JPS6240372A - Evacuation pump system for continuous vacuum deposition device - Google Patents

Abstract

PURPOSE:To eliminate the entry of oil into a circulating gas and to form satisfactory environment for vapor deposition in the stage of executing differential evacuation with an evacuation pump system by setting the pressures of respective stages and adopting vacuum pumps meeting such pressures. CONSTITUTION:A strip 10 subjected to a pretreatment is introduced via sealing devices 1 connected in multiple stages from an upper stream side A into a vacuum vapor deposition chamber 2 where the strip is subjected to vapor deposition. The strip is then taken out via the sealing devices 1 formed in multiple stages to a down stream side B. Ducts 11 are respectively provided to the many sealing devices 1 to execute differential evacuation so that the degrees of vacuum are gradually increased on the upper stream side A and are successively decreased on the down stream side B. Water sealing type vacuum pumps 6 are used down to 50mmTorr of the low vacuum stage or below in the above-mentioned constitution. A mechanical booster pump 5 is used in the front stage and a water sealing type pump 6 is used for the rear stage in the middle vacuum stage from low vacuum stage 50mmTorr to 10<-3>Torr or below. The intrusion of the oil into the circulating gas is thereby prevented and the desired vacuum evacuation is made possible, by which good environment for vapor deposition is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an exhaust pump system in which specific exhaust pumps are selectively arranged, which is applied to the exhaust system of a continuous vacuum deposition apparatus.

(Prior Art) FIG. 2 shows an example of pressure values in differentially evacuated chambers in a conventional continuous vacuum evaporation apparatus (Siegfried Schiller, "Vacuum Deposition", Agne Publishing, P135). Although the vacuum pump used is unknown in the figure, it is assumed that it has the following configuration.

In other words, the operating pressure of a vacuum pump is one that has been widely known for a long time, as shown in Figure 3 (Vacuum Pump, Nikkan Kogyo Shimbun, P2O9), and these are combined to form an exhaust system. It is easy to guess what will happen. For the pumps shown in Figure 2 (]]], enter the pump name that can be estimated from the characteristics in Figure 3.The operating pressure range is usually low vacuum, medium and high vacuum. This is because it is common knowledge that a wide oil rotary pump is used.

As shown in FIG. 4, the principle of an oil rotary pump is that the cylinder and valve portion of the pump are immersed in oil in an oil tank to prevent outside air from entering.

For this reason, it is known that oil mist is scattered outside the exhaust system and is entrained in the exhaust gas.

In fact, when a large amount of gas is exhausted, such as in a continuous vacuum line in a continuous vacuum evaporation device, an inert gas is used to prevent oxidation of the strip, so the exhaust gas must be circulated using a purification device. In this case, oil mist is mixed into the exhaust gas, and a device for treating the oil mist is required in the purification device. However, 1. It is very difficult to completely remove the Ura mist, and if the Ura mist is not removed and is supplied in circulation, it will contaminate the object to be vaporized in the vapor deposition equipment, resulting in poor vapor deposition adhesion. Furthermore, oil diffusion pumps exhaust oil vapor in the form of jets, and oil contamination is still a problem.

(Problems to be Solved by the Invention) As described above, in the conventional continuous vacuum equipment line using an oil-based vacuum pump, when an exhaust gas circulation system is adopted, oil tends to get mixed into the exhaust gas. Therefore, an additional oil removal device is required, but even with this device, it is difficult to completely remove the oil, which causes a decrease in vapor deposition performance. Although the oil removal device is originally redundant equipment, there is a problem in that equipment costs and maintenance costs are increased in order to replace it and improve its performance.

The present invention was made to solve these problems.
The present invention aims to provide an exhaust pump system for a continuous vacuum evaporation apparatus in which the pressure of each stage is set without using an oil-based vacuum pump when differential evacuation is performed, and a vacuum pump corresponding to the pressure is set.

(Means for Solving the Problem) Therefore, in the present invention, as a first invention, a sealing device is connected in multiple stages from an atmospheric pressure chamber to a vapor deposition chamber, and a number of exhaust chambers are provided, and piping is provided for performing differential exhaust. In the exhaust pump system for a continuous vacuum evaporation apparatus, which consists of connecting a
In the medium vacuum stage from 2 Torr to less than 103 Torr, a mechanical booster pump is used as the first stage, a wet roots blower or a water ring pump is used as the second stage pump, and the second stage pump is used as the second stage pump.
The second invention relates to an exhaust pump system for a continuous vacuum evaporation apparatus, which has a configuration in which a sealing device is connected in multiple stages from an atmospheric pressure chamber to a evaporation chamber, and a number of exhaust chambers are provided, and piping for differential exhaust is connected to each chamber. , 50 ++ nTo of the low vacuum stage
Use a wet roots blower or a water ring vacuum pump to reduce the temperature from 5 Q * mTorr to 10 mTorr.
For medium vacuum stages up to -3Torr, a mechanical booster pump is used in the first stage, a wet roots blower or a water ring pump is used as the latter stage pump, and a 10-3Torr
In the high vacuum stage below rr, a turbo molecular pump is placed in the front stage,
A mechanical booster pump is used in the subsequent stage, and a wet roots blower or a water ring pump is used in the subsequent stage, respectively, as a means of solving the above problems.

(Function) Since water-based pumps are used for the low, medium, and high vacuum stages, only moisture is contained in the gas on the inlet side of the exhaust gas circulation purification system, and this moisture is removed by the dehumidifier. It can be easily removed by operation, and the water content in the gas can be kept sufficiently low on the outflow side of the purification system.

(Example) Below, an example of the present invention will be described with reference to the drawings.
The figure shows an embodiment in which the exhaust system of the present invention is employed in the exhaust system of a continuous vacuum deposition line for strips.

This embodiment shows an example in which a mechanical booster pump 7 is used in the first stage and a water ring pump 6 is used in the second stage in order to perform vapor deposition in a medium vacuum region.

If vapor deposition is to be performed in a high vacuum region, a turbo molecular pump may be installed in front of the mechanical booster pump 7 section.

10 is a strip which is the object to be processed; strip 1
0 is pretreated and supplied from the upstream side A. Upstream A
Since it is at atmospheric pressure, it is necessary to exhaust the air to the pressure of the vapor deposition chamber 2, which is a vacuum processing chamber, and after vapor deposition, it is generally vented to the downstream side B (atmospheric pressure).

For this reason, since the inlet and outlet sides of the strip 10 are under atmospheric pressure, the sealing devices 1 are strung up in multiple stages in the vapor deposition line up to the vacuum processing pressure, and each sealing device 1 is formed between each sealing device 1. It is necessary to perform evacuation with a vacuum evacuation pump via the duct 11 leading to the evacuation chamber.

In this embodiment, the pressure setting of each exhaust chamber is 76 mm from the upstream side.
0Torr, 200Torr, 70Torr, 1
The degree of vacuum is increased sequentially to 0 Torr, I Torr, and 10-' Torr, so that the pressure in the vacuum deposition chamber 2 containing the vacuum evaporation apparatus will finally reach 10' Torr. The vacuum pump used is a wet roots blower for 200 Torr, a water ring vacuum pump for 70 Torr, and a 1Q vacuum pump.
Below Torr, a mechanical booster pump and a water ring pump are used together. When it is necessary to achieve a higher degree of vacuum, that is, to lower the vacuum to 10 -3 Torr or less, a turbo molecular pump is used in the first stage, followed by a mechanical booster pump, followed by a wet roots blower or a water ring pump. After passing through the pump, the exhaust gas is pressurized to atmospheric pressure conditions.

A dehumidification device 9 is provided in the exhaust gas purification device that is used for circulation. The exhausted gas is again supplied to the upstream side A and the downstream side B of the vapor deposition line via the duct 12.

As the sealing device 1, for example, a known sealing device consisting of a pair of sealing rolls R as shown in FIG. 5 is used.

With the above configuration, it was possible to obtain a dew point of the exhaust gas on the exit side of the purifier at -70°C or less.

(Effects of the invention) As explained above in detail, according to the present invention, the exhaust gas in each exhaust chamber is sent to the circulating gas purification device through only a water-based pump, and a dehumidification device is installed in the purification device. It is something. Therefore, only moisture is mixed in the exhaust gas, and the moisture content in the circulating gas after passing through the purification device can be reduced to a level that poses no problem for, for example, continuous vacuum evaporation.

Therefore, according to the present invention, there is no mixing of oil into the circulating gas due to the use of pumps in the system as in the past, and it is possible to fundamentally eliminate the need for devices to remove oil and the consumption of expensive oil. However, it is possible to perform desired vacuum evacuation and create a favorable vapor deposition environment.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing a pump system of a continuous vacuum evaporation apparatus according to an embodiment of the present invention, Fig. 2 is a schematic sectional view of a conventional continuous vacuum apparatus, and Fig. 3 is a line showing the operating pressure range of the vacuum pump. FIG. 4 is a sectional view of a conventional partial pump, and FIG. 5 is a sectional view showing an example of a sealing device. Explanation of the main parts of the diagram ■ - Sealing device 2 - Vacuum processing chamber (evaporation chamber) 3.4 - Water pump (low vacuum) 5 - Mechanical booster pump 6 - Water ring vacuum pump 9 - -Moisture insufflation device S5-〃,-1 Figure 3 Figure 4 Figure 5

Claims (2)

[Claims] (1) In an exhaust pump system for a continuous vacuum evaporation apparatus, the sealing device is connected in multiple stages from the atmospheric pressure chamber to the evaporation chamber, and a number of exhaust chambers are provided, and piping for differential exhaust is connected to each chamber. For low vacuum stages below 50mmTorr, use a wet roots blower or water ring vacuum pump.
In the low vacuum stage from 50 mm Torr to less than 10^-^3 Torr, a mechanical booster pump is used in the first stage, and a wet roots blower or water ring pump is used as the second stage pump. Exhaust for continuous vacuum evaporation equipment. Pump system. (2) In an exhaust pump system for a continuous vacuum evaporation apparatus, the sealing device is connected in multiple stages from the atmospheric pressure chamber to the evaporation chamber, and a number of exhaust chambers are provided, and piping for differential exhaust is connected to each chamber. For low vacuum stages below 50mmTorr, use a wet roots blower or water ring vacuum pump.
For medium vacuum stages from 50 mm Torr to less than 10^-^3 Torr, a mechanical booster pump is used in the front stage, and a wet roots blower or water ring pump is used as the latter stage pump, and furthermore, for low vacuum stages from 50 mm Torr to below 10^-^3 Torr, In the high vacuum stage, an exhaust pump system for continuous vacuum evaporation equipment is characterized by using a turbo molecular pump in the first stage, a mechanical booster pump in the second stage, and a wet roots blower or water ring pump in the second stage.