JP3199746B2 - Multi-room air conditioner - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a control device for a multi-room air conditioner, and more particularly to a multi-room air conditioner that has reduced power consumption while ensuring the performance of an indoor unit.

BACKGROUND ART Conventionally, as described in Japanese Patent Publication No. 4-32298, a variable displacement compressor used in a multi-room air conditioner is set so that a low pressure becomes a set pressure during cooling, and a high pressure becomes a set pressure during heating. The capacity is controlled so that

In the above-mentioned conventional technology, the heat source temperature of each indoor heat exchanger can be kept substantially constant, and the blowout temperature of each indoor unit is close to the heat source temperature if the imbalance of the refrigerant flow to each indoor unit does not occur. This is a control method with good controllability without causing a shortage of capacity. However, reducing power consumption has not been considered.

Some indoor units connected to the multi-room air conditioner have different indoor unit capacities and models, and some of these indoor fan airflows are not proportional to the indoor capacity. For example, if only an indoor unit having a large amount of indoor fan airflow compared to the indoor unit capacity is operated with a compressor capacity corresponding to the indoor unit capacity, the low pressure pressure increases in cooling and the high pressure pressure decreases in heating. Since the pressure is controlled to the set pressure, the capacity of the compressor is increased. As a result, the indoor unit has a capacity higher than the indoor unit capacity, and the power consumption also increases.

Also, as described in Japanese Patent Publication No. 4-71139, distribution of the flow rate of the refrigerant flowing through each indoor unit of the multi-room air conditioner is such that the cooling degree of the refrigerant at the outlet side of the indoor heat exchanger of each indoor unit is set at the time of cooling. During heating, an electrically operated valve provided on the liquid pipe side of each indoor unit and having an adjustable valve opening is used so that the degree of supercooling on the outlet side of the indoor heat exchanger becomes a set value. Further, a temperature sensor is attached to the refrigerant pipe to detect the temperature of the refrigerant at the outlet of the indoor heat exchanger.

During the cooling operation, moisture in the air adheres to the refrigerant pipe to which the temperature sensor is attached, and the moisture enters the temperature sensor and makes an erroneous detection. It may not be detected.
When this detection failure occurs, the detection error of the degree of superheat of the refrigerant also increases, and the distribution of the refrigerant to the indoor units cannot be performed satisfactorily.

For example, in the related art in which the degree of superheat of the refrigerant is detected to be a set value when the degree of superheat of the refrigerant is detected to be larger than the actual level, the amount of refrigerant is increased by opening the indoor refrigerant flow control valve of the indoor unit. Insufficient ability.

When the degree of superheat of the refrigerant is detected to be smaller than the actual value, the indoor refrigerant flow regulating valve of the indoor unit is throttled, so that the performance of the indoor unit is insufficient.

 During the heating operation, there are the following problems.

(1) When the indoor refrigerant flow control valve is throttled to increase the degree of supercooling and the refrigerant flow is reduced, the refrigerant temperature at the outlet of the indoor exchanger approaches the intake air temperature, and the opening degree of the indoor refrigerant flow control valve is small. By the way, even if the opening degree is changed, the refrigerant temperature at the outlet of the indoor heat exchanger hardly changes.

As a result, the indoor refrigerant flow control valve is excessively throttled, and the liquid refrigerant is excessively accumulated in the indoor heat exchanger, so that the amount of refrigerant circulating in the refrigeration cycle is insufficient, and the performance of other indoor units is reduced.

(2) The stoppage of the indoor refrigerant flow control valve is controlled to be slightly opened from the viewpoint of power saving of the refrigerant flowing to the stopped indoor unit.

However, when the opening degree of the indoor refrigerant flow control valve is slightly opened and the flow rate of the refrigerant is very small, the refrigerant temperature at the outlet of the indoor heat exchanger hardly changes from the temperature when the refrigerant does not flow.
Therefore, when the indoor refrigerant flow control valve is fully closed, the refrigerant accumulates as a liquid in the indoor heat exchanger, and the refrigerant circulating in the refrigeration cycle runs short in the same manner as described above, causing a decrease in the capacity of the operating indoor unit. .

Therefore, conventionally, it is difficult to control the indoor refrigerant flow control valve so as not to be fully closed in the vicinity of the slightly opened state.

However, even if the minimum opening degree is provided, the amount of the liquid refrigerant accumulated in the indoor heat exchanger is unknown, so that the amount of the refrigerant circulating in the refrigeration cycle is insufficient, and an indoor unit with insufficient capacity is generated.

Further, as described in JP-A-3-294752, the distribution of the flow rate of the refrigerant flowing through each indoor unit during heating is set so that the temperature difference between the blown air temperature and the intake air temperature of each indoor unit becomes a set value. The adjustment is performed by an indoor refrigerant flow rate adjustment valve provided on the liquid pipe side in each indoor unit and capable of adjusting the valve opening.

In this prior art, the distribution of the outlet temperature and the short circuit in which the outlet air flows to the suction side as it is cannot distribute the refrigerant in proportion to the capacity of the indoor unit, resulting in an indoor unit with insufficient capacity.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems of the related art, control the capacity of a compressor so that the total capacity of an operating indoor unit becomes a total value of required capacity, and achieve power consumption corresponding to the required capacity of the indoor unit. An object of the present invention is to provide a multi-room air conditioner that has a low consumption capacity in operation, particularly in heating operation.

Another object of the present invention is to provide a multi-room air conditioner in which the amount of refrigerant circulating in a refrigeration cycle is ensured to prevent a capacity shortage.

DISCLOSURE OF THE INVENTION A multi-room air conditioner according to the present invention includes a means for determining cooling or heating capacity based on a temperature difference between an intake air temperature and an outlet air temperature of an indoor unit, and a target cooling system based on a difference between the intake air temperature and a room temperature set value. Or means for determining the heating capacity, and controls the operating capacity of the variable displacement compressor so that the total value of the cooling or heating capacity becomes the total value of the target cooling or heating capacity.

Further, the air conditioner includes means for determining a cooling capacity based on a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, and means for determining a target cooling capacity based on a difference between the suction air temperature and a room temperature set value. Is controlled to be the total value of the target cooling capacity.

Further, means for determining a cooling capacity from the temperature difference between the suction air temperature and the blow-out air temperature of the indoor unit, the air volume of the indoor unit, the density of the air, the specific heat of the air, and the sensible heat ratio, Means for determining a target cooling capacity based on a difference from the room temperature set value, wherein the operating capacity of the variable displacement compressor is controlled such that the total value of the cooling capacity becomes the total value of the target cooling capacity.

Further, a means for determining a heating capacity from a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and a specific heat of the air, and a method of calculating a suction air temperature and a room temperature set value. Means for determining the target heating capacity based on the difference, and controlling the operating capacity of the variable displacement compressor such that the total value of the heating capacity becomes the total value of the target heating capacity.

Further, means for determining the cooling capacity based on the temperature difference between the suction air temperature and the blow-out air temperature of the indoor unit, and when the difference between the suction air temperature and the room temperature set value is greater than 2 to 4 ° C., the target cooling capacity is determined by the indoor unit. Rated cooling capacity, 2
Means for setting the target cooling capacity to be equal to or less than the rated cooling capacity of the indoor unit when the temperature is equal to or lower than 4 ° C., and operating the variable capacity compressor so that the total value of the cooling capacity becomes the total value of the target cooling capacity. Control.

Further, a means for determining the heating capacity based on the temperature difference between the intake air temperature and the blow-out air temperature of the indoor unit, and when the difference in the intake air temperature from the room temperature set value is greater than 2 to 4 ° C, the target heating capacity is set to the indoor unit. Rated heating capacity, 2
Means for setting the target heating capacity to be equal to or less than the rated heating capacity of the indoor unit when the temperature is equal to or lower than 4 ° C., and operating the variable capacity compressor so that the total value of the heating capacity becomes the total value of the target heating capacity. Control.

Further, in the above, the opening degree of the indoor refrigerant flow control valve is controlled so that the cooling capacity becomes the target cooling capacity.

Further, in the above, the opening degree of the indoor refrigerant flow control valve is controlled so that the heating capacity becomes the target heating capacity.

Further, a means for determining a heating capacity from a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and a specific heat of the air, and a method of calculating a suction air temperature and a room temperature set value. Means for determining the target heating capacity by the difference, means for controlling the operating capacity of the variable capacity compressor so that the total value of the heating capacity becomes the total value of the target heating capacity, and means for controlling the indoor capacity so that the heating capacity becomes the target heating capacity. Means for controlling the opening of the refrigerant flow control valve, and means for making the maximum opening of the indoor refrigerant flow control valve smaller than the full opening when the discharge pressure of the variable displacement compressor is equal to or lower than a predetermined value.

Further, a means for determining a heating capacity from a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and a specific heat of the air, and a method of calculating a suction air temperature and a room temperature set value. Means for determining the target heating capacity by the difference, means for controlling the operating capacity of the variable capacity compressor so that the total value of the heating capacity becomes the total value of the target heating capacity, and means for controlling the indoor capacity so that the heating capacity becomes the target heating capacity. Means for controlling the opening of the refrigerant flow regulating valve and the discharge pressure of the variable displacement compressor
A pressure switch that is turned off when the pressure becomes 15 to 20 kg / cm ² or less, and the maximum opening of the indoor refrigerant flow regulating valve when the pressure switch is turned off is (full opening × 0.5).

Further, a means for determining a heating capacity from a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and a specific heat of the air, and a method of calculating a suction air temperature and a room temperature set value. Means for determining the target heating capacity by the difference, means for controlling the operating capacity of the variable capacity compressor so that the total value of the heating capacity becomes the total value of the target heating capacity, and means for controlling the indoor capacity so that the heating capacity becomes the target heating capacity. Means are provided for controlling the opening of the refrigerant flow control valve, and means for making the maximum opening of the indoor refrigerant flow control valve smaller than the full opening when the intake air temperature is equal to or lower than a predetermined value.

Further, a means for determining a heating capacity from a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and a specific heat of the air, and a method of calculating a suction air temperature and a room temperature set value. Means for determining the target heating capacity by the difference, means for controlling the operating capacity of the variable capacity compressor so that the total value of the heating capacity becomes the total value of the target heating capacity, and means for controlling the indoor capacity so that the heating capacity becomes the target heating capacity. Means for controlling the degree of opening of the refrigerant flow control valve.
When the temperature is equal to or lower than 25 ° C., the maximum opening of the indoor refrigerant flow control valve is set to (full opening × 0.5).

Further, in the above description, the cooling capacity is determined by correcting with the correction coefficient of the temperature distribution of the blown air temperature and the indoor air flow coefficient.

Further, in the above description, the heating capacity is determined by correcting the correction coefficient of the temperature distribution of the blown air temperature and the indoor air flow coefficient.

Further, a means for determining a heating capacity from a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and a specific heat of the air, and a method of calculating a suction air temperature and a room temperature set value. Means for determining the target heating capacity by the difference, means for controlling the operating capacity of the variable capacity compressor so that the total value of the heating capacity becomes the total value of the target heating capacity, and a liquid tank installed in the outdoor unit During the heating operation, the opening degree of the indoor refrigerant flow control valve of the indoor unit is changed according to the opening degree of the outdoor refrigerant flow control valve.

Further, in the above, when the opening degree of the outdoor refrigerant flow regulating valve is equal to or less than (0.5 × full opening degree), the minimum opening degree of the indoor refrigerant flow regulating valve is set to (0.1 × full opening degree), and the outdoor refrigerant flow regulating valve Is greater than (0.8 x full opening), the minimum opening of the indoor refrigerant flow control valve is (0.4 x full opening) and the outdoor refrigerant flow regulating valve is (0.5 x full opening) ) To (0.8
X Full opening), the minimum opening of the indoor refrigerant flow control valve is a value from (0.1 x full opening) to (0.4 x full opening), which is proportional to the opening of the outdoor refrigerant flow adjusting valve. And

 With the above configuration, the following operation is performed.

Means for determining the cooling or heating capacity based on the temperature difference between the intake air temperature and the blow-out air temperature of the indoor unit is to detect the temperatures of the suction unit and the blow-out unit of the indoor unit using a temperature sensor and to determine the value of the difference. Means to calculate the cooling or heating capacity currently in operation. Specifically, a microcomputer provided in an indoor controller or an outdoor controller is used.

Similarly, the means for determining the target cooling or heating capacity by the difference between the suction air temperature and the set value is to determine the target cooling or heating capacity from the difference between the already detected suction air temperature and the set room temperature. That is, the specific relationship is determined in advance by a microcomputer provided in the indoor controller or the outdoor controller.

Controlling the operating capacity of the variable displacement compressor so that the total value of the cooling or heating capacity becomes the total value of the target cooling or heating capacity means that the cooling or heating capacity of each indoor unit calculated above and the cooling capacity or heating capacity calculated above are determined. Sends the value of the target cooling or heating capacity of each indoor unit to the outdoor unit controller, and controls the operating capacity of the variable displacement compressor in the outdoor unit with the total value of both of them. Variable by the microcomputer provided in the outdoor controller from the deviation between the calculated total value of the cooling or heating capacity of each indoor unit and the target total value of the cooling or heating capacity of each indoor unit determined This is performed by obtaining the motor speed of the displacement compressor and controlling the displacement of the variable displacement compressor.

By the above, the variable capacity compressor will not be operated with a capacity greater than the total capacity of the operated indoor units,
The compressor is operated with a compressor capacity corresponding to the total value of the required capacity of each indoor unit. Therefore, the multi-room air conditioner can be operated with power consumption corresponding to the required capacity of each indoor unit.

Further, in the above, the capacity of the variable displacement compressor is controlled from the deviation between the total value of the cooling capacity of each indoor unit calculated only during the cooling operation and the predetermined total value of the cooling capacity targeted for each indoor unit. Thus, power consumption can be effectively reduced.

Further, means for determining the cooling capacity from the temperature difference between the intake air temperature and the blow-out air temperature of the indoor unit, the air volume of the indoor unit, the density of air, the specific heat of air, and the sensible heat ratio are: The temperature of the suction section and the blow-out section are detected using a temperature sensor, and the cooling capacity during the current operation is determined from the value of the difference, the air volume of the indoor unit, the density of the air, the specific heat of the air, and the sensible heat ratio. This means calculating, and specifically, a microcomputer provided in an indoor controller or an outdoor controller is used. Thereby, the calculation of the cooling capacity can be accurately performed.

Further, the means for determining the heating capacity from the temperature difference between the suction air temperature and the blow-out air temperature of the indoor unit, the air volume of the indoor unit, the density of the air, and the specific heat of the air include the suction unit and the blow-out unit of the indoor unit. Means the temperature of the current operation is calculated from the difference value, the air volume of the indoor unit, the density of the air, and the specific heat of the air. A microcomputer provided in an indoor controller or an outdoor controller is used. Thereby, the calculation of the heating capacity can be performed accurately.

Furthermore, the difference between the intake air temperature and the room temperature set value is 2
Means for setting the target cooling capacity as the rated cooling capacity of the indoor unit when the cooling capacity is greater than or equal to 4 ° C. and setting the target cooling capacity as the rated cooling capacity or less for the indoor unit when the temperature is 2 to 4 ° C. or less,
The suction unit of the indoor unit is detected using a temperature sensor, and if the value is larger than the room temperature set value by 2 to 4 ° C., the cooling load is large, so the target cooling capacity is set to the value of the rated cooling capacity of the indoor unit. When the difference from the set value is 2 to 4 ° C. or less, it means that the target cooling capacity is determined as a value equal to or less than the rated cooling capacity because the cooling load is small. Specifically, the target cooling capacity is provided in the indoor controller or the outdoor controller. Is determined by the microcomputer. As a result, the target cooling capacity can be appropriately determined according to the room temperature set value (cooling load).

Furthermore, when the difference between the intake air temperature from the set room temperature and the intake air temperature is greater than 2 to 4 ° C, the target heating capacity is set to the rated heating capacity of the indoor unit. The means to determine the heating capacity or less means that the suction unit of the indoor unit is detected using a temperature sensor, and if the room temperature set value is greater than 2 to 4 ° C., the heating load is large, so the target heating capacity is set to the indoor unit. When the difference from the room temperature set value is 2 to 4 ° C. or less, since the heating load is small, it means that the target heating capacity is determined as a value equal to or less than the rated heating capacity. The determination is made by the microcomputer provided in the indoor controller or the outdoor controller. Thereby, the target heating capacity can be appropriately determined according to the room temperature set value (heating load).

Further, in the above, the cooling capacity of each indoor unit can be directly controlled by controlling the opening degree of the indoor refrigerant flow control valve so that the cooling capacity becomes the target cooling capacity. Can be kept short.

Further, in the above, the heating capacity of each indoor unit can be directly controlled by controlling the opening degree of the indoor refrigerant flow control valve so that the heating capacity becomes the target heating capacity. Can be kept short.

Further, in the heating operation, when the discharge pressure of the variable capacity compressor is equal to or less than a predetermined value, the means for making the maximum opening degree of the indoor refrigerant flow control valve smaller than the full opening degree includes a pressure switch on the discharge side of the compressor. Attach the signal to the outdoor controller and detect that the discharge pressure has fallen below the predetermined value by turning the pressure switch off or on. This means that the opening degree is smaller than the full opening degree, and specifically, is determined by a microcomputer provided in an indoor controller or an outdoor controller. As a result, the flow path resistance of the indoor refrigerant control valve increases, and the discharge pressure increases, and accordingly, the condensing pressure, that is, the condensing temperature increases. Since the condensation temperature is the heat source temperature, the heating capacity also increases. Therefore, the capacity of the indoor unit increases, and the operating capacity of the compressor is reduced by the increased amount, so that power saving can be achieved.

Further, in the above, a pressure switch which is turned off when the discharge pressure of the variable capacity compressor becomes 15 to 20 kg / cm ² or less, which is a normal use pressure when HCF22R or 407C is used as the refrigerant, When is turned off, the maximum opening of the indoor refrigerant flow control valve is smaller than the full opening and the opening is not too restrictive (full opening x 0.5), so the capacity of the indoor unit can be increased and the increase The operating capacity of the compressor can be reduced by the amount.

Further, in the heating operation, the means for making the maximum opening of the indoor refrigerant flow control valve smaller than the full opening when the suction air temperature is equal to or lower than a predetermined value is to detect the suction unit of the indoor unit using a temperature sensor. When the value is equal to or less than a predetermined value, it means that the maximum opening degree of the indoor refrigerant flow control valve is smaller than the full opening degree, and specifically, provided in an indoor controller or an outdoor controller. Is determined by the microcomputer. As a result, the capacity of the indoor unit is increased as described above, the operating capacity of the compressor is reduced by the increased amount, and power saving can be achieved.

Further, in the above, the suction air temperature is 20 to
When the heating load of 25 ° C or less is relatively large, the maximum opening of the indoor refrigerant flow control valve is smaller than the full opening and the opening is not too narrow (full opening x 0.5). The capacity of the indoor unit can be increased, and the operating capacity of the compressor can be reduced by the increased amount.

Further, in the above, the cooling capacity is determined by correcting the correction coefficient of the temperature distribution of the blown-out air temperature and the indoor air flow coefficient, so that the environment (humidity, short circuit, etc.) of the room in which the indoor unit is installed and It is possible to correct the characteristics of the indoor unit (such as the distribution of the indoor fan air volume and the blown air temperature). As a result, the indoor functional power can be accurately detected, and the indoor functional power can be reliably ensured.

Furthermore, in the above, since the heating capacity is determined by correcting the correction coefficient of the temperature distribution of the blown-out air temperature and the indoor air volume coefficient, the calculation of the heating capacity of the indoor unit is made more accurate, and the indoor temperature with high accuracy is obtained. The control of the refrigerant flow control valve and the compressor capacity can be realized.

Further, during the heating operation, the opening degree of the indoor refrigerant flow control valve of the indoor unit is changed according to the opening degree of the outdoor refrigerant flow control valve, so that the liquid refrigerant is excessively accumulated in the indoor heat exchanger and the refrigerant is insufficient. Is eliminated. Therefore, shortage of the heating capacity of the indoor unit can be prevented.

Furthermore, in the above, when the opening degree of the outdoor refrigerant flow control valve is equal to or less than the normal use range (0.5 × full opening), the minimum opening degree of the indoor refrigerant flow control valve is set to (0.1 × full opening). When the opening of the outdoor refrigerant flow control valve is equal to or greater than (0.8 x full opening), the minimum amount of the indoor refrigerant flow adjusting valve is set to (0.4 x full opening) because the refrigerant is insufficient, and the outdoor refrigerant flow is adjusted. When the valve opening is between (0.5 x full opening) and (0.8 x full opening), the minimum opening of the indoor refrigerant flow control valve is set to (0.1 x
X Full opening) to (0.4 x full opening) and a value proportional to the opening of the outdoor refrigerant flow control valve. The shortage is eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a configuration of a refrigeration cycle of a multi-room air conditioner according to one embodiment of the present invention.

FIG. 2 is a graph showing the relationship between the difference between the indoor unit intake air temperature and the set temperature and the target cooling capacity ratio of the indoor unit.

FIG. 3 is a block diagram showing a compressor capacity control method during a cooling operation.

FIG. 4 is a block diagram showing a method of controlling the opening degree of the indoor refrigerant flow control valve during the cooling operation.

FIG. 5 is a graph showing the relationship between the difference between the indoor unit intake air temperature and the set temperature and the target heating capacity ratio of the indoor unit.

FIG. 6 is a block diagram showing a compressor capacity control method during the heating operation.

FIG. 7 is a block diagram showing a configuration of a refrigeration cycle of a multi-room air conditioner according to another embodiment of the present invention.

FIG. 8 is a graph showing the relationship between the operation of the pressure switch with respect to the discharge pressure and the maximum opening of the indoor refrigerant flow control valve.

FIG. 9 is a graph showing the relationship between the indoor suction air temperature and the maximum opening of the indoor refrigerant flow control valve.

FIG. 10 is a plan view showing a component arrangement of a control board of an indoor controller of an indoor unit.

FIG. 11 is a relationship diagram showing ON / OFF combinations of DIP switches on the control board and operation coefficients.

FIG. 12 is a block diagram showing a configuration of a refrigeration cycle of the multi-room air conditioner during a heating operation according to one embodiment of the present invention.

FIG. 13 is a graph showing the relationship between the opening degree of the outdoor refrigerant flow regulating valve, the minimum opening degree of the indoor refrigerant flow regulating valve, and the opening degree of the indoor refrigerant flow regulating valve of the stopped indoor unit.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

One embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a block diagram showing a configuration of a refrigeration cycle of a multi-room air conditioner according to one embodiment of the present invention. FIG. 2 is a graph showing the deviation between the indoor unit intake air temperature and the set temperature on the horizontal axis, and the relationship between the target cooling capacity ratio of the indoor unit and the vertical axis. FIG. 3 is a block diagram showing a compressor capacity control method during a cooling operation. FIG. 4 is a block diagram showing a method of controlling the opening degree of the indoor refrigerant flow control valve during the cooling operation. FIG. 5 is a graph showing the deviation between the indoor unit suction air temperature and the set temperature on the horizontal axis, and the relationship between the target heating capacity ratio of the indoor unit and the vertical axis. FIG. 6 is a block diagram showing a compressor capacity control method during the heating operation.

The outdoor unit 100 and the indoor units 200 and 300 have a gas pipe 121 and a liquid pipe.
Connected by 122. The outdoor unit 100 includes a compressor 105 having a variable motor rotation speed, a four-way valve 106, and an outdoor heat exchanger 10.
1. An outdoor refrigerant flow control valve 102, an outdoor fan 103, an accumulator 104, an outdoor controller 151, and a discharge temperature detector 115.

The outdoor controller 151 receives the signal of the discharge temperature detector 115, and outputs a signal for controlling the rotation speed of a motor (not shown) of the compressor 105 and the outdoor refrigerant flow control valve 102.

The indoor unit 200 includes an indoor heat exchanger 201, an indoor refrigerant flow control valve.
202, an indoor fan 203, temperature detectors 204, 206, 207 and an indoor controller 208.

The indoor controller 208 receives the signals of the temperature detectors 204, 206, and 207 and controls the opening of the indoor refrigerant flow control valve 202.

Similarly, the indoor unit 300 includes an indoor heat exchanger 301, an indoor refrigerant flow control valve 302, an indoor fan 303, and temperature detectors 304, 306, and 30.
7 and an indoor controller 308. The indoor controller 308 receives the signals of the temperature detectors 304, 306, and 307 and controls the opening of the indoor refrigerant flow control valve 302.

Temperature sensors 204 and 304 are indoor heat exchangers 201 and 301, respectively.
And detects the temperature of the liquid-side refrigerant. Temperature sensors 206 and 306 are indoor units 200 and 300, respectively.
Is detected. Temperature sensors 207, 3
Reference numeral 07 indicates the temperature of the blown air from the indoor units 200 and 300, respectively.

The indoor controllers 208 and 308 and the outdoor controller 151 are connected by a transmission line and exchange various signals.

 The operation of each unit during the cooling operation will be described.

Solid arrows in the gas pipe 121 and the liquid pipe 122 indicate the flow direction of the refrigerant during the cooling operation, and solid arrows in the indoor units 200 and 300 indicate the air flow directions.

The refrigerant discharged from the compressor 105 passes through the four-way valve 106, enters the outdoor heat exchanger 101, exchanges heat with outdoor air sent by the outdoor fan 103, is condensed, and becomes a liquid refrigerant. Next, the condensed refrigerant passes through the outdoor refrigerant flow control valve 102 that is fully opened, and through the liquid pipe 122, the indoor unit 20.
Sent to 0,300. Further, the liquid refrigerant expands and is decompressed by the indoor refrigerant flow control valve 202, enters the indoor heat exchanger 201, exchanges heat with the indoor air sent by the indoor fan 203, and evaporates. Then, the cooled indoor air is blown from the indoor unit 200 into the room.

Similarly, the refrigerant entering the indoor unit 300 is decompressed by the indoor refrigerant flow control valve 302, enters the indoor heat exchanger 301, and exchanges heat with the indoor air sent by the indoor fan 303 to evaporate. Then, the cooled indoor air is blown out from the indoor unit 300.

The refrigerant flowing out of the indoor unit 200 and the indoor unit 300 joins,
The gas is sent to the outdoor unit 100 through the gas pipe 121. Further, the refrigerant passes through the four-way valve 106, the accumulator 104, and the compressor 105.
, Compressed and discharged again.

Next, a control method during the cooling operation will be described step by step.

(1) The indoor controller 208 determines the cooling capacity Qc2 of the indoor unit 200 as the temperature difference between the intake air temperature and the blown air temperature (t206−
This is calculated from the following equation (1) using t207).

(2) Similarly, the indoor controller 308 determines the cooling capacity of the indoor unit 300.
Qc3 is calculated by the following equation (2) using the temperature difference (t306-t307) between the intake air temperature and the blown air temperature.

(3) The calculated values of the cooling capacities Qc2 and Qc3 are sent to the outdoor controller 151, and the total value QcT of the cooling capacities is obtained as in the following equation (3).

QcT = Qc2 + Qc3 (3) Each symbol is Cp ₂ , Cp ₃ : Specific heat of air SHF2, SHF3: Sensible heat ratio (0.7) t206, t306: Detection values of temperature sensors 206 and 306 t207, t307: Temperature sensor The detection values Va2, Va3 of 207 and 307 are the air volumes ρ ₂ , ρ _{2 of the} indoor units 200 and 300: the density of the air, and the sensible heat ratios SHF2 and SHF3 are 0.7 in this embodiment. Va2 and Va3 are the indoor air flow rates, which can be changed by operating air flow taps of the indoor units.

(4) The indoor controller 208 calculates the intake air temperature of the indoor unit 200.
The difference between t206 and the room temperature set value ts2 (t206−ts2) is second.
The target cooling capacity ratio α2 of the indoor unit 200 is obtained from the relationship shown in the figure, and Qc20 = α2 · Qc200 (4) Qc200: The target cooling capacity Qc20 of the indoor unit 200 is calculated as the rated cooling capacity of the indoor unit 200.

(5) Similarly, the target cooling capacity Qc30 of the indoor unit 300 is calculated as Qc30 = α3 · Qc300 (5) Qc300: Rated cooling capacity of the indoor unit 300.

(6) The values of the target cooling capacity Qc20 and Qc30 are determined by the outdoor controller 151.
The total value QcT0 of the target cooling capacity is obtained as QcT0 = Qc20 + Qc30 (6).

(7) As shown in FIG. 3, the outdoor controller 151 calculates the motor rotation speed of the compressor 105 from the deviation between the total cooling capacity QcT0 of (6) and the total cooling capacity QcT of (3). Is calculated by PID calculation, and the capacity of the compressor is controlled.

(8) On the other hand, as shown in FIG. 4, the cooling capacities Qc2 and Qc3 of the indoor units 200 and 300 are controlled by the indoor refrigerant flow regulating valves 202 and 302 so as to approach the target cooling capacities Qc20 and Qc30.

As described above, as shown in FIG. 2, the difference (t206−ts2) between the intake air temperature and the room temperature set value is (t306−ts3) = 4.
When the temperature is higher than ° C, the target cooling capacity ratios α2 and α3 are 1 respectively, and the target cooling capacity Qc20 and Qc30 of the indoor units 200 and 300 are the rated cooling capacity of the indoor units 200 and 300.

When (t206−ts2) and (t306−ts3) are 4 ° C. or less, the target cooling capacity ratios α2 and α3 are respectively reduced to 1 or less, and the target cooling capacity Qc20 and Qc30 are the rated cooling capacity of the indoor units 200 and 300. The capacity of the indoor units 200 and 300 is controlled as follows.

When (t206−ts2) and (t306−ts3) become equal to or less than 0, the indoor unit is turned off and the target cooling capacity ratio α2,
α3 becomes 0.

Note that the rated cooling capacity changes depending on the pipe length of the gas pipe 121 and the liquid pipe 122. The longer the pipe length, the lower the rated cooling capacity.

 Next, the operation during the heating operation will be described.

Dashed arrows shown in the gas pipe 121 and the liquid pipe 122 indicate the refrigerant flow direction during the heating operation.

The refrigerant discharged from the compressor 105 passes through the four-way valve 106, enters the gas pipe 121, and is sent to the indoor units 200 and 300.
The refrigerant that has entered the indoor unit 200 enters the indoor heat exchanger 201, exchanges heat with the indoor air sent by the indoor fan 203, condenses, and warms the indoor air. Further, the condensed refrigerant exits the indoor unit 200 through the indoor refrigerant flow control valve 202.

Similarly, the refrigerant entering the indoor unit 300 is condensed and exits the indoor unit 300. The refrigerants that have exited the indoor units 200 and 300 join,
The liquid enters the outdoor unit 100 through the liquid pipe 122. Further, the refrigerant is decompressed by the indoor refrigerant flow control valve 102, enters the outdoor heat exchanger 101, exchanges heat with the outdoor air sent by the outdoor fan 103, evaporates, passes through the four-way valve 106, the accumulator 104, and the compressor 105. , Compressed and discharged again.

Next, a control method during the heating operation will be described step by step.

(1) The indoor controller 208 of the indoor unit 200 calculates the heating capacity Qh2 of the indoor unit 200 by the following equation (7) using the temperature difference (t207-t206) between the intake air temperature and the blown air temperature. .

_{Qh2 = Cp 2 · ρ 2 ·} Va2 · (t207-t206) (7) (2) Similarly, the indoor control unit 308 of the indoor unit 300, the indoor unit 30
The heating capacity Qh3 of 0 is calculated by the following equation (8) using the temperature difference (t307-T306) between the intake air temperature and the blown air temperature.

_{Qh3 = Cp 3 · ρ 3 ·} Va3 · (t307-t306) (8) (3) Heating calculated respectively capability Qh2, the value of QH3 is sent to the outdoor controller 151, the total value QhT of heating capacity, It is obtained as in the following equation (9).

QhT = Qh2 + Qh3 (9) (4) The indoor controller 208 calculates the suction air temperature of the indoor unit 200.
The fifth difference is determined by the difference (ts2-t206) between t206 and the room temperature set value ts2.
The target heating capacity ratio β2 of the indoor unit 200 is determined from the relationship shown in the figure, and Qh20 = β2 · Qh200 (10) Qh200: The target heating capacity Qh20 of the indoor unit 200 is calculated as the rated heating capacity of the indoor unit 200.

(5) Similarly, the target heating capacity Qh30 of the indoor unit 300 is calculated as Qh30 = β3 · Qh300 (11) Qh300: Rated heating capacity of the indoor unit 300.

(6) The values of the target heating capacities Qh20 and Qh30 are determined by the outdoor controller 151.
The total value QhT0 of the target heating capacity is obtained as QhT0 = Qh20 + Qh30 (12).

(7) As shown in FIG. 6, the outdoor controller 151 calculates the total value QhT0 of the target heating capacity in (6) and the total value of the heating capacity in (3).
The motor speed of the compressor 105 is obtained by PID calculation from the deviation from QhT, and the capacity of the compressor is controlled.

(8) On the other hand, the heating capacity Qh2 and Qh3 of the indoor units 200 and 300 are the fourth.
As in the case of the cooling shown in the drawing, the indoor refrigerant flow control valves 202 and 302 are controlled so as to approach the target heating capacities Qh20 and Qh30.

The outdoor refrigerant flow control valve 102 is controlled by the outdoor controller 151 so that the discharge temperature of the compressor 105 detected by the discharge temperature detector 115 becomes a set temperature.

Note that the rated heating capacity varies depending on the length of the gas pipe 121 and the liquid pipe 122. The longer the pipe length, the lower the rated heating capacity.

According to the present embodiment, since it is not necessary to control the low pressure and the high pressure, there is no need for each pressure sensor, and there is an effect of cost reduction.

Another embodiment of the present invention is shown in FIG. 7, FIG. 8, and FIG.

FIG. 7 is a block diagram showing a configuration of a refrigeration cycle of a multi-room air conditioner according to another embodiment of the present invention. FIG. 8 is a graph showing the relationship between the operation of the pressure switch with respect to the discharge pressure and the maximum opening of the indoor refrigerant flow control valve. FIG. 9 is a graph showing the relationship between the indoor suction air temperature and the maximum opening of the indoor refrigerant flow control valve.

In the embodiment shown in FIG. 7, pressure switches 107 and 108 are attached to the compressor discharge side of the embodiment shown in FIG. 1, and their signals are input to the outdoor controller 151. The flow and control method of the refrigerant during the cooling operation are the same as in the embodiment of FIG.

Also, the flow and control method of the refrigerant during the heating operation are the same as in the embodiment of FIG. 1, but the maximum opening degree of the indoor refrigerant flow regulating valves 202 and 302 during the heating operation is set to the pressure as shown in FIG. It is changed by the combination of the output signals of the switches 107 and 108.

ON the pressure switch 107 exceeds ^{20kg / cm 2, 20kg / cm} 2
OFF when below the pressure switch 108 exceeds 24 kg / cm ² O
Turn off at N, 24 kg / cm ² or less.

The indoor refrigerant flow regulating valves 202 and 302
When N, the full opening of the indoor refrigerant flow regulating valve is set to the maximum opening, and when the pressure switch 107 is turned off, the full opening x 0.5 is set to the maximum opening.

When the pressure switch 107 is ON and the pressure switch 108 is OFF, the maximum opening is not changed.

Above, O a case of using the HCF22 or R407C the refrigerant, when using R410A or R410B the refrigerant, ON when the pressure switch 107 exceeds 31 kg / cm ^2, at 31 kg / cm ² or less
FF, pressure switch 108 turns on when 35 kg / cm ² is exceeded, 35 kg / cm ²
It is good to set it to be off when cm ² or less.

FIG. 9 shows an example in which the maximum opening degree of the indoor refrigerant flow control valves 202 and 302 is changed by the intake air temperatures t206 and t306 of the respective indoor units, and will be described below.

When the suction air temperature exceeds 30 ° C, the indoor refrigerant flow control valve sets the full opening to the maximum opening, and the suction air temperature becomes 25 ° C.
When the temperature drops below ℃, the full opening x 0.5 is the maximum opening. The maximum opening is not changed when the suction air temperature is over 25 ℃ and below 30 ℃.

By providing the maximum opening with hysteresis as in the present embodiment, hunting of the refrigeration cycle due to frequent opening changes of the indoor refrigerant flow control valve can be prevented.

Another embodiment of the method for controlling the indoor refrigerant flow control valve will be described with reference to FIGS.

FIG. 10 is a plan view showing a component arrangement of a control board of an indoor controller of an indoor unit, and FIG. 11 is a relational diagram showing ON / OFF combinations of dip switches of the control board and operation coefficients.

The basic control method is the same as in Fig. 4, but the method for determining the cooling capacity is as follows. The temperature difference between the intake air temperature and the blown air temperature can be changed by the correction coefficients ac2 and ac3 and the indoor air volume coefficients av2 and av3 as Expressions (13) and (14).

Also, how to obtain the heating capacity also equation (15) and (16) Qh2 = ah2 · Cp 2 · ρ 2 · av2 · Va2 · (t207-t206) (15) Qh3 = ah3 · Cp 3 · ρ 3 · av3 · Va3 · (t307−t306) (16) The temperature difference between the outlet air temperature and the inlet air temperature can be changed by the correction coefficients ah2 and ah3 and the indoor air volume coefficients av2 and av3.

By the above correction, the calculation of the indoor functional force is made more accurate, and the accurate control of the indoor refrigerant flow rate adjustment valve and the compressor capacity can be realized.

Next, a method of changing the sensible heat ratio of the indoor unit 200, each correction coefficient, and the indoor air volume coefficient will be described.

In FIG. 10, a dip switch 211 (D
SW1), 212 (DSW2), 213 (DSW3), 214 (DSW4). One DIP switch is 4 ON
It consists of / OFF switches, and each coefficient can be changed by its combination.

FIG. 11 shows an example of changing the coefficient. The sensible heat ratio is changed based on the atmosphere in which the indoor unit is installed, and the general office room has a value of about 0.7. This value is set small in a place with high humidity such as a kitchen, and is set large in a place with low humidity such as a computer room.

The correction coefficient ac2 is a correction coefficient for the temperature distribution of the blown air temperature of the cooling, and is set to 1.0 when the temperature detected by the temperature detector 207 is the average blown air temperature, and is larger than 1 when the temperature is higher than that. Value. When the detected temperature is lower than the average blown air temperature, a value smaller than 1 is set.

The correction coefficient ah2 is a correction coefficient for the temperature distribution of the outlet air temperature of heating, and is set to 1.0 when the temperature detected by the temperature detector 207 is the average outlet air temperature, and is set when a higher temperature is detected. The value is set to a value smaller than 1. If the detected temperature is lower than the average blown air temperature, a value larger than 1 is set.

Since the indoor controller 208 needs a large storage capacity to store the indoor unit capacity and all the airflows of the indoor models, only the representative airflow is stored and corrected by the indoor airflow coefficient av2.

The indoor air volume coefficient is set to 1.0 when the actual air volume is the same as the stored representative air volume, and is set to a value smaller than 1 when the actual air volume is smaller than the representative air volume and to a value larger than 1 when the actual air volume is larger than the representative air volume.

Still another embodiment of the present invention will be described with reference to FIGS.

FIG. 12 is a block diagram showing a configuration of a refrigeration cycle of a multi-room air conditioner at the time of a heating operation according to another embodiment of the present invention, and FIG. 13 is an outdoor refrigerant flow control valve opening degree and indoor refrigerant flow control. It is a graph showing the relationship between the minimum opening degree of a valve and the opening degree of an indoor refrigerant flow control valve of a stop indoor unit.

FIG. 12 shows a refrigeration cycle when the indoor units 200 and 300 perform a heating operation, and the liquid tank 109 is installed on the gas pipe 121 side. Otherwise, it is the same as the refrigeration cycle of FIG. 1 already described.

During cooling, the inside of the liquid tank 109 is at a low pressure, and the temperature of the refrigerant is lower than the ambient temperature. Therefore, the refrigerant does not condense and remain as a liquid refrigerant.

During heating, the refrigerant becomes a high pressure and the refrigerant temperature becomes higher than the ambient temperature.
Collect in 9. Thereby, the surplus refrigerant at the time of heating can be absorbed.

The pipe for guiding the refrigerant into the liquid tank 109 rises up to the upper part in the liquid tank 109, so that the liquid refrigerant does not return to the accumulator 104 at once even if the four-way valve is switched due to defrosting or the like.

In FIG. 1, the indoor unit 200 is operated at the maximum capacity, and the indoor unit 300 is controlled in capacity and the indoor refrigerant flow regulating valve 3 is controlled.
02 has been squeezed and abilities have been reduced. Therefore, indoor units
A large amount of liquid refrigerant is accumulated in the indoor heat exchanger 301 of the 300.

The opening degree of the outdoor refrigerant flow control valve 102 of the outdoor unit 100 is controlled such that the discharge temperature of the compressor 105 detected by the discharge temperature detector 115 becomes a set value. Here, if the indoor refrigerant flow control valve 302 of the indoor unit 300 is excessively throttled, the liquid refrigerant will collect too much in the indoor heat exchanger 301, and the amount of refrigerant circulating in the refrigeration cycle will decrease. Therefore, the flow rate of refrigerant in the indoor unit 200 decreases, and the heating capacity of the indoor unit 200 becomes insufficient.

When the amount of the refrigerant circulating in the refrigeration cycle decreases, the compressor cannot be cooled, and the discharge temperature increases. Therefore, when the discharge temperature is controlled to be the set value, the opening degree of the outdoor refrigerant flow control valve 102 is increased as the discharge temperature increases. Therefore, as shown in FIG. 13, (1) the opening degree of the outdoor refrigerant flow control valve 102 is equal to the predetermined opening degree A (0.5
X full opening) or less, the indoor refrigerant flow control valves 202, 3
The minimum opening of 02 is (0.1 x full opening).

(2) The opening degree of the outdoor refrigerant flow control valve 102 is equal to the predetermined opening degree B (0.8
X full opening) or more, the indoor refrigerant flow control valves 202 and 3
The minimum opening of 02 is large (0.4 x full opening).

(3) When the opening of the outdoor refrigerant flow regulating valve 102 is between the predetermined opening A and the predetermined opening B, the indoor refrigerant flow regulating valve 20
2. The minimum opening of 302 is from (0.1 × full opening) to (0.4 × full opening) and is a value proportional to the opening of the outdoor refrigerant flow control valve 102.

The minimum opening of the indoor refrigerant flow control valves 202 and 302 is determined by the opening of the outdoor refrigerant flow control valve 102.

As described above, it is possible to prevent the liquid refrigerant from being excessively accumulated in the indoor heat exchanger.

Further, when the indoor unit 300 is stopped, the indoor refrigerant flow control valve 302 is set to a predetermined slightly-opened degree, but also at this time, the liquid refrigerant is in the indoor heat exchanger 301 of the indoor unit 300 in the same manner as described above. If the amount of refrigerant is large and the amount is too large, the amount of refrigerant circulating in the refrigeration cycle decreases, and the heating capacity of the indoor unit 200 becomes insufficient.

Also in this case, the opening degree of the indoor refrigerant flow control valve of the stopped indoor unit is changed by the opening degree of the outdoor refrigerant flow control valve 102 as described above.

That is, as shown in FIG. 13, (1) the opening degree of the outdoor refrigerant flow control valve 102 is equal to the predetermined opening degree A (0.5
(× full opening) or less, the minimum opening of the refrigerant flow regulating valves 202 and 302 of the stopped indoor unit is (0.05 × full opening).

(2) When the opening of the outdoor refrigerant flow regulating valve 102 reaches a predetermined opening C (full opening), the refrigerant flow regulating valve 20 of the indoor stop indoor unit
2. The minimum opening of 302 is large (0.1 x full opening).

(3) When the opening degree of the outdoor refrigerant flow control valve 102 is between the predetermined opening degree A and the predetermined opening degree C, the minimum opening degree of the indoor refrigerant flow control valves 202 and 302 of the indoor stop indoor unit is (0.05). The value ranges from (× full opening) to (0.1 × full opening) and is proportional to the opening of the outdoor refrigerant flow control valve 102.

The minimum opening degree of the indoor refrigerant flow control valves 202 and 302 of the indoor stop indoor unit is determined by the opening degree of the outdoor refrigerant flow control valve 102.

As described above, even when the indoor unit 300 is stopped, the liquid refrigerant can be prevented from being excessively accumulated in the indoor heat exchanger.

According to the present invention, since the capacity of the compressor is controlled such that the capacity of the operated indoor unit becomes the required target capacity, the compressor is operated with power consumption corresponding to the required capacity of the indoor unit, and in particular, heating is performed. A multi-room air conditioner with low power consumption during operation is provided.

Also, particularly during the heating operation, the amount of refrigerant circulating in the refrigeration cycle is secured by changing the degree of opening of the indoor refrigerant flow control valve of the indoor unit according to the degree of opening of the outdoor refrigerant flow control valve, thereby preventing insufficient capacity. A multi-room air conditioner is provided.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-1-127842 (JP, A) JP-A-63-465336 (JP, A) JP-A-6-18075 (JP, A) JP-A-6-18075 50591 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) F24F 11/02 102

Claims (16)

(57) [Claims] An indoor unit provided with a variable capacity compressor and an outdoor heat exchanger is connected to a plurality of indoor units provided with an indoor heat exchanger, an indoor fan, and means for detecting intake air temperature and blown air temperature. In a multi-room air conditioner connected by a pipe and a gas pipe to form a refrigeration cycle, a means for determining a cooling or heating capacity by a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, and the intake air temperature and room temperature Means for determining a target cooling or heating capacity based on a difference from a set value, and controlling the operating capacity of the variable displacement compressor such that the total value of the cooling or heating capacity becomes the total value of the target cooling or heating capacity. A multi-room air conditioner characterized by: 2. An outdoor unit having a variable capacity compressor and an outdoor heat exchanger, a plurality of indoor units having an indoor heat exchanger, an indoor fan, and means for detecting intake air temperature and blown air temperature. In a multi-room air conditioner connected by a pipe and a gas pipe to form a refrigeration cycle, a means for determining a cooling capacity by a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, and the intake air temperature and room temperature set value Means for determining a target cooling capacity based on a difference between the cooling capacity and the operating capacity of the variable capacity compressor so that the total value of the cooling capacity becomes the total value of the target cooling capacity. Air conditioner. 3. An outdoor unit having a variable capacity compressor and an outdoor heat exchanger, a plurality of indoor units having an indoor heat exchanger, an indoor fan, and means for detecting intake air temperature and blown air temperature. In a multi-room air conditioner connected by pipes and gas pipes to form a refrigeration cycle, a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and air Specific heat, means for determining a cooling capacity from the sensible heat ratio, and means for determining a target cooling capacity by the difference between the suction air temperature and the room temperature set value, the sum of the cooling capacity is the sum of the target cooling capacity A multi-room air conditioner, wherein the operation capacity of the variable displacement compressor is controlled so as to be a value. 4. An outdoor unit having a variable capacity compressor and an outdoor heat exchanger, a plurality of indoor units having an indoor heat exchanger, an indoor fan, and means for detecting intake air temperature and blown air temperature. In a multi-room air conditioner connected by pipes and gas pipes to form a refrigeration cycle, a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and air Means for determining a heating capacity from the specific heat, and means for determining a target heating capacity by a difference between the suction air temperature and the room temperature set value, so that a total value of the heating capacity becomes a total value of the target heating capacity. A multi-room air conditioner, wherein an operation capacity of the variable capacity compressor is controlled. 5. An outdoor unit having a variable capacity compressor and an outdoor heat exchanger, a plurality of indoor units each having an indoor heat exchanger, an indoor fan, and means for detecting intake air temperature and blown air temperature. In a multi-room air conditioner connected by piping and gas piping to constitute a refrigeration cycle, a means for determining a cooling capacity by a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, and a room temperature set value from the intake air temperature The difference between 2 and 4
Means for setting the target cooling capacity as the rated cooling capacity of the indoor unit when the cooling capacity is higher than ° C, and setting the target cooling capacity as the rated cooling capacity or less for the indoor unit when the temperature is 2 to 4 ° C or less. Wherein the operating capacity of the variable displacement compressor is controlled so that the total value of the target cooling capacity becomes the total value of the target cooling capacity. 6. An outdoor unit having a variable capacity compressor and an outdoor heat exchanger, a plurality of indoor units having an indoor heat exchanger, an indoor fan, and means for detecting intake air temperature and blown air temperature. In a multi-room air conditioner connected by pipes and gas pipes to form a refrigeration cycle, a means for determining a heating capacity based on a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, and the suction air temperature from a room temperature set value. The difference between 2 and 4
Means for setting the target heating capacity as the rated heating capacity of the indoor unit when the temperature is higher than ° C, and setting the target heating capacity as the rated heating capacity or less for the indoor unit when the temperature is 2 to 4 ° C or lower. Wherein the operating capacity of the variable displacement compressor is controlled so that the total value of the target heating capacity becomes the total value of the target heating capacity. 7. The indoor unit according to claim 3, further comprising an indoor refrigerant flow control valve in the indoor unit, and controlling an opening degree of the indoor refrigerant flow control valve so that the cooling capacity becomes the target cooling capacity. A multi-room air conditioner characterized by the following. 8. The indoor unit according to claim 4, further comprising an indoor refrigerant flow control valve in the indoor unit, and controlling an opening degree of the indoor refrigerant flow control valve so that the heating capacity becomes the target heating capacity. A multi-room air conditioner characterized by the following. 9. An outdoor unit having a variable capacity compressor and an outdoor heat exchanger, comprising a plurality of indoor units including an indoor heat exchanger, an indoor fan, an indoor refrigerant flow control valve, and means for detecting suction air temperature and blown air temperature. In a multi-room air conditioner in which two indoor units are connected by a liquid pipe and a gas pipe to form a refrigeration cycle, a temperature difference between an intake air temperature and an outlet air temperature of the indoor units, an air volume of the indoor units, and air Means for determining the heating capacity from the density of the air and the specific heat of the air; means for determining the target heating capacity by the difference between the suction air temperature and the room temperature set value; and Means for controlling the operating capacity of the variable capacity compressor such that the opening capacity of the indoor refrigerant flow control valve is controlled such that the heating capacity becomes the target heating capacity; and Multi-room air conditioner discharge pressure is characterized in that a means be smaller than the total opening degree of maximum opening of the indoor refrigerant flow regulating valve when the predetermined value or less. 10. An outdoor unit having a variable capacity compressor and an outdoor heat exchanger, a plurality of indoor units each having an indoor heat exchanger, an indoor fan, and means for detecting intake air temperature and blown air temperature. In a multi-room air conditioner connected by pipes and gas pipes to form a refrigeration cycle, a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and air Means for determining a heating capacity from the specific heat; means for determining a target heating capacity based on a difference between the suction air temperature and a room temperature set value; and the variable so that a total value of the heating capacity becomes a total value of the target heating capacity. Means for controlling the operating capacity of the displacement compressor; means for controlling the opening of the indoor refrigerant flow control valve so that the heating capacity becomes the target heating capacity; and And a pressure switch that is turned off when the pressure becomes 20 kg / cm ² or less, wherein the maximum opening of the indoor refrigerant flow regulating valve is (full opening x 0.5) when the pressure switch is turned off. Multi-room air conditioner. 11. An outdoor unit having a variable capacity compressor and an outdoor heat exchanger, a plurality of indoor units each having an indoor heat exchanger, an indoor fan, and means for detecting intake air temperature and blown air temperature. In a multi-room air conditioner connected by pipes and gas pipes to form a refrigeration cycle, a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and air Means for determining a heating capacity from the specific heat; means for determining a target heating capacity based on a difference between the suction air temperature and a room temperature set value; and the variable so that a total value of the heating capacity becomes a total value of the target heating capacity. Means for controlling the operation capacity of the displacement compressor; means for controlling the opening degree of the indoor refrigerant flow control valve so that the heating capacity becomes the target heating capacity; and wherein the suction air temperature is equal to or less than a predetermined value. Multi-room air conditioner which is characterized in that a means be less than fully open opening a maximum opening of the indoor refrigerant flow regulating valve when. 12. An outdoor unit having a variable capacity compressor and an outdoor heat exchanger, a plurality of indoor units each having an indoor heat exchanger, an indoor fan, and means for detecting intake air temperature and blown air temperature. In a multi-room air conditioner connected by pipes and gas pipes to form a refrigeration cycle, a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and air Means for determining a heating capacity from the specific heat; means for determining a target heating capacity based on a difference between the suction air temperature and a room temperature set value; and the variable so that a total value of the heating capacity becomes a total value of the target heating capacity. Means for controlling the operating capacity of the displacement compressor; and means for controlling the opening degree of the indoor refrigerant flow control valve so that the heating capacity becomes the target heating capacity, wherein the suction air temperature is not 20. When the temperature is 25 ° C or less, the maximum opening of the indoor refrigerant flow control valve is (full opening × 0.5)
A multi-room air conditioner characterized by the following. 13. The multi-chamber system according to claim 1, wherein the cooling capacity is obtained by correcting the cooling capacity with a correction coefficient of a temperature distribution of blown air temperature and a indoor air flow coefficient. Air conditioner. 14. The air conditioner according to claim 1, wherein the heating capacity is obtained by correcting the heating capacity with a correction coefficient of a temperature distribution of a blown air temperature and a indoor air volume coefficient. Multi-room air conditioner. 15. An outdoor unit having a variable capacity compressor and an outdoor heat exchanger, a plurality of indoor units having an indoor heat exchanger, an indoor fan, and means for detecting intake air temperature and blown air temperature. In a multi-room air conditioner connected by pipes and gas pipes to form a refrigeration cycle, a temperature difference between an intake air temperature and an outlet air temperature of the indoor unit, an air volume of the indoor unit, an air density, and air Means for determining a heating capacity from the specific heat; means for determining a target heating capacity based on a difference between the suction air temperature and a room temperature set value; and the variable capacity so that a total value of the heating capacity becomes a total value of the target heating capacity. Means for controlling the operating capacity of the compressor, wherein during the heating operation, the opening degree of the indoor refrigerant flow regulating valve of the indoor unit is changed according to the opening degree of the outdoor refrigerant flow regulating valve. Murokora Air conditioner. 16. An outdoor refrigerant flow regulating valve according to claim 15, wherein when the outdoor refrigerant flow regulating valve has an opening of not more than (0.5 × full opening), the minimum opening of the indoor refrigerant flow regulating valve is set to (0.
When the opening of the outdoor refrigerant flow control valve is equal to or more than (0.8 × full opening), the minimum opening of the indoor refrigerant flow control valve is set to (0.
When the opening degree of the outdoor refrigerant flow control valve is between (0.5 x full opening degree) and (0.8 x full opening degree), the minimum opening degree of the indoor refrigerant flow control valve is (0.1 x full opening degree). X full opening) to (0.4 x full opening)
The multi-room air conditioner is characterized in that the value up to is set to a value proportional to the opening of the outdoor refrigerant flow control valve.