JPH0677665B2 - Electronic dehumidifier - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electronic dehumidifier, and more particularly to obtaining a good dehumidifying effect from high humidity to low humidity using an electronic cooling element including a thermoelectric element. The present invention relates to a suitable electronic dehumidifier.

[Conventional technology]

An electronic dehumidifier using a conventional electronic cooling element is disclosed in JP-A-54-
As described in JP-A-112549 and JP-A-54-113951, the cooling surface of the electronic cooling element cools the air, and the cooled air is heated by the radiation surface of the electronic cooling element. In this case, if the temperature of the cooling surface is equal to or lower than the dew point temperature of the air to be blown, the water vapor in the air is condensed on the cooling surface to obtain the dehumidifying effect.

However, the above-mentioned conventional technique has the same air volume on the cooler side and the radiator side, and does not have means for controlling the air volume on the cooler side, and when the humidity becomes low, the temperature of the cooler dew point. As described above, there is a problem that dehumidification cannot be performed.

[Problems to be solved by the invention]

The conventional electronic dehumidifier has a problem that dehumidification cannot be performed when the humidity is low because the air volumes on the cooler side and the radiator side are the same. Also, as the characteristics of the electronic cooling element,
Since the coefficient of performance (cooling capacity / input) becomes smaller as the temperature difference between the cooling side and the radiating side becomes larger, the cooler temperature should be lowered in advance to reduce the humidity when the humidity is low. When the dehumidification is enabled, there arises a problem that the coefficient of performance becomes small at normal humidity when the operating time is long.

An object of the present invention is to provide an electronic dehumidifier capable of performing dehumidifying operation even at low humidity and capable of performing efficient dehumidifying operation even at normal humidity or higher.

[Means for solving problems]

The above-mentioned object is an electronic dehumidifier including an electronic cooling element including a thermoelectric element pair, a cooler including cooling fins, a radiator including heat radiation fins, and an air blower for blowing air to the cooler and the radiator. A humidity sensor mounted on the surface near the upstream end of the cooler and whether or not dew condensation has occurred is determined based on a signal from the humidity sensor, and the amount of air blown from the air blower to the cooler side is cooled. And a control means for controlling the surface temperature of the container to keep it at the dew point temperature.

[Action]

When the electronic cooling element is energized, one becomes cold and the other becomes hot. Therefore, a cooler having cooling fins on the low temperature side and a radiator having heat radiating fins on the high temperature side are provided.
When air is blown to each, the air flowing through the cooler is cooled. Here, if the temperature of the cooler surface is equal to or lower than the dew point temperature, water vapor in the air is condensed on the cooler surface to be removed as water, so that the air is dehumidified while passing through the cooler.

However, in order to perform dehumidification even in low humidity where the dew point temperature is low, it is necessary to further lower the cooler surface temperature and condense steam on the cooler surface.

Therefore, we installed a humidity sensor on the cooler surface and made it possible to reduce the air volume on the cooler side until the humidity sensor detects condensation of water vapor on the cooler surface, which reduces the cooler temperature. As a result, the dehumidification operation becomes possible, and when the humidity is higher than normal, the air flow rate on the cooler side is increased, so the temperature difference with the radiator side becomes small. You can

〔Example〕

The present invention will be described in detail below with reference to the embodiments shown in FIGS.

FIG. 1 is a longitudinal sectional view showing an embodiment of the electronic dehumidifier of the present invention. In FIG. 1, 1 is an electronic cooling element composed of a thermoelectric element pair, 2 is a cooler attached to the cooling side of the electronic cooling element 1, 3 is a cooling fin attached to the cooler 2, and 4 is heat radiation of the electronic cooling element 1. Radiator mounted on the side 5 is radiator 4
Radiating fins attached to the cooler 2 and cooler 2 and radiator 4
The fins of the air blower 20 that blows air to the device, 7 is a water tank that stores the water condensed in the cooler 2, 8 is a filter that removes dust and dirt from the air that is blown to the cooler 2 and the radiator 4, and 9 is the cooler 2 A drain pan 10 that collects condensed water falling from the tank and guides it to the water tank 7 is a housing. Although not shown, a controller for controlling the rotation speed of the fan motor that drives the fan 6 is provided.

By the way, in the present invention, the humidity sensor 21 is attached to the surface of the cooler 2 to monitor whether or not condensed water is present on the surface of the cooler 2.

FIG. 2 is an enlarged view showing an embodiment of the electronic cooling element 1 of FIG. In FIG. 2, the same parts as those in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted here. 11 is an N-type semiconductor,
12 is a P-type semiconductor, 13 is an electric insulator, and 14 is an electric conductor. When a direct current is caused to flow through the electronic cooling element 1 configured as described above, a heat flow is generated in the N-type semiconductor 11 in the electron flow direction and in the P-type semiconductor 12 in the hole flow direction. Therefore, the cooler 2 has a low temperature and the radiator 4 has a high temperature.

FIG. 3 is an electric circuit diagram showing an embodiment of the main electric circuit of the electronic dehumidifier of the present invention. In FIG. 3, reference numeral 15 is a switch, 16 is a protective fuse, 17 is a fan motor that drives the fan 6, 18 is a controller that controls the rotation speed of the fan motor 17, and 19 is AC DC that converts AC power to DC power. In the converter, 1 is an electronic cooling element, 21 is a humidity sensor, 22 is a signal converter of the signal from the humidity sensor 21, and these are connected as shown.

FIG. 4 is a structural explanatory view showing an embodiment of the humidity sensor 21 of FIG. The electrode surface 23 is, for example, a ceramic semiconductor 23.
A comb-tooth-shaped conductive pattern including a pair of electrodes 23a and 23b is formed on c. This humidity sensor 21 is the first
As shown in the figure, it is fixed to the windward surface of the cooler 2 by a suitable fixing means.

FIG. 5 is an explanatory diagram of a signal detection method of the humidity sensor 21, and shows a circuit built in the signal converter 22 connected to the electrode surface 23. In FIG. 5, R is the electrodes 23a, 23b on the electrode surface 23.
The electric resistance between the two is shown, and a voltage divided by the resistance value of the electric resistance R and the resistance value of the fixed resistance R _O is generated at point (a) in the figure. The voltage dividing point (a) is connected to the amplifier circuit A, and the output signal of the amplifier circuit A is connected to the control circuit of the controller 18 of the fan motor 17.

Next, the operation of the electronic dehumidifier configured as described above will be described. When switch 15 is closed, controller 18
The fan 6 is driven by the fan motor 17 via
The air sucked into the housing 10 by the fan 6 passes through the filter 8 after removing dust, dust, and the like while exchanging heat with the cooler 2 and the radiator 4, and passes through the fan 6 to the outside of the housing 10. To be leaked. At this time, since a direct current is supplied to the electronic cooling element 1, the cooler 2 has a low temperature and the radiator 4 has a high temperature. Therefore, the cooler 2
The air passing through is cooled and its temperature drops. At this time, if the surface temperature of the cooler 2 is equal to or lower than the dew point temperature of air,
Water vapor in the air is condensed on the surface of the cooler 2 to be removed as water, and dehumidification is possible. The condensed water falls on the drain pan 9 due to gravity and is collected in the water tank 7. The dehumidified air exchanges heat with the radiator 4 and mixes with the hot air, and passes through the fan 6 to flow out of the housing 10.

On the other hand, the air flowing into the housing 10 has low humidity,
If the surface temperature of the cooler 2 does not fall below the dew point temperature and air cannot be dehumidified, the humidity sensor provided on the surface of the cooler 2
21 sends a signal to the controller 18 via the signal converter 22 that the water vapor does not condense (relative humidity less than 100%). As a result, the controller 18 controls the rotation speed of the fan motor 17 to be small, reduces the amount of air passing through the cooler 2, and lowers the surface temperature of the cooler 2. And repeat this operation,
The rotation speed of the fan motor 17 is reduced until the temperature of the surface of the cooler 2 becomes lower than the dew point temperature. As a result, the dehumidifying operation can be continued until the humidity is low.

As described above, the humidity sensor 21 is used to control the amount of air blown to the cooler 2 so that the surface temperature of the cooler 2 is always kept at the dew point temperature, and the dehumidifying operation is performed. The surface temperature is increased and the temperature difference with the radiator 4 is reduced to perform an efficient dehumidifying operation. On the other hand, when the humidity is low, the air flow rate on the cooler 2 side is controlled so that the surface temperature of the cooler 2 becomes the dew point temperature. Therefore, the dehumidification operation can be performed up to low humidity. As shown in the embodiment of FIG. 1, if the humidity sensor 21 is provided on the upstream side of the air flowing through the cooler 2, even if a temperature difference occurs between the upstream side and the downstream side of the cooler 2, The upstream side, which has the highest temperature, can be maintained at the dew point temperature, and the temperature on the downstream side is naturally lower than the dew point temperature, so that dehumidification can be reliably performed.

If a substance having a slight thermal resistance is interposed between the humidity sensor 21 and the surface of the cooler 2, the surface temperature of the cooler 2 can be controlled when the humidity sensor 21 is controlled to maintain the dew point temperature. Is certainly below the dew point temperature, and the dehumidification operation can be performed more reliably.

Next, another embodiment of the present invention will be described with reference to FIGS. 6 and 7. FIG. 6 is a longitudinal sectional view corresponding to FIG. 1 showing another embodiment of the present invention, and the same portions as those in FIG. 1 are designated by the same reference numerals. In FIG. 6, a radiant air blower 24 for flowing air only through the radiator 4, a radiant fan 25 of the radiant heat blower 24,
A partition plate 26 that divides the air passages on the radiator 4 side and the cooler 2 side and a drain hose 27 that guides condensed water accumulated in the drain pan 9 to the water tank 7 are provided.

FIG. 7 is an electric circuit diagram corresponding to FIG. 3 in the case of FIG. 6, and the same portions as those in FIG. 3 are denoted by the same reference numerals. 7th
In the figure, 28 is a heat radiation fan motor for driving the heat radiation fan 25, and the other components are the same as those in FIG.

Next, the operation of another embodiment configured as described above will be described. Electronic cooling element 1, blower 20, and radiant blower
When electricity is applied to 24, the air is filtered by the fan 6
The air is blown to the cooler 2 through a part of the above, and is discharged to the outside of the casing 10 through the fan 6. On the other hand, air is blown to the radiator 4 through the other part of the filter 8 by the heat radiation fan 25, and is discharged to the outside of the casing 10 through the heat radiation fan 25. At this time, the cooling side of the electronic cooling element 1 becomes low temperature and the heat radiation side becomes high temperature, and heat exchange with the air passing through the cooler 2 and the heat radiator 4, respectively. Therefore, when the surface temperature of the cooler 2 is equal to or lower than the dew point temperature of the passing air, the water vapor condenses on the surface of the cooler 2 so that it can be dehumidified. However, when the air passing through the cooler 2 has a low humidity and a low dew point temperature, as in the case of the first embodiment described with reference to FIGS. The rotational speed of the fan 6 is reduced until the humidity sensor 21 provided detects condensation, and the amount of air passing through the cooler 2 is controlled. With the above operation, dehumidification operation can be performed down to low humidity, and when the humidity is higher than normal humidity, the air volume on the cooler 2 side is increased and the temperature difference between the heat radiation side and the cooling side of the electronic cooling element 1 is reduced. It enables dehumidifying operation with a high coefficient of performance. Further, when the radiator 4 side and the cooler 2 side are blown by separate blowers as in the present embodiment, even when the cooler 2 side air volume is reduced when the humidity is low, the radiator 4 side air volume remains the same. Since the operation can be performed while keeping it large, the dehumidifying operation can be performed without increasing the temperature of the radiator 4. Therefore, the electronic cooling element 1 at low humidity
There is also an effect that it is possible to reduce a decrease in the product coefficient of.

In the embodiment shown in FIG. 6, the air passing through the cooler 2 and the radiator 4 is discharged in different directions.
The direction of air flow may be changed, and after passing through the cooler 2 and the radiator 4, they may be mixed and discharged.

Moreover, when the electronic dehumidifier according to the present invention is used at a low temperature, the surface temperature of the cooler 2 may be 0 ° C. or lower, and frost may occur. When frost forms on the surface of the cooler 2, its heat resistance lowers the heat exchange performance, lowers the dehumidifying capacity, and at the same time causes freezing in the humidity sensor 21, which causes the humidity sensor 21 to cool.
May shorten the life of the. Therefore, when considering use at low temperature, a temperature sensor such as a thermistor is attached near the humidity sensor 21, particularly on the surface of the cooler 2 on the downstream side, and when the temperature reaches 0 ° C., the temperature sensor is stopped or the electronic cooling element is installed. It is necessary to add a control device that performs a defrosting operation such as changing the polarity of 1.

〔The invention's effect〕

As described above, according to the present invention, the humidity sensor provided on the surface of the electronic cooling element near the upstream end of the cooler detects dew condensation on the cooler surface, and the cooler-side air volume determines the cooler surface temperature. Since it is controlled to keep the dew point temperature, dehumidifying operation is possible even at low humidity, and when the humidity is higher than normal humidity, the temperature difference between the cooler and the radiator is reduced to achieve efficient dehumidifying operation. There is an effect that is possible.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the electronic dehumidifier of the present invention, FIG. 2 is an enlarged view showing an embodiment of the electronic cooling element of FIG. 1, and FIG. 3 is an electronic dehumidifier of the present invention. FIG. 4 is an electric circuit diagram showing an example of the main electric circuit of FIG. 4, FIG. 4 is a structural explanatory view showing an example of the humidity sensor of FIG. 1, and FIG. 5 is a signal detection method of the humidity sensor of FIG. FIG. 6 is an explanatory view showing an embodiment, FIG. 6 is a longitudinal sectional view corresponding to FIG. 1 showing another embodiment of the present invention, and FIG. 7 is an electric circuit diagram corresponding to FIG. 3 in the case of FIG. Is. 1 ... Electronic cooling element, 2 ... cooler, 3 ... cooling fin, 4 ... radiator, 5 ... radiating fin, 6 ... fan, 17 ... fan motor, 18 ... controller, 20 ... Blower, 21 …… Moisture sensor, 22 …… Signal converter.

Claims (1)

[Claims] 1. An electronic dehumidifier comprising an electronic cooling element including a thermoelectric element pair, a cooler having cooling fins, a radiator having heat radiation fins, and a blower for blowing air to the cooler and the radiator. A humidity sensor attached to the surface near the upstream end of the cooler, and determines whether or not dew condensation has occurred based on a signal from the humidity sensor, and determines the amount of air blown from the blower to the cooler side. An electronic dehumidifier, comprising: a control means for controlling the surface temperature of the cooler to maintain the dew point temperature.