JPH07174360A - Operating method of air conditioner - Google Patents

Abstract

PURPOSE:To omit unnecessary operation from among heating, cooling and heating operations to save energy and reduce running costs by performing heating operation when cooling operation is performed and the absolute humidity drops to the absolute humidity of conditioned air. CONSTITUTION:In the case the absolute humidity is higher than conditioned air, a humidifying water supply valve 9 is closed and humidifying operation is not performed, and a cooling water supply valve 5 is opened to supply cooling water to perform cooling operation. The temperature and humidity of air after passing through a cooler 5 are detected by a temperature/humidity sensor TH2 to detect the absolute humidity, and the valve lift of the cooling water supply valve 11 at this time is fed back and selected so that the absolute humidity detected becomes equal to that of conditioned air. For example, when the surface temperature of the cooler 5 is set at a temperature below the dew point of conditioned air, the absolute humidity becomes equal to the absolute humidity of conditioned air and the temperature becomes lower than the set temperature of conditioned air. Then, a steam supply valve 13 is opened and steam is supplied to a heater 6 to heat air up to the set temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner whose temperature and humidity are adjusted to a predetermined temperature and humidity so that the paint can be applied under the same conditions while maintaining a constant atmosphere temperature and humidity in the coating booth. The present invention relates to a method of operating an air conditioner that sends air into a coating booth.

[0002]

2. Description of the Related Art An air conditioner for supplying air-conditioned air obtained by adjusting the temperature and humidity of outside air to a painting booth, etc. A cooler that cools down to the temperature and a heater that heats up to a predetermined temperature are installed. By operating these washers, coolers, and heaters, the temperature and humidity are adjusted to a preset temperature and humidity. .

In this case, conventionally, the temperature of the outside air
Regardless of the humidity, the temperature and humidity are controlled by three operations: humidification to the saturated state, maintaining the saturated state, heating or cooling to the dew point temperature of the conditioned air, and heating to the set temperature. For example, in the air diagram of FIG. 4, the condition of the conditioned air is P ₀ (temperature 25 ° C., relative humidity 85% RH, absolute humidity 0.017 kg / kg)
When set to, the area A indicates that the absolute humidity is higher than that of the conditioned air, and the area B indicates that the absolute humidity is lower than that of the conditioned air.
Further, the enthalpy is higher than the conditioned air, and the region C shows a state where the absolute humidity is lower than the conditioned air and the enthalpy is lower than the conditioned air.

When the outside air is in the state a ₁ of the area A, it is humidified when passing through the washer and reaches the saturated state a ₂ even though the absolute humidity of the outside air is higher than that of the conditioned air. Also,
When the outside air is in a state c ₁ state b ₁ and region C in the region B,
Humidification is necessary because the absolute humidity of the outside air is lower than that of the conditioned air. However, when passing through the washer, even if it matches the absolute humidity of the conditioned air, it is further humidified to the saturated states b ₂ and c ₂ . Since the temperatures of the saturated states a ₂ , b ₂ and c ₂ are higher than the dew point temperature T _{0 of the} conditioned air, cooling with a cooler causes condensation of moisture in the air when passing through the cooler. Are dehumidified and cooled to the dew point temperature T ₀ (a ₃ ). Then, when the dew point temperature T ₀ is reached, when it is heated by the heater this time, the absolute humidity is constant and the temperature shifts to the right to reach the set temperature, and the conditioned air in the preset state P ₀ is obtained.

[0005]

However, regardless of the state of the outside air, the washer, cooler, and heater are constantly operated to control the temperature and humidity. Therefore, for example, when the outside air is a _1. However, since the absolute humidity is originally higher than that of the conditioned air, the humidifying operation must be intentionally performed, and the cooling operation must be performed to dehumidify this, and as a result, the temperature drops, so the wasteful operation of further heating operation is performed. There must be.

Therefore, there is a problem in that not only the control operation is wasted, but also the response is slow and the energy and running costs are high. Therefore, it is a technical object of the present invention to reduce unnecessary energy and running costs by eliminating unnecessary operations among humidifying operations, cooling operations, and heating operations according to the state of the outside air, without performing unnecessary control operations. I am trying.

[0007]

In order to solve this problem, the present invention adjusts the outside air to a preset temperature and humidity by a humidifying operation by a humidifier, a cooling operation by a cooler, and a heating operation by a heater. In the operating method of an air conditioner configured to send the conditioned air that has been temperature / humidified to the painting booth, the absolute humidity of the outside air is detected based on the temperature and humidity of the outside air taken in, and the detected outside air When the absolute humidity of is higher than that of the conditioned air, the cooling operation is performed with the humidifier stopped and the surface temperature of the cooler is below the dew point temperature of the conditioned air, and the absolute humidity drops to the absolute humidity of the conditioned air. The temperature of the air is detected by, and when the detected temperature is lower than the set temperature, the heating operation is performed by the heater.

[0008]

According to the present invention, when the absolute humidity of the outside air is higher than that of the conditioned air, first, when the cooling operation is performed with the cooler surface temperature below the dew point temperature of the conditioned air, dew condensation occurs on the surface and dehumidification occurs. When the humidity has dropped to the absolute humidity of the conditioned air, if the temperature is adjusted by heating the heater to a temperature higher than the set temperature and performing a heating operation, conditioned air having a predetermined temperature and humidity can be obtained. When the absolute humidity of the outside air is lower than that of the conditioned air, first, the humidifying operation is performed until it becomes equal to the absolute humidity of the conditioned air. When the enthalpy of the outside air is higher than that of the conditioned air, the cooling operation is performed at the same time, and when the enthalpy of the outside air is lower than that of the conditioned air, the heating operation is performed at the same time to adjust the temperature and the humidity. By doing so, even if one of the humidifying operation, the cooling operation, and the heating operation is omitted depending on the state of the outside air, the conditioned air having a predetermined temperature and humidity can be obtained.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on the embodiments shown in the drawings. FIG. 1 is a psychrometric chart showing the method of the present invention,
FIG. 2 is an explanatory view showing a state change on the air diagram, and FIG. 3 is an air conditioner used in the method of the present invention.

In the figure, reference numeral 1 denotes an air conditioner for controlling the temperature and humidity of the outside air taken in.
Side to air conditioning air outlet 3 side, a washer (humidifier) that humidifies the outside air to a predetermined humidity 4, a cooler (cooler) that cools it to a predetermined temperature 5, a heater (heater that heats it to a predetermined temperature) ) 6 is installed, and a blower fan 7 is arranged at the conditioned air outlet 3.

A humidifying water supply pipe 8 for supplying humidifying water at room temperature is connected to the washer 4, and a humidifying water supply valve 9 for adjusting the flow rate is inserted in the supplying pipe 8.
Further, the cooler 5 is connected with a cooling water supply pipe 10 for supplying cooling water cooled to a dew point temperature of the conditioned air or less, and the surface temperature of the cooler 5 is adjusted by adjusting the flow rate of the cooling water supply pipe 10. A cooling water supply valve 11 is installed.
Further, the heater 6 is provided with a steam supply pipe 12 for supplying steam.
Is connected, and a vapor supply valve 13 for adjusting the flow rate is interposed in the supply pipe 12.

In addition, TH _{1 to} TH ₃ are temperature and humidity sensors, TH ₁ is arranged at the outside airflow inlet 2 so as to detect the state of the outside air, and TH ₂ detects the state of the air passing through the cooler 5. As described above, TH ₃ is arranged on the downstream side of the cooler 5, and TH ₃ is arranged on the conditioned air outlet 3 so that the condition of the conditioned air flowing out from the air conditioner 1 can be monitored.

Reference numeral 14 is a control device for opening and closing the valves 9, 11 and 13 and adjusting the opening thereof. The sensors TH _{1 to} TH ₃ are connected to the input side thereof, and
The valves 9, 11, and 13 are connected to the output side, and the data detected by the sensors TH _{1 to} TH ₃ are arithmetically processed according to a preset program to determine the valve opening. .

Next, the method of the present invention will be described. Figure 1
Is a psychrometric chart with temperature on the horizontal axis and absolute humidity on the vertical axis. The state of the conditioned air is P ₀ (temperature 25 ° C, relative humidity 85%).
RH, absolute humidity 0.017kg / kg), the area A
Indicates that the absolute humidity is higher than that of the conditioned air, area B indicates that the absolute humidity is lower than that of the conditioned air, and enthalpy is higher than that of the conditioned air, and area C indicates that the absolute humidity is lower than that of the conditioned air and that enthalpy is Indicates a state lower than conditioned air.

In this psychrometric chart, the humidifying operation and the heating operation are performed.
Depending on the production and cooling operation, the air condition is as shown in Fig. 2.
Changes to. For example, state P₀Arrow with heating air
If it cools, it moves to the right as indicated by g
The direction differs depending on the temperature of the₀Dew point temperature of air
Degree T ₀Cooling with a higher temperature cooling body is indicated by arrow h
The dew point temperature T changes to the left.₀At lower temperature Tc
When cooled, it changes in the direction indicated by arrow i. Also humidify
If the amount of heat is
If the amount of heat generated is Q (kcal) and the water content is W (kg), the heat-moisture ratio
Direction equal to the direction of the Q / W value shown on the graph (arrow
If it changes to mark j) and there is no heat transfer, Q = 0.
Then, as shown by the arrow f, the enthalpy is constant (heat-moisture ratio =
It changes in the direction of 0).

When the operation of the air conditioner 1 is started, the absolute humidity of the outside air is detected based on the data of the temperature / humidity sensor TH ₁ , and it is determined which of the areas A, B and C the outside air belongs to. At this time, not only the absolute humidity is detected but also the dew point temperature of the outside air may be detected and compared with the dew point temperature of the conditioned air.

Assuming that the outside air is in the state a ₁ of the area A, the absolute humidity is higher than that of the conditioned air, so it is necessary to dehumidify, but it is not necessary to humidify any more. Therefore, the humidifying water supply valve 9 is closed and the humidifying operation is not performed.
The cooling water supply valve 11 is opened to supply the cooling water to the cooler 5 for cooling operation. At this time, the opening degree of the cooling water supply valve 11 is fed back so that the temperature / humidity of the air passing through the cooler 5 is detected by the temperature / humidity sensor TH ₂ and the detected absolute humidity becomes equal to the conditioned air. Selected.

For example, if the surface temperature of the cooler 5 is set to Tc, which is equal to or lower than the dew point T _{0 of the} conditioned air, the moisture in the outside air is condensed on the surface to be dehumidified, and the outside air moves from the state a ₁ to the state a ₄ . When passing through the cooler 5, the absolute humidity becomes equal to the absolute humidity of the conditioned air, and the temperature becomes lower than the set temperature of the conditioned air. Next, when the steam supply valve 13 is opened and steam is supplied to the heater 6 to heat it to the set temperature, the absolute humidity does not change, so the air in state a ₄ shifts to the right in FIG. The temperature and humidity will be adjusted to P ₀ . At this time, the steam supply valve 1
The temperature and humidity of the conditioned air flowing out from the outlet ₃ are detected by the temperature / humidity sensor TH ₃ , and the valve opening degree of 3 is fed back and adjusted so that the temperature becomes equal to that of the conditioned air.

Even when the absolute humidity of the outside air is originally equal to the absolute humidity of the conditioned air, it is not necessary to perform the humidifying operation, and the temperature of the outside air is compared with the set temperature. If the outside air temperature is high, the cooler 5 is used. And the heater 6 heats when the temperature of the outside air is low. Incidentally, in this case, when cooling by the cooler 5, when the surface temperature below the dew point temperature T ₀ of the conditioned air, so will be the formation of the condensate dehumidified, surface temperature and set at dew-point temperature T ₀ higher temperature Cooling water supply valve 1 so that it is below (25 ° C)
It is preferable to adjust the valve opening degree of 1.

Next, assuming that the outside air is in the state b ₁ of the area B, the absolute humidity is lower than that of the conditioned air, so that the humidifying operation is necessary, and the enthalpy is higher than that of the conditioned air.
It is necessary to remove heat. That is, the humidifying operation by the washer 4 and the cooling operation by the cooler 5 are required. At this time, when the amount of water received by the washer 4 is W and the amount of heat removed by the cooler 5 is Q, the air in the state b ₁ changes in the same direction as -Q / W on the heat-moisture ratio graph. Therefore, in order to change the state b _{1 of} the outside air to the state P _{0 of the} conditioned air, hot water obtained by matching the direction determined by the deviation of the temperature and the deviation of the absolute humidity with the direction of the heat-moisture ratio graph. It is sufficient to operate the washer 4 and the cooler 5 in proportion.

Further, assuming that the outside air is in the state c ₁ of the region C, the humidification operation is necessary because the absolute humidity is lower than that of the conditioned air, and the enthalpy is lower than that of the conditioned air. That is, the humidifying operation by the washer 4 and the heating operation by the heater 6 are required. At this time, when the amount of water received by the washer 4 is W and the amount of heat received by the heater 6 is Q, the air in the state c ₁ is as shown in FIG.
On the heat-moisture-ratio graph of, the direction changes in the same direction as Q / W.
Therefore, in order to change the state c _{1 of} the outside air to the state P _{0 of the} conditioned air, the washer 4 and the heater 6 are set with the heat-moisture ratio Uc obtained by matching the direction with the direction of the heat-moisture ratio graph. Just drive.

When the absolute humidity is lower than that of the conditioned air and the enthalpy is equal to that of the conditioned air, the washer 4 is used.
If the humidifying water supply valve 9 is opened to perform humidification until the absolute humidity becomes equal, there is no heat exchange, the enthalpy is constant, the heat-moisture ratio = 0, and the state of the conditioned air reaches P ₀ . , TH ₂ or TH ₃ based on temperature,
Monitor any one of humidity, absolute humidity and dew point temperature,
The opening degree of the humidifying water supply valve 9 of the washer 4 is adjusted so as to match that of the conditioned air.

As described above, no matter which of the areas A, B, and C the outside air belongs to, the humidifying operation is performed more than necessary, or the cooling operation is performed to dehumidify the excessively humidified portion. There is no need for useless operations such as lowering the temperature and performing heating operation, humidify if necessary,
It is designed to heat or cool, and one of the humidifying operation, the heating operation, and the cooling operation can be omitted depending on the state of the outside air, and in some cases, two operations can be omitted, thus eliminating waste of energy. Running costs can be reduced.

[0024]

As described above, according to the present invention, it is determined whether the state of the outside air is higher than the absolute humidity of the conditioned air, and if it is higher, the cooling operation is performed without performing the humidifying operation. Since the conditioned air having a predetermined temperature and humidity can be obtained only by the heating operation, it has an extremely excellent effect that energy and running costs can be reduced without performing unnecessary control operation. Further, if the enthalpy is higher than the conditioned air when the humidity is lower than the absolute humidity of the conditioned air, if the enthalpy is high, the heating operation is not performed and only the humidifying operation and the cooling operation are performed. , If the enthalpy is low, conditioned air of a specified temperature and humidity can be obtained only by the humidifying operation and the heating operation without performing the cooling operation, so either one of the humidifying operation, the cooling operation, and the heating operation can be performed in the outside air. It can be omitted depending on the state, and has an effect of reducing energy and running cost.

[Brief description of drawings]

FIG. 1 is a psychrometric diagram illustrating the method of the present invention.

FIG. 2 is an explanatory diagram showing state changes on the psychrometric chart corresponding to each control operation.

FIG. 3 is a flow sheet showing an air conditioner used in the method of the present invention.

FIG. 4 is a psychrometric chart illustrating a conventional method.

[Explanation of symbols]

1 ... Air conditioner 2 ... Outside air flow inlet 3 ... Air conditioning air outlet 4 ... Washer (humidifier) 5 ... Cooler (cooler) 6 ... Heater (heater) TH ₁ ~ TH ₃ ... temperature and humidity sensor

Front Page Continuation (72) Inventor Yu Uehara 2-4-1, Terauchi Toyonaka, Osaka Prefecture Trinity Industry Co., Ltd.

Claims (2)

[Claims] 1. A humidifying operation using a humidifier, a cooling operation using a cooler, and a heating operation using a heater adjust the temperature and humidity of outside air to a preset temperature and humidity, and send the obtained conditioned air to a coating booth. In the operation method of the air conditioner configured to supply air, the absolute humidity of the outside air is detected based on the temperature and humidity of the outside air taken in, and the humidifier is stopped when the detected absolute humidity of the outside air is higher than that of the conditioned air. In this state, the cooling operation is performed with the surface temperature of the cooler below the dew point temperature of the conditioned air, and when the absolute humidity drops to the absolute humidity of the conditioned air, the temperature of that air is detected and the detected temperature is the set temperature. When the temperature is lower, a heating method is used for heating the air conditioner. 2. The outside air is adjusted in temperature and humidity to a preset temperature and humidity by a humidifying operation by a humidifier, a cooling operation by a cooler, and a heating operation by a heater, and the obtained conditioned air is sent to a coating booth. In the operating method of an air conditioner configured to supply air, a) detect the absolute humidity of the outside air based on the temperature and humidity of the outside air to be taken in, and b) humidify if the detected absolute humidity of the outside air is higher than that of the conditioned air. With the air conditioner stopped, cooler operation is performed with the surface temperature of the cooler below the dew point temperature of the conditioned air, and when the absolute humidity drops to the absolute humidity of the conditioned air, the temperature of that air is detected and detected. When the temperature is lower than the set temperature, heating operation is performed by the heater. C) When the detected absolute humidity of the outside air is lower than that of the conditioned air and the enthalpy of the outside air is higher than that of the conditioned air, a humidifier and cooling We perform humidification operation and cooling operation with container,
The ratio of the amount of water added by the humidifying operation and the amount of heat lost by the cooling operation is set to be equal to the heat-moisture ratio that is determined according to the deviation between the outside air temperature and the set temperature and the deviation between the outside air humidity and the set humidity. When the absolute humidity of the outside air is lower than that of the conditioned air, and the enthalpy of the outside air is lower than that of the conditioned air, the humidifier and the heater perform the humidifying operation and the heating operation.
It is characterized in that the ratio of the amount of water added by the humidifying operation and the amount of heat given by the heating operation is set to be equal to the heat-moisture ratio determined according to the deviation between the outside air temperature and the set temperature and the deviation between the outside air humidity and the set humidity. How to operate the air conditioner.