JPH07248141A - Controller for air conditioner - Google Patents

Abstract

PURPOSE:To provide a controller for an air conditioner which ensures comfortable control without deteriorating dehumidification performance upon cooling operation under environment where fresh air temperature is relatively low. CONSTITUTION:An air conditioner comprises a compressor, a four-way valve, an outdoor heat exchanger, pressure reducing means, and an indoor heat exchanger, all being coupled in this order, further including a fan for the outdoor heat exchanger and a fan for the indoor heat exchanger. There are further provided input/output means 11, operation frequency detection means 12, target temperature set means 13, mode decision means 14, mode switching means 15, operation frequency set means 16, compressor driving means 17, indoor fan revolution set means 18, indoor fan driving means 19, outdoor fan driving means 20, and a control part 21. The target temperature is set to be a cooling operation mode higher than the set temperature. As the temperature reaches the target temperature and the operation frequency reaches a predetermined frequency or lower, the target temperature is switched to a dehumidifying operation mode of the set temperature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner control device having a dehumidifying operation function.

[0002]

2. Description of the Related Art Conventionally, a compressor 1, a four-way valve 2, an outdoor heat exchanger 3, a pressure reducing means 4, and an indoor heat exchanger 5 of an indoor unit are sequentially connected, and a fan 6 is connected to the outdoor heat exchanger 3 to heat the indoor heat. As shown in FIG. 5, an air conditioner control device including a fan 7 in the exchanger 5 includes an input / output unit 11 for exchanging input / output information, data such as temperature and the like with the indoor unit, and the input / output unit. The operating frequency setting means 16 for varying the operating frequency based on the deviation between the set temperature from 11 and the indoor temperature data, the compressor driving means 17 for inverter driving at the operating frequency, and the fan 6 of the outdoor heat exchanger 3. The outdoor fan drive means 20 for driving, the rotation speed switching means 18 for switching the rotation speed of the fan 7 of the indoor heat exchanger 5, the indoor fan drive means 19 for driving the fan 7 at the switched rotation speed, and each means are controlled. Control unit 21 In the cooling or heating operation mode, the operating frequency of the compressor 1 is changed according to the deviation between the set temperature and the indoor temperature data to change the capacity of the compressor, and the fan of the indoor unit is changed. The number of rotations was set to a value (strong, medium, weak, etc.) set by the user to switch so that cold air or warm air could reach a certain distance. Further, in the dehumidification operation mode, the operation frequency of the compressor 1 is controlled to a predetermined low frequency or less, and the rotation speed of the fan of the indoor unit is set to be lower than that in the cooling or heating operation mode. However, in the cooling operation when the air conditioning load is relatively light, such as in an environment where the outside air temperature is relatively low, the compressor is operated for a long time with a low operating frequency, or the compressor is repeatedly operated intermittently. In spite of this, the dehumidifying performance of the indoor heat exchanger is significantly deteriorated because the rotation speed of the indoor unit fan is raised to a certain extent during cooling operation, causing an abnormal rise in indoor humidity and abnormal fluctuations. There was a problem that impaired comfort. In addition, when the dehumidification operation is set from the beginning in order to prevent abnormal rise in indoor humidity and abnormal fluctuation, the target temperature does not reach the target temperature because the fan speed of the indoor unit and the operating frequency of the compressor are low. was there.

[0003]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problem and reduces the dehumidifying performance of the indoor heat exchanger even during cooling operation when the air conditioning load is relatively light, such as in an environment where the outside air temperature is relatively low. It is an object of the present invention to provide a control device for an air conditioner that does not impair comfortability by preventing an abnormal increase in indoor humidity and an abnormal fluctuation.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention uses a pressure reducing means 4 to discharge the refrigerant discharged from a compressor 1 through a four-way valve 2, an outdoor heat exchanger 3, etc. The indoor heat exchanger 5 is supplied, and the outdoor heat exchanger 3 is provided with the fan 6.
In an air conditioner having a fan 7 in the indoor heat exchanger 5, an input / output unit 11 for exchanging input / output information, data such as temperature and the like with the indoor unit, and a frequency detection unit for detecting an operating frequency of the compressor. 12, a target temperature setting means 13 for setting a target temperature based on the set temperature from the input / output means 11, the operating frequency from the frequency detection means 12, and the like.
A mode determination means 14 for determining an operation mode based on the operating frequency from the frequency detection means 12 and room temperature data from the input / output means, a mode switching means 15 for switching the mode according to the determination result, and the operation of the compressor. The frequency setting means 16 for setting the frequency, the compressor driving means 17 for driving the compressor to the frequency, the rotation speed setting means 18 for setting the rotation speed of the fan 7 of the indoor unit, and the set rotation speed. Fan drive means 19 for driving the fan 7 and fan drive means 20 for driving the fan 6 of the outdoor heat exchanger.
And a control unit 21 that controls each means, and when the cooling operation is started by the input information from the indoor unit, the target temperature is set to a cooling operation mode higher than the set temperature input from the indoor unit, and the target temperature The target temperature is switched to the dehumidifying operation mode of the set temperature when the compressor operating frequency becomes equal to or lower than the predetermined frequency, and the target temperature exceeds the predetermined temperature during the dehumidifying operation. Control is performed so as to switch to a cooling operation mode higher than the set temperature input from the indoor unit.

[0005]

With the above configuration, when the cooling operation is started by the input information from the indoor unit, the cooling operation mode is set higher than the set temperature at which the target temperature is input, and the difference between the target temperature and the room temperature is set. The operation frequency of the compressor is controlled by the target temperature, and when the operation frequency of the compressor becomes equal to or lower than the predetermined frequency, the target temperature is switched to the dehumidification operation mode at the set temperature, and the operation frequency of the compressor is set to the predetermined value. The temperature is controlled to be lower than the low frequency, the fan of the indoor unit is controlled to rotate lower than in the cooling operation mode, and when the temperature exceeds the predetermined temperature during the dehumidifying operation, the target temperature is input again. It is controlled to switch to the cooling operation mode higher than the temperature.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a control device for an air conditioner according to the present invention will be described in detail below with reference to the drawings. 1 is a control block diagram showing an embodiment of a control device for an air conditioner according to the present invention, and FIG. 2 shows a refrigeration cycle of the air conditioner. First, the refrigeration cycle of FIG. 2 and the like will be described. Reference numeral 1 is a compressor driven by an inverter. 2 is a four-way valve,
The flow direction of the compressed refrigerant is controlled, and the refrigerant to be compressed is sent to the outdoor heat exchanger 3 during the heating operation and to the indoor heat exchanger 5 during the cooling operation. The outdoor heat exchanger 3 radiates the heat of the refrigerant gas into the air or absorbs the heat in the air into the refrigerant. Decompression means 4 forms a thin tube for decompressing the refrigerant to be compressed, and limits the flow rate of the refrigerant circulating in the indoor heat exchanger 5. The indoor heat exchanger 5 absorbs heat in the air into the refrigerant or radiates the heat of the refrigerant into the air in the room. An outdoor fan 6 sends air to the outdoor heat exchanger 3. An indoor fan 7 sends air to the indoor heat exchanger 5.

Next, in the above refrigeration cycle, the control device of the air conditioner shown in FIG. 1 will be described below. An input / output unit 11 exchanges information such as setting information and indoor temperature data with the indoor unit. Reference numeral 12 is an operating frequency detecting means for detecting the operating frequency of the compressor 1. Reference numeral 13 denotes a target temperature setting means, which sets a target temperature for actual operation based on the set temperature input from the input / output means 11 and the operating frequency from the operating frequency detecting means 12. Reference numeral 14 denotes an operation mode determination means, which determines the operation mode based on the room temperature data input from the input / output means 11, the difference between the set temperature and the room temperature data, and the operation frequency from the operation frequency detection means 12. Deciding. Reference numeral 15 is a mode switching means for switching to the operation mode judged by the operation mode judgment means 14. 16 is an operating frequency setting means,
The operating frequency of the compressor 1 is set based on the difference between the set temperature and the room temperature data. 17 is a compressor driving means,
The compressor 1 is driven at the operating frequency set by the operating frequency setting means. Reference numeral 18 denotes an indoor fan rotation speed switching means, which switches the rotation speed of the fan based on the air flow rate setting information input from the input / output means 11 and the operation mode determined by the operation mode determination means 14. Reference numeral 19 denotes an indoor fan driving means, which drives the fan at the switched rotation speed. An outdoor fan drive unit 20 drives the outdoor fan 6. A control unit 21 controls each means.

Next, the operation of the above structure will be described. FIG. 3 is a graph showing changes in the room temperature, the operating frequency of the compressor, and the rotation speed of the indoor fan from the start of the cooling operation until the set target temperature is reached. Now, when the operation mode and the target set temperature Ts are input from the input / output means, they sequentially operate as shown in the flowchart for explaining the operation shown in FIG. When the cooling operation is started at time t0, in step 1 (ST1), the target temperature Tm is set to the set temperature Ts + α, and as the difference (Tm-Tr) between the target temperature Tm and the indoor temperature data Tr becomes smaller. The operating frequency fc is lowered. In step 2 (ST2), the room temperature Tr is monitored, and operation is performed in the cooling operation mode until the room temperature reaches Tm. When Tr = Tm at time t1, step 3 (ST
Then, the operation frequency f of the compressor is monitored and the operation is continued in the cooling operation mode until the operation frequency f becomes equal to or lower than the predetermined frequency fc. When f <fc at time t2, the process proceeds to step 4 (ST4), the target temperature Tm is set to the original set temperature Ts, the operating frequency f of the compressor is controlled below a predetermined low frequency, and the fan 7 is set to a predetermined low temperature. The dry operation is switched to the rotation speed Nd. Step 5 (ST
In 5), the room temperature Tr is monitored, and when the temperature exceeds the target temperature Tm, that is, the set temperature Ts by 3 ° C. or more, step 1 (ST
The cooling operation of 1) is switched to, and this is repeated.

[0009]

As described above, according to the control device for an air conditioner of the present invention, the cooling operation mode in which the target temperature is higher than the input set temperature is set, and the difference between the target temperature and the room temperature is large. The operating frequency of the compressor is controlled by the above, and when the target temperature is reached and the operating frequency of the compressor becomes equal to or lower than the predetermined frequency, the target temperature is switched to the dehumidifying operation mode equal to the set temperature and the operating frequency of the compressor is set to the predetermined value. The frequency of the indoor unit fan is controlled to rotate at a lower frequency than that in the cooling operation mode, so when the operating frequency of the compressor is low, the rotation speed of the indoor unit fan is increased to increase the dehumidifying capacity. Comfortable control that does not deteriorate can be realized. When the temperature exceeds the target temperature during dehumidifying operation, the target temperature is controlled to switch to the cooling operation mode which is set higher than the input set temperature. Control can be realized.

[Brief description of drawings]

FIG. 1 is a control block diagram showing an embodiment of a control device for an air conditioner according to the present invention.

FIG. 2 is a diagram showing a refrigeration cycle of the air conditioner according to the present invention.

FIG. 3 is a graph showing changes in the room temperature of the air conditioner controller according to the present invention, the operating frequency of the compressor, and the rotation speed of the indoor fan.

FIG. 4 is a flow chart for explaining the operation of the control device for an air conditioner according to the present invention.

FIG. 5 is a control block diagram showing a control device for a conventional air conditioner.

[Explanation of symbols]

 1 compressor 2 four-way valve 3 outdoor heat exchanger 4 pressure reducing means 5 indoor heat exchanger 6 outdoor fan 7 indoor fan 11 input / output means 12 operating frequency detecting means 13 target temperature setting means 14 operating mode determining means 15 mode switching means 16 operating Frequency setting means 17 Compressor driving means 18 Indoor fan rotation speed switching means 19 Indoor fan driving means 20 Outdoor fan driving means 21 Control section

Claims (1)

[Claims] 1. An air conditioner for supplying refrigerant discharged from a compressor to an indoor heat exchanger of an indoor unit by a pressure reducing means via a four-way valve, an outdoor heat exchanger, etc. Input / output means for exchanging data such as temperature,
Frequency detecting means for detecting the operating frequency of the compressor,
Based on the target temperature setting means for setting the target temperature based on the set temperature from the input / output means, the operating frequency from the frequency detecting means, etc., the operating frequency from the frequency detecting means and the room temperature data from the input / output means. A mode determining means for determining an operation mode, a mode switching means for switching the mode according to the determination result, a frequency setting means for setting an operating frequency of the compressor, and a compressor driving means for driving the compressor to the frequency. The input information from the indoor unit is composed of a rotation speed setting unit that sets the rotation speed of the fan of the indoor unit, a fan driving unit that drives the fan to the set rotation speed, and a control unit that controls each unit. When the cooling operation is started, the target temperature is set to a cooling operation mode higher than the set temperature input from the indoor unit, the target temperature is reached, and the operating frequency of the compressor is set to a predetermined value. If the target temperature is below the wave number, the target temperature switches to the dehumidifying operation mode of the set temperature, and if the target temperature exceeds the predetermined temperature during the dehumidifying operation, the target temperature is again set higher than the set temperature input from the indoor unit. An air conditioner controller characterized by switching to an operation mode.