JPS6150235B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a boiling cooling device, and particularly to a boiling cooling device suitable for cooling a heating element by the boiling and condensing action of a refrigerant liquid.

[Conventional technology]

FIG. 1 is an explanatory diagram showing a conventional boiling cooling device, in which a heating element 1 to be cooled is housed in a container 3 together with a liquid refrigerant 2 that can boil. A condenser 4 is arranged above the container 3, and the lower end of the condenser 4 is communicated with the upper end of the container 3.

In such a boiling cooling device, when the heating element 1 generates heat due to electricity, etc., and its temperature rises above the boiling point of the refrigerant 2, the refrigerant 2 absorbs the latent heat of vaporization from the heating element 1 and evaporates. Steam is sent to condenser 4. Since the outside of the condenser 4 is cooled by air or the like, the refrigerant vapor sent inside releases its latent heat, condenses and liquefies, descends by gravity, and returns to the inside of the container 3. do. That is, according to such a boiling cooling device, since the heating element 1 is cooled using the boiling and condensing action of the refrigerant 2, a high cooling effect can be obtained.

However, in such a boiling cooling device, when non-condensable gas such as air mixes inside the condenser 4, the non-condensable gas remaining without condensing inside the condenser 4 forms a thermal insulation layer. This prevents the refrigerant vapor from touching the pipe wall of the condenser 4, significantly deteriorating the cooling characteristics.

Conventionally, such boiling cooling equipment has an airtight structure such as welding to prevent non-condensable gases such as air from entering the cooling equipment, and after the inside is evacuated and completely degassed. , degassed refrigerant, such as degassed chlorofluorocarbon, is injected.

However, even in such an airtight boiling cooling device, after long-term use, air enters through minute pinholes and the like, degrading its cooling characteristics. In addition, in such a boiling cooling device, in order to obtain an airtight structure, all joints are made of metal such as welding, so if the heating element 1 housed inside breaks down, part of the device will be damaged. There is a problem in that the heating element 1 must be taken out by cutting it.

On the other hand, Japanese Patent Application Laid-Open No. 53-95352 discloses that a conduit is provided between the top of the condenser and the bottom of the container, and a check valve and a tank for separating non-condensable gas and refrigerant vapor are installed in this conduit. An evaporative cooling device is disclosed in which the non-condensable gas is removed from the condenser.

[Problem that the invention seeks to solve]

However, the boiling cooling device described in the above publication,
Since the non-condensable gas in the condenser is removed via the check valve, there is a risk that the non-condensable gas may not be removed smoothly.

In other words, in the known device, when the refrigerant in the container evaporates and the pressure in the condenser increases, this pressure acts on the liquid level of the refrigerant in the container, causing the refrigerant in the container to flow through the tank and the check valve. Push it into the pipe line. Therefore, the pressure in the pipeline downstream of the check valve increases in accordance with the increase in pressure in the condenser. Therefore, the pressure difference between the top of the condenser, which is upstream of the check valve, and the inside of the pipeline, which is downstream of the check valve, is extremely small, and it is difficult to operate the check valve with such a small pressure difference. That's not realistic. As a result, the non-condensable gas that has entered the condenser remains in the condenser without being removed from the condenser, reducing cooling efficiency.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a boiling cooling device that can improve cooling characteristics without having an airtight structure.

[Means for Solving the Problems] The present invention provides a first container in which a heating element is immersed and stored in a boilable refrigerant liquid, and a lower end portion is arranged in communication with the upper part of the first container. a second container whose lower part where the refrigerant liquid accumulates is connected to the lower part of the first container, and the lower part of the second container is connected to the top of the condenser, A communication pipe that guides the gas in the condenser into the refrigerant liquid in the second container, and a flow restriction provided in a communication section between the first container and the second container to restrict the flow of the refrigerant liquid. A boiling cooling device characterized by having a means.

[Effect]

In the present invention configured as described above, when the refrigerant in the first container evaporates due to the heat generated by the heating element and flows into the condenser, and the pressure in the condenser increases, the refrigerant in the first container evaporates and flows into the condenser. Although the refrigerant tends to move toward the second container due to the pressure, the movement of the refrigerant is regulated by the flow restriction means provided in the communication section between the first container and the second container. On the other hand, since the top of the condenser is connected to the bottom of the second container, as the pressure inside the condenser increases, the gas consisting of refrigerant vapor and non-condensable gas inside the condenser increases in pressure. The non-condensable gases in the condenser can be expelled into the lower second vessel. As a result, the boiling cooling device does not need to have an airtight structure, and cooling efficiency can be improved.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 2A to 2F are explanatory diagrams showing one embodiment of the evaporative cooling device according to the present invention. first container 1
1 houses a heating element 12 and a refrigerant 13,
A lower end portion of the condenser 14 is disposed in communication with the upper portion thereof. Further, the lower end of the first container 11 is communicated with the lower end of the second container via a throttle 15 serving as a flow regulating means. The cross-sectional area of the lower part of the second container 16 is set smaller than the side cross-sectional area of the upper part. Further, the top of the condenser 14 and the lower end of the second container 16 are communicated via a communication pipe 17.

Next, the operation of the above embodiment will be explained. Second
Figure A shows a state in which the heating element 12 is not generating heat, the refrigerant 13 in the first container 11 is not boiling, and the condenser 14 and the second container 16 are not boiling.
In the upper part of the refrigerant vapor and air as a non-condensable gas are mixed, and in the lower part of the second container 16 and the lower part of the communication pipe 17, the liquefied refrigerant 13 is accumulated.

When the heating element 12 generates heat from this state by being energized or the like, the refrigerant 13 in the first container 11 boils and evaporates, and refrigerant vapor flows into the condenser 14, as shown in FIG. 2B. and increases the pressure inside the condenser 14. In the condenser 14, before the heating element 12 generates heat, there is a nearly uniform mixed gas (gas) of non-condensable gas air and refrigerant vapor. A large amount of refrigerant vapor flows from below, and the upper part of the condenser 14 becomes a mixed gas containing a large proportion of air with a low specific gravity, and the lower part becomes a mixed gas containing a large proportion of refrigerant vapor with a large specific gravity.

The pressure in the condenser 14 acts to push down the refrigerant liquid level in the first container 11 via the lower communication part of the condenser 14, and the pressure in the condenser 14 and the second
This acts to push down the refrigerant liquid level in the communication pipe 17 that communicates with the container. However, the communication portion between the first container 11 and the second container 16 is provided with a restriction 15 as a flow restriction means, and the refrigerant 13 in the first container 11 is allowed to flow through the flow resistance based on the restriction 15. Therefore, it cannot be easily transferred to the second container 16 side. Therefore, the high pressure mixed gas in the upper part of the condenser 14, as shown in FIG. 2B,
Pushing down the refrigerant liquid level of the communication pipe 17, the second container 1
6 into the second container 16.
The mixed gas that has flowed into the second container 16 rises through the refrigerant accumulated in the second container, and then flows into the second container 16.
reaches the top of the container 16. The pressure inside the second container 16 gradually increases due to the inflow of the mixed gas from the condenser 14, and the refrigerant vapor in the mixed gas is condensed and liquefied in the second container 16, resulting in the second
into the lower end of the container 16.

After passing through a transient state due to the start of heat generation of the heat generating element 12, in the steady state shown in FIG. The diffusion gas gradually decreases and is eventually filled with high density refrigerant vapor, so that the interior of the second container 16 accommodates high density air and low density refrigerant vapor. That is, even if air is mixed inside the condenser 14 before the heating element 12 generates heat, the air is gradually sent into the second container 16 side by the heat generation of the heating element 12. Note that in a steady state, the refrigerant 13 condensed in the second container 16 drips onto the lower end of the second container 16, making the liquid level in the second container 16 higher than the liquid level in the first container 11. raise. However, the first container 11 and the second container 12 are in communication with each other through the throttle 15, and the refrigerant 13 forming a high liquid level in the second container 16 is transferred to the first container over time. The liquid flows back into the container 11. Therefore, the liquid levels in the first container 11 and the second container 16 in the steady state are approximately the same, and the pressure of the refrigerant vapor in the condenser 14 and the air and The pressure is the same as the pressure of the mixed gas consisting of refrigerant vapor.

When the heating state of the heating element 12 is stopped from such a state, the refrigerant vapor in the condenser 14 is liquefied by cooling, and the pressure in the condenser 14 is reduced. Therefore, the inside of the second container 16 is
The pressure in the second container 16 is relatively higher than that in the container 11 and the condenser 14, and due to the influence of the relatively higher pressure in the second container 16, the refrigerant 13 stored in the lower part of the second container 16 is As shown in FIG. 2D, the condenser 14 and the first
The water is refluxed into the container 11. In addition, at this time, the second
The refrigerant 13 on the container 16 side also flows back to the first container 11 side through the throttle 15, albeit in a small amount.

In this way, the refrigerant 13 in the communication pipe 17 is
When the refrigerant vapor with a high specific gravity stored in the second container 16 is completely recirculated to the side of the container 11, as shown in FIG. Therefore, air with low specific gravity remains in the second container 16.

After a long period of time in this state,
The refrigerant 13 in the first container 11 flows through the throttle 15 into the second container 16 until the pressure balance between the first container 11 and condenser 14 and the second container 16 is balanced. Flows into the lower part and connects to the communication pipe 17.
A refrigerant 13 is accommodated at the lower end side at the same liquid level as the first container 11, and as shown in FIG. 2F,
The similar heating element 12 in FIG. 2A returns to its state before heating.

According to the boiling cooling device according to the above embodiment, even if air is mixed in the condenser 14 before the heating element 12 generates heat, the air inside the heating element 14 is gradually removed as the heating element 12 generates heat. The refrigerant vapor can be sent to the second container 16 side and come into direct contact with the pipe wall of the condenser 14, and cooling performance can be improved without requiring a strict airtight structure. Therefore, in this embodiment, there is no need for a completely welded structure, and a connection structure consisting of an O-ring, a gasket, etc. can be adopted, and the heating element 12
Even if the heating element 12 breaks down, the heating element 12 can be easily taken out by opening and closing the apparatus without disconnecting it. Furthermore, when injecting the refrigerant 13, there is no need to deaerate the device, and the refrigerant 13 can also be a general refrigerant that has not been deaerated.
It is easy to manufacture and its handling is simplified. Furthermore, since the cross-sectional area of the lower part of the second container 16 is set smaller than the cross-sectional area of the upper part, the second container 16 and the communication pipe 1 are
It becomes possible to set a liquid seal section at the bottom of 7.

Furthermore, in this embodiment, the refrigerant does not easily transfer between the containers because the aperture 15, which is a flow regulating means, is provided between the first container 11 and the second container 16. Therefore, unlike the piping described in JP-A-53-95352, in which a check valve is interposed,
When the heating element 12 starts generating heat, the pressure difference becomes large between the first container 11 side and the second container 16 side, and the mixed gas in the condenser 14 easily flows into the second container 16. , the non-condensable gas in the condenser 14 can be efficiently discharged.

FIG. 3 is an explanatory diagram showing another embodiment of the evaporative cooling device according to the present invention. This embodiment differs from the previous embodiment in that a pressure relief valve 18 that can be opened at a predetermined pressure or higher is provided at the upper part of the second container 16 in which the mixed gas with high air concentration accumulates.
By disposing such a pressure relief valve 18, when the air pressure within the second container 16 reaches a predetermined value or more,
Air can be discharged to the outside, the pressure inside the device can be lowered, and the refrigerant concentration inside the condenser 14 can be increased, thus making it possible to further improve the cooling characteristics of the device.

In addition, in each of the above embodiments, the first container 1
Although the case has been described in which the aperture 15 is interposed between the first container 16 and the second container 16 as a flow restricting means, a check valve may be used instead of the flow restricting means.

〔Effect of the invention〕

As described above, the boiling cooling device according to the present invention has the effect that cooling performance can be improved with a simple structure without requiring an airtight structure.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing a conventional boiling cooling device, FIGS. 2A to 2F are explanatory diagrams showing different operating states in an embodiment of the present invention, and FIG. 3 is a system diagram showing a boiling cooling device according to the present invention. It is an explanatory view showing other examples of such a boiling cooling device. DESCRIPTION OF SYMBOLS 11... First container, 12... Heating element, 13... Refrigerant, 14... Condenser, 15... Throttle (flow regulating means), 16... Second container, 17... Communication pipe, 18...
Pressure relief valve.

Claims (1)

[Scope of Claims] 1. A first container in which a heating element is immersed and stored in a boilable refrigerant liquid, a condenser whose lower end is arranged in communication with the upper part of the first container, and the refrigerant. A second container whose lower part where liquid accumulates is communicated with the lower part of the first container, and the lower part of the second container is communicated with the top of the condenser, and the gas in the condenser is connected to the lower part of the first container. It is characterized in that it has a communication pipe that leads into the refrigerant liquid in the second container, and a flow regulating means that is provided in a communication section between the first container and the second container and regulates the flow of the refrigerant liquid. Micro-boiling cooling device. 2. The boiling cooling device according to claim 1, characterized in that a pressure relief valve is disposed in the upper part of the second container. 3. The boiling cooling device according to claim 1, wherein the second container has a lower cross-sectional area smaller than an upper cross-sectional area. 4. The boiling cooling device according to claim 1, wherein the flow regulating means is a throttle. 5. The boiling cooling device according to claim 1, wherein the flow regulating means is a check valve.