JPH04371732A - Device for controlling operation of drainage pump for air conditioner - Google Patents

Abstract

PURPOSE:To reduce a drain noise to be made by a drainage pump for an air conditioner. CONSTITUTION:A drainage pump 4 is provided to discharge drain water in a drain pan 3 disposed underneath a heat exchanger 2. When a compressor is operated during the cooling or dehumidifying operation of an air conditioner, the drainage pump 4 is controlled to stop its operation by an operation controlling means 20 if a water level of drain water in the drain pan 3 is lowered down to the level of a lower limit value and lower, while the drainage pump is allowed to start its operation if a water level of drain water reaches the level of an upper limit value or higher. This method makes it possible to prevent a loud drain noise attributable to the lowering of a water level of drain water from being made and reduce a drain noise.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation control device for a drain pump for discharging drain water from a drain pan of an air conditioner, and more particularly to measures for reducing drainage noise.

0002

[Prior Art] Conventionally, for example, Utility Model Publication No. 63-3305
As disclosed in Japanese Patent No. 9, as shown in FIG. When dehumidifying operation is started (time t10 in the figure), the drain pump is operated after a predetermined time has passed (time t11 in the figure), and after the air conditioner is stopped or the thermostat is turned off (time t10 in the figure). At time t12),
Run the drain pump for a certain period of time and then stop it (
A known technique attempts to continue the smooth operation of the air conditioner by discharging the accumulated drain water from the heat exchanger at time t13) in the drain pan.

0003

[Problems to be Solved by the Invention] However, when the drain pan pump is operated, as in the conventional system described above, when the amount of water held in the drain pan decreases and the water level drops, the draining sound of the drain pump becomes abnormally loud. There was a problem. That is, FIG. 4 shows the change in drainage sound with respect to the water level of drain water, and it can be seen that when the water level reaches the vicinity of the inlet of the drain pump, the drainage sound suddenly becomes higher. This is because air is drawn into the drain pump, but as shown in Figure 4, immediately after the air conditioner starts operating the cooling system, the amount of drain water dripping decreases due to condensation of moisture from the indoor air. Although there are quite a lot of them (at time t10 in the figure)
- t11), as the indoor air dries as cooling progresses, it decreases, and after a certain amount of time has passed after the drain pump starts operating (after time ts in the figure), the drain pump starts suctioning. It is maintained at the lowest possible position Lo. Therefore, while the air conditioner is operating, the high-pitched drainage sound continues, and this drainage sound is transmitted into the room from the heat exchanger, etc. placed facing the room, causing discomfort to the users. Become.

The present invention has been made in view of the above, and its purpose is to maintain the water level in the drain pan at a level higher than the position where the above-mentioned high drainage sound occurs. The purpose is to reduce drainage noise and thereby improve the comfort of air conditioning.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the means taken by the invention of claim 1 are as shown in FIG.
The present invention is directed to an operation control device for a drain pump (4) for discharging drain water in a drain pan (3) located below a heat exchanger (2) of an air conditioner to the outside.

[0006]The water level detection means (Lm) detects the water level of the drain pan (3);
), when the compressor is operating during the cooling or dehumidifying operation of the air conditioner, if the water level of the drain water in the drain pan (3) falls below the lower limit, the drain pump (4) is stopped, and then the drain water is An operation control means (20) is provided for controlling the drain pump (4) to operate when the water level exceeds an upper limit value which is higher than the lower limit value by a certain value.

The means taken by the invention of claim 2 is such that the operation control means (20) in the invention of claim 1 is configured such that the water level of drain water in the drain pan (3) can be sucked after the operation of the air conditioner is stopped. Drain pump (4) until it reaches the lowest position.
).

The means taken by the invention of claim 3 is such that the operation control means (20) in the invention of claim 1 or 2 is controlled by the drain pan ( 3) The drain pump (4) is operated until the water level of the drain water in the drain pump (4) reaches the lowest level at which it can be sucked.

[0009]

[Function] With the above configuration, in the invention of claim 1, when the compressor is operating during cooling or dehumidifying operation of the air conditioner, the operation control means (20) controls the water level detection means (Lm).
When the water level of drain water in the drain pan (3) detected by the drain pump (4) is stopped when it falls below the lower limit value, the water level of the drain water will not drop to a level that would cause high drainage noise. . Moreover, after that, when the water level of the drain water rises and exceeds the upper limit value, the drain pump (4) is operated, so that the drain water does not overflow from the drain pan (3), and smooth operation is maintained. Therefore, drainage noise is reduced and the comfort of air conditioning is improved.

[0010] In the invention of claim 2, the operation control means (20
), after the compressor stops, the drain pump (4) remains in operation until the drain water level reaches the lowest level that can be sucked, so the water level in the drain pan (3) is maintained at the lowest level, and the compressor Even if residual water drops drip from the heat exchanger (2) during the stoppage, accidents such as drain water flowing out from the drain pan (3) due to a rise in the water level are prevented.

In the invention of claim 3, the operation control means (20
), after the air conditioner shifts from cooling operation to heating operation or ventilation operation, the residual operation of the drain pump (4) is performed until the water level of the drain water reaches the lowest position where it can be sucked. The same effect as that of the invention can be obtained.

0012

[Embodiments] Hereinafter, embodiments of the present invention will be explained based on FIGS. 1 and 2.

FIG. 1 shows the structure near the drain pan of an air conditioner according to an embodiment of the present invention. A heat exchanger (2) for performing the exchange is provided below the heat exchanger (2), and a water droplet condensed by the heat exchanger during cooling or dehumidification operation of the air conditioner is placed below the heat exchanger (2). A drain pan (3) is provided for storage. A drain pump (4) for discharging drain water is attached to the drain pan (3), and the drain pump (4) connects the casing (11) and the casing (11).
) an impeller (12) housed with a certain gap between the impellers (12)
and a motor (13) that rotationally drives the impeller (12).
and a connecting rod (14) that connects the motor (13) and the impeller (12).

[0014] The casing (1) of the drain pump (4)
1) has a side wall (11a) formed in the shape of an inverted truncated cone;
The lower end of 11a) is opened to serve as an inlet (11b), and a portion of the upper part of the side wall (11a) is formed into a horizontally projecting tubular shape to serve as a discharge pipe (11c). Also,
Although not shown, the impeller (12) is provided with an impeller. The suction port (11b) of the casing (11) is placed at a predetermined position within the drain pan (3) and is normally immersed in drain water. That is, impeller (1
Drain water is sucked up from the suction port (11b) by the rotational drive of 2), and the drain pipe (11c) is connected to the discharge pipe (11c).
5) is discharged to the outside.

Furthermore, the drain pan (3) is equipped with a water level gauge (Lm) as a water level detection means for detecting the water level of drain water.
) is attached, and the signal of the water level gauge (Lm) is connected to the controller (20) of the air conditioner so that it can be input, and the controller (20) controls the drain pump (4).
In other words, the motor (13) is turned on and off.

Next, the details of the operation control of the drain pump (4) by the controller (20) will be explained. Figure 2 shows the relationship between the operation control of the drain pump (4) and the change in water level during that time.
b) shows whether the drain pump (4) is on or off.

When the compressor starts operating (time to in the figure), the water level of the drain water is at the lowest position Lo, but in this state, the drain pump (4) is kept stopped (
(from time to to t1 in the figure). Then, when the water level rises and reaches the upper limit L1 (time t1 in the figure)
), the upper limit signal is output, and the drain pump (4) is operated. After that, when the water level decreases and reaches the lower limit value L2 which is higher than the above-mentioned lowest position Lo (time t2 in the figure)
, stop the operation of the drain pump (4). Then, the above process is repeated and when the thermostat turns off (time t3 in the figure)
), during which time the drain pump (4) should be stopped. After the thermostat is turned on (after time t4 in the figure), the above-mentioned on/off control is repeated, and when the operation of the air conditioner is stopped (time t5 in the figure), the drain water level The remaining operation of the drain pump (4) is performed until the drain pump (4) reaches the lowest suctionable position Lo (until time t6 in the figure). The above control by the controller (20) constitutes the operation control means referred to in the present invention.

Here, the lower limit value L2 of the water level is set at a position higher than the suction port (11b) of the drain pump (4), that is, at a water level near the lower limit of the low drainage noise range shown in FIG.

Therefore, in the above embodiment, when the compressor is operated during the cooling or dehumidifying operation of the air conditioner, the operation control means (20) causes the drain water level in the drain pan (3) to be lower than the lower limit L2. When it comes to drain pump (4
) is stopped, so the water level of the drain water does not drop to a level that would cause high drainage noise. That is, Figure 4
As shown in Figure 2, generally speaking, the draining sound of the drain pump (4) is caused by the drain water level being lower than the suction port (11) of the drain pump (4).
b) When the drain water level is sufficiently higher than the drain pump (4), it is small, but when the drain water level approaches the suction port (11b) of the drain pump (4), not only the drain water but also air is drawn in, so the drainage sound increases and It has a characteristic that after reaching the maximum level at , when the drain water level drops to the suction port (11b) and drain water is no longer sucked, it decreases again. Therefore, the lower limit value L2 above the predetermined position where the drainage sound becomes high
By stopping the operation of the drain pump (4) when this occurs, drainage noise can be reduced.

Further, when the drain water level rises and reaches the upper limit L1, the drain pump (4) is operated, so that the drain water does not overflow from the drain pan (3) and smooth operation is possible. maintained. Therefore, it is possible to improve the comfort of air conditioning by reducing drainage noise.

[0021] After the compressor is stopped, the drain pump (4) is operated until the water level of the drain water reaches the lowest suctionable position Lo.
By performing residual operation, the water level in the drain pan (3) is maintained at the lowest position Lo, so even if residual water drops drip from the heat exchanger (2) while the compressor is stopped, it will not occur due to the rise in water level. Accidents such as drain water flowing out from the drain pan (3) can be effectively prevented.

[0022]Although the example is omitted, the residual operation as in the above example is performed even when the cooling operation is shifted to the heating operation or the ventilation operation, and in this case also, the above implementation is performed. The same effect as in the example can be obtained.

[0023]

As described above, according to the invention of claim 1, an air conditioner can be used as an operation control device for a drain pump that discharges drain water in a drain pan disposed below a heat exchanger of an air conditioner. When operating the compressor during cooling or dehumidification operation of the equipment, the drain pump is stopped when the water level of drain water falls below the lower limit, and then starts operating when the water level rises above the upper limit. It is possible to effectively reduce the drainage sound of the drain pump caused by a drop in the water level, and therefore, it is possible to improve the comfort of air conditioning.

According to the invention of claim 2, in the invention of claim 1, after the operation of the air conditioner is stopped, the drain pump remains in operation until the water level of the drain water reaches the lowest level at which it can be sucked. Therefore, while the air conditioner is stopped,
It is possible to effectively prevent an abnormal rise in the water level in the drain pan due to dripping of residual water droplets from the heat exchanger.

According to the invention of claim 3, in the invention of claim 1 or 2, when transitioning from cooling operation to heating operation or blowing operation, the drain pump is operated until the water level of the drain water reaches the lowest position where it can be sucked. Since the residual operation is performed, it is possible to effectively prevent an abnormal rise in the water level in the drain pan due to dripping of residual water droplets from the heat exchanger during the heating operation of the air conditioner.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the structure of an air conditioner according to an embodiment.

FIG. 2 is a diagram showing the relationship between changes in the level of drain water and on/off of the drain pump in the embodiment.

FIG. 3 is a diagram showing the relationship between changes in the level of drain water and on/off of the drain pump in conventional drain pump operation control.

FIG. 4 is a diagram showing the change characteristics of the drainage sound of the drain pump with respect to the water level of drain water.

[Explanation of symbols]

2 Heat exchanger 3 Drain pan 4 Drain pump 20 Controller (operation control means) Lm Water level meter (water level detection means)

Claims (3)

[Claims] 1. An operation control device for a drain pump (4) for discharging drain water in a drain pan (3) disposed below a heat exchanger (2) of an air conditioner to the outside, the drain pan A water level detection means (Lm) detects the water level of (3), and when the output of the water level detection means (Lm) is received, when the compressor is operated during cooling or dehumidification operation of the air conditioner, the water level in the drain pan (3) is The drain pump (4) is controlled to be stopped when the water level of the drain water becomes below the lower limit value, and then to be operated when the water level of the drain water becomes above the upper limit value which is higher than the lower limit value by a certain value. An operation control device for a drain pump of an air conditioner, comprising an operation control means (20). 2. The operation control device for a drain pump of an air conditioner according to claim 1, wherein the operation control means (20) comprises:
An air conditioner characterized in that after the operation of the air conditioner is stopped, the drain pump (4) is controlled to be operated until the water level of drain water in the drain pan (3) reaches the lowest position where it can be sucked. Drain pump operation control device. 3. The operation control device for a drain pump of an air conditioner according to claim 1 or 2, wherein the operation control means (20
) controls the drain pump (4) to operate until the level of drain water in the drain pan (3) reaches the lowest level at which suction is possible when the air conditioner shifts from cooling operation to heating operation or blowing operation. An operation control device for a drain pump of an air conditioner, characterized in that: