JPH0510583B2 - - Google Patents

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to an expansion tank for a cooling water supply device that cools semiconductor elements, electronic devices, etc. using pure water, and particularly relates to an expansion tank for a cooling water supply device that uses pure water to cool semiconductor devices, electronic devices, etc. This invention relates to an expansion tank for a cooling water supply device that maintains the quality of the cooling water by injecting an inert gas into the cooling water to prevent direct contact between the cooling water and the atmosphere.

[Prior art and its problems]

2. Description of the Related Art A cooling water circulation device as shown in FIG. 3 is known as a cooling water supply device for cooling and keeping cool objects such as semiconductor elements and electronic devices. In the figure, a cooling water circulation system 1 has a circuit 2 that circulates cooling water as a refrigerant, and this circuit 2 includes a pump 3 that circulates the cooling water in the direction of the arrow, and cools the cooling water by dissipating the heat of the cooling water. a radiator 4 that gives the water heat absorption capacity again;
A cooler 6, which is heat-transferably incorporated into the object to be cooled 5, through which cooling water flows, and an expansion tank 7, which absorbs expansion and contraction of the cooling water, are successively installed. According to the cooling water circulation circuit described above, the radiator 4
The cooling water cooled by the cooling water is circulated and supplied to the cooler 6, and the cooling water cools the object 5 to be cooled. However, in this cooling system, when tap water is used as a cooling medium, various troubles occur.
In other words, the conductivity of normal tap water is 150 to 300 μs/cm.
It dissolves many corrosive factors such as chlorine ions. Therefore, when tap water is used as cooling water, metal corrosion tends to progress rapidly and it is not possible to ensure the high reliability and long life required for electronic devices and the like. Under these circumstances, pure water is used as a cooling medium. However, on the other hand, these pure waters have the property of easily dissolving O ₂ and CO ₂ in the air from the surface of the pure water when they come into contact with the atmosphere, and this dissolved O ₂ and CO ₂ is extremely corrosive to metals. It is known to be highly sensitive. In order to solve these problems, it may be possible to make the expansion tank a closed type and cut it off from the atmosphere, but the cooling water in the cooling water circulation circuit expands and contracts due to temperature changes within the system. The cooling water in the expansion tank 7 also decreases due to changes in water temperature and natural evaporation.
It is disadvantageous for the expansion tank to be of closed construction since the water level within the expansion tank 7 fluctuates and thereby the pressure in the space above the free surface within the expansion tank 7 changes.
Furthermore, as shown in FIG. 4, an anaerobic plate 8 is placed on the free surface of the cooling water in the expansion tank 7 to prevent the cooling water from coming into direct contact with the atmosphere. However, in this case as well, since it is impossible to completely separate the cooling water from the atmosphere, O ₂ and CO ₂ gases and microparticles can dissolve in the cooling water, causing corrosion of the metal parts of the cooling water circulation circuit, and causing scaling. It is unavoidable that this phenomenon occurs.

[Purpose of the invention]

In view of the above points, the purpose of this invention is to avoid direct contact between the cooling water stored in the expansion tank and the atmosphere, and to automatically supply pure water when the liquid level in the expansion tank drops below the standard water level. It is an object of the present invention to provide an expansion tank for a cooling water supply device that can be replenished and maintain the pressure on the liquid surface at approximately atmospheric pressure.

[Key points of the invention]

This invention has achieved the above object by sequentially incorporating a pump, a radiator, and a cooler into a cooling water circulation circuit, and further incorporating an expansion tank on the suction side of the pump that stores cooling water inside and leaves an upper space. In the water supply device, an auxiliary tank that fills the space above the free surface of the cooling water stored in the expansion tank with an inert gas so as to be constantly supplied, and that supplies pure water when the free surface falls below a reference water level. and a check valve capable of discharging the inert gas to the outside of the expansion tank. The auxiliary tank is preferably provided integrally at the top of the expansion tank so that pure water can be replenished by gravity, and nitrogen gas is preferably used as the inert gas.

[Embodiments of the invention]

Hereinafter, the first embodiment of the present invention will be described.
This will be explained with reference to the figures and FIG. In the figure, nitrogen gas 12 is supplied from a gas cylinder 18 and a regulator 19.
The microscopic foreign matter is removed by the filter 20 and sent to the flow controller 17. The pure water 11 in the expansion tank 10 is controlled by the float controller 17.
A constant amount of nitrogen gas 12 is always supplied inside the expansion tank 10, and the free surface of pure water inside the expansion tank 10 is filled with nitrogen gas 12. This prevents the pure water 11 in the expansion tank 10 from coming into direct contact with the atmosphere, and maintains the quality of the pure water. Note that the nitrogen gas supplied into the expansion tank 10 at a constant pressure is discharged to the atmosphere via the check valve 16 until it reaches a specified pressure. On the other hand, an auxiliary tank 13 is provided integrally with the expansion tank 10 at the top of the expansion tank 10 via a packing 15. Therefore, if the water level in the expansion tank 10 falls below the reference water level determined by the connecting pipe 14 due to a change in water temperature or natural evaporation, the nitrogen gas 12 in the space above the free surface in the expansion tank 10 will flow to the connecting pipe 1.
4 into the auxiliary tank 13. As a result, pure water 11 is replenished from the auxiliary tank 13 into the expansion tank 10, and a predetermined amount of water is maintained.

〔Effect of the invention〕

According to this invention, the structure of the expansion tank of the cooling water supply device is a pressureless sealed structure so that an inert gas is constantly supplied to the upper space above the free surface of the cooling water stored in the tank. Since the water does not come into direct contact with the atmosphere, the water quality of the cooling water is maintained, which not only prevents corrosion of the metal pipes that make up the cooling water circulation circuit and the contamination of harmful substances, but also assists in replenishing pure water at the top of the expansion tank. Since the tank is integrally provided, the decrease in cooling water in the expansion tank can be automatically compensated for.

[Brief explanation of the drawing]

Figures 1 and 2 show examples of the present invention; Figure 1 is an explanatory diagram showing the water level above the standard water level, and Figure 2 is an explanatory diagram showing the water level below the standard water level. 3 is a conventional cooling water circulation circuit diagram using an expansion tank, and FIG. 4 is an explanatory diagram showing a different conventional example. DESCRIPTION OF SYMBOLS 1... Cooling water circulation device, 2... Circuit, 3... Pump, 4... Heat radiator, 5... Cooled object, 6... Cooler, 7... Expansion tank, 8... Anaerobic plate, 10...
... Expansion tank, 11 ... Pure water, 12 ... Nitrogen gas, 13 ... Auxiliary tank, 14 ... Connection pipe,
15...Packing, 16...Check valve, 17...Float controller, 18...Gas cylinder, 19
...Adjuster, 20...Filter.

Claims (1)

[Claims] 1. A cooling system that sequentially incorporates a pump, a radiator, and a cooler in a cooling water circulation circuit, and further incorporates an expansion tank on the suction side of the pump that stores cooling water inside and leaves an upper space. In the water supply device, an auxiliary tank that fills the space above the free surface of the cooling water stored in the expansion tank with an inert gas so as to be constantly supplied, and that supplies pure water when the free surface falls below a reference water level. and a check valve capable of exhausting the inert gas to the outside of the expansion tank. 2. In what is stated in claim 1,
An expansion tank for a cooling water supply device, characterized in that the auxiliary tank is integrally provided at the top of the expansion tank and is configured to be able to replenish pure water by gravity. 3. The expansion tank of the cooling water supply device according to claim 1 or 2, wherein the inert gas is nitrogen gas.