JPH0646368B2 - Condensation prevention method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a dew condensation preventing method for preventing dew condensation of a stored item in a warehouse or the like.

[Conventional technology]

As a method of preventing the occurrence of dew condensation in a warehouse, etc., it is possible to constantly air-condition the inside of the warehouse, but it is enormous running cost to perform constant air conditioning for the occurrence of a connection that does not know when it will occur. Will be needed. Therefore, the temperature and humidity sensor is used to detect the possibility of dew condensation, and only when there is a risk of dew condensation, the dehumidifier is activated to reduce operating costs. In this case, with respect to the timing of operating the dehumidifier, a dew condensation prevention margin temperature difference is manually set in the dew condensation prevention detector, and when the set value is reached, the dehumidifier starts operating. Also, to prevent condensation, warm air that stays near the ceiling provided in the ceiling of the warehouse is blown onto the floor surface to raise the floor surface temperature and agitate the air inside the warehouse to prevent localized condensation. Was.

[Problems to be solved by the invention]

The conventional dew condensation prevention system is configured as described above, and the dew condensation prevention temperature difference is set manually, and the same temperature difference is set during the day as well. The temperature difference had to be set large, and it was not possible to obtain a sufficient effect for surely preventing condensation and reducing operating costs. Regarding the ceiling fan for preventing dew condensation, its capacity was selected only by considering the agitation of indoor air, and the effect of preventing dew condensation was not particularly considered.

The present invention has been made to solve the above problems, and an object of the present invention is to effectively reduce the dew condensation damage and to reduce the operating cost of the dehumidifying equipment at a margin. .

[Means for solving problems]

The dew condensation prevention system according to the present invention includes a sensor that detects the temperature and humidity of the outside air, a sensor that detects the floor temperature, a calculation circuit that obtains a dew point, and a dew condensation prevention margin temperature that automatically switches the set value between daytime and nighttime. A difference setting device is provided, and the operation of the dehumidifier is turned on / off according to each set value.

[Work]

In the dew condensation prevention system according to the present invention, the temperature and humidity are detected by a sensor that detects the temperature and humidity of the outside air and a temperature sensor that is attached to the floor or luggage inside the room, and there is a dew condensation risk based on the air diagram incorporated in the arithmetic circuit. Even if the condition is judged and the dew condensation state is reached, the dew condensation prevention margin temperature difference is set to 0 during the day, for example.
The temperature is automatically set to 2 ° C to 4 ° C at night, and the dehumidifier is turned on / off at each set value.

Example of Invention

FIG. 1 is a block diagram of a dew condensation preventing system showing an embodiment of the present invention. In the figure, (1) is an outside air sensor that detects the temperature and humidity of the outside air, (2) is a temperature sensor attached to the floor of the warehouse or the stored luggage, (10)
Is a dew condensation prevention detector, which incorporates (11) to (18) described below. (11) is an arithmetic circuit composed of a microcomputer, etc.
Judgment of dew condensation risk is made by the air diagram that is stored. (12) is a setting device that sets the dew condensation prevention temperature difference, (13)
Is the dew point temperature and temperature sensor (2) required by the arithmetic circuit (11).
A comparison circuit that compares the difference between the floor temperature due to the outside temperature and the dew condensation prevention margin temperature difference set by the setting device (12). Lower limit comparison circuit for comparing the upper limit value (35 ° C.) and the floor surface temperature measured by the temperature sensor (2).
6) and (17) are AND circuits, (18) is H from AND circuit (17)
It is a remote controller that operates on output.

Next, the operation of the dew condensation prevention system configured as described above will be described. The temperature and humidity signals of the outside air detected by the outside air sensor (1) are input to the arithmetic circuit (11), and the dew point temperature Td is obtained from the air diagram stored in the ROM of the arithmetic circuit (11). The comparison circuit (13) calculates the difference (Tr-Td) between the calculated outside air dew point temperature Td and the floor surface temperature Tr detected by the temperature sensor (2), and is set by the setter (12). Compared with the dew condensation prevention margin temperature difference ΔT, ΔT> (Tr-T
If it is d), an H level signal is output. The lower limit comparison circuit (14) outputs an H level signal when the outside air temperature measured by the outside air sensor (1) is 5 ° C. or higher, and outputs an L level signal when the outside air temperature is 5 ° C. or lower. Furthermore, the upper limit comparison circuit (15)
Outputs an L level signal when the floor surface temperature by the temperature sensor (2) is 35 ° C. or higher, and outputs an H level signal when the floor surface temperature is 35 ° C. or lower. And these outputs are AND circuit (16),
The logical product is taken in (17) and the dew condensation prevention temperature difference (Tr-Td)
Is the set value ΔT or less, the outside air temperature is 5 ° C or more, and the floor surface temperature is 3
Under a condition of 5 ° C. or less, an H level signal is output, the remote controller (18) is operated to output a dew condensation alarm and a dehumidification command, and a dehumidifier (not shown) is operated.

In addition, the dew condensation prevention temperature difference set by the setting device (12) is
The set value can be automatically switched between daytime and nighttime by a clock device (not shown), for example, 0 ° C during the daytime and 3 ° C during the nighttime, and the dehumidifier is operated according to the risk of dew condensation. Therefore, the operating cost of the dehumidifier can be reduced by 90% or more while sufficiently preventing the risk of dew condensation.

Here, the capacity of the dehumidifier is selected by calculating the necessary dehumidification amount by appropriately assuming the dew condensation generation condition based on the ingress outside air temperature and humidity, the load surface temperature in the warehouse, the volume in the warehouse, and the ventilation frequency. When making assumptions about this temperature, make decisions by taking into account the timing of dew condensation and the location conditions of the warehouse.

As a dew condensation prevention system, if warm air that stays near the ceiling is blown toward the floor surface by a ceiling fan and the air is agitated to raise the floor surface temperature, it is extremely effective in preventing dew condensation. As an example of actual measurement, as shown in FIG. 2 (a), the temperature near the floor surface is about 3 minutes after the system is operated for about 10 minutes.
℃ rise, and relative humidity is about 70% as shown in (b).
To about 60%, and stirring air with a ceiling fan is also effective in preventing dew condensation. In this case, the capacity of the ceiling fan sets the wind speed reaching the floor to a range of 0.1 to 0.2 m / sec. In addition, when the wind speed reaching the floor surface is set to 0.1 to 0.2 m / sec or less, the air cannot sufficiently obtain the stirring effect, while when it is set to 0.1 to 0.2 m / sec or more, the ceiling fan becomes an excessive capacity and electric power is consumed. Waste, and dust is wound up due to excessive agitation, and various inconveniences are caused by an increase in wind speed.

〔The invention's effect〕

As described above, according to the present invention, the set value of the dew condensation prevention margin temperature difference is automatically switched between daytime and nighttime, and according to the embodiment, the wind velocity reaching the floor surface by the ceiling fan is about 0.1 to 0.2 m / sec. With this configuration, the dehumidification damage can be effectively prevented, and the operating cost of the dehumidification system can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a block diagram of a dew condensation preventing system showing an embodiment of the present invention, and FIGS. 2 (a) and 2 (b) are diagrams showing a dehumidifying effect by a ceiling fan. In the figure, (1) is an outside air sensor, (2) is a floor temperature sensor,
(10) is a condensation prevention detector, (11) is an arithmetic circuit, (12) is a condensation prevention margin temperature difference setter, (13), (14), (15) are comparators, and (1
6) and (17) are AND circuits, and (18) is a remote controller.

Claims (2)

[Claims] 1. In a dew condensation prevention system in a warehouse or the like, a temperature / humidity sensor for detecting the temperature and humidity of outside air, a temperature sensor attached to an indoor floor or luggage to detect a floor surface temperature, and a calculation for calculating a dew point temperature. It is equipped with a circuit and a dew condensation prevention margin temperature difference setting device that automatically switches the set value between daytime and nighttime.The comparison value between the difference between the floor surface temperature and the dew point temperature and the dew condensation prevention margin temperature, the outside temperature Of the dehumidifier is turned on by the logical product of the lower limit value of
A dew condensation prevention method characterized by being turned off. 2. The dew condensation preventive temperature set value is almost 0 in the daytime.
The dew condensation prevention system according to claim 1, wherein the temperature is automatically switched to about 2 to 4 ° C at night.