 23V, as shown in FIG. 7D, the temperature deformation member 23 is made of a shape memory alloy. The sheet-like member 25 changes into a wave shape.

  FIG. 8 (a) is a view of the deformed shape of the mobile terminal 1 to which the third embodiment of the disclosed heat pipe 20 is attached, and FIG. 8 (b) is a view of FIG. 8 (a). The third embodiment of the heat pipe 20 shown in FIG. As shown in FIG. 8A, a band-shaped temperature deformation member 23 is used as the temperature deformation member 23 used in the heat pipe 20 of the third embodiment. In the third embodiment of the heat pipe 20, a shape memory alloy or bimetal 23 </ b> M that is bent and deformed in a large arch shape so that the upper side is convex at a high temperature can be used for the temperature deformation member 23.

  In the heat pipe 20 of the third embodiment, when the heat radiating portion 22 becomes high temperature, the temperature deforming member 23 is not deformed in a wave shape, and is deformed into an arch shape in which the upper side is convex over the entire back surface 1B of the mobile terminal 1. To do. That is, as shown in FIG. 8B, the heat radiating portion 22 is greatly curved so that one heat radiating space SP is formed between the heat radiating portion 22 and the back surface 11 </ b> B of the housing 11. Since the heat radiation area SP increases the heat radiation area of the heat radiation portion 22 and improves the heat radiation efficiency, the temperature of the casing 11 is lowered and the portable terminal 1 does not become hot as compared with the case where the heat radiation portion 22 is not deformed. For this reason, even if the user simultaneously executes a plurality of applications on the portable terminal 1 and the heating element becomes high temperature, the generated heat can be sufficiently dissipated from the outer surface of the housing and the heat radiating part of the heat pipe 20, The user can continuously execute multiple applications simultaneously.

  Next, an embodiment in which a bias spring is used in addition to the temperature deforming member for the heat radiating portion of the heat pipe will be described with reference to FIG. FIG. 9A shows a fourth embodiment of the heat pipe 20 to be disclosed, and has the same shape as the first embodiment of the heat pipe 20 described in FIG. Moreover, FIG.9 (b) shows the back surface 11B side of the housing | casing 11 of the portable terminal 1 to which the heat pipe 20 of 4th Example shown to Fig.9 (a) was attached. The heat pipe 20 of the fourth embodiment is different from the heat pipe 20 of the first embodiment in that a belt-like bias spring 26 is provided between adjacent straight portions 24S of the flow path 24 in the central region of the heat radiating portion 22. Is a point provided.

  A leaf spring is used as the bias spring 26 in the heat pipe 20 of the fourth embodiment. The bias spring 26 is always flat and has a restoring force to return to a flat surface when bent. However, the bias spring 26 is of a nature that is weak against external force so that it can be easily deformed against external force. Therefore, when the temperature deforming member 23 is deformed, the bias spring 26 is deformed following the deformation of the temperature deforming member 23. Further, when the temperature of the heat radiating portion 22 decreases and the temperature deforming member 23 attempts to return to the original state, the bias spring 26 operates so as to speed up its restoration.

  The temperature deformation member 23 provided in the heat radiating portion 22 of the heat pipe 20 of the fourth embodiment is made of the above-described band-shaped shape memory alloy, one using two types of bimetals 23M and 23V alternately, and only the bimetal 23M. Any of those using can be used. That is, in the fourth embodiment of the heat pipe 20, the heat radiating portion 22 may be either wavy at a high temperature or arch-shaped. In the fourth embodiment of the heat pipe 20, no matter what the deformation of the heat radiating part 22 is, when the temperature of the heat radiating part 22 decreases, the restoring force of the bias spring 26 causes no bias spring 26. The heat pipe 20 can return to the flat state in a shorter time than that.

  FIG. 10A shows a state in which the portable terminal 1 showing the state before the heat pipe 20 of the portable terminal 1 to which the fifth embodiment of the disclosed heat pipe 20 is attached is deformed due to high temperature as viewed from the side. Show. FIG. 10 (b) shows a state in which the portable terminal 1 showing a state in which the heat pipe 20 of the portable terminal 1 to which the fifth embodiment of the disclosed heat pipe 20 is attached is heated and deformed is viewed from the side. Show. Furthermore, FIG.10 (c) has shown the state which looked at the portable terminal 1 shown in FIG.10 (b) from diagonally upward.

  The fifth embodiment of the disclosed heat pipe 20 is different from the other embodiments in the deformed shape of the heat radiating portion 22 when the heat radiating portion 22 of the heat pipe 20 becomes high temperature. In the above-described embodiment, the heat radiating portion 22 is deformed into a wave shape or an arch shape. On the other hand, when the heat radiating part 22 becomes high temperature, the heat radiating part 22 of the fifth embodiment is deformed into a cantilever shape with the slit 13 side as a supporting part, and the tip part 25T of the sheet-like member 25 and the housing 11 are deformed. An opening K is formed between the rear surface 11B. For this reason, in the fifth embodiment, the long groove 17 is formed in a portion of the back surface 11B facing the tip portion 25T of the sheet-like member 25, and the bellows member 18 is accommodated in the long groove 17.

  One end of the bellows member 18 is fixed to the bottom surface of the long groove 17, and the other end is fixed to the distal end portion 25 </ b> T of the sheet-like member 25. The bellows member 18 is housed in the long groove 17 when the temperature of the heat dissipating part 22 is low and the heat dissipating part 22 is in close contact with the back surface 11B. On the other hand, when the heat radiating part 22 becomes high temperature, the temperature deformation member 23 is deformed by heat, and the heat radiating part 22 is deformed into a cantilever shape having the slit 13 as a support part. When the heat radiating part 22 is deformed in a cantilevered manner, the leading end 25T of the sheet-like member 25 moves upward from the back surface 11B. The bellows member 18 extends following the front end portion 25T of the sheet-like member 25 moved upward from the back surface 11B, and closes the opening K between the front end portion 25T of the sheet-like member 25 and the back surface 11B.

  As shown in FIG. 10C, a band-shaped temperature deformation member 23 is used for the temperature deformation member 23 used in the heat pipe 20 of the fifth embodiment. As the temperature deformable member 23, a shape memory alloy or bimetal 23M that can be deformed into a cantilever shape as shown in FIG. 10B at a high temperature can be used. The bias spring used in the heat pipe 20 of the fourth embodiment can also be used for the heat pipe 20 of the fifth embodiment.

  As the heat transport device in the embodiment described above, a resin heat pipe can be used, and a resin self-excited vibration heat pipe can be used. The self-excited vibration heat pipe transports heat by the refrigerant flow caused by the phase change of the refrigerant enclosed in the flow path. And by using resin for the sheet-like member of the self-excited vibration heat pipe, the self-excited vibration heat pipe can be provided with flexibility (flexibility). In addition, by using a shape memory alloy for the temperature deformation member and using a bias spring in combination, it is deformed to a shape memorized in the shape memory alloy at a set temperature or higher, and to a bias spring shape at a set temperature or lower. The heat dissipating part can be deformed to follow.

With the configuration of the present application, the following effects can be obtained in a portable terminal including a resin heat pipe or a resin self-excited vibration heat pipe.
(1) The heat of the heating element in the portable terminal can be directly transported and radiated to the outside of the casing by a heat pipe partially exposed to the outside of the casing, and the temperature rise of the casing can be prevented.
(2) By using the heat pipe, the heat radiation surface can be soaked, and the heat radiation efficiency can be improved.
(3) Since the heat dissipation surface is in close contact with the terminal casing when not in use, the casing is thin and portability can be maintained.
(4) Only when the amount of heat generated by the heating element in the housing increases and heat radiation from the outer surface of the housing alone is insufficient, the heat radiation part of the heat pipe is deformed and the heat radiation area is expanded to increase the heat radiation amount. Therefore, the temperature rise of the housing can be prevented.
(5) By using a resin heat pipe or a resin self-excited vibration heat pipe, it is possible to reduce the weight of the heat radiating unit as compared with the case of using a metal plate having the same thickness.

  In the above-described embodiment, the resin heat pipe and the resin self-excited vibration heat pipe are described as the heat transport mechanism, but the heat transport mechanism is not limited to these forms. Other forms of the heat transport mechanism include a resin-made liquid cooling system in which a casing is made of resin and a refrigerant is circulated by a pump. The resin liquid cooling system can be formed of a flow path having a resin casing, a refrigerant, a refrigerant driving pump, and a drive / control circuit thereof.

  The present application has been described in detail with particular reference to preferred embodiments thereof. For easy understanding of the present application, specific forms of the present application are appended below.

(Appendix 1) A portable information terminal,
A slit provided in a casing of the portable information terminal;
A heat receiving portion is provided on one end side, a heat radiating portion is provided on the other end side, and a temperature deforming member disposed on the heat radiating portion is provided, the heat receiving portion is disposed in the vicinity of a heating element inside the housing, Pulled out of the housing through the slit and superimposed on the back surface of the housing, the temperature deforming member is deformed when heat of a predetermined temperature or more is applied, and deforms the heat radiating part away from the back surface. A portable information terminal comprising: a flexible heat transport mechanism.
(Supplementary note 2) The portable information terminal according to supplementary note 1, wherein the heat transport mechanism is a resin heat pipe.
(Supplementary note 3) The portable information terminal according to supplementary note 2, wherein the resin heat pipe is a self-excited vibration heat pipe.
(Additional remark 4) The portable information terminal in any one of Additional remark 1 to 3 in which the said temperature deformation member deforms the said thermal radiation part to a wave shape.
(Supplementary note 5) The portable information terminal according to any one of supplementary notes 1 to 3, wherein the temperature deforming member deforms the heat radiating portion into an arch shape.

(Additional remark 6) The said temperature deformation member is a portable information terminal in any one of additional remark 1 to 3 which deform | transforms the said thermal radiation part into the cantilever which used the said slit side as a support part.
(Additional remark 7) The portable information terminal of Additional remark 6 by which the blindfold member is provided between the front-end | tip part of the said thermal radiation part deform | transformed in the cantilever shape by the said temperature deformation member, and the said back surface.
(Supplementary note 8) The mobile phone according to any one of supplementary notes 1 to 5, wherein the free end portion of the heat radiating portion is formed so as to be movable in the inner direction of the housing on the back surface when the heat radiating portion is deformed. Information terminal.
(Supplementary note 9) The mobile phone according to any one of supplementary notes 1 to 8, wherein a concave portion that is recessed by a thickness of the heat dissipation portion is formed in a portion of the rear surface of the housing where the heat dissipation portion is overlapped. Information terminal.
(Supplementary note 10) The portable information terminal according to any one of supplementary notes 1 to 7, wherein the temperature deformable member is a shape memory alloy.

(Supplementary note 11) The portable information terminal according to any one of supplementary notes 1 to 7, wherein the temperature deformation member is a bimetal.
(Supplementary note 12) The portable information terminal according to any one of supplementary notes 1 to 7, wherein the temperature deformation member is a combination of a shape memory alloy and a bias spring.
(Additional remark 13) The said slit is a portable information terminal in any one of additional remarks 1-12 provided in the back surface of the said housing | casing.

DESCRIPTION OF SYMBOLS 10 Portable information terminal 11 Housing | casing 11B Back surface 13 Slit 16 Recessed part 17 Long groove 18 Bellows member 20 Heat pipe (heat transport mechanism)
21 heat receiving part 22 heat radiating part 23 temperature deformation member (shape memory alloy)
24 flow path 25 sheet-like member 26 bias spring

Claims (5)

A portable information terminal,
A slit provided in a casing of the portable information terminal;
A heat receiving portion is provided on one end side, a heat radiating portion is provided on the other end side, and a temperature deformation member disposed on the heat radiating portion is provided, the heat receiving portion is disposed in the vicinity of a heating element inside the housing, and the heat radiating portion is Pulled out of the housing through the slit and superimposed on the back surface of the housing, the temperature deforming member is deformed when heat of a predetermined temperature or more is applied, and deforms the heat radiating part away from the back surface. A portable information terminal comprising: a flexible heat transport mechanism.   The portable information terminal according to claim 1, wherein the heat transport mechanism is a resin heat pipe.   The portable information terminal according to claim 2, wherein the resin heat pipe is a self-excited vibration heat pipe.   The portable information terminal according to any one of claims 1 to 3, wherein the temperature deforming member deforms the heat radiating portion into a wave shape.   The portable information terminal according to claim 1, wherein the temperature deformation member is a shape memory alloy.

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