JP2001289494A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of a conventional float switch detecting dehumidification water mechanically that deposit or dust may adhere to the float switch which is thereby locked and dehumidification water can not be detected. SOLUTION: Since abnormality in the water level of dehumidification water can be detected surely without being influenced by deposit or dust when presence of dehumidification water is detected by sensing the temperature thereof through a temperature sensor, operation of an air conditioner can be stopped before the dehumidification water flows over a drain pan and an abnormality can be indicated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a control system for an air conditioner.

[0002]

2. Description of the Related Art In a conventional system, a float switch is used for detecting dehumidified water as described in, for example, Japanese Patent Application Laid-Open No. Hei 6-137586. Hereinafter, such an operation will be described with reference to FIGS. FIG. 6 is a schematic diagram of an indoor unit structure, and FIG. 5 is a block diagram of a conventional air conditioner. A refrigeration cycle mainly connecting the indoor heat exchanger 1, the compressor 3a, the outdoor heat exchanger 4, and the expansion valve 6, the indoor control circuit 9 and the outdoor control circuit 11 for controlling the indoor blower 2 and the outdoor blower 5, respectively. It consists of. When the air conditioner performs the cooling operation, the indoor heat exchanger 1 in the indoor unit 13 cools down and the condensed water falls on the dew tray 7. In a normal state, the dehumidified water flows out from the drain port of the dew tray 7 to the outside and is drained. However, when dust or the like is clogged in the drain port, the dehumidified water is not drained and accumulates in the dew receiving tray 7, and eventually overflows and wets the room.

When the drain port is clogged and the level of the dehumidified water in the dew receiving tray 7 rises to a certain level, this is detected by the float switch 8 and the operation of the air conditioner is stopped. The operation of the float switch 8 is as follows. In a normal state, that is, a state in which the dehumidifying water is normally drained, the float 18 is at the position shown in FIG. The float switch 8 has a contact 17 disposed in a waterproof cylindrical container. A ring-shaped float 18 is arranged outside the float switch 8, and a magnet 16 is embedded inside the float 18, and the magnetic force closes a contact 17 in the float switch 8.

For example, as shown in FIG. 8, when the drain port of the dew tray 7 is clogged with dirt or the like and rises to a position where the level of dehumidified water is,
As the water level rises, the float 18 and the magnet 16 rise.
Then, since the magnet 16 moves away from the contact point 17, the magnetic force is weakened. As a result, the contact point 17 returns to its original position by spring force and opens. The opening of the contact 17 is input as an electric signal to the indoor microcomputer 10 in the indoor control circuit 9, and the indoor microcomputer 10 detects an abnormality in the level of the dehumidified water, and the compressor motor 3b and the compressor of the air conditioner. The operation of 3a is stopped, and the display lamp 15 for informing that the drainage of the dehumidifying water is abnormal is blinked.

[0005]

In the conventional method, the level of the dehumidifying water is mechanically detected. Therefore, for example, when water scale or dust adheres to the float 18, the float 18 does not move and an abnormality is detected. There was something I couldn't do.

[0006] An object of the present invention is to provide a method capable of reliably detecting an abnormality in drainage of dehumidified water without being affected by scale or dust.

[0007]

The presence or absence of dehumidification water is detected by using a temperature sensor that senses the temperature of dehumidification water without relying on mechanical operation such as a float switch.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. FIG. 2 is a schematic diagram of the indoor unit structure. FIG. 1 is a block diagram of the present invention. Although the configuration is almost the same as that of the conventional example, the temperature sensor 19 connected to the indoor microcomputer 10 is different. As the temperature sensor, for example, a thermistor 19 is used. In a normal state, that is, a state in which the dehumidified water is normally drained, the dehumidified water does not accumulate in the dew receiving tray 7 as shown in FIG. 3, so that the temperature of the thermistor 19 is the ambient air temperature, that is, room temperature. The resistance value of the thermistor 19 is converted into a voltage and input to the indoor microcomputer 10 as a voltage signal.

Next, as shown in FIG.
If the drain port is clogged and the dehumidifying water cannot be drained,
The water level rises to a position where the dehumidified water pools and the thermistor 19 sinks. The temperature of the dehumidifying water is always lower than the ambient air temperature, that is, room temperature, and is usually about 4 to 10C. Thermistor 19
The temperature suddenly drops when it is immersed in dehumidified water, the resistance value changes, and the voltage input to the indoor microcomputer 10 also changes. The indoor microcomputer 10 senses this rapid change in temperature, recognizes that the drainage is abnormal, stops the compressor 3a and the compressor motor 3b, and blinks the display lamp 15 to indicate that the drainage is abnormal.

Since the temperature can be detected when the thermistor 19 comes into contact with the dehumidifying water, it is possible to detect the drainage abnormality of the dehumidifying water without any influence even if, for example, scale or dust adheres to the thermistor.

Further, self-heating is caused by flowing a certain current through the thermistor 19. By doing so, the temperature of the thermistor 19 can be kept several degrees higher than the room temperature, so that the temperature change of the thermistor 19 when submerged in the dehumidified water can be made large, and the level of the dehumidified water can be detected more reliably. . This is particularly effective at low room temperatures.

[0012]

According to the present invention, an abnormality in the level of the dehumidified water can be detected without being affected by water scale or dust, so that the operation of the air conditioner is stopped before the dehumidified water overflows from the dew tray. Can display.

[Brief description of the drawings]

FIG. 1 is a block diagram of an air conditioner of the present invention.

FIG. 2 is a diagram showing a structure of an indoor unit according to the present invention.

FIG. 3 is a diagram showing a normal state of the thermistor according to the present invention.

FIG. 4 is a diagram showing a thermistor state at the time of abnormality according to the present invention.

FIG. 5 is a block diagram of a conventional air conditioner.

FIG. 6 is a diagram showing the structure of a conventional indoor unit.

FIG. 7 is a diagram showing a float switch state in a normal state.

FIG. 8 is a diagram showing a state of a float switch at the time of abnormality.

[Explanation of symbols]

1: indoor heat exchanger, 2: indoor blower, 3a: compressor, 3
b: motor for compressor, 4: outdoor heat exchanger, 5: outdoor blower, 6: expansion valve, 7: dew tray, 8, 19: thermistor, 9: indoor control circuit, 10: indoor microcomputer, 11: outdoor control Circuit, 12: outdoor microcomputer, 13: indoor unit, 14
... outdoor unit, 15 ... indoor indicator lamp, 16 ... magnet, 17 ...
Contact point, 18 ... floating.

Claims (1)

[Claims] 1. A method for detecting dehumidification water during cooling in an air conditioner including a refrigeration cycle including a compressor, a condenser, an evaporator, an expansion valve, and the like, and a blower, a control circuit, and the like. An air conditioner characterized by using a temperature sensor.