JPH10197028A - Air conditioner - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To set a room temperature and a room humidity within a target value range with a simple and inexpensive configuration and with energy saving. SOLUTION: In a cooling / heating operation, a heat pump refrigeration cycle shown in the drawing is formed to flow a refrigerant in a solid line / dotted arrow direction, depressurize an outdoor flow control valve 5, and fully open an indoor flow control valve 42. During the dehumidifying operation, when the indoor humidity is below the target range, the capacity of the compressor 1 and the outdoor blower 12 is reduced, and the indoor blower is changed according to the relationship between the indoor temperature and the temperature of the second indoor heat exchanger as an evaporator. Thirteen capabilities are controlled. When the indoor humidity is equal to or higher than the target range, dehumidification is promoted by opening the outdoor flow control valve 5 and closing the indoor flow control valve 42, and when the outdoor flow control valve 5 does not enter the target range even when fully opened. The capacity of the compressor 1 and the outdoor blower 12 is increased, and the capacity of the indoor blower 13 is controlled according to the relationship between the indoor temperature and the temperature of the second indoor heat exchanger.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an air conditioner that can set temperature and humidity to target conditions.

[0002]

2. Description of the Related Art As an air conditioner capable of controlling temperature and humidity, an operation capable of performing dehumidification of temperature, dehumidification of constant temperature and dehumidification of temperature by heating a refrigerant and operation of cooling and heating of a room are performed. For example, for example, Japanese Patent Publication No. 4-32
No. 666, which will be described with reference to FIG. 1 is a variable capacity compressor, 2 is a four-way valve, 3 is an outdoor heat exchanger, 4 is a check valve, 5 is a first decompressor (for example, an electric expansion valve), 7 is a check valve, 8 is a two-way valve, 9 is a refrigerant heater, 10 is a gas burner, 11 is a proportional valve, 41 is a first indoor heat exchanger, 42 is a second decompressor (for example, an electric expansion valve), and 43 is a two-way valve. The direction valve 44 is a second indoor heat exchanger.

In FIG. 1, a compressor 1 having variable capacity, a four-way valve 2, an outdoor heat exchanger 3, a check valve 4, a first pressure reducer 5, a first indoor heat exchanger 41, and a second pressure reducer. 42, the second indoor heat exchanger 44, the four-way valve 2, and the check valve 7 are sequentially connected to form a heat pump refrigeration cycle. Further, an electromagnetic two-way valve 43 is connected in parallel to the second decompressor 42, and further, a connection between the check valve 4 and the first decompressor 5 and the suction port of the compressor 1. An electromagnetic two-way valve 8 and a refrigerant heater 9 are sequentially connected therebetween. The refrigerant heater 9 is provided with a gas burner 10 attached thereto.
0 is connected to a combustion supply source (not shown) via a proportional valve 11.

[0004] With the heat pump type refrigeration cycle having such a configuration, the compressor 1 is operated, the four-way valve 2 is inactivated, the electric first decompressor 5 is set in an appropriate throttle state, and the two-way valve 8 is operated. Is closed, the refrigerant heater 9 is stopped (the gas burner 10 is extinguished), the second decompressor 42 is fully opened, and the two-way valve 43 is opened. The refrigerant discharged from 1 is supplied to the four-way valve 2, the outdoor heat exchanger 3, the check valve 4, the first decompressor 5, the first
Operation control means for executing the cooling operation by flowing the indoor heat exchanger 41, the two-way valve 43, the second indoor heat exchanger 44, the four-way valve 2 and the check valve 7 in this order.

[0005] The compressor 1 is operated, and the four-way valve 2 is operated.
In the operating state, the first decompressor 5 is properly throttled, the two-way valve 8 is opened, the refrigerant heater 9 is operated (combustion of the gas burner 10), and the second decompressor 42 is fully opened. By performing control to set the two-way valve 43 to the open state, the refrigerant discharged from the compressor 1 is supplied to the four-way valve 2, the second indoor heat exchanger 44, the two-way valve 43, and the first indoor heat. There is also provided operation control means for causing the exchanger 41, the first decompressor 5, the two-way valve 8, and the refrigerant heater 9 to flow in this order to perform a heating operation.

Further, the compressor 1 is set in an operation state having a capacity lower than the rated value in the cooling operation, the four-way valve 2 is inactivated, the first decompressor 5 is set in a predetermined throttle state, and the two-way valve is set. 8 is closed, the refrigerant heater 9 is stopped, and the second
Is controlled to set the decompressor 42 to the fully open state and the two-way valve 43 to the open state, thereby allowing the refrigerant discharged from the compressor 1 to flow through the four-way valve 2, the outdoor heat exchanger 3, the check valve 4, 1
Operation control means for executing the temperature decreasing dehumidifying operation by flowing in the order of the pressure reducing device 5, the first indoor heat exchanger 41, the two-way valve 43, the second indoor heat exchanger 44, the four-way valve 2 and the check valve 7. Also have.

Further, the compressor 1 is operated, the four-way valve 2 is operated, the first decompressor 5 is fully opened, the two-way valve 8 is opened, and the refrigerant heater 9 is stopped. By controlling the second decompressor 42 to a predetermined throttle state and setting the two-way valve 43 to a closed state, the refrigerant discharged from the compressor 1 is controlled by the four-way valve 2 and the second indoor heat exchange. Unit 44, second decompressor 42, first indoor heat exchanger 4
There is also provided operation control means for executing the constant temperature dehumidification operation by flowing in the order of 1, the first decompressor 5, the two-way valve 8 and the refrigerant heater 9.

Further, the compressor 1 is operated, the four-way valve 2 is operated, the first pressure reducer 5 is fully opened, the two-way valve 8 is opened, and the refrigerant heater 9 is operated. By controlling the second decompressor 42 to a predetermined throttle state and setting the two-way valve 43 to a closed state, the refrigerant discharged from the compressor 1 is controlled by the four-way valve 2 and the second indoor heat exchange. Unit 44, two-way valve 43, first indoor heat exchanger 41, first
There is also provided operation control means for executing the temperature rise dehumidification operation by flowing in the order of the pressure reducer 5, the two-way valve 8 and the refrigerant heater 9 in this order.

[0009]

However, the conventional air conditioner requires a gas burner 10 and a refrigerant heater 9 and thus has a problem that the cost is increased.

If the gas burner 10 is not used, there is no means for operating the indoor heat exchanger with a small capacity and at a low temperature, so that there is a problem that the indoor temperature cannot be sufficiently lowered with a small amount of energy. .

An object of the present invention is to provide an air conditioner which can solve the above problems, suppress the increase in size and increase the cost, and obtain the desired comfortable temperature and humidity conditions with less energy. To provide.

[0012]

In order to achieve the above object, the present invention provides an outdoor heat exchanger having a variable capacity compressor, a variable air flow rate outdoor blower, an outdoor flow control valve, and a first indoor heat control. An indoor temperature sensor, an indoor humidity sensor, and a heat exchange temperature sensor of the second indoor heat exchanger are provided in a refrigeration cycle including an exchanger, an indoor flow rate adjustment valve, and a second indoor heat exchanger including a variable air volume indoor blower. In the dehumidifying operation, when the detected indoor humidity is below the target value range, the capacity of the compressor and the outdoor blower is changed and the second indoor heat exchange as an evaporator is performed. The cooling power and the dehumidifying power are controlled by changing the capacity of the indoor blower according to the temperature detected by the chamber, and when the detected indoor humidity is equal to or more than a target value range, the outdoor flow rate regulating valve and the outdoor flow rate adjusting valve are controlled. Controlling the opening of the indoor flow control valve, When the inner flow control valve was fully open,
By changing the capacity of the indoor blower according to the detected temperature of the second indoor heat exchanger as an evaporator,
Controls cooling and dehumidifying power.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a refrigeration cycle in one embodiment of an air conditioner according to the present invention, wherein A is an outdoor unit and B is an indoor unit, and the portions corresponding to FIG. The description of the operation will be omitted.

In FIG. 1, a four-way valve 2, an outdoor heat exchanger 3, an outdoor flow control valve 5 as a first pressure reducing device 5, a first indoor heat exchanger 41, and a second An indoor flow rate regulating valve 42 as a decompressor and a second indoor heat exchanger 44 are connected, and the outdoor blower 12 having a variable air flow to the outdoor heat exchanger 3 and the indoor blower having a variable air flow to the second indoor heat exchanger 44. 13 are provided, respectively, to constitute a heat pump refrigeration cycle.

The outdoor unit A comprises a compressor 1, a four-way valve 2, an outdoor heat exchanger 3, an outdoor blower 12, and an outdoor flow control valve 5, and the indoor unit B comprises a first unit.
, An indoor heat exchanger 41, an indoor flow rate adjusting valve 42, a second indoor heat exchanger 44, and the indoor blower 13.

FIG. 2 is a block diagram showing a specific example of a control system according to this embodiment. 50 is an indoor control unit, 51 is an indoor control unit, 52 is an indoor temperature sensor, 53 is an indoor humidity sensor, and 54 is an indoor control unit. A temperature sensor (heat exchange temperature sensor) for detecting the temperature of the second indoor heat exchanger 44, 13M is a fan motor (indoor fan motor) of the indoor blower 13, 60 is an outdoor control unit, 61 is an inverter circuit, and 12M is an outdoor. This is a fan motor (outdoor fan motor) of the blower 12, and portions corresponding to FIG. 1 are denoted by the same reference numerals.

In FIG. 1, an indoor control unit 50 is provided in an indoor unit B and includes a microcomputer and its peripheral circuits. This indoor control unit 5
0, an indoor control unit 51, an indoor temperature sensor 52, an indoor humidity sensor 53, a heat exchange temperature sensor 54 of the second indoor heat exchanger 44, an indoor fan motor 13M, and an outdoor flow control valve 5 are connected. Here, the indoor control unit 51
Are used to set operation conditions, start operation, stop operation, and the like.

The outdoor control section 60 is provided in the outdoor unit A, and comprises a microcomputer and its peripheral circuits. An inverter circuit 61, a four-way valve 2, an outdoor fan motor 12M,
The indoor flow control valve 42 is connected. Here, the inverter circuit 61 rectifies the voltage of the commercial power supply, converts it to a predetermined frequency by switching, and supplies it to the compressor 1 as drive power.

Next, the operation state of this embodiment will be described.

In FIG. 1, during the cooling operation, the refrigerant flows as shown by the solid line. That is, the refrigerant discharged from the compressor 1 is supplied to the four-way valve 2, the outdoor heat exchanger 3, the outdoor flow control valve 5, the first indoor heat exchanger 41, the indoor flow control valve 42, and the second indoor heat exchanger. 44, during which the pressure is reduced by the outdoor flow control valve 5, and the indoor flow control valve 42 is set to a fully open state so that a refrigerant pressure difference does not occur before and after the indoor flow control valve 42. Driving is being done.

During the heating operation, the refrigerant flows in the direction opposite to that during the cooling operation, that is, in the direction indicated by the dotted line. At this time, the indoor flow control valve 42 is set to a fully open state so that a refrigerant pressure difference does not occur before and after the indoor flow control valve 42.
The operation is performed such that the pressure of the refrigerant is reduced.

FIG. 3 is a flow chart showing the control operation in each operation of this embodiment.
If the room temperature detected by the room temperature sensor 52 is not within the range of the target value, a series of operations consisting of steps 70 and 71 are repeated, and the rotation speed of the compressor 1 is changed so that the room temperature falls within the range of the target value. Inside.

In the dehumidifying operation for keeping the room humidity within the range of the target value in this embodiment, the refrigerant flows as shown by the solid line in FIG. 1 similar to the cooling operation. Hereinafter, the control of the dehumidifying operation will be described with reference to FIG.

In the initial stage of the dehumidifying operation, since neither the room temperature nor the room humidity is within the range of the target values, step 7
A cooling operation by 0, 71 is performed. Thereafter, when the room temperature detected by the room temperature sensor 52 falls within the range of the target value (step 70), next, it is determined whether or not the room humidity detected by the room humidity sensor 53 is within the range of the target value. A determination is made (step 72).

At this time, assuming that the indoor humidity is higher than the target value range (step 73), the outdoor flow rate is set to lower the temperature of the second indoor heat exchanger 44 so as to obtain a higher humidity. Control is performed in a direction to open the regulating valve and close the indoor flow regulating valve 42 (step 74). In the control of step 74, the cooling power decreases and the dehumidifying power increases. This means that the first indoor heat exchanger 41 is converted from an evaporator to a condenser, and the second indoor heat exchanger 44
This is because, as the evaporator for the first indoor heat exchanger 41, it is necessary to evaporate the refrigerant, so that the temperature of the second indoor heat exchanger 44 decreases and the dew point temperature decreases.
Thereby, the indoor humidity also decreases. Then, the state further proceeds, the outdoor flow control valve 5 is fully opened (step 75), the first indoor heat exchanger 41 functions as a condenser, and the pressure is reduced by the indoor flow control valve 42, and the second indoor heat When the indoor humidity does not fall within the range of the target value even when the exchanger 44 functions as an evaporator, the rotational speed of the compressor 1 is increased to increase the capacity of the compressor 1 (step 76). Is increased (step 77) to increase the humidity.

On the other hand, in the indoor air-conditioning operation, the occurrence of ticks and mold is reduced, and the indoor humidity 60
When the relationship between the room temperature and the latent heat ratio (latent heat amount / total heat amount) was examined when the percentage was set to%, the result shown in FIG. 4 was obtained. According to this, the room temperature is between 15 ° C and 30 ° C.
As shown by the black circles, when the temperature of the evaporator was (room temperature-15 ° C), the latent heat ratio was high, and it was found that latent heat capable of dehumidifying well without frosting on the heat exchanger was obtained. From this, the dehumidifying operation is performed by controlling the rotation speed of the indoor blower 13 and changing the indoor air flow so that the temperature of the evaporator, that is, the second indoor heat exchanger becomes (room temperature −15 ° C.). It can be seen that performing the process has a large amount of latent heat and is efficient.

Therefore, when the temperature of the second indoor heat exchanger is higher than (room temperature-15 ° C) based on the detected temperatures of the indoor temperature sensor 52 and the heat exchange temperature sensor 54 (step 7).
8), reduce the number of revolutions of the indoor blower 13 to reduce its capacity (step 79), and when the temperature of the second indoor heat exchanger is lower than (room temperature-15 ° C) (step 7)
8), The rotational speed of the indoor blower 13 is increased to increase the capacity (step 80).

On the other hand, when the indoor humidity falls below the target value range (step 73), the capacity of the compressor 1 is reduced (step 81), and the air volume of the outdoor blower 12 is reduced (step 82). To reduce the ability to take Thereafter, similarly to the above, when the temperature of the second indoor heat exchanger 44 as the evaporator is higher than (room temperature -15 ° C.) so that dehumidification can be performed efficiently (step 83), The capacity of the indoor blower 13 is reduced (step 85), and when the temperature of the second indoor heat exchanger is lower than (room temperature-15 ° C) (step 83), the capacity of the indoor blower 13 is increased (step 8).
4).

By performing such a series of operations, the room temperature and humidity can be brought within the target value range with the minimum input energy. Further, the refrigerant heater 9 such as the conventional air conditioner shown in FIG. 5, and further, the gas burner 10, the proportional valve 10, the two-way valve 8 and the like become unnecessary, and the configuration is greatly simplified, The size is also greatly reduced.

[0030]

As described above, according to the present invention,
The cooling capacity (sensible heat) and the dehumidifying capacity (latent heat) of the air conditioner can be improved by changing the capacity of the compressor, outdoor blower, and indoor blower, and by changing the first and second decompressors. The temperature and humidity in the room can be adjusted within the range of the target value with the minimum energy. In the conventional air conditioner, the dehumidifying operation at the evaporator temperature where the latent heat ratio is sufficiently large as shown in FIG. 4 has not been performed. I was Since the present invention eliminates such useless operation, it has become possible to operate with nearly half the energy of the conventional case.

[Brief description of the drawings]

FIG. 1 is a diagram showing a refrigeration cycle of an embodiment of an air conditioner according to the present invention.

FIG. 2 is a block diagram showing a control circuit of an embodiment of the air conditioner having the refrigeration cycle shown in FIG. 1 according to the present invention.

FIG. 3 is a flowchart showing operation control of the embodiment shown in FIGS. 1 and 2;

FIG. 4 is a characteristic diagram showing a relationship between an evaporator temperature and a latent heat ratio in the air conditioner.

FIG. 5 is a diagram illustrating an example of a refrigeration cycle of a conventional air conditioner.

[Explanation of symbols]

 Reference Signs List 1 compressor with variable capacity 2 four-way valve 3 outdoor heat exchanger 5 outdoor flow control valve 12 outdoor blower with variable air flow 13 indoor blower with variable air flow 41 first indoor heat exchanger 42 indoor flow control valve 44 second indoor heat Exchanger A Outdoor unit B Indoor unit

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuri Yokozuka 800 Tomita, Ohira-machi, Shimotsuga-gun, Tochigi Prefecture, Hitachi, Ltd. (Hitachi Co., Ltd.) Inside the Machinery Research Laboratory

Claims (1)

[Claims] 1. An outdoor heat exchanger including a variable capacity compressor, a variable air flow outdoor blower, an outdoor flow control valve, a first indoor heat exchanger, a indoor flow control valve, and a second air flow variable indoor blower. A first temperature sensor for sensing indoor temperature, a humidity sensor for sensing indoor humidity, and a second sensor for sensing the temperature of the second indoor heat exchanger are provided in a refrigeration cycle including an indoor heat exchanger.
When the room temperature sensed by the first temperature sensor is within the range of the target value and the room humidity sensed by the humidity sensor is equal to or lower than the lower limit of the range of the target value, The first indoor heat exchanger is operated as a condenser and the second indoor heat exchanger is operated as an evaporator, and the performances of the variable capacity compressor and the outdoor blower are changed. A first control means for performing a dehumidifying operation by changing a capacity of the air volume variable indoor side blower in accordance with a temperature of the second indoor heat exchanger detected by the second temperature sensor; When the room temperature sensed by the temperature sensor is within the range of the target value and the room humidity sensed by the humidity sensor is equal to or more than the upper limit of the range of the target value, the first indoor heat exchanger is used as a condenser, The second indoor heat exchanger is used as an evaporator. A second control means for performing a dehumidifying operation by operating and adjusting the outdoor flow rate control valve and the indoor flow rate control valve; and the indoor flow rate control valve under the control of the second control means. Is fully opened, the capacity of the variable capacity compressor and the outdoor blower is changed, and the indoor side heat exchanger senses the temperature of the second indoor heat exchanger. An air conditioner comprising: third control means for performing a dehumidifying operation by changing a capacity of a blower.