JP2006031705A - Electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure for protecting an electric circuit of an electronic device from influence of a leaking liquid medium by holding the leaking liquid medium if a liquid medium leaks from a circulation circuit for a liquid medium in a liquid cooling system of the electronic device. <P>SOLUTION: In the circulation circuit of the liquid medium in the liquid cooling system of the electronic device, a liquid absorbing body is arranged so that it covers a joint and a flexible tube even if the liquid medium leaks from the joint as a component of the circulation circuit or from the flexible tube connected to the joint, and the liquid refrigerant is prevented from being brought into contact with the electronic circuit of the electronic device when the leaking liquid refrigerant is held and hardened by the liquid absorbing body. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electronic device that cools a semiconductor element by circulating a liquid medium.

  Conventional techniques can be found in JP-A-6-266474, JP-A-7-142886, and the like. In an example of Japanese Patent Laid-Open No. 6-266474, an electronic device including a main body housing that houses a wiring board on which a heating element is mounted, and a display device housing that includes a display panel and is rotatably attached to the main body housing. A structure in which a heat receiving jacket attached to a heat generating element, a heat radiating pipe installed in a display device casing, and a liquid driving mechanism are connected by a flexible tube is shown.

  Further, JP-A-7-142886 discloses an example in which the casing is made of metal in the example of JP-A-6-266474.

  In these examples, heat generated by the heat generating element is transmitted to the heat receiving jacket, and the heat is transmitted by transporting the liquid from the heat receiving jacket to the heat radiating pipe by the liquid driving mechanism, and is radiated to the outside air.

JP-A-6-266474 JP-A-7-142886

  In an electronic device typified by a portable personal computer or the like, a high heat generation of an element due to improved performance is remarkable. On the other hand, it is desired to reduce the size and thickness of the housing suitable for carrying.

  In any of the above-described known examples, the heating medium is circulated to cool the heating element in response to an increase in heat generation of the heating element. However, no consideration is given to the case where the liquid medium leaks from the liquid cooling device.

  An object of the present invention is to provide a safe and highly reliable electronic device that can prevent a liquid medium from coming into contact with an electric circuit of the electronic device.

  In the electronic device in which the semiconductor element is mounted inside the housing, the object is to provide a heat receiving member thermally connected to the semiconductor element, a heat radiating member that radiates the received heat, and the heat radiating member and the heat receiving member. The liquid medium leaking from the connecting portion between the joint and the flexible tube, the liquid drive means for working the liquid medium between, and a cooling device in which the heat radiating member and the heat receiving member are connected by a flexible tube through a joint In order to store and process the liquid medium at a predetermined position, a recess is formed in the lower part of the housing where the liquid medium can be retained, and a heat generating electronic component is opposed to the liquid medium retained in the recess. This is achieved by having a leaked liquid medium retention processing means that is disposed in the electronic component heat and can evaporate by heating the station medium in the recess by the electronic component heat.

  ADVANTAGE OF THE INVENTION According to this invention, it can prevent that a liquid medium contacts the electric circuit of an electronic device, and can provide a safe and highly reliable electronic device.

  2. Description of the Related Art Electronic device apparatuses, so-called personal computers (hereinafter referred to as personal computers) include portable laptop computers and desktop computers that are mainly used on desks. Each of these personal computers has a demand for high-speed processing and large capacity year by year, and as a result of satisfying this demand, the heat generation temperature of the CPU, which is a semiconductor element, has increased. This trend is expected to continue in the future.

  On the other hand, these current personal computers are generally air-cooled by a fan or the like. This air-cooled type has a limit in heat dissipation capability, and may not be able to follow the heat dissipation of semiconductor elements that tend to generate heat as described above. However, this can be dealt with by rotating the fan at a high speed or by increasing the size of the fan, but this is not practical because it goes against the reduction in noise and weight of the personal computer.

On the other hand, conventionally, there is an apparatus for cooling a semiconductor element by circulating a liquid medium such as water as heat radiation instead of air cooling.
This cooling device is mainly used for cooling large computers used in companies or banks, and is a large-scale device in which cooling water is forcibly circulated by a pump and cooled by a dedicated refrigerator.

  Therefore, for a notebook computer that is frequently moved and a desktop computer that may be moved due to rearrangement in the office, the above-mentioned water cooling device is not used. Even if it is downsized, it cannot be mounted.

  Thus, various water cooling devices that can be mounted on a small personal computer have been studied as in the above-mentioned conventional technology. At the time of filing of this conventional technology, the heat generation temperature of the semiconductor element was not as high as in recent years. Even so, personal computers equipped with water cooling devices have not been commercialized.

  On the other hand, the present invention makes it possible to greatly reduce the size of the water-cooling device by using an aluminum alloy, a magnesium alloy, or the like that has a good heat dissipation for the casing that forms the outline of the computer main body. It has become possible.

  However, even though the liquid medium is in a sealed space, it is the most important issue to prevent leakage of the liquid medium, particularly in a notebook personal computer that moves frequently.

  Although there is a problem of liquid permeation from the flexible tube, it is clear that the portion where there is a possibility of liquid leakage is a pipe connection portion.

  Therefore, the present invention has been variously studied in order to prevent liquid leakage from the connecting portion of the pipe.

Hereinafter, the examination result of this invention is demonstrated using drawing.
FIG. 1 is a perspective view of an electronic device provided with the present invention.
In FIG. 1, the electronic device includes a main body case 1 and a display case 2 provided with a display (not shown). The main body case 1 is provided with a keyboard 3, a wiring board 4 on which a plurality of elements 7 are mounted, a hard disk drive 5, an auxiliary storage device (for example, a floppy disk drive, a CD drive, etc.) 6, a battery 13, and the like. For the sake of explanation, the keyboard 3 is shown in a removed state.

  On the wiring board 4, an element (hereinafter referred to as “CPU”) having a particularly large calorific value such as a CPU (Central Processing Unit consisting of semiconductor elements) 7 is mounted. A water cooling jacket 8 is attached to the CPU 7, and both are connected via a flexible heat conductive member (for example, a silicon rubber mixed with a heat conductive filler such as aluminum oxide). A metal heat radiating plate 10 to which a heat radiating pipe 9 is connected is installed on the back surface (inner case) of the display case 2. Note that the metal heat dissipation plate 10 may be omitted and the heat dissipation pipe 9 may be directly connected to the display case 2 by making the display case 2 itself made of metal (for example, aluminum alloy or magnesium alloy). A pump 11 that is a liquid transporting means is installed in the main body case 1.

  The water cooling jacket 8, the heat radiating pipe 9, and the pump 11 are connected by a flexible tube 12, and a liquid medium 15 (for example, water, antifreeze liquid, etc.) enclosed inside by the pump 11 circulates. The heat generated by the CPU 7 is transmitted to the liquid medium 15 that circulates in the water-cooling jacket 8, and passes through the surface of the display case 2 from the metal heat radiating plate 10 installed on the back surface of the display while passing through the heat radiating pipe 9. Heat is dissipated.

  As a result, the liquid medium 15 whose temperature has been lowered is sent again to the water cooling jacket 8 via the pump 11. In addition, a tank 14 connected to the heat radiating pipe 9 is installed at the upper back of the display case 2, and a liquid medium 15 is contained in the tank 14. The tank 14, the heat radiating pipe 9, the flexible tube 12, the pump 11, and the water cooling jacket 8 are closed circulation circuits for the liquid medium 15, and the liquid medium 15 is circulated by operating the pump 11.

  As shown in FIG. 1, the internal liquid medium 15 is normally circulated in a closed state during operation, but the tank 14, the heat radiating pipe 9, the flexible tube 12, the pump 11 and the like constituting the circulation circuit In the unlikely event that the internal liquid medium 15 leaks from the water cooling jacket 8 or the like, or from the joint between the flexible tube 12 and each component, the following measures are taken.

The measure will be described with reference to FIG.
FIG. 2 is a cross-sectional view of a connection portion between the pump 11, the water cooling jacket 8, and the flexible tube 12 according to the embodiment.
In FIG. 2, suitable joints 11a and 8a and a tightening band (plate shape, coil spring shape) for preventing disconnection are used for the connecting portion, although not shown. In addition, the material of the flexible tube 12 is butyl rubber or the like with little moisture permeation.

  Furthermore, in the present embodiment, the joints 11a, 8a and the flexible tube 12 are covered by assuming that the internal liquid medium 15 leaks from the joints 11a, 8a and the flexible tube 12 during long-term use. In addition, a liquid absorber 16 is disposed. The liquid absorber 16 may be one that absorbs and holds a liquid medium, or a water-absorbing polymer that reacts with the liquid medium 15 to solidify the liquid medium.

  As a result, even if the liquid medium 15 leaks, it can be held and solidified by the liquid absorber 16 so that the CPU 7a and the like mounted on the wiring board 4 are not affected. Note that a heat shrinkable tube may be used instead of the liquid absorber 16, and the heat shrinkable tube may be shrunk using the heat of the circuit in which the liquid medium circulates to be in close contact with the flexible tube 12 and the joints 11a and 8a. Similarly, an effect of preventing the liquid medium from leaking outside the circulation circuit can be obtained.

FIG. 3 is a cross-sectional view of a connecting portion of the pump 11, the water cooling jacket 8, and the flexible tube 12 according to another embodiment of the present invention.
In FIG. 3, assuming that the liquid medium 15 leaks from the joints 11 a, 8 a and the flexible tube 12 during long-term use, the sleeve is formed so as to cover the joints 11 a, 8 a and the flexible tube 12. 17 is arranged. The sleeve 17 is provided with a minute gap with the flexible tube 12 and the joints 11a and 8a, and holds the liquid medium 15 leaked by the surface tension of the gap. Furthermore, the water-repellent treatment is performed on the inner surface of the sleeve 17 to improve the retention of the liquid medium 15.

  As a result, even if the liquid medium leaks, the liquid medium is held in the gap between the sleeve 17 and the flexible tube 12 and the joints 11a and 8a. 4 does not reach the CPU 7a or the like mounted on the CPU 4.

  In the embodiment shown in FIGS. 2 and 3, the connection portion between the pump 11, the water cooling jacket 8 and the flexible tube 12 has been described as an example, but the connection between the tank 14, the heat radiating pipe 9 and the flexible tube 12 is described. The same effect can be obtained by applying the present invention to other connection parts such as the parts.

FIG. 4 is a partially enlarged sectional view of a main body case 1 which is another embodiment of the present invention.
In FIG. 4, assuming that the liquid medium 15 inside the liquid medium 15 circulating circuit of the liquid medium 15 shown in FIG. A medium holding plate 18 is disposed. The liquid medium holding plate 18 is installed with a small gap from the main body lower case 1b, and holds the liquid medium leaked by the surface tension of the liquid medium 15 in the gap.

  As a result, even if the liquid medium 15 leaks, the liquid medium is held in the gap between the main body lower case 1b and the liquid medium holding plate 18, and the liquid medium 15 does not change even if the electronic device is carried and the posture changes. The CPU 7a or the like mounted on the wiring board 4 is not reached.

FIG. 5 is a partially enlarged sectional view of a main body case 1 which is another embodiment of the present invention.
In FIG. 5, assuming that the liquid medium 15 inside leaks from each component of the circulation circuit of the liquid medium 15 shown in FIG. 1 and its joints, a recess is formed in the bottom of the lower case 1b. 1C is provided.

  The lower case recess 1C stores the leaked liquid medium 15, and is lower than other portions of the main body lower case 1b so that the leaked liquid medium is always stored in the recess 1C. Moreover, the leaked liquid medium 15 can be evaporated by installing a heating element in the recess 1C. Note that the heat generated by the CPU 7a may be used instead of separately installing a heating element to evaporate the liquid medium.

  Furthermore, an electronic device can be stopped by installing a leakage sensor in the recess 1C and detecting leakage of the liquid medium 15.

FIG. 6 is a partially enlarged cross-sectional view of a main body case 1 which is another embodiment of the present invention.
In FIG. 6, assuming that the liquid medium 15 inside leaks from the components of the circulation circuit of the liquid medium 15 shown in FIG. A recess 1C and a liquid absorber 16 are provided. The leaked liquid refrigerant 15 always gathers in the recess 1C, and is held and solidified by the liquid absorber 16 through the hole 1e of the main body lower case 1b. The main body upper case 1 a is provided with a recess 1 f, and the small-diameter pipe 19 is installed in the recess so as to penetrate the main body upper case 1 a and close to the wiring board 4.

  This is because even if the leaked liquid medium 15 reaches the wiring board 4, it is sucked up by the capillary phenomenon of the small diameter pipe 19 and held and solidified by the liquid absorber 16 installed in the recess 1f of the main body upper case 1a. It is something to be made. The wiring board 4 is provided with holes 4a so that the liquid medium does not stay on the wiring board.

  As a result, even if the liquid medium 15 leaks, the liquid medium is held or solidified by the liquid absorber 16 installed in the main body case 1, and the liquid medium remains in the electronic apparatus even if the electronic apparatus is carried and the posture is changed. It is possible to avoid contact with electrical components.

FIG. 7 is a partially enlarged sectional view of a main body case 1 which is another embodiment of the present invention.
In FIG. 7, the main body upper case 1a and the lower case are assumed to be leaked from each component of the circulation circuit of the liquid medium 15 shown in FIG. The liquid absorber 16 is provided in the part of the connector 20 taken out from the main body case 1 and the contact surface part 1g with 1b. The leaked liquid refrigerant 15 is held and solidified by the liquid absorber 16. Accordingly, even if the liquid medium leaks, the liquid medium is held or solidified by the liquid absorber installed in the main body case, and the liquid medium 15 does not leak outside the main body case 1.

FIG. 1 is a perspective view of an electronic apparatus according to the present invention. FIG. 2 is a cross-sectional view of the flexible tube connecting portion of the first embodiment. FIG. 3 is a cross-sectional view of the flexible tube connecting portion of the second embodiment. FIG. 4 is a partially enlarged cross-sectional view of the main body case of the third embodiment. FIG. 5 is a partially enlarged cross-sectional view of the main body case of the fourth embodiment. FIG. 6 is a partially enlarged cross-sectional view of the main body case of the fifth embodiment. FIG. 7 is a partially enlarged cross-sectional view of the main body case of the sixth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Main body case, 2 ... Display case, 3 ... Keyboard, 4 ... Wiring board 7 ... CPU, 8 ... Water cooling jacket, 9 ... Radiation pipe, 10 ... Radiation metal plate, 11 ... Pump, 12 ... Flexible tube, 14 ... Tank 15 ... Liquid medium, 16 ... Liquid absorber, 17 ... Sleeve, 18 ... Liquid medium holding plate, 19 ... Small diameter pipe.

Claims (1)

In an electronic device with a semiconductor element mounted inside the housing,
A heat-receiving member thermally connected to the semiconductor element; a heat-dissipating member that dissipates the received heat; a liquid driving means that works a liquid medium between the heat-dissipating member and the heat-receiving member; and the heat-dissipating member and the heat-receiving member. It has a cooling device in which the members are connected by a flexible tube via a joint,
An electronic component that generates heat by forming a recess capable of retaining the liquid medium in the lower portion of the housing in order to store and process the liquid medium leaked from the joint between the joint and the flexible tube at a predetermined position. Is disposed so as to be opposed to the liquid medium retained in the recess, and has a leaked liquid medium retention processing means that allows the station medium in the recess to be heated by the electronic component heat to be evaporated. Electronic device characterized.

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