JPS63271069A - Multiple chamber type air conditioenr - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Go to 2・ Industrial applications The present invention relates to a multi-chamber air conditioner.

BACKGROUND OF THE INVENTION In recent years, multi-chamber air conditioners using inverter compressors and electric expansion valves have become more common.

In such a refrigeration system, various methods have been proposed to prevent refrigerant from accumulating in the stop unit and the thermo-operation unit during heating operation.

For example, there is a method of interposing electromagnetic valves at the inlet and outlet sides of the indoor heat exchanger, but this increases the cost and complicates the refrigerant circuit, so recently, electric expansion valves have been proposed as in JP-A-61-128069. A method of preventing refrigerant build-up is to slightly open the refrigerant and allow a small amount of high-temperature, high-pressure gas to flow through.

Problems to be Solved by the Invention However, with the method described above, the electric expansion valve is fully closed even in the thermo-operated unit during cooling, completely cutting off the flow of refrigerant, resulting in a rapid increase in the humidity of the blown air. In addition, during heating, the blower of the thermo-operated unit is stopped, and the electric expansion valve is controlled to open slightly in the same way as the stop unit, so that the room temperature suddenly rises. However, it has the disadvantage that the amount of heat radiated to the stop unit, which is a heat loss, is the same as the amount of heat radiated to the thermo-operated unit, which is not a heat loss, resulting in extremely poor efficiency.

The present invention provides a multi-room air conditioner that eliminates the above drawbacks.

Means for Solving the Problems In order to solve the above-mentioned problems, the multi-room air conditioner of the present invention includes a plurality of indoor units each provided with an electric expansion valve, so that the operation unit performs a pressure reducing action during cooling. When closing, the stop unit is fully closed, and the thermo-operation unit is slightly opened. During heating, the operation unit is open, and the stop unit and thermo-operation unit are slightly open, and the opening of the stop unit is set to the opening of the thermo-operation unit. This device is equipped with a control device for an electric expansion valve that makes the air flow smaller than the air flow rate, and a control circuit that forces the blower of the thermo-operated unit to the minimum air volume during heating.

Function The present invention has the above-described configuration, and the electric expansion valve control device controls each electric expansion valve, and during cooling, the operation unit performs a pressure reducing action, and the stop unit fully closes the valve. By stopping the supply of refrigerant to the stop unit, and by slightly opening the thermo-operated unit, it is possible to supply enough refrigerant to prevent a sudden temperature rise in the indoor heat exchanger that serves as the evaporator. .

In addition, during heating, the operation unit is opened, and the opening degree of the stop unit is smaller than the opening degree of the thermo-operation unit.
In addition, by forcing the air blower of the thermo-operated unit to the minimum air volume, the heat loss in the stopped unit can be significantly reduced compared to the amount of heat dissipated in the thermo-operated unit.

Example Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In the figure, an outdoor unit 1 includes a compressor 2, 5 bases on all sides,
7. Consists of a valve 3, an outdoor heat exchanger 4, a heating pressure reducing valve 5, a check valve 6 that bypasses the heating pressure reducing valve 5 during cooling, an accumulator 7, a liquid pipe 8, a gas pipe 9, etc. In addition, the liquid pipe 8 and the gas pipe 9 are a liquid side main pipe 1o and a gas side main pipe 1 which connect indoor and outdoor.
1. Liquid side branch pipes 12 branched by the number of indoor units.
a, 12b.

Indoor units) 14a, 14b connected to the 12C1 gas side branch pipes 13a, 13b, 13C, respectively.

140 are indoor heat exchangers 15a and 15b, respectively.

15C1 gas side branch pipes 13a, 13b, 13c, liquid side branch pipes 12a, 12b, 12c and indoor coil 15a.

Electric expansion valves 17a and 17b are interposed between the expansion valves 15b and 15c, respectively, and have their opening degrees adjusted by the control device 16.

17c, a control circuit 19 and the like is configured to forcibly set the air blowers 18a, 18b, and 18c to the minimum air volume when the room temperature reaches a set temperature during heating.

The operation of the multi-chamber heat pump air conditioner configured as above will be described below. First, it is assumed that only the indoor unit 14a is being operated for cooling. The refrigerant gas discharged from the compressor 2 is condensed and liquefied in the outdoor heat exchanger 4 that passes through the four-way valve 3, passes through the check valve 6, the liquid pipe 8, and the liquid side pipe 10, and then flows into the liquid side branch pipe 1.
2a, the pressure is reduced by the electric expansion valve 17a whose opening degree is adjusted by the control device 16, and the gas is evaporated in the indoor heat exchanger 15a, and then the gas side branch pipe 13a.

The gas side pipe 11, gas pipe 9, four-way valve 3, and accumulator 7 are passed through and returned to the compressor 2. At this time, indoor unino) 14
b, 140 is stopped, electric expansion valve 1-rb, 1
7C is completely closed by the control device 16, and the indoor unit 7)
There is no refrigerant supply to 14b and 14c. or,
When all three indoor units 14a, 14b, and 14c are operated, the electric expansion valve 17b.

1AC has its opening adjusted and is connected from the liquid side pipe 1o to the liquid side branch pipe 12b.
, 12c, and the refrigerant is supplied to the three indoor units.

At this time, for example, if the temperature of the room in which the indoor unit 14a is installed reaches the set temperature, the electric expansion valve 17a is controlled by the control device 16 to open at a slightly opened degree (for example, 1/10 of full open). ), and the supply of cold tofu is continued to the extent that the temperature of the indoor heat exchanger 15a does not rise rapidly.

Next, heating operation will be explained. The refrigerant gas discharged from the compressor 2 passes through the four-way valve 3, the gas pipe 9, and the gas side pipe 11 to reach the gas side branch pipes 13a, 13b, and 13c. Here, assuming that all three indoor units 14a, 14b, and 14c are in operation, the gas side branch pipes 13a, 13
The refrigerant gas divided into b and 13c is transferred to the indoor heat exchanger 15.
It is condensed and liquefied at a, 15b, and 15a. This liquid refrigerant is supplied to the electric expansion valve 17a which is opened by the control device 16,
17b, 1γC, and liquid side branch pipes 12a, 12
b, 12a, the liquid side pipe 10, and the liquid pipe 8, the pressure is reduced by the heating pressure reducing valve 6, evaporated in the outdoor heat exchanger 4, and returns to the compressor 1 via the four-way valve 3 and the accumulator 7.

Next, when the indoor uni-sole l-14a is stopped, the stain-operated expansion valve 17a is closed by the control device 16, but it is not fully closed, but slightly opened (for example, 1/10 of the fully open position). The amount of refrigerant diverted to the gas side branch pipe 13a by this operation is set to a refrigerant flow rate commensurate with the amount of liquid refrigerant that is liquefied by natural heat radiation radiated by the indoor heat exchanger 15a. Next, it is assumed that the temperature of the room in which the indoor Unisol l-14b is installed has reached the set temperature. In other words, when the indoor unit 14a is stopped, the indoor unit 14b is in thermostat mode, and the indoor unit 14C is in operation, the control circuit 18 forces the blower of the indoor unit 14b to the lowest air volume, and the electric expansion valve 14a and 14b are controlled to be slightly open by the control device 16, but at this time, the opening degree of the electric expansion valve 14a is controlled to be smaller than the opening degree of the electric expansion valve 14b (for example, the electric expansion valve 14a is fully open (1710), whereas the electric expansion valve 14b is opened 1/8 of the fully open position.

As described above, according to this embodiment, during cooling, the thermo-operated unit does not fully close the electric expansion valve, but slightly opens it to supply an amount of refrigerant that does not cause the temperature of the indoor heat exchanger to rise rapidly. This prevents a sudden increase in humidity in the blown air.
Comfortable cooling operation can continue.

In addition, during heating, a control circuit is provided to set the blower of the thermo-operated unit to the minimum air volume, and the control device controls the opening degree of the electric expansion valve of the thermo-operated unit and the electric expansion valve of the thermo-operated unit. By controlling the opening to be smaller than the opening of the thermostat, it is possible to prevent a sudden drop in room temperature during thermostat operation, and the heat loss radiated by the stop unit is extremely small compared to the amount of heat radiated by the thermostat unit, resulting in high efficiency. Heating operation can be continued.

Effects of the Invention As described above, the present invention provides electric expansion valves for each of a plurality of indoor units, performs a pressure reducing action in the cooling operating unit, fully closes the shut-off unit, and slightly opens the thermostat operating unit, and provides heating. An electric expansion valve control device that opens the operating unit at times, slightly opens the stop unit and thermo-operation unit, and makes the opening degree of the stop unit smaller than the opening degree of the thermo-operation unit; and Equipped with a control circuit that forces the air blower of the operation unit to the minimum air volume, the thermo-operation unit can prevent a sudden increase in humidity when air is blown out during cooling, and can prevent the installation of the thermo-operation unit during heating. It is possible to prevent the room temperature in the room in which the heater is placed from dropping, and to reduce heat loss to the shutdown unit, allowing efficient heating operation to continue.

[Brief explanation of drawings]

The figure is a refrigeration cycle diagram of a multi-chamber heat pump type air conditioner showing one embodiment of the present invention. 1...Outdoor unit, 2...Compressor, 4
・・・・・・Outdoor heat exchanger, 14a, 14b, 14c・
...Indoor unit, 15a, 15b, 15c...
...Indoor heat exchanger, 16...Control device, 1
7a, 17b, 17c...Electric expansion valve, 18a,
18b, 18c...Blower, 19...Control circuit.

Claims (1)

[Claims] One outdoor unit with a compressor and an outdoor heat exchanger,
A plurality of indoor units connected to the outdoor unit and each having an electric expansion valve indoor heat exchanger and an indoor unit (hereinafter referred to as an operating unit) which controls the electric expansion valve and operates during cooling, performs a depressurization action. The indoor unit to be closed and stopped (hereinafter referred to as the "stop unit") is fully closed, and the indoor unit (hereinafter referred to as the thermo-operated unit) is opened slightly when the room temperature has reached the set temperature, and during heating, the operation unit is opened and stopped. An electric expansion valve control device that allows the unit and the thermo-operation unit to open slightly and the opening degree of the stop unit to be smaller than the opening degree of the thermo-operation unit, and a control device that forcibly opens the blower of the thermo-operation unit during heating. A multi-room air conditioner characterized by being equipped with a control circuit that provides a minimum air volume.