JPS5854356B2 - heat transfer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a safety device for preventing explosions, etc. for a heat transfer device that transfers latent heat through the evaporation and condensation of an evaporative heat medium and the circulation action of capillary force or gravity. The present invention relates to a heat transfer device provided with a heat transfer device.

Conventionally, the above-mentioned heat propagation device does not have a safety device to control the heat source, etc., so if the heating input from the heat source to the heating section is large and the heat dissipation output of the heat dissipation section is small, the heat propagation will increase accordingly. The temperature and pressure inside the device's closed container rose rapidly, making it extremely dangerous.

Also, for this purpose, the strength of the sealed container may be made stronger than necessary, or
The welded portion of the sealed container had to be made stronger than necessary, making it difficult to manufacture.

In order to eliminate the above-mentioned drawbacks, the present invention provides a thin film part in a part of the airtight container of the heat transfer device, and when the temperature of the heat transfer device becomes abnormally higher than the set temperature, the thin film part The present invention provides a safety device that prevents an explosion by being broken by a needle or the like provided on a thermally responsive body.

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

Figure 1 is a cross-sectional view of a heat transfer device showing a conventional embodiment;
The figure is a sectional view of a heat transfer device showing an embodiment of the present invention.

Reference numeral 1 denotes a heat propagation device in which a wick 3 having a capillary force such as a wire mesh, metal fiber, sintered alloy, groove, etc. is installed on the inner wall of a closed container 2 made of steel, stainless steel, aluminum, etc.

4 is an evaporative heat medium (working fluid) such as acetone, water, mercury, etc.
The wick 3 is sealed so as to leak sufficiently.

5 is a deaerated cavity, 6 is a heating section, and 7 is a heat dissipation section.

8 is a stepped portion provided on the side of the heat dissipating portion 7, and 8' is a hole thereof.

A thin film part 9 made of metal foil or the like is fixed to the step part 8 with a backing 10 sandwiched therebetween, and the cavity 5 on the side of the closed container 2 is sealed by the thin film part 9.

The thin film part 9 is inserted into the stepped part 8 and is screwed and held down by the holding ring 11, so that installation is easy.

12 is a thermally responsive body such as a bimetal that senses heat and is displaced.

The heat-responsive body 12 is disposed in a heat-immersed manner on the side of the heat dissipation section 7, which is the condensation side of the working fluid, in a container near the thin-film section 8 so that a part thereof faces the thin-film section 8 at a certain distance. In response to the temperature of the container 2, the portion facing the thin film portion 8 gradually displaces in a direction approaching the thin film portion 8 (in the direction of the arrow in the figure).

Reference numeral 13 denotes a needle portion protruding from the surface of the thermally responsive body 12 facing the thin film portion 8, and the needle portion 13 moves toward the thin film portion 8 as the thermally responsive body 12 is displaced.

Next, the operation in the above embodiment will be explained.

In the conventional heat transfer device 1 shown in FIG.
When the heating part 6 is heated, the heat medium (working fluid) 4 in this part evaporates, the vapor pressure increases, and the vapor pressure gradient flows toward the heat radiation part 7 of the closed container 2 where the vapor pressure is low.

That is, the vapor of the heat medium 4 flows from the heating section 6 of the closed container 2 toward the heat radiation section 7 .

The steam is then cooled and condensed in the heat radiating section 7, and the heat medium 4 is subjected to capillary action (or gravity) inside the wick 3 and returns from the heat radiating section 7 to the heating section 6.

This heat medium 4 forms the above-mentioned two-phase flow and radiates the latent heat of phase change obtained in the heating part 6 in the heat radiating part 7.
A large amount of heat is transmitted from the radiator to the heat radiator 7.

At this time, the closed container 2 is almost at the same temperature, and there is almost no temperature difference between the heating section 6 and the heat radiation section 7.

In this case, the thermally responsive body 12 is displaced in a direction approaching the thin film part 9 in response to the input from the heating part 6, but in a steady state, the needle part 13 does not reach the thin film part 9 and is held at a certain distance. That will happen.

However, if the heating input to the heating part 6 is greater than the heat source and the heat radiation output from the heat radiation part is small, the heat medium 4 in the closed container 2
evaporates rapidly and the temperature and pressure rise rapidly, which is dangerous.

In this case, when the temperature rises abnormally, the thermally responsive body 12 also reacts to the abnormally high temperature and is displaced in a direction closer to the thin film portion 8 to a greater degree than in a steady state.

When this displacement exceeds a certain amount, that is, when the temperature of the heat dissipation part exceeds a certain temperature, the tip 13 of the needle part 13 finally pierces the thin film part 9 and breaks the thin film.

As a result, the high pressure gas inside the container 2 is released to the outside, lowering the pressure inside the container 2.

Therefore, it is very safe because the high-pressure gas inside the container 2 flows out before it explodes, and the heat-responsive body 12 senses the temperature of the heat radiation part 7 and gradually approaches the thin film part 8. The heating state of the heat radiating section 7 can be known from the operation of the thermally responsive body 12 without the need for a thermometer.

That is, it is possible to know whether steady heating or abnormal heating is occurring based on the amount of displacement of the thermally responsive body 12.

Therefore, it is also possible to detect abnormal heating and weaken or stop the heating input before the thin film part 8 is torn by the needle part 13 of the thermally responsive body 12.

As is clear from the above description, the present invention provides a stepped portion 8 and a hole 8' in a part of the airtight container 2, and a thin film portion 9 in the hole 8'.
is tightened with a retaining ring 11, a bimetallic needle part 13 is provided in the vicinity of the thin film part '9, and the other end of the bimetallic part 12' is brought into contact with the closed container 2. If the temperature of the closed container 2 of the propagation device 1 rises too high, the thin film portion 9 will be ruptured and a safety device can be provided to prevent an explosion.

Note that the location where the thin film part thermally responsive body is provided is not limited to the heat radiation part, and the thing that breaks the thin film part is not limited to the needle.

Additionally, the thermally responsive body is not limited to bimetals.

Heat propagation devices are not limited to those with wicks, and the shape of heat propagation devices is not limited to pipe-shaped, square-shaped closed containers, but can be applied to all types, such as double-walled heating containers. It is not a moat that can be installed and applied.

Further, according to the present invention, (1) The structure is simple, so manufacturing is easy and there is no failure.

(2) Can be provided at low cost.

(3) It has good sensitivity, and the breakdown temperature and pressure can be set arbitrarily by selecting the material and thickness of the thin film part, the characteristics of the bimetal, and the distance between the thin film part and the needle part.

(4) The thin film part can be easily attached and replaced.

It has many benefits such as:

As described above, the present invention encloses an evaporative heat medium in a closed container,
In contrast to those in which heat propagates through the evaporation and condensation action of the heating medium, a thin film section is provided on the condensation side of the closed container, which is the high temperature side, and at least a part of the thin film is disposed in the vicinity of the thin film section, facing the thin film section. A heat-responsive body that gradually displaces toward the thin film portion in response to a rise in the temperature of the sealed container is provided in a heat-immersed manner, and a needle portion is provided on the surface of the heat-responsive body facing the thin film portion. This is a heat transfer device.

Therefore, when the closed container is abnormally heated to a temperature higher than the set temperature, the thermally responsive body gradually displaces in response to this abnormal heating.
This displacement allows the needle to break through the thin film part and release the high-temperature gaseous heat medium to the outside, thereby preventing the sealed container from being destroyed by explosion or the like.

In this case, since the thermally responsive body gradually displaces in response to temperature, if the displacement of the thermally responsive body is made visible, the state of heating on the heat radiating portion side can be determined from the state of this displacement.

In other words, this thermally responsive body can serve as a thermometer.

Therefore, by detecting abnormal heating from this state of displacement and weakening or stopping the heating input, it is possible to deal with abnormal heating before the thin film part is torn by the needle part.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a heat transfer device showing a conventional embodiment;
The figure is a sectional view of a heat transfer device showing an embodiment of the present invention. 1: Heat propagation device, 2: Sealed container, 4: Heat medium, 5: Cavity, 8: Step part, 8': Hole part, 7: Thin film part, 12: Bimetal, 13: Needle part.

Claims (1)

[Claims] 1. In a device in which an evaporative heat medium is sealed in a closed container and heat is transferred by the evaporation and condensation action of the heat medium, a thin film portion is provided in the heat dissipation part of the closed container on the condensation side. , a thermally responsive body is provided in the vicinity of the thin film part, at least a part of which faces the thin film part, and is displaced in a direction approaching the thin film part in response to a rise in the temperature of the closed container, and this thermally responsive body A heat propagation device characterized in that a needle portion is provided on a surface facing a thin film portion of the body.