JPH04139345A - Method and apparatus for supplying constant temperature and constant moisture air - Google Patents

Abstract

PURPOSE:To supply stable constant temperature and constant moisture air in a high accuracy by primarily heating cooled dehumidified air to a predetermined temperature lower than a target temperature to raise its temperature, then secondarily heating the primarily heated air to the target temperature, and supplying it. CONSTITUTION:When the atmospheric air introduced by a blower 4 is humidified by a humidifier 5 and then passed through a cooler 7, it is cooled to be dehumidified to a temperature corresponding to the dew point of the air having temperature, moisture conditions requested in an object space 40. The air passed through the cooler 7 is heated to an intermediate predetermined temperature to a target temperature such as a predetermined temperature higher by 3-6 degrees than the temperature of the dew point by a primary heater 8. The thus primarily heated air is introduced to a secondary heater 15 at the intermediate of a hose duct, secondarily heated so that the temperature of an air supply port 18 becomes the target temperature, and supplied as the air having target temperature and moisture conditions to the object space.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a method for determining the temperature of the air to be supplied,
The present invention relates to an air treatment method capable of controlling humidity and an apparatus for performing this method.

Conventional technology In the semiconductor manufacturing, biotechnology, pharmaceutical and food manufacturing, medical fields, etc., fresh, constant temperature,
Humidity-regulated and clean air is often required.

For example, when manufacturing an IC, when etching an IC pattern on the silicon wafer 7r, a resist solution is applied on the oxide film formed on the surface of the silicon wafer 77.
After drying the resist, it is exposed to light using a 7-otomask to expose the resist film to light. The thickness of the Rennost film formed at this time is approximately 100 angstroms, and the uniformity of the film greatly affects the final puddle of the product. The fluctuation range of temperature and humidity is
It is strongly desired that the respective values fall within a range of approximately ±0.1” C1 ±1% RH.

Conventionally, a constant temperature and constant humidity air supply device used for this type of application has a partition plate 51 inside a box body 50, as shown in FIG.
By partitioning the air, a series of air flow paths from the outside air inlet 52 to the hose duct connection port 53 is formed. Next to the outside air inlet 52, an evaporative humidifier 55, an air cooler 57 consisting of an evaporator of a refrigerator 56, and an electric heater 58 are installed in this order from the windward side to the leeward side. It is provided for. 61 is a temperature sensor whose output is sent to the temperature controller 60
The heater 58 is controlled so that the desired air temperature is obtained. Similarly, 63 is a humidity sensor, and the humidity controller 62 is configured to control the operation of the heater 55a of the humidifier 55 based on its detection signal.

Reference numeral 65 is a hose duct, which is provided for the purpose of freely connecting the Jl air supply space 70 such as a clean bench and the constant temperature and humidity air supply device main body.
A length of about 15 m is used. 66 is an air filter such as an IIEP^ filter provided at the end of the hose duct.

When air is supplied under predetermined conditions using the above-mentioned device, the control temperature may fluctuate by more than ±0.4°C due to fluctuations in the temperature of the outside air, heat intrusion from the surroundings of the hose duct, etc. The temperature/humidity sensors 61, 63 are installed in order to eliminate the influence of heat entering from around the hose duct.
Even if it is attached to the air supply port 67, the fluctuation range is slightly
Although it became narrower, it was not possible to keep the fluctuation within ±0.1°C.

Structure of the Invention As a result of investigating the causes of such control disturbances, the inventor found that the control system is unable to follow changes in outside temperature, resulting in delayed response, and Long hose ducts, IIEP^ filters, etc. have considerable heat capacity, and this can be used as a heat source or heat absorption source.
The present invention was completed based on the discovery that the main factor is that the temperature of the air flowing through the air changes until a new equilibrium state is reached.

The gist of the present invention is to provide a method for supplying constant temperature and constant humidity air under predetermined conditions by providing a humidifier and a heater in a series of air flow paths connecting an air inlet and an air supply port, and passing outside air through the air flow path to supply constant temperature and humidity air under predetermined conditions. The outside air introduced into the flow path is humidified as necessary depending on the condition of the outside air, and then cooled and dehumidified to a temperature corresponding to the dew point of the air with the target temperature and humidity conditions.
Next, this cooled dehumidified air is primarily heated to a predetermined temperature lower than the target temperature to raise the temperature, and then this primary heated air is further heated to raise the temperature to the target temperature before being supplied. Patented method for supplying humid air, and vcI to improve this method! As for the air blower, there is a humidifier in the air flow path, and a cooling device that cools and dehumidifies the air that has passed through the humidifier to the dew point temperature of the air that has the target temperature and humidity conditions of the supplied air. a primary heater that heats the air cooled by the cooler to a predetermined temperature lower than the target value of the supply air; and a primary heater that further heats the air whose temperature has been raised by the primary heater to increase the temperature of the supply air. and a secondary heater to ensure that the air reaches the target temperature accurately.

Hereinafter, embodiments will be described in detail with reference to the drawings.

FIG. 1 conceptually shows an embodiment of the present invention, in which the inside of a box 1 configured with heat-insulating walls is divided by partition plates 1a and la, and a hose duct is connected from an outside air inlet 2 to a hose duct. A series of air flow paths leading to the connection port 3 are formed, and a 1ft4 air blower is attached to the outside air inlet 2 to continuously blow air from the outside air inlet toward the hose duct connection port, with the direction from the windward side to the leeward side. Therefore, an evaporative humidifier 5, a cooler 7 consisting of an evaporator of the frozen fi 6, and an electric primary heater 8 are provided in this order. Reference numeral 9 denotes a temperature sensor, and its detection signal is input to a temperature controller 10, where it is compared with a set value and the primary heater 8 is driven based on the deviation.

Reference numeral 11.11 denotes a hose duct, one end of which is connected to the hose duct connection port 3, and the other end is an air supply port 13 connected to the target space 40 via the FIEP filter 12. Reference numeral 14 denotes a heater storage duct case interposed in the middle of the hose duct 11. A secondary heater 15 is stored in this duct case, and its operation is controlled by the air supply port 1.
It is controlled by a temperature controller 17 based on a detection signal from a temperature sensor 16 provided at 3. A humidity sensor 18 is installed in parallel with the temperature sensor 17, and controls the heater 5a of the humidifier 5 through the controller 19. 20 is a level switch that detects the water level of the humidifier, and controls the water supply valve 22 that supplies water to the f-heat tank 21. 23 is a drain discharge pipe of the cooler 7. An example of the method of the present invention will be explained below along with the operation of the above device.

The above device humidifies outside air introduced by a blower 4 by a humidifier 5, and then when passing through a cooler 7,
In the target space 40, the air is cooled and dehumidified to a temperature corresponding to the dew point of the air with the temperature and humidity conditions required for FC. Thus, the absolute moisture content of the air that has passed through the cooler 7 is constant regardless of the air temperature, and therefore the air supply port 16
In this case, when the temperature of the supplied air reaches the target temperature required in the target space 40, the phase N humidity also becomes the target humidity and is supplied.

The air that has passed through the cooler 7 is heated to a predetermined temperature midway between the target temperature and the dew point temperature by a primary heater 8.
It is heated to a constant temperature of ~6 degrees higher. Was it primarily heated in this way? The air enters the secondary heater in the middle of the hose duct, where it is secondary heated so that the temperature at the air supply port 18 reaches the target humidity, and is supplied to the target space as air with the target temperature and humidity conditions. .

In the above embodiment, an example was shown in which heaters were provided at two locations as the primary and secondary heaters, but this does not negate the necessity of a tertiary heater.

Effects The constant temperature and humidity air supply method and device according to the present invention are as follows:
The primary heater can quickly react to fluctuations in the temperature conditions of the outside air and keep the temperature of the primary heated air accurately constant. Since it is only necessary to control the fluctuations in the intrusion heat of - You can do 1-re to be able to hate the world. The present inventor used the device shown in FIG. 1 and the device shown in FIG. Figure 3 shows the measurement results of temperature fluctuations at points A-D in Figures 1 and 2 in an experiment conducted with a machine of 800 VA, a blower of 200 W, target control temperature, and humidity of 23°C and 45% RH, respectively. From this result, this
It is clear that the temperature of the apparatus is precisely controlled within the range of ±0.1°C. Figure 1 is an explanatory diagram showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing the prior art.

FIG. 3 is a graph showing the results of a comparative experiment between the device of the present invention and the conventional device.

No. figure

Claims (3)

[Claims] (1) A method in which a series of air channels connecting an air inlet and an air supply port is provided with a humidifier and a heater, and outside air is passed through the air channels to supply constant temperature and constant humidity air under predetermined conditions to the air channels. After humidifying the introduced outside air as necessary, it is cooled and dehumidified to a temperature corresponding to the dew point of the air with the target temperature and humidity conditions, and then this cooled and dehumidified air is primarily heated to a predetermined temperature lower than the target temperature. A method for supplying constant-temperature and constant-humidity air, the method comprising: heating the primarily heated air to raise the temperature, and then heating the primarily heated air to raise the temperature to a target temperature before supplying the air. (2) a humidifier in a series of air channels equipped with a blower;
A cooler that cools and dehumidifies the air that has passed through the humidifier to a temperature corresponding to the dew point of the air with the target temperature and humidity conditions of the air to be supplied; Constant temperature and humidity air characterized by being provided with a primary heater that heats the air to a predetermined temperature lower than the target temperature of the air, and a secondary heater that further heats the air that has passed through the primary heater to the target temperature. Feeding device. (3) The air flow path connects a series of continuous spaces from the outside air inlet to the hose duct connection port, which are formed by partitioning the inside of the box-like structure with partition plates, and the hose duct connection port at one end. A humidifier, a cooler, and a primary heater are housed in the air passage in the box-like structure, and a secondary heater is a hose duct whose other end serves as a regulated air supply port. A constant temperature and constant humidity air supply device according to claim 2, which is installed in a constant temperature and constant humidity air supply device.