JPH08313097A - Air conditioner - Google Patents

Abstract

(57) [Summary] [Structure] In an air conditioner that constitutes two independent cooling and refrigeration cycles, one refrigeration cycle system
As a compressor, a compressor with a variable capacity by changing the compressor input frequency by an inverter and a four-way valve for changing the refrigerant flow direction for switching cooling operation and heating operation are provided, and as a compressor of other refrigeration cycle system, commercial A constant capacity compressor driven by a power supply was provided. [Effect] It is possible to realize an operation cycle capable of cooling and heating while reducing the operating cost of the air conditioner by saving space in the indoor unit and reducing the power of the blower.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an air conditioner.

[0002]

2. Description of the Related Art As described in Japanese Patent Laid-Open No. 63-271070, a conventional device heats air after cooling it for dehumidification. For that purpose, a heating operation is performed in a refrigeration cycle. A heat exchanger is provided.

[0003]

In the above-mentioned prior art, it is necessary to provide a heat exchanger dedicated to the heating operation in the indoor unit, and there is a problem that an installation space for that is required, and there are two types of air-conditioned air. There is a problem that the power for the blower increases because the blow resistance increases as it passes through the heat exchanger.

An object of the present invention is to provide an operation cycle capable of cooling and heating, which saves the space in the indoor unit and reduces the operation cost of the air conditioner by reducing the power of the blower.

[0005]

In order to achieve the above object, the present invention is an air conditioner which constitutes two independent cooling / refrigerating cycles. In one refrigerating cycle system, an inverter is used as a compressor. A compressor with a variable capacity and a four-way valve to change the refrigerant flow direction for switching between cooling operation and heating operation by changing the machine input frequency are installed. A capacity compressor was provided.

Further, in the air conditioner, a part of the heat exchanger of the outdoor unit on the side of the refrigeration cycle system on the side on which the variable capacity compressor is installed is provided on the side of the refrigeration cycle system on the side on which the constant capacity compressor is installed. An auxiliary heat exchanger for condensation and a solenoid valve were provided.

Further, when the air conditioner is started when the indoor air temperature is lower than a predetermined temperature, the refrigerating cycle system side on which the variable capacity compressor is installed is first operated by heating operation, and then the indoor load is applied. When the temperature rises and the room air temperature rises above a predetermined temperature, the four-way valve is switched to switch from the heating operation to the cooling operation.

[0008]

As described above, when the indoor load is reduced and the dehumidifying operation is performed, the refrigeration cycle system on the side having the constant capacity compressor is cooled, while the refrigeration cycle system on the side having the variable capacity compressor is operated in four directions. Heating operation is performed with the valve in the direction of refrigerant flow opposite to the cooling operation, the heating capacity is changed by changing the compressor capacity with the inverter, and the cooling capacity is adjusted comprehensively by changing the heating capacity with respect to the cooling capacity. be able to.

Further, it is a part of the heat exchanger of the outdoor unit on the side where the solenoid valve is opened from the refrigeration cycle system on the cooling operation side to heat a part of the high temperature refrigerant at the time of the decrease of the outdoor temperature in winter. Continuing the heating operation by flowing it to the auxiliary heat exchanger for condensation to raise the ambient temperature and the temperature of the heat exchanger itself of the outdoor unit and not frosting the outdoor unit heat exchanger on the heating operation side. You can

When the room air temperature is lower than the predetermined temperature, the heating operation causes the room air temperature to rise, and the room air temperature becomes appropriate for the indoor load to rise. After that, when the indoor load rises and the indoor air temperature rises above a predetermined temperature, the four-way valve is switched and the refrigerant flow direction is reversed to switch from the heating operation to the cooling operation and the cooling operation corresponding to the indoor load. Is possible.

[0011]

Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 is a refrigeration cycle system diagram of the air conditioners of the first and third embodiments, and FIG. 2 is a refrigeration cycle system diagram of the air conditioners of the second and third embodiments.

(First Embodiment) As shown in FIG. 1, the air conditioner in this embodiment is of a remote capacitor type, and the indoor unit is a compressor 1 and a commercial power source whose capacity is variable by changing the compressor input frequency by an inverter. It is composed of main components such as a compressor of constant capacity 2, expansion valves 3 and 4, heat exchangers 5 and 6, accumulators 7 and 8, and stop valves 9, 10, 11, and 12, which are driven by A four-way valve 13, an inverter unit 14 for driving the compressor 1, and a control unit 15 are provided, and the outdoor unit includes heat exchangers 16 and 17 and blocking valves 18 and 1.
It is composed of 9, 20, and 21 main parts, and is connected by independent two-system pipes.

During normal cooling operation, the refrigerant discharged from the compressor 1 is sent to the heat exchanger 17 of the outdoor unit via the four-way valve 13 and the blocking valves 9 and 18 to be condensed, and the blocking valves 20, 11 and After entering the heat exchanger 5 through the expansion valve 3 and evaporating, the four-way valve 1 again
A refrigeration cycle that returns to the compressor 1 via the accumulator 7 via 3 is configured. Further, the refrigerant discharged from the compressor 2 is sent to the heat exchanger 16 of the outdoor unit via the blocking valves 10 and 19 to be condensed, and enters the heat exchanger 6 via the blocking valves 21 and 12 and the expansion valve 4. A cooling and refrigerating cycle that evaporates and returns to the compressor 2 via the accumulator 8. With the above configuration, the control unit 15 operates the two compressors 1 and 2 according to the air conditioning load, or the operation in which the capacity of the compressor 1 is changed by the inverter unit 14 in addition to the compressor 2, the compressor 2 The cooling capacity is changed by selecting only the operation and the operation in which only the compressor 1 is changed in capacity by the inverter unit 14. In the present embodiment, when the control unit 15 determines that the indoor load is less than or equal to the inverter capacity control lower limit of the compressor 1, or when it is determined that only dehumidification should be performed without changing the temperature,
The refrigeration cycle on the compressor 2 side is cooled and the four-way valve 13 of the refrigeration cycle on the compressor 1 side is switched. This allows
The refrigerant discharged from the compressor 1 is sent to the heat exchanger 5 of the indoor unit via the four-way valve 13 to be condensed, and the expansion valve 3 and the blocking valve 1
After passing through 1 and 20, enter the heat exchanger 17 of the outdoor unit and evaporate,
The heating operation of returning from the accumulator 7 to the compressor 1 via the four-way valve 13 again via the stop valves 18 and 9 is performed. Moreover, by controlling the capacity of the inverter unit 14 to change the heating capacity, the intake air of the air conditioner is cooled and heated at the same time, and the heating capacity with respect to the cooling capacity is increased / decreased by the inverter control. The temperature is adjusted to. As described above, it is possible to obtain the cooling capacity in the range below the inverter capacity control lower limit of the compressor 1 from the state where only dehumidification is performed without changing the temperature.

(Second Embodiment) As shown in FIG. 2, this embodiment is a remote condenser type air conditioner similar to the first embodiment and has the same basic construction. In the present embodiment, the auxiliary heat exchanger 23 is installed integrally with the heat exchanger 17 of the outdoor unit of the refrigeration cycle on the compressor 1 side, and the electromagnetic valve 22 is opened to increase the high temperature and high pressure on the compressor 2 side. Refrigerant gas can be supplied. Here, when the air conditioner is performing the refrigeration cycle operation shown in the first embodiment, the compressor 1
Since the heat exchanger 17 of the outdoor unit of the side refrigeration cycle acts as an evaporator, there is a possibility of frost formation when the outside air temperature decreases in winter. Therefore, when the outside air temperature decreases and the evaporation temperature on the compressor 1 side decreases, or when the refrigerant suction pressure of the compressor 1 decreases and frost formation is expected, the solenoid valve 22 is opened. The high-temperature, high-pressure refrigerant gas on the compressor 2 side is supplied to the auxiliary heat exchanger 23 to raise the ambient temperature of the heat exchanger 17 on the compressor 1 side and the temperature of the heat exchange fins to prevent frost formation. As described above, the refrigeration cycle operation shown in the first embodiment can be continuously performed.

(Third Embodiment) This embodiment is a remote condenser type air conditioner similar to the first and second embodiments and has the same basic construction. In this embodiment, the control unit 15
At the time of starting the air conditioner, when the indoor air temperature is lower than the predetermined temperature input to the controller 15 in advance, the four-way valve 13 is switched to the heating operation side and the heat exchanger 5 of the indoor unit acts as a condenser. Heating operation. This allows
The indoor air temperature gradually rises and reaches a temperature within the operable range of an indoor load such as a computer. Here, when an indoor load such as a computer is started, the indoor air temperature further rises due to the heat generated by the equipment, and when the indoor air temperature becomes higher than the predetermined temperature input to the controller 15 in advance, the controller 15 Determines that cooling is necessary, switches the four-way valve 13 to the cooling operation side and causes the heat exchanger 5 of the indoor unit to act as an evaporator to perform the cooling operation. As described above, even when the indoor air temperature is within the operable range of the indoor load of the computer or the like, the indoor temperature condition can be adjusted by the heating operation, and the indoor load of the computer or the like can be started up. In addition, after the indoor load rises, the indoor load can be handled as it is by switching to the cooling operation.

[0017]

According to the present invention, it is possible to realize an operation cycle capable of cooling and heating while reducing the operation cost of the air conditioner by saving the space in the indoor unit and reducing the power of the blower.

[Brief description of drawings]

FIG. 1 is a system diagram of a refrigeration cycle of an air conditioner according to first and third embodiments.

FIG. 2 is a system diagram of a refrigeration cycle of the air conditioners of the second and third embodiments.

[Explanation of symbols]

1, 2 ... Compressor, 3, 4 ... Expansion valve, 5, 6 ... Heat exchanger,
7, 8 ... Accumulator, 9, 10, 11, 12 ... Blocking valve, 13 ... Four-way valve, 14 ... Inverter section, 15 ... Control section, 16, 17 ... Heat exchanger, 18, 19, 20, 21, ...
Stop valve.

Claims (1)

[Claims] Claims: 1. An indoor unit equipped with two compressors, a heat exchanger, and a pressure reducing device, and an outdoor unit equipped with two heat exchangers are connected by two sets of refrigerant pipes to provide two independent systems. In an air conditioner that constitutes a cooling / refrigeration cycle, one cooling / refrigeration cycle system has a compressor with a variable capacity by changing the compressor input frequency by an inverter as a compressor, and a refrigerant flow direction for switching cooling operation and heating operation. A four-way valve for changing is installed, a compressor with a constant capacity that is driven by a commercial power source is installed as a compressor for other cooling and refrigerating cycle systems, and a compressor with a constant capacity is installed when the indoor load decreases and during dehumidification operation. The cooling / refrigerating cycle system on the open side is cooled, and the cooling / refrigerating cycle system on the side on which the variable capacity compressor is installed is set in the direction opposite to the cooling operation by the four-way valve. Performs heating operation Te, the inverter by changing the heating capacity by changing the capacity of the compressor, an air conditioning apparatus characterized by adjusting the overall cooling capability by a change in heating capacity for cooling capacity.