JPS62213629A - Inner pressure control device for clean booth - Google Patents

Abstract

PURPOSE:To enable a stable pressure difference to be maintained between an inner pressure of a clean booth and an indoor pressure by a method wherein a pressure adjusting box to be connected via a first pressure control damper to a clean booth is allowed to communicate with a discharging means and further with an indoor part through a second pressure control damper. CONSTITUTION:An amount of air exceeding a volume of leakage within a clean booth flows into a spacing area within a pressure adjusting box 13 via a first relief damper 14. A spacing area within the box 13 communicates with a room 12 through a second relief damper 15 and the air within the box 13 is discharged to a duct 11 by a blower 10, so that the box 13 is kept at a lower inner pressure than that of the room 12 by an amount of set pressure of the damper 15. Under such a condition as above, if a set pressure P1 of the damper 14 is set slightly lower than a set pressure P2 of the damper 15, it is possible to keep the pressure within the clean room at a pressure a value of (P2-P1) higher than that in the room 12.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an internal pressure control device for a clean booth, and in particular, for example, maintains the internal pressure of a painting booth or the like at a constant pressure difference between the inside of the installation room and the inside of the booth. The present invention relates to an internal pressure control device for a clean booth, which is suitable for controlling a clean booth that prevents air from mixing with indoor air and performs high-quality painting.

[Conventional technology]

For example, in a lean booth, such as a paint booth used to perform high-quality painting, in order to keep the metal inside the clean booth clean, the pressure inside the clean booth is set higher than that of the installation chamber to prevent air from entering. This is dangerous because air containing solvents generated during interior painting work can leak into the room. Therefore, the pressure inside the clean booth cannot be made much higher than that inside the room, and must be controlled so that it is slightly higher.

A conventional internal pressure control device for a clean booth will be explained with reference to FIG.

FIG. 2 is a schematic configuration diagram of a conventional internal pressure control device for a clean booth.

In FIG. 2, 1 is a clean booth installed in the room 12, and 2 is the temperature and cleanliness inside this clean booth 1. Air conditioner for holding, 3 is outside air intake duct,
Reference numeral 4 denotes an outside air volume adjustment damper provided at the intake port of the air conditioner 2 of the outside air intake duct 3, and 5 represents an in-booth circulating air volume adjustment damper □ installed at the communication portion between the air conditioner 2 and the clean booth 1. The outside air intake duct 3 and the outside air amount adjustment damper 4 constitute a means for introducing outside air into the air conditioner 2, and the air conditioner 2 and the booth circulating air amount adjustment damper 5 constitute a means for introducing the outside air into the clean booth 1. It constitutes an air conditioner for purifying the air.

Reference numeral 6 indicates an air curtain device provided at an opening that serves as a communication passage between the clean booth 1 and the chamber 12; 7 indicates an air curtain blower; and 8 indicates a pressure control damper for maintaining the pressure within the clean booth 1. The relief damper 9 refers to an exhaust guide 1 provided to cover the relief damper 8.
0 is an exhaust blower, and 11 is an exhaust duct. The exhaust guide 9, the exhaust blower 10, and the exhaust duct 11 are used to discharge exhaust from the clean booth 1, such as air containing solvent generated during painting work, to the outside. It constitutes the exhaust means for. 12 is a room in which the clean booth 1 is installed.

In the conventional clean booth internal pressure control device with such a configuration, the clean booth 1 takes in air from outside via the air conditioner 2, and controls the outside air so that the internal pressure of the clean booth 1 is slightly higher than the inside of the room 12. It is adjusted by the opening degree of the amount adjusting damper 4.

In addition, since the differential pressure between the internal pressure of clean booth 1 and the internal pressure of chamber 1z changes due to the opening and closing of the door (not shown) of chamber 12, etc., a relief is installed so that the internal pressure of clean booth 1 can be maintained slightly higher than that of the room. Adjustment is made so that the exhaust is constantly exhausted from the clean booth 1 to the chamber 12 side via the damper 8.

The relief damper 8 controls the internal pressure of the clean booth 1 and the chamber 12.
The differential pressure between the internal pressure of the clean booth 1 and the internal pressure of the chamber 12 is kept constant by receiving the differential pressure between the damper in the opening direction and operating the weight in the closing direction in response. The set pressure is determined so that the pressure can be maintained.

In addition, as prior art information regarding pressure control in clean rooms, for example, Proceedings of the Japan Society for Air Conditioning and Hygiene (1
There is a research report titled "Pressure Control in Vertical Laminar Flow Clean Rooms" by Katsumi Hashi et al. (October 1984).

[Problem that the invention seeks to solve]

Conventionally, the pressure difference between the internal pressure of the clean booth 1 and the internal pressure of the chamber 12 is adjusted by a mechanism such as the relief damper 8, as described above, so that it is not affected by the friction of the rotating shaft or sliding part of the relief damper 8. In some cases, if the force applied to the relief damper is weak, it does not operate smoothly, and control becomes unstable in areas with low differential pressure.

Therefore, if the set pressure of the relief damper is increased to a certain extent and the pressure difference between the internal pressure of the clean booth 1 and the internal pressure of the chamber 12 increases to about 1 to 2 rtrrs H20, the air curtain device 6 installed at the opening of the clean booth 1 The airtight performance had to be improved by increasing the wind speed.

For this reason, the power of the air curtain blower 7 in the air curtain device 6 increases, and the airflow inside the clean booth 1 is disturbed by the high-speed air curtain flow, making it difficult to maintain the cleanliness inside the clean booth. There was a problem.

The above-mentioned report in the academic journal of the Japan Society for Air Conditioning and Hygiene is a research report in which two tests were conducted and analyzed on the airtightness and amount of outside air required for pressurization using a vertical laminar flow clean room. As with the present invention described in 1., technical means for minutely controlling the differential pressure between the internal pressure of the clean booth and the indoor pressure was not disclosed.

The present invention was made to solve the above-mentioned problems, and it stabilizes the differential pressure between the internal pressure of the clean booth and the indoor pressure with a minute pressure difference, and reduces the flow velocity of the air curtain at the opening of the clean booth. To provide an internal pressure control device for a clean booth that reduces turbulence of airflow within the clean booth and facilitates maintaining cleanliness within the clean booth.
That is the purpose.

[Means for solving problems]

In order to solve the above-mentioned problems, the configuration of the internal pressure control device for a clean booth according to the present invention includes a clean booth installed indoors, an air conditioner for purifying the air in the clean booth, and an air conditioner for purifying the air in the clean booth. means for introducing outside air into the air conditioner; an air curtain device provided at the opening of the clean booth; a pressure control damper for maintaining the pressure within the clean booth; In the clean booth internal pressure control device, the clean booth is provided with a pressure adjustment box connected to the clean booth via a first pressure control damper, and the pressure adjustment box is connected to the It communicates with the exhaust means and also communicates with the chamber via a second pressure control damper.

It should be noted that the internal pressure of the pressure adjustment box is
The first. Each set pressure of the second pressure control damper is set, and the set pressure of the first pressure control damper is set lower than the set pressure of the second pressure control damper. .

[Effect]

The operation of the above-mentioned technical means will now be described in accordance with the idea on which the present invention was developed.

In a relief damper related to a pressure control damper, when a certain force (static friction force) is exceeded, the damper opens and closes proportionally even to a small change in force. Therefore, in the present invention, paying attention to this, a pressure adjustment box that communicates with the interior of the room via the second relief damper is provided, and the second
The pressure inside the pressure adjustment box is adjusted to a pressure that allows the relief damper to operate smoothly, that is, lower than the indoor pressure, and the difference between the pressure inside the pressure adjustment box and the pressure inside the clean booth allows it to operate smoothly. Since the clean booth and the pressure adjustment box are connected through the first relief damper, stable pressure control can be achieved even when the differential pressure between the internal pressure of the clean booth and the indoor pressure is small. became.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a schematic configuration diagram of an internal pressure control device for a clean booth according to an embodiment of the present invention. In the figure, the same reference numerals as in FIG. The explanation will be omitted.

In FIG. 1, reference numeral 13 denotes a pressure adjustment box placed in the chamber 12 in which the clean booth 1 is installed, and one end of this pressure adjustment box 13 is connected to an exhaust blower 10. It communicates with exhaust means consisting of an exhaust duct 11.

14 is a first relief damper related to the first pressure control damper provided at the connection between the pressure adjustment box 13 and the clean booth 1; 15 is a first relief damper that connects the pressure adjustment box 13 and the chamber 12; This is a second relief damper related to the second pressure control damper provided in the communicating portion.

The pressure adjustment box 13 is configured such that its internal pressure is lower than the internal pressure of the clean booth 1 by the set pressure of the first relief damper 14 and lower than the internal pressure of the chamber 12 by the set pressure of the second relief damper 15. 1. The set pressures of the second relief dampers 14 and 15 are set, and the set pressure Pze of the first relief damper and the set pressure Pze of the second relief damper are set.
(The pressure is set slightly lower than the set pressure P2.

Function 2 of the clean booth internal pressure control device configured as described above will be explained.

Originally, it is desired that the internal pressure in the clean booth 1 is slightly higher than the internal pressure in the chamber 12 to prevent air from entering the chamber 12.

Therefore, the outside air amount adjustment damper 4 is adjusted so as to constantly replenish the amount of air slightly larger than the amount of air leaking from the air curtain device 6 etc. provided at the opening, and the outside air is introduced into the air conditioner 2 through the outside air intake duct 3. , the clean booth 1 by the air conditioner 2 and the damper 5 for adjusting the amount of circulating air in the booth.
Circulate and purify the inside.

The amount of air inside the clean booth that exceeds the leakage amount is
Pressure adjustment box 13 via relief damper 14 of
It flows into the inner space area.

The spatial region of this pressure adjustment box 13 communicates with the inside of the chamber 12 via the second relief damper 151r.
In addition, the air in the pressure adjustment box 13 is supplied to the exhaust blower 1.
0 to the exhaust duct 11, the pressure adjustment box 13 is maintained at an internal pressure lower than the internal pressure of the chamber 12 by the set pressure of the second relief damper 15.

In such a state, the set pressure Pl of the first relief damper 14 is changed to the set pressure P2 of the second relief damper 15.
If it is set slightly lower, the internal pressure of clean booth 1 will be lower than the internal pressure of chamber 12 by P2 Pt, that is, both I
It is possible to increase the pressure by the difference in the set pressure of the J IJ-fu damper.

In other words, the first. While setting the set pressures p, p2 of the second relief dampers 14, 15 to relatively large differential pressures that allow smooth operation of the respective relief dampers, the difference between the set pressures of both relief dampers is Since Pi Pt determines the pressure difference between the pressure inside the clean booth 1 and the pressure inside the chamber 12, the inside of the clean booth 1 and the inside of the chamber 12 can be smoothly controlled with a small pressure difference.

According to this embodiment, the differential pressure between the internal pressure of the clean booth 1 and the internal pressure of the chamber 12 can be controlled by a minute differential pressure of 0.2 to 0.5 DH! The air inside the clean booth 1 is almost never leaked into the room 12, and the safety of clean booths such as painting booths using solvents is increased.

In addition, since the pressure inside the clean booth 1, which must be made airtight with the air curtain device 6, etc., becomes appropriate, the flow velocity of the air curtain can be lowered, and the clean booth 1
Disturbance of the airflow inside the clean booth 1 is reduced, therefore, the cleanliness inside the clean booth 1 can be easily maintained, and the power of the air curtain blower 7 is also reduced.

Furthermore, the pressure adjustment box 13 is separated from the inside of the chamber 12 by a second
IJ IJ-Full damper 15 only communicates,
It constitutes a spatial region independent from the chamber 12, and since the solvent gas generated in the clean gas 1 can be exhausted through the exhaust duct 11, leakage of the solvent gas into the chamber 12 can be prevented.

〔Effect of the invention〕

As described above, according to the present invention, the differential pressure between the internal pressure of the clean booth and the indoor pressure is stabilized by a minute pressure difference, and the flow velocity of the air curtain at the opening of the clean booth is reduced, so that the pressure difference between the internal pressure and the indoor pressure is stabilized. It is possible to provide an internal pressure control device for a clean booth that reduces turbulence of airflow within the booth and facilitates maintenance of cleanliness within the clean booth.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an internal pressure control device for a clean booth according to an embodiment of the present invention, and FIG. 2 is a schematic configuration diagram of a conventional internal pressure control device for a clean booth. 1...Clean booth, 2...Air conditioner, 3...
・Outside air intake duct, 4...Outside air volume adjustment damper, 6.
...Air curtain device, 10...Exhaust blower, 11.
... Exhaust duct, 12... Chamber, 13... Pressure adjustment box, 14... First relief damper, 15...
・Second lily (f 711hl λ 1st country 3-1 outside air η side to east guttato 4・-outside air amount m set turn l zo 6--1 ebucar line 4'' 1 70-Sakaki air, ta * n -#Viewing duct/Z--・Sparrow/3-, the power steel is desired PPl hotawas, 迤~1a relief stop 2 ts-11z's relief ``reno'' 2nd- mouth

Claims (1)

[Claims] 1. A clean booth installed indoors, an air conditioner for purifying the air in the clean booth, a means for introducing outside air into the air conditioner, and an opening of the clean booth. internal pressure control of a clean booth, comprising: an air curtain device installed in the clean booth; a pressure control damper for maintaining the pressure within the clean booth; and an exhaust means for discharging exhaust gas from the clean booth to the outside. In the apparatus, a pressure adjustment box is provided that is connected to the clean booth via a first pressure control damper, and the pressure adjustment box is communicated with the exhaust means and is connected to the clean booth via a second pressure control damper. An internal pressure control device for a clean booth, characterized in that the internal pressure control device is configured to communicate with the interior of the room. 2. In the product described in claim 1, the pressure regulating box has an internal pressure that is lower than the clean booth internal pressure by the set pressure of the first pressure controlling damper, and the pressure regulating box is lower than the clean booth internal pressure by the set pressure of the first pressure controlling damper. The set pressures of the first and second pressure control dampers are set so that the set pressure is lower than the indoor pressure, and the set pressure of the first pressure control damper is set to be lower than the indoor pressure by the set pressure. A clean booth internal pressure control device that sets the pressure lower than the set pressure of the pressure control damper.