JP2021124215A - Air conditioner - Google Patents

Abstract

To provide an air conditioner enabling early detection of refrigerant leakage.SOLUTION: In an air conditioner, as a refrigerant, a combustible refrigerant is sealed in a refrigeration cycle constituting a path in which a refrigerant flows by annularly connecting an indoor side heat exchanger 6 of an indoor unit 2, an outdoor side heat exchanger 4 of an outdoor unit 1, a compressor 3 and a restriction device 5 via piping, and the indoor unit 2 and the outdoor unit 1 are connected via connection piping. In the air conditioner, output from a gas sensor 11 installed separately from the indoor unit 2 is received and leakage of the refrigerant from the refrigeration cycle to the outside is detected.SELECTED DRAWING: Figure 1

Description

The present invention relates to an air conditioner composed of a refrigeration cycle using a flammable refrigerant composed of propane (R290), isobutane (R600a), ethane (R170) and the like.

Refrigerants generally used in air conditioners have been converted to so-called CFC substitutes in response to the environmental problems of ozone layer depletion. However, CFC substitutes are greenhouse gases with a high GWP (Global Warming Potential) that promote the phenomenon of global warming. Therefore, in order to suppress global warming, it is required to switch to a refrigerant having a low GWP. In order to use a conventional flammable refrigerant such as a hydrocarbon as a refrigerant having a low GWP, it is necessary to prevent explosion and ignition to ensure safety. In Patent Document 1, as shown in FIG. 5, a gas sensor 10 is provided in the vicinity of the drain van in the lower part of the indoor unit 2, and when a flammable refrigerant having a specific gravity heavier than air leaks, it is detected by the gas sensor 10 through the drain van. Is equipped with a configuration that can prevent it from diffusing with a blower and becoming a flammable concentration.

Patent No. 3744330

The present disclosure provides an air conditioner for early detection of refrigerant leakage.

In the air conditioner in the present disclosure, the refrigerant flows by connecting the indoor heat exchanger of the indoor unit, the outdoor heat exchanger of the outdoor unit, the compressor, and the throttle device in a ring shape via a pipe. An air conditioner that encloses a flammable refrigerant as a refrigerant in the refrigeration cycle that constitutes the path and connects the indoor unit and the outdoor unit via a connecting pipe receives the output from the indoor unit and a separate gas sensor. It detects the leakage of refrigerant from the refrigeration cycle to the outside.

Since the air conditioner in the present disclosure diffuses the flammable refrigerant leaked to the outside of the indoor unit into the room, the leakage of the flammable refrigerant can be detected faster than the flammable refrigerant leaked to the indoor unit by the gas sensor separately installed from the indoor unit. Therefore, the safety against refrigerant leakage can be further improved.

Configuration diagram of the air conditioner according to the first embodiment of the present invention Layout of the separately installed gas sensor according to the first embodiment of the present invention Configuration diagram of the air conditioner according to the second embodiment of the present invention Configuration diagram of the air conditioner according to the third embodiment of the present invention Layout of gas sensor in the prior art

When the inventor came up with the present disclosure, since the heat exchanger is generally installed near the suction port above the indoor unit, when the refrigerant leaks from the heat exchanger corroded by the moisture of the suction air or the like. Since there is a high possibility that the refrigerant leaks to the outside of the indoor unit, it takes time for the refrigerant leaked upward to return to the indoor unit by free drop and be detected by the gas sensor installed in the lower part of the indoor unit of the prior art. Had the problem.
Therefore, the present disclosure constitutes a path through which the refrigerant flows by connecting the indoor heat exchanger of the indoor unit, the outdoor heat exchanger of the outdoor unit, the compressor, and the throttle device in an annular shape via a pipe. In the air conditioner that encloses a flammable refrigerant as a refrigerant in the refrigerating cycle and connects the indoor unit and the outdoor unit via a connecting pipe, the refrigerating cycle receives the output from the indoor unit and the gas sensor separately installed. It detects the leakage of refrigerant from the air to the outside.

Hereinafter, embodiments will be described in detail with reference to the drawings. However, more detailed explanation than necessary may be omitted. For example, detailed explanations of already well-known matters or duplicate explanations for substantially the same configuration may be omitted.

It should be noted that the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

(Embodiment 1)
Hereinafter, the first embodiment will be described with reference to FIGS. 1 and 2.

FIG. 1 shows the configuration of an air conditioner according to the first embodiment of the present invention. 1 is an outdoor unit, 2 is an indoor unit, 3 is a compressor, 4 is an outdoor heat exchanger, 5 is a throttle device, 6 is an indoor heat exchanger, and the outdoor unit has a compressor 3, an outdoor heat exchange. The vessel 4, the throttle device 5, and the indoor heat exchanger 6 of the indoor unit 2 are connected in a ring shape via a pipe to form a path through which the refrigerant flows, and a flammable refrigerant is sealed therein as a refrigerant. This is a refrigeration cycle in which the outdoor unit 1 and the indoor unit 2 are connected via a connecting pipe.
Reference numeral 7 denotes a four-way valve, which is connected to the discharge side of the compressor 3 to switch between cooling operation and heating operation. 8 is an outdoor fan, 9 is an indoor fan (first fan), 10 is an indoor unit gas sensor, and 11 is a separately installed gas sensor.

FIG. 2 shows the installation location of the separately installed gas sensor 11. The separately installed gas sensor 11 is arranged in contact with the wall and the floor in the vicinity directly below the indoor unit below the outlet of the indoor unit 2, and outputs refrigerant leakage information from the gas sensor 11 when the refrigerant is detected.

Since the indoor heat exchanger 6 is installed near the suction port above the indoor unit 1, when the refrigerant leaks from the heat exchanger corroded by the moisture of the suction air, it leaks to the outside of the indoor unit 1. Therefore, the refrigerant leaking upward freely falls while diffusing into the room. Therefore, the separate gas sensor 11 on the outside can detect the leakage of the refrigerant earlier than the gas sensor 10 in the indoor unit inside the machine.

When the gas sensor 11 separately installed in the indoor unit detects that the flammable refrigerant has leaked to the outside of the indoor unit 2, the indoor unit fan 9 is rotated immediately after the detection to diffuse the indoor air. By diffusing the refrigerant leaked into the room into the air and lowering the concentration, combustion is suppressed, and by suppressing the combustion of the flammable refrigerant, the safety against refrigerant leakage can be further improved.

The flammable refrigerant is a mixed refrigerant containing propane (R290), isobutane (R600a), ethane (R170) and the like.

The gas sensor in this case may be installed inside the indoor unit or outside the indoor unit. The feature of this embodiment is that the gas sensor is installed outside the indoor unit, and the gas sensor may or may not be provided inside the indoor unit.

Further, the gas sensor that can be used in the present invention is not particularly limited as long as it is a high-sensitivity hydrocarbon gas sensor such as a semiconductor method, a heat ray type semiconductor method, a new ceramic method, a heat conduction method, an infrared method, and a contact combustion method. In the detection method, a leak signal may be transmitted when the peak concentration exceeds a predetermined value, or a leak signal may be transmitted when the leak concentration exceeds a predetermined value as the leakage amount.
(Embodiment 2)
Hereinafter, the first embodiment will be described with reference to FIG.

FIG. 3 shows the configuration of the air conditioner according to the second embodiment of the present invention. In addition to the first embodiment, the refrigerant discharge unit 14 capable of discharging the refrigerant into the atmosphere in the path of the gas pipe on the outdoor unit 1 side of the two connecting pipes connecting the outdoor unit 1 and the indoor unit 2 and the refrigerant discharge unit 14 thereof. A diffusion fan 15 arranged adjacent to the on-off valve 13 and the refrigerant discharge unit 14 is provided.

When the refrigerant leakage from the refrigeration cycle to the outside is detected by the indoor unit gas sensor 10 or the indoor unit separate gas sensor 11, the on-off valve 13 of the refrigerant discharge unit 14 is opened after the leakage is detected, and the refrigerant in all sections in the refrigeration cycle is externally used. Discharge. By discharging the refrigerant in the refrigeration cycle to the outside, the amount of the refrigerant leaking from the indoor unit 2 can be suppressed, and the total amount of the flammable refrigerant leaking to the indoor side can be reduced. At the same time, the diffusion fan 15 is rotated to promote the diffusion of the refrigerant discharged to the outside by the rotation of the fan. As a result, the refrigerant concentration can be lowered from the flammable region and safely discharged to the outside, and the safety when the flammable refrigerant is discharged to the outside from the outdoor unit 2 can be improved.
(Embodiment 3)
Hereinafter, the first embodiment will be described with reference to FIG.

FIG. 4 shows the configuration of the air conditioner according to the third embodiment of the present invention. In addition to the first embodiment, of the two connecting pipes connecting the outdoor unit 1 and the indoor unit 2, the gas pipe shutoff valve 16 is on the outdoor unit 1 side of the gas pipe, and the liquid pipe is shut off on the outdoor unit 1 side of the liquid pipe. A valve 17 is provided.

When the indoor unit gas sensor 10 or the indoor unit separate gas sensor 11 detects a refrigerant leak from the refrigeration cycle to the outside, the gas pipe shutoff valve 16 and the liquid pipe shutoff valve 17 are closed after the leak is detected.

When a leak occurs in the indoor unit 1, the flammable refrigerant remaining in the outdoor unit 1 of the refrigeration cycle can be prevented from leaking indoors. Therefore, the total amount of flammable refrigerant leaking indoors is reduced, and the safety against refrigerant leakage is further improved.

The techniques disclosed herein are useful for heat pump equipment that uses flammable refrigerants. It can also be applied to air conditioners or refrigeration equipment.

1 Outdoor unit 2 Indoor unit 3 Compressor 4 Outdoor heat exchanger 5 Squeezing device 6 Indoor heat exchanger 7 Four-way valve 8 Outdoor fan 9 Indoor fan (first fan)
10 Indoor unit gas sensor 11 Indoor unit separate gas sensor 12 Indoor door 13 On-off valve 14 Refrigerant discharge part 15 Diffusion fan (second fan)
16 Gas pipe shutoff valve 17 Liquid pipe shutoff valve

Claims (14)

In the refrigeration cycle in which the indoor heat exchanger of the indoor unit, the outdoor heat exchanger of the outdoor unit, the compressor, and the throttle device are connected in a ring shape via a pipe to form a path through which the refrigerant flows. In an air conditioner in which a flammable refrigerant is sealed as a refrigerant and the indoor unit and the outdoor unit are connected via a connecting pipe, an output from the indoor unit and a gas sensor separately installed is received from the refrigeration cycle. An air conditioner characterized by detecting refrigerant leakage to the outside. The air conditioner according to claim 1, wherein the gas sensor is installed below the outlet of the indoor unit. The air conditioner according to any one of claims 1 to 2, wherein the gas sensor is installed in contact with a wall. The air conditioner according to any one of claims 1 to 3, wherein the gas sensor is installed in contact with the floor. The air conditioner according to any one of claims 1 to 4, wherein the gas sensor is installed in the vicinity immediately below the indoor unit. The air conditioner according to any one of claims 1 to 5, wherein the indoor unit is further provided with a gas sensor installed in the indoor unit. The indoor unit includes a first fan, and the gas sensor detects a refrigerant leak from the refrigeration cycle to the outside, and after the leak is detected, the first fan is rotated to diffuse the indoor air. The air conditioner according to any one of claims 1 to 6. A refrigerant discharge unit capable of discharging a refrigerant to the atmosphere is arranged in the path outside the outdoor side of the refrigeration cycle, and the gas sensor detects a refrigerant leak from the refrigeration cycle to the outside. The air conditioner according to any one of claims 1 to 7, wherein the air conditioner is opened to discharge the refrigerant in all the paths in the refrigeration cycle. A second fan arranged adjacent to the refrigerant discharge unit is provided, the gas sensor detects the refrigerant leakage from the refrigeration cycle to the outside, and after the leakage detection, the refrigerant discharge unit is opened to enter the refrigeration cycle. The air conditioner according to claim 8, wherein the external discharge of the refrigerant in the entire section is performed while rotating the second fan. A shutoff valve that cuts off the connection of the refrigerant path between the indoor unit and the outdoor unit is provided, the gas sensor detects a refrigerant leak from the refrigeration cycle to the outside, and the shutoff valve is closed after the leak is detected. The air conditioner according to any one of claims 1 to 6. The air conditioner according to any one of claims 1 to 10, wherein the gas sensor is built in a remote controller for the air conditioner. The air conditioner according to any one of claims 1 to 11, wherein the indoor unit is a wall-mounted air conditioner. The air according to any one of claims 1 to 12, wherein the flammable refrigerant is a substance containing a simple substance of propane, isobutane or ethane or a mixture of two or more of them as a main component. Harmony machine. The air conditioner according to any one of claims 1 to 13, wherein the refrigerating machine oil inside the compressor is a substance having low mutual solubility with a flammable refrigerant.

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