JPS63176950A - Dehumidifying operation control device for air conditioner - Google Patents

Abstract

PURPOSE:To allow a dehumidifying operation to fully be performed by forcibly stopping the room fan for a predetermined time interval to discharge the drain water while the dehumidifying operation is used way, and, after another predetermined time interval, resuming the room fan operation similarly to the dehumidifying operation. CONSTITUTION:When a dehumidifying command is given while a cooling operation is under way, the air blowing rate of a room fan 5a is reduced by a control means 8a to start a dehumidifying operation. If the difference between the intake air temperature detected by an intake air temperature detecting means TH1 and the set temperature for the room becomes lower than the reference value, the room fan 5a is forcibly stopped so as to prevent drain water from evaporating again. After a predetermined time interval is past from the stoppage of the room fan 5a, the room fan 5a is started by a fan forcibly operating means 10 at a low air blowing rate similarly to the dehumidifying operation, and so, the temperature difference is quickly recovered to a value above the reference, allowing the dehumidifying operation to be resumed.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a dehumidification operation control device for controlling the dehumidification operation of an air conditioner. Concerning the improvement of things installed in vessels.

(Prior art) Conventionally, the dehumidifying operation side of an air conditioner has been used. ! For example, as proposed in Japanese Unexamined Patent Publication No. 61-216233, an air conditioner equipped with a variable volume indoor fan and a suction air temperature detection means is used to dehumidify air during cooling operation of the air conditioner. When an operation command is issued, the air volume of the indoor fan is reduced to perform dehumidification operation, and when the deviation between the intake air temperature and the set temperature reaches a certain value or less, the indoor fan is forcibly stopped and the intake air is When the deviation between the temperature and the set temperature recovers to a predetermined value or higher, the indoor fan is set to low J again! A device is known that operates at lff1 to perform dehumidifying operation.

(Problem to be solved by the invention) By using the above-mentioned conventional method, when the deviation between the intake air temperature and the set temperature is below a certain value during the dehumidifying operation of the air conditioner, the indoor fan is forced to operate. By stopping the
Re-evaporation of drain water from the indoor heat exchanger can be prevented.

By the way, some air conditioners, such as ceiling-mounted air conditioners, have a thermistor for detecting the temperature of the intake air installed inside the indoor unit below the indoor heat exchanger. . In this type of device, while the indoor fan is stopped, air cooled by the indoor heat exchanger flows down to the thermistor, and the apparent intake air temperature is detected to be low.

As a result, the recovery of the deviation between the intake air temperature and the set temperature to a predetermined value or higher is delayed, and it takes a considerable amount of time to return to dehumidifying operation in which the campus fan 1 is operated at a low air volume. Therefore, when the conventional dehumidification operation control device described above is applied to an air conditioner having such a structure, there may be cases where sufficient dehumidification performance cannot be achieved.

The present invention has been made in view of the above, and its purpose is to prevent the indoor fan from stopping after the deviation between the intake air temperature and the set temperature falls below a certain value during the dehumidifying operation of the air conditioner. By taking measures to return to an appropriate dehumidifying operation without controlling the indoor fan using the signal from the suction air temperature detection means, it is possible to prevent the thermistor from being affected by cold air from the indoor heat exchanger in an air conditioner. The purpose of the present invention is to prevent delays in returning to dehumidifying operation due to erroneous detection by the suction air temperature detecting means, and to fully demonstrate dehumidifying operational performance.

(Means for solving the problem) In order to achieve the above object, the solution of the present invention is to forcibly turn on the indoor fan after a sufficient time has elapsed for drain water to be discharged when the indoor fan is stopped during dehumidification operation. The purpose is to make the driver drive the vehicle. Specifically, as shown in FIG.
(1), an outdoor heat exchanger (3), and a reduced pressure I structure (4),
It is equipped with a refrigerant circulation circuit (7) formed by sequentially connecting an indoor heat exchanger (5) having a variable ffl amount type seedling fan (5a), and an indoor heat exchanger (5) connected to the indoor heat exchanger (12). ) is a suction air temperature detection means (TH1) that detects the suction air temperature of
) is installed.

When dehumidifying operation is commanded during cooling operation, the air volume of the indoor fan (5a) is controlled to a small value to perform dehumidifying operation, and the intake air mti( When the deviation (Ta-Ts) between Ta) and the set temperature (Ts) is below the reference value, the operation of the indoor fan (5a) is stopped for a predetermined period of time! !
A control means (8a) for controlling +lJ is provided.

Furthermore, the indoor fan (
A fan forced operation means (20) is provided for controlling the indoor fan (5-a) to forcibly reduce the air volume and operate the indoor fan (5-a) when a predetermined period of time has elapsed after the indoor fan (5-a) has stopped.

(Function) With the above configuration, in the present invention, when a dehumidifying operation command is issued during cooling operation of the air conditioner, the control means (8a) controls the air volume of the indoor fan (5a) to a small value to perform the dehumidifying operation. The intake air temperature (Ta) detected by the intake air temperature detection means (THI) and the indoor set temperature (Ts)
When the deviation (■a-Ts) from the reference value becomes less than the reference value, the indoor fan (5a) is forced to stop, and re-evaporation of drain water is prevented. Then, when a predetermined period of time has elapsed after the indoor fan (5a) stopped, the fan forced operation means (10)
As a result, the indoor fan (5a) is operated with a reduced air volume in the same way as during dehumidification operation, so the value of the deviation (Ta-Ts) quickly recovers to the reference value or higher, and dehumidification operation can be resumed. .

Therefore, due to the influence of cold air from the indoor heat exchanger (5), the return to dehumidifying operation is delayed due to false detection in which the suction air temperature (Ta>) is detected to be lower than the indoor air temperature by the suction air temperature detection means (TH1). This will be prevented as much as possible.

(Example) Hereinafter, an example of the present invention will be described based on the drawings from FIG. 2 onwards.

FIG. 2 shows an embodiment in which the present invention is applied to a ceiling-embedded air conditioner. In Fig. 2, (A) is an outdoor unit;
(B) is an indoor unit, and the above outdoor unit (A
＞ includes a compressor (1), a four-way selector valve (2) that switches as shown in the solid line in the figure during cooling operation and as shown in the broken line in the figure during heating operation, a condenser during cooling operation, and an evaporator during heating operation. On the other hand, the indoor unit (B) has an electric expansion valve (4) as an expansion mechanism that expands the refrigerant, and an evaporator during cooling operation. The main equipment includes an indoor heat exchanger (5) that serves as a condenser during heating operation, and an indoor fan (5a) whose rotation speed is variably adjusted to change the air volume. (5) are sequentially connected to each other by refrigerant pipes (6) so that refrigerant can flow therethrough, forming a refrigerant circulation circuit (7).

As shown in FIG. 3, the indoor unit (B) is installed in a ceiling-embedded structure.

In other words, the indoor unit (8) includes the indoor heat exchanger (5) inside a casing (10) embedded in the ceiling, and a sirocco-type indoor fan (with an air outlet facing the indoor heat exchanger (5)). 5a), and the indoor fan (5a)
), the indoor air sucked in through the suction air passage (11) from the air suction port (11a) provided near the center of the casing (10) is heat-exchanged by the indoor heat exchanger (5), and then the casing ( The air is blown into the room from the air outlet (12) provided on the lower left side of the casing (10) through a duct (not shown) that opens downstream of the indoor heat exchanger (5) and divides the flow. Conditioned air is blown into the room from an air outlet (12) on the lower right side of the air conditioner. In the suction air passageway (11), a thermistor (TH1) as suction air temperature detection means for detecting the suction air temperature is attached below the indoor heat exchanger (5).

Furthermore, Fig. 3 shows the internal circuit configuration of the indoor control unit (8) that controls the operation of the indoor unit (B) and the main wiring of each device connected to the unit (B).
MF) is a fan motor of the indoor fan (5a),
Each relay receives single-phase AC power and connects one terminal (RY+) to (R
Y3) allows the wind monitor to be switched to three stages: strong wind, weak wind, and breeze. A pulse motor (EV) for adjusting the opening of the electric expansion valve (4) is connected to the terminal CN of the printed circuit board of the outdoor control unit (8), and a thermistor (T111) and a remote control switch (RC8) are connected to the terminal CN of the printed circuit board of the outdoor control unit (8). ) is connected so that signals can be input, and the indoor control unit (8) is connected to the indoor fan (5a
) An indoor control device (8a) is built in as a control means for controlling the air volume to a small value to perform a dehumidifying operation.

In FIG. 2, during cooling operation of the air conditioner,
The gas refrigerant compressed by the compressor (1) is condensed and liquefied in the outdoor heat exchanger (3) (condenser), then expanded by the electric expansion valve (4) and transferred to the indoor heat exchanger (5). (evaporator) and returns to the compressor (1) in a gaseous state. At that time, in the indoor unit (B), the indoor control unit (
The indoor control device (8a) of 8) controls the thermistor (
Suction air temperature Ta detected at TH1) and set temperature TS
The opening degree of the electric expansion valve (4) is controlled according to the indoor load expressed as the deviation from the
8affi of a) is set to adjust the capacity of the indoor heat exchanger (5).

The electric expansion valve (
4) The opening degree control and the air pressure control of the indoor fan (5a) will be explained based on the flowchart of Fig. 5. In step S1, the intake air temperature Ta detected by the thermistor (TH1) and the set temperature TS are Determine whether the sampling time has elapsed or not, and if it becomes YES that the sampling time has elapsed,
In step S2, according to the suction air temperature Ta, the maximum permissible opening A l1ax of the electric expansion valve (4), which is the maximum value within the permissible range that does not result in wet operation, is calculated as a function of the suction air temperature Ta, and at the same time, the maximum The minimum allowable opening A, which is the lower limit of the allowable range, is set to have a certain ratio to the allowable opening AmaX.
Calculate ll+n.

Next, in step S3, the remote control switch (
It is determined whether or not a dehumidifying operation command signal from RC8) has been input, and if NO, the process proceeds to step S4.
Perform normal controlled wholesale operation. That is, the indoor fan (5a)
The air volume is as set, and the opening degree A of the electric expansion valve (4) is adjusted to the suction air temperature Ta and set temperature TS shown in the graph of Fig. 6.
Based on the relationship between the deviation (Ta-Ts) and the opening degree A, the formula %
The formula %( is controlled so that
= A IaX, and when A≦A1n, A = A
).

On the other hand, when a dehumidification operation command is issued from the remote control switch (RC8) and the determination in step $3 becomes YES, the deviation (Ta-Ts) is set to the first reference value (4°C) and the second reference value (4°C) in step S5. 0°C), and it is determined whether the deviation (Ta-TS) is in a range of 4°C or higher, a range from 0°C to 4°C, or a range of 0°C or lower.

If the determination is (Ta-Ts)≧4°C, it is determined that the indoor air temperature is too high to perform dehumidification operation, and the process proceeds to step S6, where the guide fan (5a) is operated according to the set value. A normal thermo-operation similar to the above-mentioned normal ffi+1wJ operation in which the opening degree A of the expansion valve (4) is controlled to the above-mentioned calculated value is performed to quickly reduce the indoor air temperature, and step S
After normal thermo-operation is performed until yr(Ta-TS)≦2°C, the process returns to step S1.

Then, the determination in step S5 above is 0°C≦(Ta−T
s) When the temperature is ≦4°C, it is determined that the temperature is within the appropriate temperature range for dehumidifying operation, and in step S8, the indoor fan (5a) is set to the breeze fL, LJ side, and the opening degree A of the electric expansion valve (4) is set to Amax.
Dehumidification operation is performed by controlling the

On the other hand, during the dehumidification operation, the indoor air temperature decreases and the step S
When the determination in step 5 becomes (Ta-Ts) 60° C., it is determined that it is necessary to prevent re-evaporation of the drain from the indoor heat exchanger (5), and the process shifts to the thermo-stop operation from step 89 onwards. First, in step S9, the indoor fan (5a) is forcibly stopped, and the opening degree A of the electric expansion valve (4) is set to rOJ. Then, in step S+a, the control in step S8 is
Repeat this for 3 minutes, and after 3 minutes have passed, proceed to step S o, switch the indoor fan (5a) again to the breeze rLLJ side, control the opening degree A as "0", and use Stellar Play (Ta-
Perform thermostatic stop control until Ts)≧2℃, (Ts)
a-TS)≧2°C (YES), the process returns to the dehumidifying operation described above.

Therefore, in the above flow, steps S1 to SL2
Therefore, when a predetermined period of time has elapsed since the indoor fan (5a) stopped when the air conditioner is in a cooling operation and is in a dehumidifying/dehumidifying operation with a thermostatic stop operation, the WiA of the indoor fan (5a) is
A fan forced operation means (20) is configured to control the fan to operate at a reduced amount.

Therefore, in the above embodiment, when a dehumidification operation command is issued from the remote control switch (RC8) during cooling operation of the air conditioner, the dehumidification operation is started by the control means (8a) upon receiving the signal from the thermistor (TH1). It will be done. That is, based on the change in the value of the deviation (Ta - TS) between the intake air temperature Ta and the set temperature Ts, as shown in Fig. 6, in the range of 0°C < Ta - TS < 4°C, the indoor fan (5
A dehumidifying operation with low power consumption and high dehumidifying efficiency is performed by setting the Jll amount in a) to the breeze rLLJ side and controlling the opening degree A of the electric expansion valve (4) to the maximum allowable opening degree A11aX,
When Ta-Ts≧4°C, the indoor fan (5a) is operated as set and the opening degree A of the electric expansion valve (4) is controlled to the calculated value, which shifts to normal thermo control, so the guiding air temperature quickly increases. It converges to the set value TS and maintains a good air-conditioned feeling. Then, by performing normal thermo control, Ta-Ts≦2
When the temperature reaches ℃, the dehumidifying operation is resumed, so the dehumidifying efficiency does not decrease. Furthermore, when Ta-Ts≦0° C., the indoor fan (5a) is forced to stop in a thermo-stop operation, so that re-evaporation of drain water accumulated in the drain during the cooling operation is prevented. Moreover, when the suction air temperature Ta rises by performing the thermo-stop operation and becomes Ta-Ts≧2° C., most of the drain water is discharged and the dehumidification operation returns again to dehumidify the indoor air.

At that time, if the thermistor (THI) is installed at the bottom of the indoor heat exchanger (5), such as a ceiling-embedded air conditioner, the indoor fan (5a) will stop and the indoor heat will increase. The cooled air around the exchanger (5) naturally flows down to the air suction passage (11), and the thermistor (TH1) detects the value of the suction air temperature Ta lower than the indoor air temperature, and the thermostat stops. Although a situation may arise in which the return from operation to dehumidification operation is delayed, in the above embodiment, when the indoor fan (5a) is stopped and a predetermined time (3 minutes) has elapsed, as shown in FIG. Forced operation means (2
Since the indoor fan (5a) is controlled to the breeze rLLJ side and operated by To quickly return to a state where air temperature is accurately displayed. Therefore, the a difference (Ta-Ts) quickly recovers to the reference value or higher, and dehumidification operation can be performed again.
Delays in returning to dehumidifying operation will be prevented as much as possible. Note that the indoor fan (5a
) is forcibly stopped for 3 minutes, almost all of the drain from the indoor heat exchanger (5) is exhausted, so re-evaporation of the drain does not occur.

The present invention is applicable not only to the ceiling-embedded air conditioner of the above embodiment, but also to a ceiling-suspended air conditioner W device or a temperature sensor such as a thermistor (TH1) placed at the bottom of the indoor unit (B). This can be applied to other air conditioners having the above configuration.

In addition, the above embodiment is an example in which the present invention is applied to an air conditioner in which one indoor unit (B) is arranged for one outdoor unit (A), but one outdoor unit (
It goes without saying that A) can also be applied to a multi-type air conditioner in which a large number of indoor units are arranged.

(Effects of the Invention) As explained above, according to the present invention, in an air conditioner having a suction air temperature detection means, an indoor fan is forcibly stopped only for a predetermined period of time in order to discharge drain water during dehumidification operation. After a predetermined period of time has elapsed, the indoor fan is operated in the same manner as during dehumidification operation, so that the suction air temperature detection means may erroneously detect the suction air temperature due to the flow of cold air from the indoor heat exchanger, causing dehumidification operation to start. Delays in recovery can be prevented as much as possible, and therefore dehumidification performance can be fully demonstrated.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of the present invention. Fig. 2 and subsequent figures show embodiments of the present invention, Fig. 2 is a refrigerant system diagram thereof, Fig. 3 is a vertical cross-sectional view showing a schematic configuration of a ceiling-embedded indoor unit,
Fig. 4 is an electric circuit diagram of the indoor control unit, Fig. 5 is a flowchart showing the control of the indoor control device, Fig. 6 is a switching characteristic diagram of normal thermo-operation, dehumidification operation, and thermo-stop operation, and Fig. 7 is thermo-stop. FIG. 4 is an operation mode diagram of the indoor fan during operation. (1)... Compressor, (3)... Indoor heat exchanger, (4
)...Electric expansion valve (expansion mechanism), (5)...Indoor heat exchanger, (5a) Indoor fan, (7)...Refrigerant circulation circuit, (8a)...Indoor control bag @ (control means), (T
H1)...Thermistor (suction air temperature detection means), (
20)...Fan forced operation means. Shihide 7th figure 6th figure (Ta -Ts)

Claims (1)

[Claims] (1) A compressor (1), an outdoor heat exchanger (3), a pressure reduction mechanism (4), and an indoor heat exchanger (5) having a variable air volume indoor fan (5a) are connected in sequence. Refrigerant circulation circuit (
7), the indoor heat exchanger (12) and the indoor heat exchanger (
5) Suction air temperature detection means (
In the air conditioner equipped with TH1), when dehumidifying operation is commanded during cooling operation, the air volume of the indoor fan (5a) is controlled to a small value to perform dehumidifying operation, and the above-mentioned intake air temperature detection means (TH1) control means for controlling the operation of the indoor fan (5a) to be stopped for a predetermined period of time when the deviation (Ta-Ts) between the intake air temperature (Ta) and the set temperature (Ts) detected by the above is below a reference value; (8a)
and when a predetermined period of time has elapsed since the indoor fan (5a) was stopped under the control of the control means (8a),
A dehumidification operation control device for an air conditioner, comprising a fan forced operation means (20) that forcibly controls an indoor fan (5a) to operate with a reduced air volume.