JPH11325672A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner with less danger wherein leakage of a refrigerant is stopped in a part even in the case the leakage of the refrigerant should occur from an indoor unit in an air conditioner which uses combustible refrigerant. SOLUTION: In an air conditioner wherein an outdoor unit 1 provided with a compressor 2, an outdoor heat exchanger 4, and an expansion mechanism and an indoor unit 7 provided with an indoor heat exchanger 8 are connected in order by a piping, and combustible refrigerant is filled, an opening/closing valve 6 is provided on the discharge side of the compressor 2 in the outdoor unit 1, the expansion mechanism is made an electronic expansion valve 5, a gas detector is provided for detecting leakage of the combustible refrigerant inside a room, and opening and closing of the opening/closing valve 5 and the electronic expansion valve 6 are controlled by the gas detector.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner, and more particularly, to a structure of an air conditioner using a flammable refrigerant which can cope with refrigerant leakage.

[0002]

2. Description of the Related Art As shown in a refrigerant circuit diagram of FIG. 6, a conventional air conditioner has an outdoor unit 1 installed outdoors. The outdoor unit 1 has a compressor 2 for compressing refrigerant vapor, It comprises an outdoor heat exchanger 4 for exchanging heat of the refrigerant with the outside air, and an electronic expansion valve 5 which is an expansion mechanism through which the refrigerant passes and adiabatically expands. 7 is an indoor unit installed indoors, and the indoor unit 7 is
It consisted of an indoor heat exchanger 8 for exchanging heat of refrigerant with indoor air.

[0003]

At present, in the global movement of protecting the global environment, the refrigerant of conventional air conditioners, such as R22, destroys the ozone layer. Although it is being converted to alternative refrigerant R410A, etc., from the viewpoint of prevention of global warming, R410A is almost the same as R22, and furthermore, a refrigerant that simultaneously solves the two aspects of prevention of ozone layer destruction and prevention of global warming It has been demanded. As one of such refrigerants, HC (hydrocarbon) such as propane gas, which is a combustible gas, is being studied. If a leak occurs, all the flammable refrigerant in the air conditioner leaks into the room, and there is a problem that there is a very high risk of explosion and the like. In the present invention, in view of the above problems, in the case of an air conditioner using a flammable refrigerant, even if a refrigerant leaks from the indoor unit, the leakage of the refrigerant is partially stopped, and the air with little danger It aims at providing a harmony machine.

[0004]

According to the present invention, in order to solve the above-mentioned problems, an outdoor unit having a compressor, an outdoor heat exchanger, and an expansion mechanism and an indoor unit having an indoor heat exchanger are sequentially piped. In an air conditioner that is connected by a flammable refrigerant, an open / close valve is provided on the discharge side of the compressor in the outdoor unit, and the expansion mechanism is an electronic expansion valve, and the flammable refrigerant is supplied indoors. A gas detector for detecting leakage is provided, and the gas detector is configured to control opening and closing of the on-off valve and the electronic expansion valve.

[0005] An outdoor unit having a compressor, a four-way valve, an outdoor heat exchanger, and an expansion mechanism and an indoor unit having an indoor heat exchanger are sequentially connected by piping and filled with a flammable refrigerant. In a heat pump type air conditioner, an on-off valve is provided between the four-way valve in the outdoor unit and the indoor heat exchanger, and the expansion mechanism is an electronic expansion valve to detect leakage of the flammable refrigerant into the room. Gas detectors
The on-off valve and the electronic expansion valve are controlled to be opened and closed by the gas detector.

Further, the gas detector is provided inside the indoor unit.

When the gas detector detects the leakage of the flammable refrigerant during the cooling operation, the electronic expansion valve is closed first, and after a predetermined time, the on-off valve is closed, and the compressor is closed. The configuration is such that it is controlled to stop.

Further, when the gas detector detects the leakage of the flammable refrigerant during the heating operation, the on-off valve is closed first, and after a predetermined time, the electronic expansion valve is closed, and the compressor is closed. The configuration is such that it is controlled to stop.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the embodiments of the present invention shown in FIGS. First, a first embodiment of the present invention shown in FIGS. 1 and 2 and FIGS. 4 and 5 will be described. As shown in the refrigerant circuit diagrams of FIGS. 1 and 2, reference numeral 1 denotes an outdoor unit installed outdoors. The outdoor unit 1 includes a compressor 2 for compressing refrigerant vapor,
A four-way valve 3 for switching the flow of the discharged refrigerant in accordance with the cooling operation and the heating operation, an outdoor heat exchanger 4 for exchanging the heat of the refrigerant with the outside air, and an electronic device as an expansion mechanism through which the refrigerant passes and adiabatically expands. It comprises an expansion valve 5 and an on-off valve 6 provided between the four-way valve 3 and an indoor heat exchanger 8 to be described later. Reference numeral 7 denotes an indoor unit installed indoors. The indoor unit 7 includes an indoor heat exchanger 8 for exchanging heat of refrigerant with indoor air. Is provided with a gas detector (not shown) for detecting the pressure.
The heat pump type refrigerant circuit having the above configuration is filled with HC (hydrocarbon) flammable refrigerant such as propane gas.

Next, the operation of the above configuration will be described. FIG. 4 shows a schematic block diagram of the control device, and FIG. 5 shows the operation timing of each element. First, a case where a refrigerant leak occurs during the cooling operation shown in FIG. 1 will be described. When a leak of the flammable refrigerant is detected by the gas detector installed inside the indoor unit 7, a detection signal of the gas detector 9 is transmitted to the indoor unit control unit 10, as shown in FIG. The indoor unit control unit 10 transmits a signal for commanding a gas leak operation during the cooling operation to the outdoor unit control unit 11 based on the signal and the fact that the cooling operation is being performed, and the outdoor unit control unit 11 The electronic expansion valve 5, the on-off valve 6, and the compressor 2 are operated at the operation timings shown. As shown in FIG. 5A, first, the electronic expansion valve 5 is closed.
Until the on-off valve 6 is closed after a predetermined time, the compressor 2 continues to operate. Therefore, the flammable refrigerant in the indoor unit 7 is continuously sucked into the outdoor unit 1 through the on-off valve 6, The residual refrigerant in the indoor unit 7 is reduced as much as possible. After a predetermined time, the on-off valve 6 is closed, and immediately thereafter, the compressor 2 is stopped, so that most of the flammable refrigerant is stored inside the outdoor unit 1 and leakage of the flammable refrigerant into the room Can be suppressed very slightly.

Next, a case where refrigerant leakage occurs during the heating operation shown in FIG. 2 will be described. When a leak of the flammable refrigerant is detected by the gas detector installed inside the indoor unit 7, a detection signal of the gas detector 9 is transmitted to the indoor unit control unit 10, as shown in FIG. The indoor unit controller 10 transmits a signal for commanding a gas leak operation during the heating operation to the outdoor unit controller 11 based on the signal and the fact that the heating operation is being performed. The electronic expansion valve 5, the on-off valve 6, and the compressor 2 are operated at the operation timings shown. As shown in FIG. 5B, the compressor 2 is continuously operated until the on-off valve 6 is closed and the electronic expansion valve 5 is closed after a predetermined time. The flammable refrigerant in the indoor unit 7 is continuously sucked into the outdoor unit 1 through 5, and the residual refrigerant in the indoor unit 7 is reduced as much as possible. After a predetermined time, the electronic expansion valve 5 is closed, and immediately after that, the compressor 2 is stopped, so that most of the flammable refrigerant is stored inside the outdoor unit 1 and the flammable refrigerant Leakage can be very slightly suppressed. Further, by providing the gas detector inside the indoor unit 7, the leakage of the flammable refrigerant can be detected at an early stage before spreading to the room, and the leakage of the flammable refrigerant to the room can be more effectively performed. Can be suppressed.

Next, a second embodiment of the present invention shown in FIGS. 3, 4 and 5 will be described. As shown in the refrigerant circuit diagram of FIG. 3, reference numeral 1 denotes an outdoor unit installed outdoors. The outdoor unit 1 includes a compressor 2 for compressing refrigerant vapor and an outdoor heat for exchanging heat of the refrigerant with the outside air. An exchanger 4, an electronic expansion valve 5, which is an expansion mechanism through which the refrigerant passes and adiabatically expands;
An on-off valve 6 is provided between the compressor 2 and an indoor heat exchanger 8 to be described later. Reference numeral 7 denotes an indoor unit installed indoors. The indoor unit 7 includes an indoor heat exchanger 8 for exchanging heat of refrigerant with indoor air. Is provided with a gas detector (not shown) for detecting the pressure. In the refrigerant circuit of the above configuration,
It is filled with HC (hydrocarbon) flammable refrigerant such as propane gas.

Next, the operation of the above configuration will be described. A case where a refrigerant leak occurs during the cooling operation shown in FIG. 3 will be described. When a leak of the flammable refrigerant is detected by the gas detector installed inside the indoor unit 7, a detection signal of the gas detector 9 is transmitted to the indoor unit control unit 10, as shown in FIG. The indoor unit control unit 10 transmits a signal for commanding a gas leak operation during the cooling operation to the outdoor unit control unit 11 based on the signal and the fact that the cooling operation is being performed, and the outdoor unit control unit 11 At the operation timings shown, the electronic expansion valve 5, the on-off valve 6, and the compressor 2
To work. As shown in FIG. 5A, the electronic expansion valve 5 is first closed, and the compressor 2 continues to operate until the open / close valve 6 closes after a predetermined time. , The flammable refrigerant in the indoor unit 7 is continuously drawn into the outdoor unit 1 to reduce the residual refrigerant in the indoor unit 7 as much as possible. After a predetermined time, the on-off valve 6 is closed, and immediately thereafter, the compressor 2 is stopped, so that most of the flammable refrigerant is stored inside the outdoor unit 1 and leakage of the flammable refrigerant into the room Can be suppressed very slightly. Further, by providing the gas detector inside the indoor unit 7, the leakage of the flammable refrigerant can be detected at an early stage before spreading to the room, and the leakage of the flammable refrigerant to the room can be more effectively performed. Can be suppressed.

[0014]

As described above, according to the present invention,
In an air conditioner using a flammable refrigerant, even if a refrigerant leaks from an indoor unit, the leakage of the refrigerant is partially stopped, and the air conditioner is less dangerous.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram showing a first embodiment of an air conditioner according to the present invention, showing a cooling operation state.

FIG. 2 is a refrigerant circuit diagram showing a first embodiment of the air conditioner according to the present invention, showing a heating operation state.

FIG. 3 is a refrigerant circuit diagram showing a second embodiment of the air conditioner according to the present invention, showing a cooling operation state.

FIG. 4 is a schematic block diagram of a control device for an air conditioner according to the present invention.

FIGS. 5A and 5B are operation timing charts of the air conditioner according to the present invention when detecting leakage of combustible refrigerant, where FIG. 5A shows a case where the air conditioner is detected in a cooling operation state, and FIG. is there.

FIG. 6 is a refrigerant circuit diagram of a conventional air conditioner.

[Explanation of symbols]

 Reference Signs List 1 outdoor unit 2 compressor 3 four-way valve 4 outdoor heat exchanger 5 electronic expansion valve (expansion mechanism) 6 on-off valve 7 indoor unit 8 indoor heat exchanger 9 gas detector

Claims (5)

[Claims] An air conditioner in which an outdoor unit having a compressor, an outdoor heat exchanger, and an expansion mechanism and an indoor unit having an indoor heat exchanger are sequentially connected by piping and filled with a flammable refrigerant. In the outdoor unit, an on-off valve is provided on the discharge side of the compressor in the outdoor unit, the expansion mechanism is an electronic expansion valve, and a gas detector for detecting leakage of the flammable refrigerant is provided in the room, and the gas detection An air conditioner characterized by controlling opening and closing of the on-off valve and the electronic expansion valve by a switch. 2. An outdoor unit having a compressor, a four-way valve, an outdoor heat exchanger and an expansion mechanism, and an indoor unit having an indoor heat exchanger are sequentially connected by piping and filled with a flammable refrigerant. In a heat pump type air conditioner, an on-off valve is provided between the four-way valve in the outdoor unit and the indoor heat exchanger, and the expansion mechanism is an electronic expansion valve, and leakage of the flammable refrigerant is detected indoors. An air conditioner comprising: a gas detector configured to open and close the on-off valve and the electronic expansion valve by the gas detector. 3. The air conditioner according to claim 1, wherein the gas detector is provided inside the indoor unit. 4. When the gas detector detects the leakage of the flammable refrigerant during the cooling operation, the electronic expansion valve is first closed, and after a predetermined time, the on-off valve is closed, and the compressor is closed. 4. The air conditioner according to claim 1, wherein the air conditioner is controlled to stop. 5. When the gas detector detects the leakage of the flammable refrigerant during the heating operation, the on-off valve is closed first, and after a predetermined time, the electronic expansion valve is closed, and the compressor is closed. The air conditioner according to claim 2, wherein the air conditioner is controlled to stop.