JPH0436535A - Method of operating indoor fan of air conditioner - Google Patents

Abstract

PURPOSE:To provide a uniform distribution of an indoor temperature by a method wherein under a low heating operation, an amount of blow air of an indoor fan is varied to get a small amount of blow air and an increased amount of blown air larger than the former one. CONSTITUTION:As a heating load is decreased, a compressor 5 is operated at a low power supply frequency and at the same time the number of revolution of an indoor fan 2 is also decreased to cause a small amount of air blown to be got. After this operation, a room temperature sensed by a sucking temperature sensor 14 is compared with a set temperature set at an operating part 11 by a temperature value comparing means 21. If the room temperature is higher than the set temperature, a control part 20 judges that there is a certain influence of a short-circuit such as a flow P. Then, the control part 20 increases the number of revolution of the indoor fan 2 up to such a value as one where a blown air P1 can reach a part near a central portion in the room. Then, the operation of increasing an amount of blown air is continued for a specified period of time by the clocking of a timer circuit 24.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an indoor fan operating method for an air conditioner that cools and heats a room.

(Prior art) Heat pump type air conditioners have some form of wall hanging. This wall-mounted air conditioner has an indoor heat exchanger 1 and an indoor fan 2 (for example, a motor 2a connected to a cross-flow fan 2b) as shown in FIG. The outdoor unit 3 has a built-in outdoor heat exchanger 4, a closed type compressor 5 (with a motor and compression mechanism built in a sealed case), a pressure reducing device, a four-way valve (none of which are shown), etc. A structure in which the unit 6 is connected with a refrigerant pipe 7 is used. This makes it possible to switch between the cooling cycle and the heating cycle.

In addition, by operating the indoor fan 2, the indoor air is heat exchanged with the indoor heat exchanger 1. Specifically, as shown in FIG. 8, when the indoor fan 2 operates, air from the room 9 is sucked in through the suction port 8 provided at the front of the indoor unit 3, guided to the indoor heat exchanger 1, and then transferred to the indoor heat exchanger 1. Heat is exchanged with a heat exchanger 1, and the indoor air (cold air/warm air) after the heat exchange is blown out from an outlet 10 provided at the lower part of the indoor unit 3.

By the way, in the control structure of such an air conditioner, as shown in FIG. An indoor heat exchange sensor 13 for detecting the temperature of the heat exchanger 1, installed on the suction side of the indoor unit 3 (air path section upstream with respect to the indoor heat exchanger 1) for detecting the indoor temperature. Connect the suction temperature sensor 14. Further, a structure is used in which the compressor 5 is connected to the output side of the control section 12 via an inverter circuit 15, and the motor 2a of the indoor fan 2 is connected via an indoor fan drive circuit 16.

Conventionally, the above-mentioned air conditioners have been controlled in the following manner using such control equipment.

That is, the control unit 12 calculates the deviation (air conditioning load) between the room temperature detected by the suction temperature sensor 14 and the set temperature set by the operation unit 11, and calculates the deviation (air conditioning load) from the power frequency information of the compressor 5 corresponding to the deviation (not shown). , read the power frequency corresponding to the deviation determined above.

Then, the control unit 12 outputs an instruction signal to the inverter circuit 15 to control the operation of the compressor 5 so that the power supply frequency is the same, and air-conditioning/heating operation is performed at a capacity corresponding to the load. At the same time, the control unit 12 controls the rotation speed of the indoor fan 2 according to the temperature of the indoor heat exchanger 1, and sets the air volume so that the blowout temperature does not drop during heating operation. ing.

(Problem to be solved by the invention) However, when the outside air temperature is high and the heating load is small, the heating operation is good depending on the load, that is, the refrigeration cycle is operated with a reduced heating capacity, and the blowing temperature is increased. Therefore, the indoor fan 2 operates at a reduced air flow rate (because the feeling of heating is impaired when the blowing temperature becomes low).

By the way, as shown in FIG. 8, the indoor unit 3 is
Indoor air is sucked in from the suction port 8 on the front of the main body, and is blown out downward from the air outlet 10 at the bottom of the main body via the vertical air direction grille 17.

However, the Suita wind during low-load heating operation is quite small in both air volume and flow velocity. Therefore, when the above-mentioned low-load heating operation starts, the blown air whose temperature is higher than the ambient temperature rises from immediately after the air outlet 10 due to the influence of natural convection, as shown by flow P in FIG. 8, and rises again. There is a problem that a so-called air short circuit occurs in which the indoor air is sucked in from the front suction port 8 and circulated.

If this air short circuit occurs, indoor 9
air distribution becomes uneven.

Moreover, even though the actual average indoor temperature is low, the suction temperature sensor 14 detects a higher short-circuited air temperature as room temperature. False detection is
Even if the true room temperature is below the set temperature, the control unit 12 determines that it is above the set temperature and stops the heating operation or shifts to extremely low capacity operation.
This results in the problem of not being able to maintain the room temperature at the set temperature. Specifically, as shown in FIG. 9, the heating operation repeatedly stops around the set temperature, or continues without the true room temperature reaching the set temperature.

This invention was made with attention to these circumstances,
The purpose is to provide an indoor fan operating method for an air conditioner that can uniformize the indoor temperature distribution and at the same time perform low-load heating operation with accurate room temperature detection.

[Structure of the Invention (Means for Solving the Problems and Their Effects)] In order to achieve the above object, according to the indoor fan operating method for an air conditioner of the present invention, a An indoor fan that sucks indoor air through its mouth, guides it to the indoor heat exchanger, and blows it out from the outlet of the main body is operated while changing the airflow volume to a small airflow volume, a small airflow volume, and an increased airflow volume during low-load heating operation. .

Then, this change from a small air volume to an increase in air volume causes a short circuit, causing the hot air that had been stagnant around the air conditioner itself to blow out into the center of the room.

This keeps the indoor temperature distribution uniform. At the same time, since short-circuited high-temperature air is not sucked in from the suction port, the room temperature can be detected accurately, and the room temperature can be controlled to the set temperature even during low-load heating operation.

(Example) The present invention will be described below based on an example shown in FIGS. 1 to 4. In addition, in this example, the above “
Since the structure of the air conditioner described in the ``Prior Art'' section is the same, the explanation of the same structure will be omitted by using Figures 7 and 8, and in this section, the main control will be explained. I would like to explain the relevant points.

That is, 20 is a control section. The control unit 20 includes a temperature value comparison unit 21 for comparing, for example, the room temperature detected by the suction temperature sensor 14 and the set temperature set by the operation unit 11.
, a compressor operation mode setting means 22 in which an operation mode determined by the power supply frequency of the compressor 5 corresponding to the deviation obtained in the above comparison is set; and an indoor fan 2 in accordance with the temperature detected by the indoor heat exchange sensor 13. An indoor fan operation mode setting means 23 and a timer circuit 24 are built in, in which a fan operation mode determined by the number of rotations is set.

Then, according to the deviation obtained by the temperature value comparing means 21, the control section 20 selects a power supply frequency corresponding to the deviation from the compressor operation mode setting means 22, and outputs an instruction signal of the same power supply frequency to the inverter circuit 15. The compressor 5 is controlled by Further, according to the heat exchanger temperature detected by the indoor heat exchanger sensor 13, the control unit 20 selects the rotation speed of the indoor fan 2 corresponding to the detected temperature from the indoor fan operation mode setting means 23, and instructs the same rotation speed. A signal is output to the indoor fan drive circuit 5a to control the air volume of the indoor fan 2 during heating operation.

Further, in the indoor fan operation mode setting means 23 of the control unit 20, an indoor fan operation mode for low capacity heating is separately set. That is, this mode is a process of comparing the room temperature and the set temperature using the temperature value comparing means 21 as the indoor fan 2 enters a small air volume operation due to low capacity heating operation, and as a result of this deviation, the room temperature is set to the set temperature. When the temperature exceeds the temperature, the indoor fan 2 is rotated at a higher rotation speed for a certain period of time. After this step, the room temperature and the set temperature are compared again. As a result of this deviation, the room temperature is at or above the set temperature. The second deviation information is inputted into the compressor operation mode setting means 22 when the difference is reached. In this mode, during low-load heating operation, the indoor fan 2 is operated while changing the air volume between a small air volume and an increased air volume.

The operation of the air conditioner configured in this way will be explained.

An operation to start heating and a set temperature are input from the operation unit 11. As a result, the four valves of the refrigeration cycle switch to the heating side -0, and the compressor 5 starts operating. Then,
The refrigerant discharged from the compressor 5, the four-way valve, the indoor heat exchanger 1. A heating cycle that circulates through the pressure reducing device and the outdoor heat exchanger 4 is constructed. Then, the indoor fan 5 is activated, sucks indoor air from the suction port 8 on the front surface of the indoor unit, guides it to the indoor heat exchanger 1, and exchanges heat with the indoor heat exchanger 1. The warm air obtained by this heat exchange is blown out from the air outlet 10 at the bottom of the indoor unit, passing through the vertical air direction grille 17, and blown downward.

On the other hand, the control unit 20 compares the room temperature obtained by the suction temperature sensor 14 and the set temperature set by the operation unit 11 using a temperature value comparing means 21, and controls the power frequency of the compressor 5 based on this deviation. ing. Furthermore, the control unit 20 controls the rotation speed of the indoor fan 2 according to the heat exchanger temperature obtained by the indoor heat exchange sensor 13.

Here, when the heating load becomes small (for example, when the outside temperature is high), the system shifts to low-capacity heating operation.

That is, the compressor 5 is operated at a low power supply frequency. At the same time, the rotational speed of the indoor fan 2 also decreases to a small air blowing operation, and the operation shifts to the method according to the present invention. The indoor fan operation during this low capacity heating operation is shown in the flowchart shown in FIG.

Next, the operating method of the present invention will be explained according to this flowchart.

That is, the indoor fan 2 has an indoor air volume of 200, for example.
It operates with a small air volume of about m3/h. Thereafter, the room temperature detected by the suction temperature sensor 14 and the set temperature set by the operation unit 11 are compared by the temperature value comparing means 21.

Here, the small air volume of about 200 m<3>/h is likely to cause a short circuit around the indoor unit 3.

However, from the above comparison results, it can be seen whether or not the circuit is affected by a short circuit as shown by flow P in FIG. In other words, immediately after shifting to small air volume operation, if the room temperature is higher than the set temperature, the control unit 2
0 is determined to be caused by a short circuit.

Then, as shown in FIG. 4, the control unit 20 increases the rotation speed of the indoor fan 2 to operate with an increased air volume. That is, the indoor fan 2 is increased to a rotational speed at which the air volume reaches near the center of the room as shown in FIG. 3, such as the blown air P1 shown in FIG. 3, specifically, an air volume of about 300 m3/h.

Then, as timed by the timer circuit 24, this increased air volume operation continues for a certain period of time.

Through this operation, the high temperature air that has been stagnant around the indoor unit 3 due to the occurrence of the short circuit is blown out to the center of the room. This makes the indoor air temperature uniform and maintains a uniform indoor air temperature distribution.

Then, after a certain period of time has elapsed, the control section 20 uses the temperature value comparing means 21 to compare the room temperature taken in from the suction temperature sensor 14 and the set temperature.

From this result, it can be determined whether the rise in room temperature is due to an air short circuit. In other words, the temperature (
When the room temperature (room temperature) falls below the set temperature, the control unit 20 determines that the rise in room temperature is due to a short circuit.

However, if the room temperature falls below the set temperature, the control unit 20 determines that the room temperature detected by the suction sensor 14 is the true room temperature, and turns on the indoor fan according to the operation mode according to the temperature of the indoor heat exchanger 1. I will drive 3. In other words, the indoor fan 2 is operated again at the small air volume.

On the other hand, if the temperature of the air sucked into the indoor unit 3 (room temperature) does not decrease after a certain period of time has elapsed, the control unit 20 determines that the actual room temperature is higher than the set temperature, and turns on the indoor fan 3. They will either suspend operation or shift to extremely low-capacity heating operation.

By performing such operation, the true room temperature reaches the set temperature as shown in FIG. 4.

Therefore, the room temperature can be controlled to the set temperature without error even during low-load heating operation.

In addition, in the above embodiment, the indoor fan was changed to a small air volume and an increased air volume according to the comparison result between the room temperature and the set temperature, but this is not limited to this, and the flowchart of another embodiment shown in FIG. Even if the small air volume and the increased air volume are periodically repeated at a fixed time during the low-load heating operation, the same effect as in the above embodiment can be obtained. It should be noted that the configuration of the control section is the same as that of the first embodiment even for the same function, so a description of the configuration will be omitted.

In addition, in the above-described embodiment, the vertical wind direction grill 17 remains directed toward the center of the room, but during increased air volume operation, the blowing angle of the vertical wind direction grill 17 is adjusted to be directly below the indoor unit 3.
It may be changed by a drive mechanism (motor) not shown.

In this way, when the air volume is increased, the air with a lower temperature does not directly hit the person, so comfort can also be improved.

[Effects of the Invention] As described above, according to the present invention, it is possible to make the indoor temperature distribution uniform, and at the same time, perform low-load heating operation with accurate detection of the room temperature.

[Brief explanation of drawings]

Figures 1 to 4 show one embodiment of the present invention.
Figure 2 is a flowchart showing the operation of the indoor fan during low-load heating operation, Figure 2 is a block diagram showing the control system, Figure 3 is a diagram showing a state in which warm air with increased air volume is blown into the center of the room. FIG. 4 is a diagram showing changes in room temperature during low-load heating operation with small air volume and increased air volume; FIG. 5 is a flowchart showing the operation of an indoor fan according to another embodiment of the present invention; and FIG. A diagram showing room temperature changes during low-load heating operation with small air volume and increased air volume. Figure 7 is a diagram showing the configuration of a conventional human pump type air conditioner capable of heating and cooling operation. Figure 8 is a diagram showing the configuration of a conventional human-pump air conditioner capable of heating and cooling operation. FIG. 9 is a diagram showing an air short circuit that occurs during heating operation, and FIG. 9 is a diagram showing room temperature changes during low-load heating operation. 1... Indoor heat exchanger, 2... Indoor fan, 3...
・Indoor unit (air conditioner body) 8... Suction port,
10... Air outlet, 20... Control unit.

Claims (1)

[Claims] An indoor fan built into the main body of the air conditioner that sucks indoor air from the suction port of the main body, guides it to the indoor heat exchanger, and blows it out from the air outlet of the main body during low-load heating operation, the air volume is small and the air volume is low. An indoor fan operating method for an air conditioner characterized by operating the fan while changing the air volume to a higher level.