JPH0463291B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an absolute pressure control device, and in particular, to a device for controlling absolute pressure so that the absolute pressure in a chamber to be controlled is precisely controlled to a set pressure even if the atmospheric pressure fluctuates. This invention relates to an absolute pressure control device.

[Prior Art] Recently, in many fields including the semiconductor industry, precision positioning devices equipped with optical length measuring devices are often used. In a room where an optical length measuring device is installed, when the atmospheric pressure changes, the air density changes, and as a result, the refractive index of the air in the length measuring space changes, making it difficult to perform precise positioning using the length measuring device. Therefore, the absolute pressure in the chamber in which the precision positioning device equipped with the optical length measuring device is installed must be controlled to be constant.

Conventionally, devices that perform absolute pressure control include:
An apparatus having a configuration as shown in FIG. 3 is employed. In FIG. 3, an outside air conditioner 1, an outside air fan 2, and a constant air volume valve 3 are connected in order, and a constant air volume of outside air is supplied to the air conditioner 4 through the outside air conditioner 1, outside air fan 2, and constant air volume valve 3. We are trying to supply it.
The air conditioner 4 takes in return air from the absolute pressure controlled room 5 via the constant air volume valve 6, thereby always supplying a constant amount of air to the controlled room 5.

On the other hand, the absolute pressure in the controlled chamber 5 is determined by the absolute pressure gauge 7.
The opening degree of the pressure regulating valve 9 is adjusted by the indicating controller 8 based on this detected value. and,
By controlling the amount of exhaust air from the controlled chamber 5 and exhausting the air outside from the exhaust fan 10, the absolute pressure inside the controlled chamber 5 is controlled to the set value.

[Problem that the invention seeks to solve]

However, in the absolute pressure control device configured as described above, fluctuations in atmospheric pressure when high and low pressures pass through directly affect the chamber 5 to be controlled. Therefore, when the atmospheric pressure fluctuates greatly, the control accuracy will be ± as shown in Figure 4.
2.0 mbar, which caused the problem that the absolute pressure inside the controlled chamber 5 could not be controlled with the precision required by the precision positioning device.

SUMMARY OF THE INVENTION An object of the present invention was made in view of the above-mentioned drawbacks, and it is an object of the present invention to provide an absolute pressure control device that can accurately control the absolute pressure within a chamber to be controlled even when atmospheric pressure fluctuates greatly.

[Means for solving problems]

In order to achieve the above object, the present invention provides a supply means for supplying outside air into a chamber to be controlled, an absolute pressure gauge for detecting the pressure in the chamber to be controlled, and a pressure meter to the exhaust side based on a signal from the absolute pressure gauge. Absolute pressure system equipped with an indicating controller that adjusts the opening degree of the installed pressure control valve so that the pressure in the controlled chamber reaches the set pressure, and an exhaust fan that exhausts the air in the controlled chamber to the outside. In the control device, the control target chamber is covered with a controlled relaxation chamber, and an absolute pressure gauge detects the pressure inside the controlled relaxation chamber, and a pressure regulating valve provided on the exhaust side based on a signal of the absolute pressure gauge. The structure includes an indicator controller that adjusts the opening degree so that the pressure inside the control relaxation chamber reaches a set pressure, and an exhaust fan that exhausts the air inside the control relaxation chamber to the outside.

[Effect]

In this way, in the present invention, since the controlled relaxation chamber surrounds the controlled room, fluctuations in atmospheric pressure do not have a direct effect on the controlled room. Absolute pressure within the controlled room can be precisely controlled regardless of atmospheric pressure fluctuations.

〔Example〕

Hereinafter, details of the present invention will be explained using examples shown in the drawings.

FIG. 1 is a schematic configuration diagram showing an embodiment of an absolute pressure control device according to the present invention, and the same parts as in FIG. 3 are given the same reference numerals. An absolute pressure gauge 7 for detecting the pressure within the controlled chamber 5 is disposed in the controlled chamber 5, and the absolute pressure gauge 7 is connected to a pressure regulating valve 9 via an indicating controller 8. .
The indicating controller 8 receives a signal from the absolute pressure gauge 7 and adjusts the opening degree of the pressure regulating valve 9 so that the pressure in the controlled chamber becomes a set pressure. Furthermore, an exhaust fan 10 is provided on the downstream side of the pressure regulating valve 9 to exhaust the air inside the controlled chamber 5 to the outside. On the other hand, an air conditioner 4 is connected to the control target room 5, and constant air volume valves 6 and 11 are connected to the upstream side of the air conditioner 4. Therefore, a constant amount of outside air is supplied to the air conditioner 4. In addition, the air conditioner 4 takes in return air from the controlled room 5 through the other constant air volume valve 6.
A constant amount of air is always supplied to the controlled room 5.

The above configuration is the same as the conventional configuration, but in this embodiment, the control target chamber 5 is covered with the control relaxation chamber 12. An outside air fan 2 is connected to this controlled relaxation chamber 12 via an outside air conditioner 1, and by passing through a constant air volume valve 3, it is possible to always supply a constant amount of air into the controlled relaxation chamber 12. ing. Further, in the control chamber 12, there is an absolute pressure gauge 1 for detecting the pressure inside the control chamber 12.
3 is arranged, and the absolute pressure gauge 13 is connected to a pressure regulating valve 15 via an indicating regulator 14. The indicating regulator 14 receives a signal from the absolute pressure gauge 13 and adjusts the valve opening of the pressure regulator 15 provided on the exhaust side so that the pressure in the control relaxation chamber becomes the set pressure. It's summery. Further, an exhaust fan 16 is connected to the downstream side of the pressure regulating valve 15 for exhausting the air inside the control relaxation chamber 12 to the outside.

Next, the operation of the absolute pressure control device configured as above will be explained. First, control relaxation room 1
2, outside air is sent to the outside air conditioner 1 and the outside air fan 2, and by passing through the constant air volume valve 3, a constant amount of air is always supplied into the controlled relaxation chamber 12. It's becoming like that. On the other hand, the absolute pressure in the control relaxation chamber 12 is detected by the absolute pressure gauge 13, the opening degree of the pressure control valve 15 is adjusted by the indication control valve 14, and the exhaust is exhausted outside the room from the exhaust fan 16, thereby controlling the relaxation chamber 12. The absolute pressure within chamber 12 is controlled to be somewhat constant.

Furthermore, air from the control relaxation chamber 12 is supplied to the controlled room 5 via the constant air volume valve 11, and return air from the controlled room 5 is supplied from the air conditioner 4 via the constant air volume valve 6. A constant amount of air is always supplied.
On the other hand, the absolute pressure inside the control target chamber 5 is detected by an absolute pressure gauge 7, and based on the detected value, an indicating controller 8
The opening degree of the pressure regulating valve 9 is adjusted by
The amount of exhaust gas inside is controlled. Thereby, the absolute pressure within the controlled chamber 5 is precisely controlled to the set value.

According to the absolute pressure control device configured as described above, even if the atmospheric pressure fluctuates greatly when high or low pressure passes, the
Absolute pressure can be precisely measured with an accuracy of bar.

In addition, in the embodiment described above, the control target room 5
Although the configuration is such that the chamber 5 to be controlled is covered by the control relaxation chamber 12 having a single-chamber structure, the present invention is not limited to this, and the control target chamber 5 may be covered by the control relaxation chamber 12 having a multi-chamber structure.

〔Effect of the invention〕

As explained above, according to the present invention, since the room to be controlled is covered with the control room, fluctuations in atmospheric pressure do not directly affect the room to be controlled. This has the excellent effect of precisely controlling the absolute pressure within the chamber to be controlled, regardless of the

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of an absolute pressure control device according to the present invention, FIG. 2 is a diagram showing absolute pressure control results by the device of the present invention, and FIG. 3 is an example of a conventional absolute pressure control device. FIG. 4 is a diagram showing the absolute pressure control results by the apparatus shown in FIG. 3. 3... Constant air volume valve, 4... Air conditioner, 5... Controlled room, 6... Constant air volume valve, 7... Absolute pressure gauge, 8...
... Indicating controller, 9... Pressure regulating valve, 10... Exhaust fan, 11... Constant air volume valve, 12... Control relaxation chamber, 13... Absolute pressure gauge, 14... Indicating regulating valve,
15...Pressure control valve, 16...Exhaust fan.

Claims (1)

[Claims] 1. A supply means for supplying outside air into the room to be controlled;
an absolute pressure gauge that detects the pressure within the controlled chamber;
An indicator controller that adjusts the opening degree of a pressure regulating valve provided on the exhaust side based on the signal from the absolute pressure gauge so that the pressure in the controlled chamber reaches a set pressure; In an absolute pressure control device equipped with an exhaust fan that exhausts the air to the outside, the chamber to be controlled is covered with a controlled relaxation chamber, and an absolute pressure gauge that detects the pressure inside the controlled relaxation chamber is based on a signal of the absolute pressure gauge. an indicating controller that adjusts the opening degree of a pressure regulating valve provided on the exhaust side so that the pressure in the control relaxation chamber reaches a set pressure; and an exhaust fan that exhausts the air in the control relaxation chamber to the outside. An absolute pressure control device characterized by being provided with.